Dr. Daryoush Allaei didn’t set out to revolutionize the wind
industry, but he may have stumbled on an idea that could become a
major game changer, not only in the wind market, but the entire
field of energy production.
In a non-descript office in an unremarkable building on the north
side of Chaska’s Jonathan Industrial Park, sits a pair of
rudi-mentary prototypes ready to show the world a different way of
thinking.
The models illustrate the idea behind Invelox – a wind generation
system designed to capture, accelerate and concentrate wind power.
Life-size counterparts will be rolled out in the next few months
for testing. And if Allaei can convince the world that his idea
works, he can envision a day when his wind generation systems are
atop every building and every home all around the world.
“Once people taste something that can coexist with nature and
harvest wind, there’s no stopping us,” he said.
SheerWind was recently awarded the Cleantech Open’s North Central
Region Sustainability Award for the Invelox.
Born in Iran, Allaei came to the United States at the age of 20 to
study mechanics and earn his doctorate in structural and system
dynamics at Purdue University. Since graduating, he has founded a
number of companies, including the Chaska-based QRDC – a research
and development company specializing in energy flow control and
energy efficiency.
It was mid-2008 when Allaei was working on a proposal for the U.S.
Department of Energy regarding wind turbine vibration that he
realized people were going about wind harvesting all wrong.
Allaei noted a number of problems with traditional wind turbines
and wind farms. “Birds don’t like it, humans don’t like it, we’re
going to a dead end,” he said.
He developed a tower shaped like a giant old phonograph horn lying
on its back that could collect wind closer to the ground than
traditional turbines, thereby reducing the cost of construction
materials as well as operation and maintenance costs. “Harvest
en-ergy closest to the source,” he reasoned.
In addition to reducing costs, Allaei believes his creation to be
more efficient and more versatile than the kinds of windmills
people have used for thousands of years.
“It is based on a concept of elegant simplicity,” states his
promotional brochures. “Instead of a pinwheel, you begin with a
scoop.”
The Invelox (a combination of “increased” and “velocity”) captures
wind moving as slow as 2 mph, funnels it down a tapered passageway
designed to increase its speed, and into a ground-level generator.
Allaei believes the Invelox can outperform a tradi-tional 300-foot
turbine 3-to-1 at half the size and with one-tenth the land
needed. In addition, multiple towers could be connected to form a
wind farm.
The result is wind power ranging between 2.8 and 4.1 cents per
kilowatt hour. “The cost will be below natural gas,” said Allaei.
“Our target is below hydro[electric].”
“This will really make a difference in people’s lives,” he said.
Allaei spent six months working on his initial idea for the
Invelox. “All my engineers said it wouldn’t work,” he recalled.
But as they spent two years refining the models, no one could
prove to him that the Invelox wouldn’t work.
“The designs are complete and authorization to cut steel has been
given,” he said.
The first Invelox units will be installed in February or March and
will be tested for three months. He already has a number of
prospective customers eager to try out the system. He’s not
surprised.
Allaei asserts that his design, while being more environmentally
friendly, can better blend into natural and residential settings
making it a more attractive option than traditional wind turbines.
He notes that the Invelox design has the flexibility to be scaled
up or down for use in several markets from utilities to
residential and commercial to military. He also envisions a mobile
unit that could be dispatched during natural disasters to provide
ready power.
The Invelox, while initially envisioned for steel, could be made
out of a variety of materials at varying price points.
“Eventually, I want it to be biodegradable material,” he added.
For now, Allaei remains in the business of convincing people that
his invention can and will work. “There’s going to be huge
re-sistance,” he said.
“We are not going to be issue-free,” he added. “But there are
solutions.”
Allaei’s already received two patents (with several more pending)
and successfully lured former Army Corps of Engineers and Xcel
Energy bigwigs to join both his management team and the company’s
board of directors.
If he’s right about the Invelox, Allaei is poised to jump to the
forefront of energy production.
“It will be game changing,” he said. “Absolutely.”
Wind Power Unlike Any Other On Horizon
by
Lauren Craig
SheerWind is a Chaska, Minnesota-based
start-up with a wind power generator concept that looks
nothing like any wind turbine you have ever seen. The
venture’s “Invelox” technology recently won the 2011 CleanTech
Open’s Sustainability Award for the North Central Region.
SheerWind’s Founder and CEO, Dr. Daryoush Allaei, has 25 years
of research and development experience, including leading
projects funded by the U.S. Department of Defense and
Department of Energy (DOE).
Interestingly, his technical expertise is not in wind power,
or even renewable energy, but in systems
dynamics–specifically, noise and vibration. He first developed
the idea for Invelox in late 2008, while working on a proposal
for a project to monitor wind turbine vibration, in response
to a DOE solicitation.
“DOE wanted a technology that could monitor the vibration of
the [wind turbine] blades, to help them manage wind energy
more cost-effectively,” Allaei said to us in a recent
interview. “When I was reviewing what they were asking for, I
just thought, ‘Wow! They are trying to solve the wrong
problem.’ They were asking me to go 60 to 100 feet up in the
air, when what I really needed to do was bring [the cost of
wind energy] down for them. I thought something had to change.
So I closed my door and I sat down and thought about what else
we could do that makes more sense. That’s how I came up with
this idea of harvesting wind on the ground.”
The result is what to looks to be a pretty novel approach to
generating wind power. Allaei’s “Invelox” technology (named
for increasing velocity) looks more like a giant phonograph
player than a wind turbine. Essentially, it works by capturing
wind, funneling it into a tunnel to increase velocity, and
channeling it into a ground-based turbine.
Allaei typically describes the system by comparing it to a
hydroelectric dam:
“If you look at a hydro dam, the basic principle is to collect
water and then, down below there are small openings where the
water is allowed to escape. By simple physics, when you do
that, the water speeds up. It is in that small opening in dams
where the generator is placed. The generator is small, but it
makes a very large amount of power because the water is moving
very fast through that small opening. Invelox is basically an
air dam that collects wind instead of water.”
Sheerwind’s simulations and computer models indicate that the
Invelox technology can produce three times more power than a
conventional wind turbine, while mounted on a tower at least
25 percent shorter, and using a ground-based turbine with
blades 25 percent as long. Because the system is
shorter, smaller, and has fewer moving parts than a
conventional system, SheerWind expects to achieve savings of
16 to 38 percent per megawatt-hour (MWh) produced.
At 3.5 cents per kilowatt-hour, the technology is believed
capable of producing wind power at prices comparable to new
gas-fired generation.
sheerwind
Unlike the conventional tower-based turbine design, (“you put
the blade up in the sky and you are at the mercy of nature”),
Allaei says that Invelox has the potential to overcome many of
the challenges facing large-scale wind farm development. For
one, the technology can generate power at wind speeds as low
as 2 mph. This can make wind power feasible in areas where it
is currently not.
The Invelox generators can also be sited close to urban
centers of demand, and used in tandem with natural gas power
plants. This configuration would enable utilities to manage
wind power like a baseload resource.
Invelox also does not produce the vibrations that contribute
to what is known in the scientific community as “Wind Turbine
Syndrome.” Citing a 2009 study of communities located near
wind farms in Wales, Allaei explains that wind turbines
generate vibrations at frequencies too low for human ears to
detect, but at which some organs in the human body resonate,
such as the heart.
“The lower the frequency, the longer the vibrations travel,
like whales that communicate with each other from miles away
in the ocean…. There is evidence that this can cause people
that live near wind farms to get tired, get sick or throw up,”
Allaei explains.
Of course, Allaei knew that there would be skeptics. Since
1992, he has founded six companies, including QRDC, a
consulting firm specializing in noise and vibration control.
With over 100 publications, 25 U.S. patents and 14
international patents, but little experience in the power
industry, Allaei found himself having to convince high-level
utility executives that his idea will work. “When I first
started, I did not even have a business plan.” he said. “My
first test was to see if people in the power industry could
punch a whole in the argument that I was making. These are not
shy people. If they don’t like your idea, they will tell you
to your face.”
But, Allaei is inspired and convincing; and his ideas are
making sense to people who know the energy business. Craig
Mataczynski, former CEO and president of both RES Americas and
NRG, met with Allaei specifically “to prove that the
technology would not work.” Now, Mataczynski sits on
SheerWind’s board.
SheerWind has developed several laboratory prototypes and
full-scale computer models, and expects to begin field testing
in the first quarter of 2012. “We have received strong
traction from customers during development; and if our claims
are validated in the field, they will buy,” Allaei said.
He also envisions that the technology could be scaled down for
quick deployment after a disaster. “It would have far more
impact in our community and society than just as a
money-making business,” he said. ”Really, this [technology]
can change the equation. It can change wind energy from an
alternative to a main source of generation.”
US2010133847
TURBINE-INTAKE TOWER FOR
WIND ENERGY CONVERSION SYSTEMS
Inventor: ALLAEI DARYOUSH [US]
Applicant: QUALITY RES DEV & CONSULTING INC [US]
EC: F03D1/04 // Y02E10/72
FIELD
[0001] The present disclosure relates generally to wind energy
conversion and, in particular, the present disclosure relates
to turbine-intake towers for wind energy conversion systems.
BACKGROUND
[0002] Due to the recent energy problems that have arisen,
considerable interest has been given to wind power to be
converted efficiently into electrical energy. Most of the
developments and advancements have been focused on the
improvement of the aerodynamics of propeller-type turbines,
e.g., known as wind turbines and initially referred to as
windmills. Typically, each turbine-generator system is mounted
on the top of tall tower, where the taller the tower, the
higher the prevailing wind speed. The electrical power
generated from a wind turbine is proportional to cubic order
of the wind speed. Furthermore, the longer each turbine blade,
the higher the power generation. However, long blades are
costly, can be subjected to defects and failure, take up a
large amount of space, and generate excessive noise and
vibration. The electrical power generated from a wind turbine
is directly proportional to the square of the propeller
length. However, taller towers and longer propellers increase
not only the cost of material and installation, but also the
cost of maintenance.
[0003] The current wind power generation systems typically
suffer from low efficiency, high capital cost, unpredictable
failures, excessively high noise and vibration, and/or high
maintenance. Due to higher wind speed, large wind farms have
recently been installed at sea. These sea-based systems suffer
from even much higher capital and maintenance costs.
Therefore, the growth of wind farms has been slow at best.
[0004] One of the national goals is that wind energy must
provide 20% of the nation's electricity by the year 2030. This
level of wind power will support 500,000 jobs while saving the
consumers $128 billion by lowering the price of natural gas.
In addition, it will cut greenhouse gas emission that is
equivalent to taking 140,000,000 cars off the road. While no
breakthrough in wind power technology is needed to achieve
this goal, power transmission lines, reliability, reduction of
operation and maintenance costs, and reduction of downtime and
failure of wind turbines is crucial.
[0005] The operational and maintenance costs of wind turbines
should be reduced to make conversion of wind energy to
electrical power economically more viable. The wind turbines
must also become more reliable with reduced downtime and
failures. For example, for offshore wind turbines, the costs
for operation and maintenance are estimated in the order of 30
to 35% of the costs of electricity. Roughly 25% to 35% is
related to preventive maintenance while 65% to 75% is due to
corrective maintenance.
[0006] Wind turbines are complex machines with several
sub-machines that convert the kinetic energy of moving air to
electrical power. Extraction of a significant amount of energy
requires high wind speeds and large turbine diameters. In
general, turbine speeds are slow (about 20 rpm) and the speed
must be increased to a useful generator speed. A typical wind
machine has a 3-blade turbine of more than 60 meters in
diameter. This turbine drives a generator through a
speed-increasing gearbox that generally has a planetary first
stage and one or two additional parallel shaft stages. The
generator runs at about 1500 rpm and produces about 1.5 MW.
Many wind turbines are variable speed machines; the speed
depends on the wind conditions and can vary over a wide range.
For these machines, high power output requires high levels of
torque and accompanying high gear-mesh forces. Because of the
low speed of the turbine, the various gearbox components are
usually supported by rolling element bearings. These bearings
are subject to significant radial loads and need to be
carefully monitored to detect any degradation.
[0007] At present, with the increasing installed power of the
wind turbines, the application of offshore wind turbines, and
major problems with turbine blades and gearboxes, the
necessity of condition monitoring can no longer be neglected.
Some components, although designed for the turbine lifetime,
may require repair or fail earlier than expected. This is
emphasized by the approach of warranty and insurance companies
that simply require application of monitoring provisions.
Otherwise, expensive preventive replacements or inspections
should be carried out periodically.
[0008] For the reasons stated above, and for other reasons
stated below which will become apparent to those skilled in
the art upon reading and understanding the present
specification, there is a need in the art for alternatives to
existing wind power generation systems.
SUMMARY
[0009] An embodiment of the present invention provides a
turbine-intake tower for delivering wind to a turbine. The
turbine-intake tower has a hollow support column, an intake
nozzle assembly rotatably coupled to the support column, and a
tower nozzle disposed within the support column. The intake
nozzle assembly is configured to receive and to accelerate
wind. The tower nozzle is configured to receive the wind from
the intake nozzle assembly and to further accelerate the wind
received from the intake nozzle assembly for delivery to the
turbine.
BRIEF DESCRIPTION OF THE
DRAWINGS
[0010] FIG. 1 is a cut-away
perspective view of an embodiment of a wind energy
conversion system, according to an embodiment of the present
invention.
[0011] FIG. 2 is an enlarged
view of a portion of FIG. 1, according to another embodiment
of the present invention.
[0012] FIG. 3 is a cut-away
perspective view of another embodiment of a wind energy
conversion system, according to another embodiment of the
present invention.
[0013] FIG. 4 is an enlarged
view of a portion of FIG. 3, according to another embodiment
of the present invention.
[0014] FIG. 5 is a
perspective view of another embodiment of a wind energy
conversion system, according to another embodiment of the
present invention.
[0015] FIG. 6 a perspective
view of an embodiment of a wind farm, according to another
embodiment of the present invention.
DETAILED DESCRIPTION
[0016] In the following detailed description of the present
embodiments, reference is made to the accompanying drawings
that form a part hereof, and in which are shown by way of
illustration specific embodiments that may be practiced. These
embodiments are described in sufficient detail to enable those
skilled in the art to practice disclosed subject matter, and
it is to be understood that other embodiments may be utilized
and that process, electrical or mechanical changes may be made
without departing from the scope of the claimed subject
matter. The following detailed description is, therefore, not
to be taken in a limiting sense, and the scope of the claimed
subject matter is defined only by the appended claims and
equivalents thereof.
[0017] FIG. 1 is a cut-away perspective view of a wind energy
conversion system 100. Wind energy conversion system 100
includes a turbine-intake tower 110, a turbine 120 fluidly
coupled to turbine-intake tower 110, and an electrical
generator 130, such as a 60 Hz AC generator, coupled (e.g.,
mechanically coupled) to turbine 120.
[0018] Turbine-intake tower 110 has an inlet 140 and an outlet
142. Air enters turbine-intake tower 110 through inlet 140
flows through turbine-intake tower 110 and exits
turbine-intake tower 110 through outlet 142. The air exiting
though outlet 142 passes over the blades of turbine 120, as
shown in FIG. 2, an enlarged view of outlet 142, turbine 120,
and generator 130, causing turbine 120 to rotate. Rotation of
turbine 120 rotates the generator 130 via a suitable
transmission (not shown) that couples turbine 120 to generator
130.
[0019] Inlet 140 may have a screen or other devices to prevent
the entry of birds or other airborne objects. Any conventional
bird catcher device may be used in this system.
[0020] Turbine-intake tower 110 includes an intake nozzle
assembly 143 that includes a converging intake nozzle 144 and
that may include an integral collector 146 that is contiguous
with converging intake nozzle 144. Intake nozzle assembly 143
is rotatably coupled to a support column 150 of turbine-intake
tower 110 by means of a bearing 152. Support column 150 is
substantially vertical and acts to support intake nozzle
assembly 143 at a vertical height H above ground level 154,
where the height H is measured from a central longitudinal
axis 156 of intake nozzle assembly 143. The height H may be
about the same height as the hub of a turbine of a
conventional wind turbine system, where the turbine is mounted
atop a tower. For example the height H may be about 100 to
about 200 feet.
[0021] Support column 150 has a base 151 that may directly
contact the ground at ground level 154. Alternatively, intake
tower 110 may be positioned on and may be in direct contact
with a platform floating on water, for example, for offshore
application, an in which case ground level 154 would
correspond to the surface of the platform. Turbine 120 and
generator 130 are located at or near ground level, e.g., at
about the same vertical level as base 151 and about the same
vertical level as outlet 142, as shown in FIGS. 1 and 2.
[0022] Intake nozzle assembly 143 may be substantially
horizontal. That is, central longitudinal axis 156 of intake
nozzle assembly 143 may be substantially horizontal. Central
longitudinal axis 156 may be substantially parallel to the
direction of the wind and thus the direction of the air
entering intake nozzle assembly 143. The inner surfaces of
nozzle assembly 143 are made of a smooth material in order to
reduce losses due to surface friction.
[0023] Collector 146 extends in the direction of central
longitudinal axis 156 from an inlet plane 160 of
turbine-intake tower 110 to the dashed line 162, which marks
the exit of collector 146. The flow passage within collector
146 is substantially uniform in size between inlet plane 160
and the exit 162 of collector 146, i.e., the cross-sectional
area (perpendicular to the flow direction) of the flow passage
within collector 146 is substantially uniform between inlet
plane 160 and the exit 162. When inlet 140 is facing the wind
and central longitudinal axis 156 is substantially parallel to
the wind direction, collector 146 collects the wind.
[0024] Intake nozzle 144 is fluidly coupled to collector 146.
The flow passage within intake nozzle 144 converges (e.g.,
tapers) in the direction of central longitudinal axis 156,
starting at the exit 162 of collector 146 and ending at an
entrance to an elbow 164. That is, the cross-sectional area
(perpendicular to the flow direction) of the flow passage
within intake nozzle 144 decreases between exit 162 of
collector 146 and elbow 164, as shown in FIG. 1. Intake nozzle
144 acts to increase the flow velocity between exit 162 of
collector 146 and elbow 162. That is, passing the flow through
intake nozzle 144 causes the flow to converge and thus
accelerate. Note that intake nozzle 144 receives the wind from
collector 146 and accelerates the wind.
[0025] Elbow 164 is interposed between intake nozzle assembly
143 and bearing 152. As such, bearing 152 rotatably connects
an upper end of support column 150 to elbow 164.
[0026] Support column 150 is hollow. A converging tower nozzle
170 (e.g., a column nozzle) is located within an interior of
support column 150 and may extend from bearing 152 to an elbow
172 that is coupled to an outlet duct 174 (e.g., sometimes
referred to as the turbine inlet duct) that leads to outlet
142. As such, tower nozzle 170 is fluidly coupled to intake
nozzle 144 and outlet duct 174.
[0027] Tower nozzle 170 may be substantially vertical. For
example, a central longitudinal axis 176 of tower nozzle 170
is substantially vertical and is substantially perpendicular
to central longitudinal axis 156 of intake nozzle assembly
143, as shown in FIG. 1.
[0028] The flow passage within tower nozzle 170 converges
(e.g., tapers) in the direction of central longitudinal axis
176, e.g., in the downward vertical direction, starting at the
exit of elbow 164 and ending at an entrance to elbow 172. That
is, the cross-sectional area (perpendicular to the flow
direction) of the flow passage within tower nozzle 170
decreases between elbow 164 and elbow 172, as shown in FIG. 1.
Tower nozzle 170 acts to increase the flow velocity between
elbow 164 and elbow 172. That is, passing the flow through
tower nozzle 170 causes the flow to converge and thus
accelerate.
[0029] Outlet duct 174 is substantially horizontal. For
example, a central longitudinal axis 178 of outlet duct 174 is
substantially horizontal and is substantially perpendicular to
central longitudinal axis 176 of tower nozzle 170 and
substantially parallel to central longitudinal axis 156 of
intake nozzle assembly 143, as shown in FIG. 1. Elbow 172 and
outlet duct 174 direct the flow from tower nozzle 170 onto the
blades of turbine 120. The flow velocity at outlet 142, i.e.,
the outlet of turbine-intake tower 110 and of duct 174, is the
turbine inlet velocity.
[0030] Turbine 120 has a shaft 180 that is substantially
horizontal, i.e., shaft 180 has a central longitudinal axis
182 that is substantially horizontal and that is substantially
parallel to central longitudinal axis 178 of outlet duct 174.
For example, turbine 120 may be referred to as a
horizontal-axis turbine. Central longitudinal axis 178 of
outlet duct 174 central longitudinal axis 182 of shaft 180 may
be substantially collinear. Note that for this embodiment,
turbine-intake tower 110 has a substantially horizontal
outlet.
[0031] Alternatively, for another embodiment, elbow 172 and
outlet duct 174 may be removed, and a turbine 120 may be
located at the exit of tower nozzle 170 so that its shaft 180
is substantially vertical. For example, central longitudinal
axis 182 of shaft 180 is substantially vertical and is
substantially parallel and substantially collinear to central
longitudinal axis 176 of tower nozzle 170. In this embodiment,
turbine 120 may be referred to as a vertical-axis turbine.
Note that the flow velocity at the exit of tower nozzle 170 is
the turbine inlet velocity for this embodiment and that
turbine 120 receives the fluid flow directly from tower nozzle
170. As such, the exit of tower nozzle 170 is the outlet of
turbine-intake tower 110, meaning that turbine-intake tower
110 has a substantially vertical outlet.
[0032] Elbow 164 has a radius of curvature that acts to keep
flow losses relatively low. This means that the flow velocity
at the exit of intake nozzle 144 and the entrance to tower
nozzle 170 is substantially the same. Elbow 172 also has a
radius of curvature that acts to keep flow losses relatively
low. In addition, the losses in outlet duct 174 are relatively
small. Therefore, the flow velocity at the exit of tower
nozzle 170 and the exit of outlet duct 174 are substantially
the same. As such, intake nozzle 144 and tower nozzle 170 work
together to increase the flow velocity from the velocity at
inlet 140 (the wind velocity) to the velocity at outlet 142
(the turbine inlet velocity). Note that the inner surfaces of
the elbows, tower nozzle 170, and outlet duct 174 are made of
a smooth material in order to reduce losses due to surface
friction. Turbulence suppressors may be implemented to reduce
turbulence in elbows 164 and 172, intake nozzle assembly 143,
tower nozzle 170, and outlet duct 174 that may result from
imperfections and anomalies in elbows 164 and 172, intake
nozzle assembly 143, tower nozzle 170, and outlet duct 174.
[0033] Note that the flow (wind) velocity at inlet 140 is
substantially the same as the flow (wind) velocity at the
inlet of a wind turbine of a conventional wind turbine system.
This means that the flow velocity at the inlet to turbine 120
is higher than the flow velocity (the wind velocity) at the
inlet of the wind turbine of the conventional system, owing to
increasing the flow velocity using intake nozzle 144 and tower
nozzle 170. The increased velocity at the inlet to turbine 120
allows for shorter turbine blades compared to conventional
wind turbines.
[0034] For example, the power output of a turbine is
proportional to the cubic order of the turbine inlet velocity
and is proportional to the square of the blade length. Since
the turbine inlet velocity, as result of turbine-intake tower
110, of the system of the present invention is higher than the
wind velocity at the inlet of a turbine of a conventional wind
turbine system, the turbine system of the present invention
has a higher power output than the conventional wind turbine
system for the same blade length. This means that since the
power output of a turbine is proportional to the cubic order
of the turbine inlet velocity and is proportional to the
square of the blade length, the turbine of present invention
can have shorter blades than the blades of the turbines of
conventional wind turbine systems and still have a higher
power output. Shorter blades also result in less drag than
longer blades and thus result in less energy loss than longer
blades.
[0035] Shorter blades result in lower material costs,
installation costs, and maintenance costs compared to the
longer blades of the turbines of conventional wind turbine
systems. The shorter blades are less susceptible to defects
and failure, take up less space, and generate less noise and
vibration than the longer blades of the turbines of
conventional wind turbine systems.
[0036] Actuators 186, e.g., piezoelectric actuators, may be
physically coupled to the outer surface of intake nozzle
assembly 143, e.g., the outer surface of intake nozzle 144
and/or the outer surface of collector 146, as shown in FIGS. 1
and 5. For example, actuators 186 may be coupled in direct
physical contact with the outer surface of intake nozzle 144
and/or the outer surface of collector 146. Actuators 186 are
electrically coupled to a controller 190 for receiving
electrical signals from controller 190.
[0037] A wind speed sensor, such as an anemometer 192, may be
mounted on an outer surface of turbine-intake tower 110 at or
near the top of turbine-intake tower 110 for sensing the wind
speed. For example, anemometer 192 may be mounted on elbow
164, as shown in FIG. 1, or on intake nozzle assembly 143.
Anemometer 192 may be electrically coupled to controller 190
for sending electrical signals to controller 190 indicative of
the sensed wind speed. Note that although anemometer 192 is
positioned behind inlet 140, anemometer 192 is positioned at a
vertical level that is sufficiently above the upper surface of
intake nozzle assembly 143 so as to sense the prevailing wind
speed external to turbine-intake tower 110. As a result,
anemometer 192 effectively measures the prevailing wind speed
upstream of inlet 140.
[0038] A wind direction sensor, such as a wind vane 194, may
be mounted on an outer surface of turbine-intake tower 110 at
or near the top of turbine-intake tower 110 for sensing the
wind direction. Wind vane 194 catches the wind and rotates
intake nozzle assembly 143 relative to support column 150 such
that inlet 140 is directed into the wind, e.g., so that
central longitudinal axis 156 of intake nozzle assembly 143 is
parallel to the wind direction. Wind vane 194 may be
electrically coupled to controller 190 for sending electrical
signals to controller 190 indicative of the sensed wind
direction.
[0039] For another embodiment, upon receiving electrical
signals from wind vane 194, controller 190 may send electrical
signals to a yaw motor (not shown) located adjacent bearing
152. A yaw drive (not shown) may mechanically couple the yaw
motor to intake nozzle assembly 143. The signals instruct the
yaw motor to activate the yaw drive that in turn rotates
intake nozzle assembly 143 such that inlet 140 is directed
into the wind.
[0040] In response to receiving signals indicative of the wind
speed from anemometer 192, controller may send electrical
signals to actuators 186. Actuators 186 may then adjust the
shape (e.g., contour) of intake nozzle assembly 143 by
exerting forces on the outer surface of intake nozzle assembly
143 based on the wind speed. That is, the shape of collector
146 and/or the shape of intake nozzle 144 may be adjusted
based on the wind speed. For example, actuators may adjust the
diameter of collector 146 and/or a diameter of intake nozzle
144.
[0041] Controller 190 may store voltage values corresponding
to the voltages that need to be applied to an actuator 186 to
set a diameter at a certain numerical value. The certain
numerical value may correspond to a diameter that provides a
certain increase in velocity and/or reduced losses for a
certain wind velocity for a certain power output.
[0042] For example, anemometer 192 might detect a wind speed
and send a signal indicative of the wind speed to controller
190. Controller 190 may then determine the required velocity
at outlet 142 to produce a certain power. Controller 190 may
further determine how much voltage needs to be applied to
actuator 186 to adjust the diameter of intake nozzle 144
and/or collector 146 in order to produce the required velocity
at outlet 142 for the detected wind speed. Similarly,
controller 190 may adjust the diameter of collector 146 and/or
a diameter of intake nozzle 144 to reduce flow losses based on
a detected wind speed.
[0043] In the event that anemometer 192 detects a wind speed
that is excessive, e.g., above a certain value, and that could
cause damage to turbine 120 and/or generator 130, controller
190 might send a signal to solenoid activated bleed-off valves
193 located at the elbows 164 and 172 that causes the
bleed-off valves 193 to open. Opening the bleed-off valves 193
causes a portion of the flow to be bled off, reducing the
turbine inlet velocity to an acceptable value. For example, a
portion of the flow may be bled off between intake nozzle
assembly 143 and tower nozzle 170, and a portion of the flow
may be bled off between tower nozzle 170 and turbine 120. For
one embodiment, the bled-off flows may be directed to another
turbine.
[0044] After intake nozzle assembly 143 is rotated such that
inlet 140 is directed into the wind and central longitudinal
axis 156 is substantially parallel to the wind direction,
collector 146 collects the wind and directs the wind to intake
nozzle 144. Intake nozzle 144 accelerates the wind. Elbow 164
receives the accelerated wind from intake nozzle 143 and
directs the wind to tower nozzle 170 by turning the wind by
substantially 90 degrees. Tower nozzle 170 further accelerates
the wind. For one embodiment, elbow 172 receives the further
accelerated wind from tower nozzle 170 and directs the wind to
outlet duct 174 turbine 120 by turning the wind by
substantially 90 degrees. Outlet duct 174 directs the wind to
turbine 120, e.g., when turbine 120 is a horizontal-axis
turbine. For another embodiment, e.g., when turbine 120 is a
vertical-axis turbine, turbine 120 may receive the wind
directly from tower nozzle 170 while the wind is flowing
substantially vertically downward.
[0045] FIG. 3 is a cut-away perspective view of a wind energy
conversion system 300. Common numbering is used in FIGS. 1 and
3 to identify components common to FIGS. 1 and 3. The common
components are as discussed above in conjunction with FIG. 1.
[0046] Wind energy conversion system 300 includes
turbine-intake tower 110, turbine 120, and electrical
generator 130. An outlet 342 of turbine-intake tower 110 is
located at the exit of tower nozzle 170 and is coupled to
subterranean plumbing, such as a subterranean flow delivery
system 355. Subterranean flow delivery system 355 is fluidly
coupled to tower nozzle 170. Subterranean flow delivery system
355 receives the accelerated flow exiting tower nozzle 170,
e.g., while the wind is flowing substantially vertically
downward, and delivers that flow to turbine 120, which is
fluidly coupled to subterranean flow delivery system 355.
[0047] FIG. 4 is an enlarged view showing the outlet 357 of
subterranean flow delivery system 355, turbine 120, and
generator 130. Common numbering is used in FIGS. 2 and 4 to
identify components common to FIGS. 2 and 4. The common
components are as discussed above in conjunction with FIGS. 1
and 2.
[0048] The flow velocity at outlet 357 is the turbine inlet
velocity. Turbine 120 is oriented so that its shaft 180 that
is substantially vertical, i.e., central longitudinal axis 182
of shaft 180 is substantially vertical. For example, turbine
120 may be referred to as a vertical-axis turbine.
[0049] Subterranean flow delivery system 355 includes a
substantially vertical duct 359 and a substantially vertical
duct 361. Ducts 359 and 361 are fluidly coupled by elbows 363
and a substantially horizontal duct 365. Turbulence
suppressors may be implemented to reduce turbulence in ducts
359 and 361, elbows 363, and duct 365.
[0050] Subterranean flow delivery system 355 acts to increase
the velocity of (e.g., accelerate) the flow exiting tower
nozzle 170 by taking advantage of the cooler temperatures
typically present under ground. The cooler temperatures cause
the walls of the subterranean flow delivery system 355 to be
at a lower temperature than the temperature of the air (wind)
entering turbine-intake tower 110.
[0051] For example, the temperature of the wall of duct 359 is
lower than the temperature of the air entering turbine-intake
tower 110. As a result, the air cools and becomes more dense
(e.g., heavier) as it flows downward through duct 359. The
difference between the lower density air entering
turbine-intake tower 110 and the higher density air in duct
359 produces a pumping effect that accelerates the downward
flow through duct 359 (note that cooler air has a natural
tendency to flow downward). The pumping effect acts to
increase the flow velocity in duct 359 and thus in
subterranean flow delivery system 355, meaning that the
turbine inlet velocity is increased.
[0052] In an alternative embodiment, turbine-intake tower 110,
turbine 120, and generator 130 may be located on a platform
floating on water, and subterranean flow delivery system 355
may be located under the surface of the water. In this
embodiment, subterranean flow delivery system 355 will act to
increase the flow velocity in the same way as when
subterranean flow delivery system 355 was located under
ground, owing to the lower temperatures that typically occur
below the surface of water.
[0053] For another embodiment, the outputs of two or more
turbine-intake towers 110 may be sent to a single turbine 120
coupled to a single generator 130, as shown for a wind energy
conversion system 500 in FIG. 5. In particular, the outlet
ducts 174 are coupled to a single outlet 542 directed at
turbine 120. Note that the flow velocity at outlet 542 is the
turbine inlet velocity. Common numbering is used in FIGS. 1
and 5 to identify components common to FIGS. 1 and 5.
[0054] For another embodiment, two or more turbine-intake
towers 110 may be coupled to a subterranean flow delivery
system, such as subterranean flow delivery system 355 (FIG.
3). Alternatively, each of the two or more turbine-intake
towers 110 may be respectively coupled to respective ones of
two or more subterranean flow delivery systems 355, and each
of the subterranean flow delivery systems 355 may be coupled
to single outlet 542 of FIG. 5.
[0055] FIG. 6 is a perspective view of a wind farm 600. For
one embodiment, wind farm 600 may include a plurality of wind
energy conversion systems 100, as described above in
conjunction with FIGS. 1 and 2. Alternatively, a wind farm may
include a plurality of wind energy conversion systems 300
having turbine-intake towers 110 coupled to subterranean
plumbing, as described above in conjunction with FIGS. 3 and
4. In another embodiment, a wind farm may include a plurality
of turbine-intake towers 110 coupled to a single outlet
directed at a single turbine, as shown in FIG. 5.
[0056] In the disclosed embodiments, the turbine and generator
are located at or near ground level and are easier to access
than the turbine and generator installed on the top of a tower
in conventional wind power systems. This acts to reduce
maintenance costs and noise and vibration. The noise and
vibration often results in damage to conventional wind power
systems and their supporting structures, thereby inducing
failure. In addition, reducing the length of the turbine
blades, as described above, reduces the initial capital cost,
installation cost, and the lifetime maintenance cost of the
turbine.
[0057] The disclosed embodiments allow for centralizing the
wind power generation farms and thus increase efficiency and
reduce cost. Centralization of the wind power generation will
also make the implementation in the national grid much easier.
[0058] The disclosed embodiments can be implemented as single
units for single households. A single unit may also be
installed on rooftop, large ships, and other moving (e.g.
automobiles) or still systems. The disclosed embodiments can
also be implemented in groups in any number that suits the
power requirements. The disclosed embodiments can be
implemented in commercial wind power generation farms
installed on land or offshore.
CONCLUSION
[0059] Although specific embodiments have been illustrated and
described herein it is manifestly intended that the scope of
the claimed subject matter be limited only by the following
claims and equivalents thereof.
WO2011028502
POWER GENERATING SKIN
STRUCTURE AND POWER GENERATION SYSTEM THEREFOR
Inventor: ALLAEI DARYOUSH
Applicant: QUALITY RES DEV & CONSULTING INC
EC:F03B17/06B // F03B17/06C
IPC: F03D1/00
Description
CROSS REFERENCE TO RELATED
APPLICATIONS
This application is related to U.S. Patent Application Serial
No. 12/466,840 (pending), filed May 15, 2009, titled "KINETIC
HYDROPOWER GENERATION SYSTEM AND INTAKE THEREFORE," which is a
continuation in part of U.S. Patent Application Serial No.
12/369,949 (pending), filed February 12, 2009, titled
"TURBINE-INTAKE TOWER FOR WIND ENERGY CONVERSION SYSTEMS,"
both of which applications are commonly assigned and both of
which applications are incorporated, in their entirety, herein
by reference.
FIELD
The present disclosure relates generally to power generation
and, in particular, the present disclosure relates to power
generating skin structures.
BACKGROUND
Conversion of the kinetic energy of a flowing fluid, such as
air (wind) or water, into electrical power is an attractive
method for producing electrical power. This typically involves
directing the flowing fluid through a turbine. The flowing
fluid causes the turbine to rotate an electrical generator,
causing the electrical generator to produce electrical power.
Examples of systems that convert the kinetic energy of flowing
fluids into electrical power include wind energy conversion
systems and kinetic hydropower generation systems. Kinetic
hydropower generation systems typically involve submerging a
turbine under water and directing flowing water current, e.g.,
due to waves, tides, etc., through the turbine.
Wind energy conversion systems typically include a wind
turbine and an electrical generator mounted atop a tower and
are typically large and noisy. Such systems are not well
suited for producing power, such as supplemental power, for
individual residences, especially in residential areas. Some
wind energy conversion systems involve placing a wind turbine
on a roof of residential or commercial buildings. However,
these turbines are susceptible to storm damage and may require
additional support structure to be added to the building to
support the weight of the turbine. The kinetic energy of fluid
flow relative to bodies moving through a fluid environment can
also be converted into electrical power. For example, the
kinetic energy of air relative to moving ground and aerial
(manned or unmanned) motor vehicles and of water relative to
moving marine and submarine (manned or unmanned) motor
vehicles can be used to generate electrical power for use by
the respective vehicle. However, mounting a turbine on the
exterior of a motor vehicle is impractical in that a turbine
produces noise, vibration, and added drag, and is not
esoterically appealing. Moreover, using ducting that has
relatively large openings at the front of a motor vehicle to
direct the fluid flow to one or more turbines within an
interior of a motor vehicle can result in additional drag on
the vehicle. For the reasons stated above, and for other
reasons stated below which will become apparent to those
skilled in the art upon reading and understanding the present
specification, there is a need in the art for alternatives to
existing systems for converting kinetic energy of flowing
fluids into electricity.
SUMMARY
An embodiment of the present invention provides a skin
structure. The skin structure has a skin and a power
generation system attached to the skin. The power generation
system has a turbine, one or more tubes fluidly coupled to the
turbine, and a generator configured to generate electrical
power in response to motion of the turbine.
BRIEF DESCRIPTION OF THE
DRAWINGS
Figure 1 is a perspective
view of an exterior of an embodiment of a skin structure,
according to an embodiment of the present invention.
Figure 2 is a perspective
view of an interior of the skin structure of Figure 1.
Figure 3 is a cross-sectional
view of a portion of an embodiment of a power system of a
skin structure, according to another embodiment of the
present invention.
Figure 4 is a cross-sectional
view of a portion of another embodiment of a power system of
a skin structure, according to another embodiment of the
present invention.
Figure 5 illustrates an
embodiment of a turbine/generator of a power system of a
skin structure, according to another embodiment of the
present invention.
Figure 6 illustrates another
embodiment of a turbine/generator of a power system of a
skin structure, according to another embodiment of the
present invention.
Figure 7 illustrates an
embodiment of a turbine of the turbine/generator of Figure 6.
Figure 8 is a perspective
view of an interior of another embodiment of a skin
structure, according to another embodiment of the present
invention.
Figure 9 is a cross-sectional
view of a portion of a power system of the skin structure of
Figure 8, according to another embodiment of the present
invention.
DETAILED DESCRIPTION
In the following detailed description of the present
embodiments, reference is made to the accompanying drawings
that form a part hereof, and in which are shown by way of
illustration specific embodiments that may be practiced. These
embodiments are described in sufficient detail to enable those
skilled in the art to practice disclosed subject matter, and
it is to be understood that other embodiments may be utilized
and that process, electrical or mechanical changes may be made
without departing from the scope of the claimed subject
matter. The following detailed description is, therefore, not
to be taken in a limiting sense, and the scope of the claimed
subject matter is defined only by the appended claims and
equivalents thereof.
Figure 1 is a perspective view of an exterior of a skin
structure 100, according to an embodiment. Figure 2 is a
perspective view of an interior of skin structure 100. Skin
structure 100 may include a skin 102. For one embodiment, skin
102, and thus skin structure 100, may form a portion of an
outer covering of a stationary structure, such as a roof
and/or sides of a building. As such, an interior surface 107
(Figure 2) of skin 102, and thus skin structure 100, may form
a portion of an interior surface of the stationary structure,
and an exterior surface 108 (Figure 1) of skin 102, and thus
skin structure 100, may form a portion of an exterior surface
of the stationary structure.
For another embodiment, skin 102, and thus skin structure 100,
may form a portion of an outer covering of a vehicle, such as
a ground or aerial (manned or unmanned) motor vehicle, e.g.,
an automobile, airplane, etc., or a marine or submarine
(manned or unmanned) motor vehicle, e.g. a boat, submarine,
etc. As such, interior surface 107 of skin 102, and thus skin
structure 100, may form a portion of an interior surface of
the vehicle, and exterior surface 108 of skin 102, and thus
skin structure 100, may form a portion of an exterior surface
of the vehicle. Skin structure 100 includes a power generation
system 104 attached to the skin and located on an interior
side of skin 102. Power generation system 104 converts kinetic
energy of a fluid-flow 110, e.g., a water-flow or airflow,
moving relative to and over exterior surface 108 of skin 102,
and thus of skin structure 100, as shown in Figure 1. For
example, the fluid flow may be substantially parallel to
exterior surface 108. Note that the portion of power
generation system 104 that is located on the interior side of
skin structure 100 is hidden from view in Figure 1 and is thus
shown using dashed lines in Figure 1.
Fluid-flow 110 may be wind moving past skin structure 100 when
skin structure 100 is stationary, such as when skin structure
100 forms an outer covering of a stationary structure.
Alternatively, fluid-flow 110 may be an airflow or water-flow
relative to a vehicle moving through air or water. As such,
fluid- flow 1 10 may be termed a forced fluid- flow.
Power generation system 104 has one or more tubes 120 on the
interior side of skin 102 that are communicatively (e.g.,
fluidly) coupled to a turbine of a turbine/generator 125
formed on the interior side of skin 102. For example, power
generation system 104 may include a manifold 130 that is
interposed between turbine/generator 125 and a plurality of
tubes 120 and that communicatively couples the plurality of
tubes 120 to the turbine of turbine/generator 125, as shown in
Figures 1 and 2. For one embodiment, pairs of tubes 120 may be
coupled to a manifold 140 interposed between manifold 130 and
tubes 120. Each manifold 140 communicatively couples its pair
of tubes 120 to manifold 130.
Each of tubes 120 has an inlet 135 that opens on the exterior
side of skin structure 100. For one embodiment, inlet 135 may
have circular cross-section having a diameter on the order of
one micron or one nanometer. As such, tubes 120 may be
referred to as micro- tubes or nano-tubes, and power
generation system 104 may be referred to as a micro-power-
generation-system or a nano-power-generation-system. Note that
the size of the micro-tubes or nano-tubes is exaggerated in
Figures 1 and 2 and may be several orders of magnitude less
that the thickness of skin 102 for some embodiments.
During operation, fluid- flow 110 enters tubes 120 though
inlets 135. The respective tubes 120 direct their respective
flows to the turbine turbine/generator 125. For example, pairs
of tubes 120 direct their respective flows to a respective
manifold 140. Each manifold 140 combines the flows from the
respective pair of tubes 120 and directs the combined flow to
manifold 130. Manifold 130 combines the flows from the
respective manifolds 140 and directs the combined flow to the
turbine of turbine/generator 125. As such, the turbine
receives the flow flowing through each of tubes 120.
The flow subsequently flows through the turbine, causing the
turbine to rotate. The generator of turbine/generator 125
generates electrical power in response to the rotation of the
turbine. That is, the generator converts the rotation of the
turbine into electrical power.
The flow exits the turbme, and thus power system 104, through
an outlet 150. That is, an outlet of the turbine is fluidly
coupled to outlet 150. Outlet 150 may be located on and may
open on the exterior side of skin structure 100, and the flow
152 exiting power system 104 through outlet 150 may be
returned to the flow 110, as shown in Figure 1.
Alternatively, outlet 150 may be located on and open on the
interior side of skin structure 100 so that the flow 152
exiting power system 104 through outlet 150 is directed away
from skin structure 100. For another embodiment, outlet 150
may be located in a portion of the stationary structure or
vehicle that is not exposed to fluid- flow 110.
For one embodiment, a stationary structure or vehicle may have
a plurality of power systems 104. For this embodiment, the
power from each power system 104 may be directed to a battery,
for example, for storage, such as for auxiliary power, to
reduce the power demand of an engine of a motor vehicle, or to
reduce the power that needs to be purchased to power a
stationary structure, such as a building.
Figure 3 is a cross-sectional view of a portion of power
system 104, according to another embodiment. As shown, the
flow passage within each tube 120 may be tapered and may
converge along the length of the tube from the inlet 135 to
turbine/generator 125. That is, the cross-sectional area
(perpendicular to the flow direction) of the flow passage
within each tube 120 decreases from the inlet 135 to the
turbine/generator 125.
Passing the flow through a tube 120 causes the flow to
converge and thus accelerate. That is, each tube 120 receives
fluid- flow 110 and accelerates fluid-flow 1 10. For
embodiments, where manifolds 130 and 140 are used, manifolds
130 and 140 may also have converging flow passages that act to
accelerate the flows received thereat. The accelerated flow is
delivered to the turbine. Note that the flow velocity within
tubes 120, manifold 130, and manifolds 140, may be further
increased, e.g., thermally assisted, by a temperature
difference that may occur between the exterior and interior
sides of skin structure 100, e.g., between the inlets 135 and
the inlet to the turbine. The increased flow velocity at the
inlet to the turbine allows for shorter turbine blades. For
example, the power output of some turbines is proportional to
the cubic order of the turbine inlet velocity and is typically
proportional to the square of the blade length. This means
that since the power output of a turbine is proportional to
the cubic order of the turbine inlet velocity and is
proportional to the square of the blade length, the turbine
can have shorter blades and still have a higher power output.
Shorter blades result in less drag than longer blades and thus
result in less energy loss than longer blades. Shorter blades
result in lower material costs, installation costs, and
maintenance costs compared to longer blades. The shorter
blades are less susceptible to defects and failure, take up
less space, and generate less noise and vibration than longer
blades.
As shown in Figures 1 and 3, the inlet 135 of each tube 120
may extend above exterior surface 108 of skin 102, e.g., at an
angle to exterior surface 108. The distance d by which the
inlet 135 of each tube 120 extends above exterior surface 108
may be on the order of one micron or one nanometer, so as to
not to significantly increase drag. Angling the inlet 135 of
each tube 120, as shown in Figures 1 and 3, enables the inlet
135 to capture a portion of fluid-flow 110 and to direct that
portion of fluid-flow 110 into the respective tube 120. The
outlet 150 of each tube may also extend above exterior surface
108 of skin 102, e.g., at an angle to exterior surface 108, by
a distance on the order of one micron or one nanometer, so as
to not to significantly increase drag.
Alternatively, inlet 135 and outlet 150 may be flush (e.g.,
substantially flush) with exterior surface 108, as shown in
the cross-sectional view of Figure 4. The fluid-flow 110 in
the configuration of Figure 4 may be parallel (e.g.,
substantially parallel) to exterior surface 108 or may be
perpendicular (e.g., substantially perpendicular) to exterior
surface 108, as shown in Figure 4. Note that the outlet 150 in
the configuration of Figure 4 may be located in a portion of
the stationary structure or vehicle that is not exposed to
fluid-flow 110, as indicated by the break in Figure 4.
Micro-actuators or nano-actuators 160 may be coupled in
physical contact with the outer surface of each tube 120, as
shown in Figure 3, and in physical contact with the outer
surface manifold 130 and of manifolds 140. Actuators 160 are
electrically coupled to a controller (not shown) for receiving
electrical signals therefrom. For example, a flow- velocity
sensor (not shown), e.g., of skin structure 100, the vehicle,
or the stationary structure, might detect a flow velocity of
fluid-flow 110 and send a signal indicative of the flow
velocity to the controller. For some embodiments, the flow-
velocity sensor may sense the velocity of fluid-flow 1 10
relative to exterior surface 108 of skin structure 100. For
example, the velocity of fluid-flow 110 may be the wind speed
or the velocity of the vehicle that includes skin structure
100. The flow- velocity sensor may be a micro- or nano-sensor.
The controller may apply a voltage to actuators 160, causing
the actuators to adjust a shape of the tubes 120, e.g., the
diameters of the tubes 120, and/or the shape of manifold 130,
e.g., the diameter of manifold 130, and/or the shapes of
manifolds 140, e.g., the diameters of manifolds 140, to
produce a certain flow velocity at the inlet to the turbine.
The controller may also cause the actuators to adjust the
diameters of the tubes 120 and/or manifold 130 and/or
manifolds 140 to reduce flow losses based on a detected flow
velocity of fluid-flow 110. This is similar to control and
operation of the actuators in U.S. Patent Application Serial
No. 12/466,840 and U.S. Patent Application Serial No.
12/369,949, which show and describe actuators, flow-velocity
sensors, and controllers.
Figure 5 illustrates a turbine/generator 525 that may be used
for turbine/generator 125 of power system 104 for one
embodiment. For example, turbine/generator 525 may include an
axial-flow turbine 510 having blades that rotate about a
rotational axis 515 that is parallel (e.g., substantially
parallel) to the fluid-flow 517, e.g., exiting manifold 130,
at the inlet to turbine 510. After the flow flows past turbine
510, it is directed out of power system 104 through outlet 150
(Figures 1 and 3).
An electrical generator 520, such as a 60 Hz AC generator, is
coupled (e.g., mechanically coupled) to turbine 120 via a
shaft and suitable transmission. For water applications,
electrical generator 520 is suitably waterproofed to protect
against electrical shorting and corrosion. Alternatively,
electrical generator 520 may be located out of the fluid-flow,
and the shaft and transmission may convey the rotation to the
location of electrical generator 520.
For one embodiment, the size of turbine/generator 525 may be
on the order of one micron or one nanometer, and may be
referred to as a micro- or nano- turbine/generator. For
example, turbine 510 may be a micro- or nano-turbine and have
a rotor diameter (e.g., blade tip-to-tip distance) on the
order of one micron or one nanometer, and generator 520 may be
a micro- or nano-generator and have a size on the order of one
micron or one nanometer.
During operation, fluid-flow 517 causes turbine 510 to rotate.
The rotation is transferred to generator 520, via the shaft
and transmission, thereby causing generator to rotate and
generate electrical power.
Figures 6 and 7 illustrate a turbine/generator 625 that may be
used for turbine/generator 125 of power system 104 for another
embodiment. For example, turbine/generator 625 may include a
radial-flow turbine 610 that rotates about a rotational axis
615 (Figure 7) that is parallel (e.g., substantially parallel)
to the fluid-flow 617 (Figures 6 and 7), e.g., exiting
manifold 130, at the inlet to turbine 610. After entering
turbine 610, fluid-flow 617 turns by about 90 degrees and
flows with radial-outward component over turbine blades 619
away from rotational axis 615 and toward a periphery 622 of
turbine 610, as shown in Figure 7. At the periphery 622, the
flow turns by about 90 degrees and flows parallel (e.g.,
substantially parallel) to axis 615.
The flow exits turbine 610, in a direction parallel (e.g.,
substantially parallel) to axis 615, through outlets 624 that
are formed in a stationary housing 626 that houses turbine 610
and that are located around the periphery 622, as shown in
Figures 6 and 7. The flow is then directed out of power system
104 through outlet 150 (Figures 1 and 3). Note that turbine
610 is located within housing 626 and is hidden from view in
Figure 7 and is thus shown using dashed lines in Figure 7.
For one embodiment, stationary housing 626 may include a
stationary electrical generator (not shown) that generates
electrical power from the motion of the tips of blades 619 of
turbine 610 or the motion of the periphery 622 of turbine 610
in a manner similar to the WT6000 Wind Turbine Gearless Blade
Tip Power System developed by HONEYWELL International, Inc.
(Morristown, NJ). For water applications, the electrical
generator is suitably waterproofed to protect against
electrical shorting and corrosion. Alternatively, turbine 610
may be coupled to an electrical generator by a shaft and
suitable transmission in a manner similar to that described
above in conjunction with electrical generator 520.
For one embodiment, the size of turbine/generator 625 may be
on the order of one micron or one nanometer, and may be
referred to as a micro- or nano- turbine/generator. For
example, turbine 610 may have a diameter on the order of one
micron or one nanometer and may be referred to as a micro- or
nano-turbine.
Figure 8 is a perspective view of an interior of a skin
structure 800, according to another embodiment. Common
reference numbers are used in Figure 8 and Figures 1-3 to
identify the same or substantially similar components. Skin
structure 800 may include the skin 102 described above in
conjunction with Figures 1-3. The power generation system 104,
described above in conjunction with Figures 1-3, is located on
the interior side of skin structure 800, with the inlets 135
of tubes 120 located on the interior side of skin structure
800.
The temperature of a fluid, such as water or air, on the
interior side of skin structure 800 is greater than the
temperature of the fluid on the exterior side of skin
structure 800. For example, skin structure 800 may form a
portion of an outer covering of a stationary structure, such
as a roof of a building, where the interior of the building is
at a higher temperature than the exterior. As such, interior
surface 107 (Figures 8 and 9) of skin 102, and thus skin
structure 800, may form a portion of an interior surface of
the stationary structure, and exterior surface 108 (Figure 9)
of skin 102, and thus skin structure 800, may form a portion
of an exterior surface of the stationary structure.
Skin structure 800 may form a portion a covering (e.g., a
hood) of an engine compartment of a motor vehicle, where the
interior of the engine compartment is at a higher temperature
than the exterior of the motor vehicle. For example, interior
surface 107 of skin 102, and thus skin structure 800, may form
a portion of an interior surface of the engine compartment,
and exterior surface 108 of skin 102, and thus skin structure
800, may form a portion of an exterior surface of the engine
compartment.
The temperature difference between the interior and exterior
produces a fluid-flow 810 on the interior side of skin
structure 800 that enters tubes 120 through their respective
inlets 135, as shown in Figure 9, a cross-sectional view of a
portion of power system 104. That is, the flow 810 is a
thermally driven flow. Note that inlets 135 open on the
interior side of skin structure 800 and thus open to an
interior of the stationary structure or the vehicle.
The fluid flows through each tube 120, into the respective
manifolds 140 (Figure 8), and into manifold 130, as described
above in conjunction with Figures 1 and 2. The flow
subsequently flows through the turbine of turbine generator
125, causing the turbine to rotate. The generator of
turbine/generator 125 generates electrical power in response
to the rotation of the turbine. The flow exits the turbine,
and thus power system 104, through outlet 150 on the exterior
side of skin 102, and thus of skin structure 800. That is, an
outlet of the turbine may be fluidly coupled to the exterior
side of skin 102.
Note that turbine/generator 125 may be the same (e.g.,
substantially the same) as turbine/generator 525, discussed
above in conjunction with Figure 5. Alternatively,
turbine/generator 125 may be the same (e.g., substantially the
same) as turbine/generator 625, discussed above in conjunction
with Figures 6-7.
Note that power system 104, and thus skin structure 800,
directs the relatively warm fluid from the interior side to
the exterior side while generating electrical power. This acts
to ventilate the interior of the stationary structure, such as
a warm attic under a roof during the summer, or the interior
of a motor vehicle, such as the engine compartment of the
motor vehicle. That is, skin structure 800 provides cooling
while producing electrical power.
For one embodiment, skin structure 100 and skin structure 800
may be used together on a stationary structure or a motor
vehicle.
US2010135766
KINETIC HYDROPOWER
GENERATION SYSTEM AND INTAKE THEREFORE
Inventor(s): ALLAEI
DARYOUSH
Applicant(s): QUALITY RES DEV &
CONSULTING
Classification: - international: F03B13/10; F03B13/12;
F03B13/26; F03B15/20; F03B17/06 - European: F03B11/02;
F03B17/06B; F03D1/04; Y02E10/28; Y02E10/72
Also published as: WO2010132534
Abstract -- A kinetic
hydropower generation system has a turbine and a generator
coupled to the turbine. An underwater intake nozzle assembly
is fluidly coupled to the turbine. For one embodiment, an
underwater tower nozzle may be fluidly coupled between the
turbine and the underwater intake nozzle assembly. The
underwater intake nozzle assembly may include a collector and
a converging nozzle.
CROSS REFERENCE TO RELATED
APPLICATION
This is a continuation in part of U.S. Patent Application
Serial No. 12/369,949 (pending), filed February 12, 2009,
titled "TURBINE-INTAKE TOWER FOR WIND ENERGY CONVERSION
SYSTEMS," which application is commonly assigned, the entire
contents of which are incorporated herein by reference.
FIELD
The present disclosure relates generally to kinetic hydropower
generation and, in particular, the present disclosure relates
to kinetic hydropower generation systems and intakes
therefore.
BACKGROUND
Due to the recent energy problems that have arisen,
considerable interest has been given to converting the kinetic
energy of fluid flows occurring in nature, e.g., wind flows in
wind energy conversion systems and water current flows in
kinetic hydropower generation systems, into electrical power.
For example, wind energy conversion systems involve directing
wind through a turbine. The wind causes the turbine to rotate
an electrical generator, causing the electrical generator to
produce electrical power.
Kinetic hydropower may be defined as, for example, dam-less
hydropower that is converted from energy found in the flowing
water currents of oceans, tides, rivers, lakes, and manmade
channels or conduits. For example, kinetic hydropower
generation systems typically involve submerging a turbine
under water and directing flowing water current through the
turbine, causing the turbine to rotate an electrical generator
for producing electrical power. However, water currents in
some bodies of water are too weak for kinetic hydropower
generation systems to be cost effective. For example, some
hydropower generation systems require current flow velocities
of at least about six feet per second in order to generate
enough energy for them to be cost-effective.
The electrical power generated from the turbines typically
used in wind energy conversion systems and kinetic hydropower
generation systems is proportional to cubic order of the flow
velocity, e.g., of the water or air, at the turbine inlet.
Furthermore, the longer each turbine blade, the higher the
power generation. However, long blades are costly, can be
subjected to defects and failure, take up a large amount of
space, and generate excessive noise and vibration. The
electrical power generated from these turbines is directly
proportional to the square of the propeller length. However,
longer propellers increase not only the cost of material and
installation, but also the cost of maintenance. As such,
current wind energy conversion systems and kinetic hydropower
generation systems typically suffer from low efficiency, high
capital cost, unpredictable failures, excessively high noise
and vibration, and/or high maintenance.
For the reasons stated above, and for other reasons stated
below which will become apparent to those skilled in the art
upon reading and understanding the present specification,
there is a need in the art for alternatives to existing wind
power generation systems and kinetic hydropower generation
systems.
SUMMARY
An embodiment of the present invention provides a kinetic
hydropower generation system. The kinetic hydropower
generation system has a turbine and a generator coupled to the
turbine. An underwater intake nozzle assembly is fluidly
coupled to the turbine. For one embodiment, an underwater
tower nozzle may be fluidly coupled between the turbine and
the underwater intake nozzle assembly. The underwater intake
nozzle assembly may include a collector and a converging
nozzle.
BRIEF DESCRIPTION OF THE
DRAWINGS
Figure 1 is a cut-away
perspective view of an embodiment of an energy conversion
system, according to an embodiment of the present invention.
Figure 2 is an enlarged view
of a portion of Figure 1 , according to another embodiment
of the present invention.
Figure 3 illustrates an
embodiment of a kinetic hydropower generation system
submerged in a body of water, according to another
embodiment of the present invention.
Figure 4 is a perspective
view of another embodiment of an energy conversion system,
according to another embodiment of the present invention.
Figure 5 illustrates another
embodiment of a kinetic hydropower generation system
submerged in a body of water, according to another
embodiment of the present invention.
Figure 6 is an enlarged view
of a portion of Figure 5, according to another embodiment of
the present invention.
Figure 7 a perspective view
of an embodiment of an array of energy conversion systems,
according to another embodiment of the present invention.
DETAILED
DESCRIPTION
In the following detailed description of the present
embodiments, reference is made to the accompanying drawings
that form a part hereof, and in which are shown by way of
illustration specific embodiments that may be practiced. These
embodiments are described in sufficient detail to enable those
skilled in the art to practice disclosed subject matter, and
it is to be understood that other embodiments may be utilized
and that process, electrical or mechanical changes may be made
without departing from the scope of the claimed subject
matter. The following detailed description is, therefore, not
to be taken in a limiting sense, and the scope of the claimed
subject matter is defined only by the appended claims and
equivalents thereof. Figure 1 is a cut-away perspective view
of an energy conversion system 100, such as a wind energy
conversion system or a kinetic hydropower generation system.
When operating as kinetic hydropower generation system, energy
conversion system 100 is submerged within a body of water,
such as a river, ocean, lake, or a manmade channel, etc., as
is shown in Figure 3 for a kinetic hydropower generation
system 300. Energy conversion system 100 includes a
turbine-intake tower 110, a turbine 120 fluidly coupled to
turbine- intake tower 110, and an electrical generator 130,
such as a 60 Hz AC generator, coupled (e.g., mechanically
coupled) to turbine 120.
For underwater applications, electrical generator 130 is
suitably waterproofed to protect against electrical shorting
and corrosion. To help guard against water corrosion
turbine-intake tower 110 and the blades of turbine 120 may be
fabricated from a suitable polymer or may be polymer-coated
metal. For other embodiments, turbine 120 and electrical
generator 130 may be located above water, such as on land or
on a platform floating on a body of water, and the water
exiting turbine-intake tower 110 may conveyed to turbine 120,
e.g., by conduits, such as pipes. Turbine-intake tower 110 has
an inlet 140 and an outlet 142. Air or water enters
turbine-intake tower 110 through inlet 140 flows through
turbine-intake tower 110 and exits turbine-intake tower 110
through outlet 142. The air or water exiting though outlet 142
passes over the blades of turbine 120, as shown in Figure 2,
an enlarged view of outlet 142, turbine 120, and generator
130, causing turbine 120 to rotate. Rotation of turbine 120
rotates the generator 130 via a suitable transmission (not
shown) that mechanically couples turbine 120 to generator 130.
Inlet 140 may have a screen or other devices to prevent the
entry of birds or other airborne objects for wind applications
or the entry offish or other water-born objects for underwater
applications. Any conventional bird-catcher or fish-catcher
device may be used in this system. Turbine-intake tower 110
includes an intake nozzle assembly 143 that includes a
converging intake nozzle 144 and that may include an integral
collector 146 that is contiguous with converging intake nozzle
144. For another embodiment, intake nozzle assembly 143 may be
rotatably coupled to a support column 150 of turbine- intake
tower 110 by means of a bearing 152. Support column 150 is
substantially vertical and acts to support intake nozzle
assembly 143 at a vertical height H above ground level 154,
where the height H is measured from a central longitudinal
axis 156 of intake nozzle assembly 143. Note that ground level
154 may correspond to the floor or the bottom 354 (Figure 3)
of the body of water in which turbine-intake tower 110 is
submerged.
For wind applications, the height H may be about the same
height as the hub of a turbine of a conventional wind turbine
system, where the turbine is mounted atop a tower. For
example, the height H may be about 100 to about 200 feet.
For some underwater applications, the height H may be
sufficient to position intake nozzle assembly 143 at a
distance above the bottom 354 of the body of water where the
flow velocity is at or near its highest. For example, for
rivers or shallow-water regions near shorelines, the current
flow velocity increases toward the surface of the water. For
example, in breakwater zones near shorelines, the flow
velocity near the surface is higher due to wave action and
tidal flow. As such, intake nozzle assembly 143 is positioned
to capture tidal flow and wave-induced current.
Support column 150 has a base 151 that may directly contact
the ground at ground level 154. Alternatively, for wind
applications, intake tower 110 may be positioned on and may be
in direct contact with a platform floating on water, for
example, for offshore application, in which case ground level
154 would correspond to the surface of the platform. Turbine
120 and generator 130 are located at or near ground level,
e.g., at about the same vertical level as base 151 and about
the same vertical level as outlet 142, as shown in Figures 1
and 2. For example, turbine 120 and generator 130 may be
located on the bottom 354 of the body of water, as shown in
Figure 3.
Intake nozzle assembly 143 may be substantially horizontal.
That is, central longitudinal axis 156 of intake nozzle
assembly 143 may be substantially horizontal. Central
longitudinal axis 156 may be substantially parallel to the
direction of the wind or water current and thus the direction
of the air or water entering intake nozzle assembly 143. The
inner surfaces of nozzle assembly 143 are made of a smooth
material in order to reduce losses due to surface friction.
Collector 146 extends in the direction of central longitudinal
axis 156 from an inlet plane 160 of turbine-intake tower 110
to the dashed line 162, which marks the exit of collector 146.
The flow passage within collector 146 is substantially uniform
in size between inlet plane 160 and the exit 162 of collector
146, i.e., the cross-sectional area (perpendicular to the flow
direction) of the flow passage within collector 146 is
substantially uniform between inlet plane 160 and the exit
162. When inlet 140 is facing the wind or the direction of the
water current and central longitudinal axis 156 is
substantially parallel to the wind or water flow direction,
collector 146 collects the wind or water flow. Intake nozzle
144 is fluidly coupled to collector 146. The flow passage
within intake nozzle 144 converges (e.g., tapers) in the
direction of central longitudinal axis 156, starting at the
exit 162 of collector 146 and ending at an entrance to an
elbow 164. That is, the cross-sectional area (perpendicular to
the flow direction) of the flow passage within intake nozzle
144 decreases between exit 162 of collector 146 and elbow 164,
as shown in Figure 1. Intake nozzle 144 acts to increase the
flow velocity between exit 162 of collector 146 and elbow 164.
That is, passing the flow through intake nozzle 144 causes the
flow to converge and thus accelerate. Note that intake nozzle
144 receives the wind or water current from collector 146 and
accelerates the wind or water current.
Elbow 164 is interposed between intake nozzle assembly 143 and
bearing 152. As such, bearing 152 rotatably connects an upper
end of support column 150 to elbow 164. Support column 150 is
hollow. A converging tower nozzle 170 (e.g., a column nozzle)
is located within an interior of support column 150 and may
extend from bearing 152 to an elbow 172 that is coupled to an
outlet duct 174 (e.g., sometimes referred to as the turbine
inlet duct) that leads to outlet 142. As such, tower nozzle
170 is fluidly coupled to intake nozzle 144 and outlet duct
174.
Tower nozzle 170 may be substantially vertical. For example, a
central longitudinal axis 176 of tower nozzle 170 is
substantially vertical and is substantially perpendicular to
central longitudinal axis 156 of intake nozzle assembly 143,
as shown in Figure 1. The flow passage within tower nozzle 170
converges (e.g., tapers) in the direction of central
longitudinal axis 176, e.g., in the downward vertical
direction, starting at the exit of elbow 164 and ending at an
entrance to elbow 172. That is, the cross-sectional area
(perpendicular to the flow direction) of the flow passage
within tower nozzle 170 decreases between elbow 164 and elbow
172, as shown in Figure 1. Tower nozzle 170 acts to increase
the flow velocity between elbow 164 and elbow 172. That is,
passing the flow through tower nozzle 170 causes the flow to
converge and thus accelerate.
Outlet duct 174 may be substantially horizontal. For example,
a central longitudinal axis 178 of outlet duct 174 may be
substantially horizontal and may be substantially
perpendicular to central longitudinal axis 176 of tower nozzle
170 and substantially parallel to central longitudinal axis
156 of intake nozzle assembly 143, as shown in Figure 1. Elbow
172 and outlet duct 174 direct the flow from tower nozzle 170
onto the blades of turbine 120. The flow velocity at outlet
142, i.e., the outlet of turbine-intake tower 110 and of duct
174, is the turbine inlet velocity.
Turbine 120 has a rotatable shaft 180 that is substantially
horizontal, i.e., shaft 180 has a central longitudinal axis
182 that is substantially horizontal and that is substantially
parallel to central longitudinal axis 178 of outlet duct 174.
Turbine blades 181 (Figure 2), e.g., three or more, are
mechanically coupled to shaft 180. Note that central
longitudinal axis 182 is the rotational axis of turbine 120
about which shaft 180 and the blades rotate.
Turbine 120 may be referred to as a horizontal-axis turbine.
Central longitudinal axis 178 of outlet duct 174 central
longitudinal axis 182 of shaft 180 maybe substantially
collinear. Note that for this embodiment, turbine-intake tower
110 has a substantially horizontal outlet. Also note that the
direction of the flow exiting outlet duct 174 is substantially
parallel to the central longitudinal axis 182 of shaft 180 and
thus the rotational axis of turbine 120.
Alternatively, for another embodiment, elbow 172 and outlet
duct 174 may be removed, and a turbine 120 may be located at
the exit of tower nozzle 170 so that its shaft 180 is
substantially vertical. For example, central longitudinal axis
182 of shaft 180 is substantially vertical and is
substantially parallel and substantially collinear to central
longitudinal axis 176 of tower nozzle 170. In this embodiment,
turbine 120 may be referred to as a vertical-axis turbine.
Note that the flow velocity at the exit of tower nozzle 170 is
the turbine inlet velocity for this embodiment and that
turbine 120 receives the fluid flow directly from tower nozzle
170. As such, the exit of tower nozzle 170 is the outlet of
turbine-intake tower 110, meaning that turbine-intake tower
110 has a substantially vertical outlet. Again, the direction
of the flow exiting tower nozzle 170 is substantially parallel
to the vertically oriented central longitudinal axis 182 of
shaft 180 and thus the rotational axis of turbine 120. Elbow
164 has a radius of curvature that acts to keep flow losses
relatively low.
This means that the flow velocity at the exit of intake nozzle
144 and the entrance to tower nozzle 170 is substantially the
same. Elbow 172 also has a radius of curvature that acts to
keep flow losses relatively low. In addition, the losses in
outlet duct 174 are relatively small. Therefore, the flow
velocity at the exit of tower nozzle 170 and the exit of
outlet duct 174 are substantially the same. As such, intake
nozzle 144 and tower nozzle 170 work together to increase the
flow velocity from the velocity at inlet 140 (the wind or
water current velocity) to the velocity at outlet 142 (the
turbine inlet velocity).
The inner surfaces of the elbows, tower nozzle 170, and outlet
duct 174 are made of a smooth material in order to reduce
losses due to surface friction. Turbulence suppressors may be
implemented to reduce turbulence in elbows 164 and 172, intake
nozzle assembly 143, tower nozzle 170, and outlet duct 174
that may result from imperfections and anomalies in elbows 164
and 172, intake nozzle assembly 143, tower nozzle 170, and
outlet duct 174.
Note that the flow (wind or water current) velocity at inlet
140 is substantially the same as the flow (wind or water
current) velocity at the inlet of a turbine of a conventional
wind energy conversion or a conventional kinetic hydropower
generation system. This means that the flow velocity at the
inlet to turbine 120 is higher than the flow velocity (wind or
water current) at the inlet of the turbines of conventional
wind energy conversion systems and conventional kinetic
hydropower generation systems, owing to increasing the flow
velocity using intake nozzle 144 and tower nozzle 170. The
increased velocity at the inlet to turbine 120 allows for
shorter turbine blades compared to the turbine blades for the
turbines of conventional wind energy conversion systems and
conventional kinetic hydropower generation systems.
For example, the power output of a turbine is typically
proportional to the cubic order of the turbine inlet velocity
and is typically proportional to the square of the blade
length. Since the turbine inlet velocity, as result of
turbine-intake tower 110, of the wind energy conversion
systems and the kinetic hydropower generation systems of the
present disclosure is higher than the wind or water current
velocity at the inlet of a turbine of a conventional wind
energy conversion system or a conventional kinetic hydropower
generation system, the wind energy conversion systems and the
kinetic hydropower generation systems of the present
disclosure have a higher power output than conventional wind
energy conversion systems and conventional kinetic hydropower
generation systems for the same blade length. This means that
since the power output of a turbine is proportional to the
cubic order of the turbine inlet velocity and is proportional
to the square of the blade length, the turbines of the wind
energy conversion systems and the kinetic hydropower
generation systems of the present disclosure can have shorter
blades than the blades of the turbines of conventional wind
energy conversion systems and conventional kinetic hydropower
generation systems and still have a higher power output.
Shorter blades result in less drag than longer blades and thus
result in less energy loss than longer blades. Shorter blades
result in lower material costs, installation costs, and
maintenance costs compared to the longer blades of the
turbines of conventional wind energy conversion systems and
conventional kinetic hydropower generation systems. The
shorter blades are less susceptible to defects and failure,
take up less space, and generate less noise and vibration than
the longer blades of the turbines of conventional wind energy
conversion systems and conventional kinetic hydropower
generation systems.
Actuators 186, e.g., piezoelectric actuators, may be
physically coupled to the outer surface of intake nozzle
assembly 143, e.g., the outer surface of intake nozzle 144
and/or the outer surface of collector 146, as shown in Figures
1, 3, and 4. For example, actuators 186 may be coupled in
direct physical contact with the outer surface of intake
nozzle 144 and/or the outer surface of collector 146.
Actuators 186 are electrically coupled to a controller 190 for
receiving electrical signals from controller 190.
A flow- velocity sensor 192, may be mounted on an outer
surface of turbine-intake tower 110 at or near the top of
turbine-intake tower 110 for sensing the velocity of the wind
or water current. For example, flow- velocity sensor 192 may
be mounted on elbow 164, as shown in Figure 1, or on intake
nozzle assembly 143. Flow-velocity sensor 192 may be
electrically coupled to controller 190 for sending electrical
signals to controller 190 indicative of the sensed wind or
water current flow velocity. Note that although flow- velocity
sensor 192 is positioned behind inlet 140, flow- velocity
sensor 192 is positioned at a vertical level that is
sufficiently above the upper surface of intake nozzle assembly
143 so as to sense the prevailing wind or water current flow
velocity external to turbine-intake tower 110. As a result,
flow- velocity sensor 192 effectively measures the prevailing
wind or water current flow velocity upstream of inlet 140.
A flow-direction sensor 194, may be mounted on an outer
surface of turbine- intake tower 110 at or near the top of
turbine-intake tower 110 for sensing the direction of the wind
or water current flow. Flow-direction sensor 194 catches the
wind or water flow such that the water current flow rotates
intake nozzle assembly 143 relative to support column 150 such
that inlet 140 is directed into the wind or water current
flow, e.g., so that central longitudinal axis 156 of intake
nozzle assembly 143 is substantially parallel to the wind or
water flow direction. Flow-direction sensor 194 may be
electrically coupled to controller 190 for sending electrical
signals to controller 190 indicative of the sensed wind or
water flow direction.
Kinetic hydropower generation systems that are configured to
convert the kinetic energy of tidal flows into electrical
power are exposed to bidirectional currents. That is, the
current flow is in one direction when the tide comes in and in
an opposite direction when the tide goes out. Flow-direction
sensor 194 catches the incoming or outgoing tide and rotates
intake nozzle assembly 143 so that inlet 140 is directed into
the incoming or outgoing tide. Note that rivers that flow into
the oceans act as tidal channels where the current direction
changes with the tide. For another embodiment, upon receiving
electrical signals from flow-direction sensor 194, controller
190 may send electrical signals to a yaw motor (not shown)
located adjacent bearing 152. A yaw drive (not shown) may
mechanically couple the yaw motor to intake nozzle assembly
143. The signals instruct the yaw motor to activate the yaw
drive that in turn rotates intake nozzle assembly 143 relative
to support column 150 and tower nozzle 170 such that inlet 140
is directed into the wind or the water current flow.
In response to receiving signals indicative of the wind or
water flow velocity from flow- velocity sensor 192, controller
190 may send electrical signals to actuators 186.
Actuators 186 may then adjust the shape (e.g., contour) of
intake nozzle assembly 143 by exerting forces on the outer
surface of intake nozzle assembly 143 based on the wind or
water flow velocity. That is, the shape of collector 146
and/or the shape of intake nozzle 144 may be adjusted based on
the wind or water flow velocity. For example, actuators 186
may adjust the diameter of collector 146 and/or a diameter of
intake nozzle 144.
Controller 190 may store voltage values corresponding to the
voltages that need to be applied to an actuator 186 to set a
diameter at a certain numerical value. The certain numerical
value may correspond to a diameter that provides a certain
increase in velocity and/or reduced losses for a certain wind
or water flow velocity for a certain power output. For
example, flow-velocity sensor 192 might detect a wind or water
flow velocity and send a signal indicative of the wind or
water flow velocity to controller 190. Controller 190 may then
determine the required velocity at outlet 142 to produce a
certain power. Controller 190 may further determine how much
voltage needs to be applied to an actuator 186 to adjust the
diameter of intake nozzle 144 and/or collector 146 in order to
produce the required velocity at outlet 142 for the detected
wind or water flow velocity. Similarly, controller 190 may
adjust the diameter of collector 146 and/or a diameter of
intake nozzle 144 to reduce flow losses based on a detected
wind or water flow velocity.
In the event that flow- velocity sensor 192 detects a wind or
water flow velocity that is excessive, e.g., above a certain
value, and that could cause damage to turbine 120 and/or
generator 130, controller 190 might send a signal to solenoid
activated bleed-off valves 193 located at the elbows 164 and
172 that causes the bleed-off valves 193 to open. Opening the
bleed-off valves 193 causes a portion of the flow to be bled
off, reducing the turbine inlet velocity to an acceptable
value. For example, a portion of the flow may be bled off
between intake nozzle assembly 143 and tower nozzle 170, and a
portion of the flow may be bled off between tower nozzle 170
and turbine 120. For one embodiment, the bled-off flows may be
directed to another turbine. After intake nozzle assembly 143
is rotated such that inlet 140 is directed into the wind or
water current flow and central longitudinal axis 156 is
substantially parallel to the wind or water current flow
direction, collector 146 collects the wind or water current
flow and directs the wind or water flow to intake nozzle 144.
Intake nozzle 144 accelerates the wind or water flow. Elbow
164 receives the accelerated wind or water flow from intake
nozzle 143 and directs the wind or water current flow to tower
nozzle 170 by turning the wind by substantially 90 degrees.
Tower nozzle 170 further accelerates the wind or water flow.
For one embodiment, elbow 172 receives the further accelerated
wind or water flow from tower nozzle 170 and directs the wind
or water flow to outlet duct 174 by turning the wind or water
flow by substantially 90 degrees. Outlet duct 174 directs the
wind or water flow to turbine 120, e.g., when turbine 120 is a
horizontal-axis turbine. For another embodiment, e.g., when
turbine 120 is a vertical-axis turbine, turbine 120 may
receive the wind or water flow directly from tower nozzle 170
while the wind or water is flowing substantially vertically
downward. For another embodiment, the outputs of two or more
turbine-intake towers 110 may be sent to a single turbine 120
coupled to a single generator 130, as shown for an energy
conversion system 400, such as a wind energy conversion system
or a kinetic hydropower generation system, in Figure 4. In
particular, the outlet ducts 174 are coupled to a single
outlet 442 directed at turbine 120. Note that the flow
velocity at outlet 442 is the turbine inlet velocity. Common
numbering is used in Figures 1 and 4 to identify components
common to Figures 1 and 4.
When energy conversion system 400 acts as a kinetic hydropower
generation system, energy conversion system 400 is submerged
under water. For another embodiment, only turbine-intake
towers 110 are submerged under water; and the single turbine
120 and generator 130 are located on land or on a floating
platform; and the water exiting the single outlet 442 is
conveyed to the turbine 120, e.g., by conduits, such as pipes.
Figure 5 illustrates a kinetic hydropower generation system
500 submerged in a body of water, such as a river, ocean,
lake, or a manmade channel, etc. Common numbering is used in
Figures 1-3 and 5 to identify components common to Figures 1-3
and 5. Kinetic hydropower generation system 500 includes the
nozzle assembly 143, as described above in conjunction with
Figure 1, positioned on bottom 354 of the body of water. Inlet
140 of nozzle assembly 143 is directed into the water current
flow. Intake nozzle assembly 143 may be substantially parallel
to bottom 354 of the body of water. That is, central
longitudinal axis 156 of intake nozzle assembly 143 maybe
substantially parallel to bottom 354 of the body of water.
Central longitudinal axis 156 may be substantially parallel to
the direction of the water current and thus the direction of
water entering intake nozzle assembly 143.
The central longitudinal axis 182 of turbine shaft 180 (Figure
2) is substantially parallel to and is substantially collinear
with longitudinal axis 156, as shown in Figure 6, an enlarged
view of outlet 542 of intake nozzle assembly 143, turbine 120,
and generator 130. As indicated above in conjunction with
Figures 1 and 2, central longitudinal axis 182 is the
rotational axis of turbine 120. Note that the direction of the
flow exiting intake nozzle assembly 143 is substantially
parallel to the central longitudinal axis 182 of shaft 180.
Nozzle assembly 143 operates as described above in conjunction
with Figure 1. That is, collector 146 collects the water
current flow and directs the water flow to intake nozzle 144.
Intake nozzle 144 accelerates the water flow and directs the
accelerated water flow onto blades of turbine 120, causing
turbine 120 to rotate generator 130 so that generator 130
generates electrical power.
Nozzle assembly 143 may include the flow- velocity sensor 192
(Figure 1) that is electrically coupled to controller 190 for
sending electrical signals to controller 190 indicative of the
sensed water current flow velocity. Controller 190 may cause
actuators 186 to adjust the diameter of collector 146 and/or a
diameter of intake nozzle 144 based on the detected water flow
velocity, as described above.
For example, controller 190 may determine how much voltage
needs to be applied to an actuator 186 to adjust the diameter
of intake nozzle 144 and/or collector 146 in order to produce
the required velocity at outlet 542 for the detected water
flow velocity. Controller 190 may further adjust the diameter
of collector 146 and/or a diameter of intake nozzle 144 to
reduce flow losses based on a detected water flow velocity.
For another embodiment, the outputs of two or more nozzle
assemblies 143 of a kinetic hydropower generation system may
be sent to a single turbine 120 coupled to a single generator
130 in a manner similar to that shown in Figure 4. For
example, the outlets 542 of the two or more nozzle assemblies
143 may be coupled to a single outlet, e.g., similar to outlet
442 in Figure 4, directed at turbine 120. Figure 7 is a
perspective view of an array 700 of energy conversion systems
100, as described above in conjunction with Figures 1 and 2.
Array 700 may be located above ground as a portion of a wind
farm or may be submerged in a body of water as a portion of an
underwater kinetic-hydropower- generation farm. The turbines
and generators of the respective energy conversion systems 100
of the underwater kinetic-hydropower- generation farm may be
located underwater or above water, e.g., on land or on a
floating platform.
A wind farm may include a plurality of above-ground
turbine-intake towers 110 coupled to a single outlet directed
at a single turbine, as shown in Figure 4. An underwater
kinetic-hydropower-generation farm may include a plurality of
underwater turbine-intake towers 110 coupled to a single
outlet directed at a single turbine. The single turbine of the
underwater kinetic-hydropower-generation farm may be located
on land or on a floating platform, and the water exiting the
single outlet may be conveyed to the on-land turbine, e.g., by
conduits, such as pipes.
For another embodiment, an underwater
kinetic-hydropower-generation farm may include an array of
underwater kinetic hydropower generation systems 500 (Figure
5). The turbines and generators of the respective energy
conversion systems 500 maybe located underwater or above
water, e.g., on land or on a floating platform. Alternatively,
an underwater kinetic-hydropower-generation farm may include
an array of nozzle assemblies 143, where nozzle assemblies of
the array are coupled to a single outlet directed at a single
turbine, where the single turbine and the generator coupled
thereto are underwater or are above water, e.g., on land or on
a floating platform.
Accelerating water current flow using the nozzle assembly 143
of Figure 5 or accelerating either wind or water current flow
using the turbine-intake towers 110 of Figures 1, 3, 4, and 7
acts to reduce the length of the turbine blades. Reducing the
length of the turbine blades acts to reduce the initial
capital cost, installation cost, and the lifetime maintenance
cost of the turbine. Accelerating the water current flow using
either nozzle assembly 143 or turbine-intake tower 110 acts to
increase water current flow velocities that might otherwise be
too low to be cost effective to levels that can be cost
effective.
Locating the turbine and generator above water as described in
some of the embodiments of the disclosed kinetic hydropower
generation systems enables easier to access the turbine and
generator than the underwater turbines and generators in
conventional kinetic hydropower generation systems. This acts
to reduce maintenance costs. Above-water turbines and
generators are not subjected to the type of water-induced
corrosion as is common in under-water turbines and generators.
Above-water generators are not subject to the type of
water-induced shorting that can occur with underwater
generators.
CONCLUSION
Although specific embodiments have been illustrated and
described herein it is manifestly intended that the scope of
the claimed subject matter be limited only by the following
claims and equivalents thereof.