rexresearch.com
Nikolay SHKOLNIK
Mini-Engine
https://www.youtube.com/watch?time_continue=1&v=0e785YnDmq0
How It Works : LiquidPiston X Engine
http://www.popularmechanics.com/technology/a21324/engine-startup-liquidpiston-powers-a-go-kart-with-a-4-pound-engine/
Jun 14, 2016
How a 4-Pound Engine Can Replace a
40-Pound Engine
by Avery Thompson
Engine startup LiquidPiston has radically
shrunk a go-kart engine, but it's the military applications
that has everyone really excited.
Connecticut-based startup LiquidPiston announced today that they
have built a small, compact engine that is powerful enough to
drive a go-kart. Their X-mini engine weighs just 4 pounds and has
three moving parts, and yet can produce 3 horsepower, enough to
replace the default 40-pound piston engine that normally powers
the go-kart.
LiquidPiston says that their X-mini is still in a testing phase,
and they hope to get the weight down to 3 pounds and the power up
to 5 hp. (The 40-pound piston engine produces about 6.5 hp.) In
the meantime, their little engine already packs a punch, as you
can see in the video below.
LiquidPiston announced last year that they received a $1 million
DARPA grant to develop their X-mini engine, and it appears that
they've succeeded. The 4-pound, 3-hp engine is small enough to fit
in the palm of your hand, yet it can power everything from
vehicles to generators to drones. The X-mini uses LiquidPiston's
proprietary rotary engine design and thermodynamic cycle which
offer vast improvements over both a traditional Wankel rotary
engine and common piston engines.
LiquidPiston says the X-mini can run on Jet Propellant 8, the
military's fuel of choice, making it an ideal candidate for all
sorts of military applications. For instance, the X-mini is small
and light enough to power a UAV, it can be part of a generator
that can be carried in a backpack, or it can even be used to power
military robotics. According to Alec Shkolnik, LiquidPiston's
co-founder and president, "[DARPA] is kinda agnostic as to the
actual application … they have so many different applications that
need power."
Shkolnik said that the X-mini is still early in testing, and they
have only just built their first working prototype, but he's
hopeful that the engine could see a commercial release sometime in
the next few years. When that happens, the X-mini could find its
way into lawnmowers, emergency generators, and even small vehicles
like mopeds.
http://www.popularmechanics.com/cars/a8174/liquidpistons-hyper-efficient-engine-turning-the-rotary-inside-out-13817971/
Oct 17, 2012
LiquidPiston's Hyper-Efficient Engine:
Turning the Rotary Inside Out
A new spin on the internal combustion engine by startup
LiquidPiston aims for a leap in efficiency from 20 percent to
50 percent.
by
Ben Wojdyla
As automakers augment the reciprocating piston engine with hybrid
systems and improved accessories, independent inventors are busily
working to make huge improvements to the basic efficiency of the
internal combustion engine. Novel designs are popping up at
engineering expos everywhere, and the newest comes from
Bloomfield, Conn.-based LiquidPiston. Its X1 engine is a simple
machine with just three moving parts and thirteen major
components, but it aims to raise thermal efficiency from the 20
percent of a normal gas engine to more than 50 percent, with
drastic reductions in weight and size. How? By wasting much less
energy during the course of an combustion cycle.
Up to 80 percent of the energy in fossil fuels is thrown away
normal engines through the heat and pressure of exhaust, or dumped
to the atmosphere through the radiator. LiquidPiston's design
attempt to capture all of that waste within a tiny package. "We
stretched the performance curves in every direction to get much
higher efficiency," said Alec Shkolnik, President and CEO of
LiquidPiston, "We took the best parts of many different thermal
cycles and combined them." The design is theoretically capable of
75 percent thermal efficiency, but the group is targeting 57
percent in real world applications, still a huge jump.
The basic idea is similar to a Wankel rotary, but turned on its
head. Where the rotor holds the seals in a normal Wankel, the
housing does that job in the X1 engine. This allows significant
reduction in oil consumption over a regular rotary motor. Other
enhancements include direct injection, a high compression ratio at
18:1, and a dramatic change to the geometry of the combustion
chamber, which maintains a constant volume during ignition. This
change means the air-fuel mixture auto-ignites like a diesel, and
can be burned much longer than normal. The result is a more
complete combustion ending in low emissions and very high chamber
pressures. This high pressure is allowed to act on the rotor until
it reaches nearly atmospheric pressures, so almost all the
available energy is extracted before the exhaust is physically
pushed out. Again, this is different than a normal internal
combustion engine, which releases very energetic, high-pressure
exhaust gas.
Some other slick features: Since the engine is designed to convert
so much more heat energy into mechanical force, less heat has to
be removed from the block, so there's actually no water cooling
system. In cases where the engine is under load and needs to cool
down, it can skip an fuel injection event and just suck in cool
air, which is then heated by the block and gets exhausted. Another
option is to inject water into the combustion chamber. This has
three effects: cooling the engine, reducing NOx emissions, and
converting some of the water to steam, which increases power.
The compact design of LiquidPiston's lab engine currently tips the
scales at 80 lbs for the 40-hp model. It would weigh less than 50
lbs in production, the company claims, far less than a comparable
40-hp diesel that would tip the scale at around 400 lbs.
LiquidPiston's current aim is to continue developing the engine
with an eye on the sub-100 hp market — compressors, hybrid
range-extenders, military applications, boat engines — and license
the intellectual property to manufacturing customers. We love
seeing plucky inventors like these to completely rethinking the
gasoline engine.
http://liquidpiston.com/
LiquidPiston develops advanced rotary
engines based on the company’s patented thermodynamic cycle
and engine architecture.
LiquidPiston, Inc.
1292a Blue Hills Avenue
Bloomfield, CT 06002
Phone: (860) 838-2677 info@liquidpiston.com
http://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=1589586
Paper No. ICEF2005-1221, pp. 835-845; 11 pages
doi:10.1115/ICEF2005-1221
ASME 2006 Internal Combustion Engine Division Spring Technical
Conference (ICES2006); Aachen, Germany, May 7–10, 2006
High Efficiency Hybrid Cycle
Engine
Nikolay Shkolnik and Alexander C. Shkolnik
Abstract
A “High Efficiency Hybrid Cycle” (HEHC) thermodynamic cycle is
explored. This four-stroke cycle borrows elements from Otto,
Diesel, Atkinson, and Rankine cycles. Air is compressed into an
isolated combustion chamber, allowing for true isochoric
combustion, and extended duration for combustion to proceed until
completion. Combustion products expand into a chamber with greater
volume than intake. We provide details of a compact HEHC design
implementation using rotary pistons and isolated rotating
combustion chambers. Two Pistons simultaneously rotate and
reciprocate and are held in position by two roller bearings. One
Piston performs intake and compression, while the other performs
exhaust and expansion. We predict a reduction of energy losses,
moving part counts, weight and size over conventional engines.
http://papers.sae.org/2008-01-2448/
doi:10.4271/2008-01-2448
Paper #: 2008-01-2448
Rotary High Efficiency Hybrid
Cycle Engine
Abstract:
In this paper we discuss a rotary implementation of the High
Efficiency Hybrid Cycle (HEHC) engine. HEHC is a thermodynamic
cycle which borrows elements of Diesel, Otto and Atkinson cycles,
characterized by 1) compression of air only (e.g. Diesel), 2)
constant volume heat addition (e.g. Otto), and 3) expansion to
atmospheric pressure (e.g. Atkinson). The engine consists of a
compressor, an isolated combustion chamber, and an expander. Both
compressor and expander consist of a simple design with two main
parts: a rotor and an oscillating rocker. Compared to conventional
internal combustion engines, in which all processes happen within
the same space but at different times, in this engine, all
processes are occurring simultaneously but in different chambers,
allowing for independent optimization of each process. The result
is an engine which may offer up to 57% peak efficiency, and above
50% sustained efficiency across typical driving loads.
http://liquidpiston.com/technology/technical-papers/
http://papers.sae.org/2014-32-0104/
Development of a Small Rotary SI/CI
Combustion Engine
Alexander Shkolnik, Daniele Littera, Mark Nickerson, and
Nikolay Shkolnik et al., SAE Technical Paper 2014-32-0104,
2014, doi:10.4271/2014-32-0104.
This paper describes the development of small rotary internal
combustion engines developed to operate on the High Efficiency
Hybrid Cycle (HEHC). The cycle, which combines high compression
ratio (CR), constant-volume (isochoric) combustion, and
overexpansion, has a theoretical efficiency of 75% using
air-standard assumptions and first-law analysis. This innovative
rotary engine architecture shows a potential indicated efficiency
of 60% and brake efficiency of >50%. As this engine does not
have poppet valves and the gas is fully expanded before the
exhaust stroke starts, the engine has potential to be quiet.
Similar to the Wankel rotary engine, the ‘X’ engine has only two
primary moving parts – a shaft and rotor, resulting in compact
size and offering low-vibration operation. Unlike the Wankel,
however, the X engine is uniquely configured to adopt the HEHC
cycle and its associated efficiency and low-noise benefits. The
result is an engine which is compact, lightweight, low-vibration,
quiet, and fuel-efficient.
Two prototype engines are discussed. The first engine is the
larger X1 engine (70hp), which operates on the HEHC with
compression-ignition (CI) of diesel fuel. A second engine, the
XMv3, is a scaled down X engine (70cc / 3HP) which operates with
spark-ignition (SI) of gasoline fuel. Scaling down the engine
presented unique challenges, but many of the important features of
the X engine and HEHC cycle were captured. Preliminary
experimental results including firing analysis are presented for
both engines. Further tuning and optimization is currently
underway to fully exploit the advantages of HEHC with the X
architecture engines.
Methods, devices and systems for power generation through liquid
piston internal combustion engine. The liquid piston internal
combustion engine of the invention, utilizes a novel, synergetic
combination of internal combustion and steam piston engines within
the framework of one and the same system. The engine may comprise
or a plurality of cylinders, each having a liquid piston. The ICE
(Internal Combustion Engine) system comprises six modules viz PGM
(Power Generating Module), ERS (Energy Recovery System), PCM
(Power Conversion Module), HAS (Hydraulic Shock Absorbers Module),
DAC (Data Acquisition & Control Module) and AEM (Auxiliary
Equipment Module).
US9353623
Seal Assembly for a Heat Engine
A seal assembly includes first and second seal
elements configured to lie adjacent to one another with a
lower portion of each one disposed in a groove and an upper
portion of each one projecting above the groove. The groove
has a length disposed transverse to the direction of relative
motion of a housing and a moving member and is located in the
housing. The seal elements are further configured so that a
contact surface of the upper portion of each seal element
abuts the moving member and configured to allow independent
movement of each seal element relative to each other in a
direction transverse to the groove length. The seal elements
are shaped to define a lubrication channel therebetween that
is configured to allow the passage of a lubricant therein so
as to lubricate motion of the seal elements relative to each
other and relative to the moving member.
US8863724
Isochoric Heat Addition Engines and Methods
Engines and methods execute a high efficiency
hybrid cycle, which is implemented in a volume within an
engine. The cycle includes isochoric heat addition and
over-expansion of the volume within the engine, wherein the
volume is reduced in a compression portion of the cycle from a
first quantity to a second quantity, the volume is held
substantially constant at the second quantity during a heat
addition portion of the cycle, and the volume is increased in
an expansion portion of the cycle to a third quantity, the
third quantity being larger than the first quantity.
US2011247583
Internal Combustion
Engine and Components Therefor
A rotary internal combustion engine includes crank-driven gates to
synchronously form chambers for the intake, compression,
combustion, expansion and exhaust of a working medium during a
high-efficiency hybrid engine cycle. A variety of rotor geometries
and sealing apparatuses may work with a rotary engines in the
execution of various engine cycles including, but not limited to,
a high-efficiency hybrid engine cycle.
A rotary engine has a cycloid rotor and a sealing grid including a
face seal that rotates with the rotor, and including other seals
that do not rotate with the rotor. As the rotor rotates within a
housing, the rotor, housing and seal grid form at least one
working chamber between them, the chamber undergoing a change from
initial volume V1 to V2, which is less than V1, thus compressing a
working medium, and subsequently expanding to volume V3, which may
be larger than V1, such that the chamber volume is a smooth and
continuous function of rotor's rotational angle.
An internal combustion rotary engine includes an air passage
configured to allow cool air to flow through the rotor as the
rotor moves relative to the housing within the engine. Some
embodiments include a removable fuel cartridge.
An internal combustion engine includes in one aspect a source of a
pressurized working medium and an expander. The expander has a
housing and a piston, movably mounted within and with respect to
the housing, to perform one of rotation and reciprocation, each
complete rotation or reciprocation defining at least a part of a
cycle of the engine. The expander also includes a septum, mounted
within the housing and movable with respect to the housing and the
piston so as to define in conjunction therewith, over first and
second angular ranges of the cycle, a working chamber that is
isolated from an intake port and an exhaust port. Combustion
occurs at least over the first angular range of the cycle to
provide heat to the working medium and so as to increase its
pressure. The working chamber over a second angular range of the
cycle expands in volume while the piston receives, from the
working medium as a result of its increased pressure, a force
relative to the housing that causes motion of the piston relative
to the housing.
Engines and methods execute a high efficiency hybrid cycle, which
is implemented in a volume within an engine. The cycle includes
isochoric heat addition and over-expansion of the volume within
the engine, wherein the volume is reduced in a compression portion
of the cycle from a first quantity to a second quantity, the
volume is held substantially constant at the second quantity
during a heat addition portion of the cycle, and the volume is
increased in an expansion portion of the cycle to a third
quantity, the third quantity being larger than the first quantity.