28 February 2007
New Engine to Slash 50% Off Emissions
by Sam Fountain
A Cambridgeshire firm’s new engine technology, reportedly capable of reducing CO2 emissions by 50 per cent, could become a commercial reality following a £40k award to develop a prototype.
Dexpress delivery: Tony Dye, MD of Epicam, shows the revolutionary dexpressor technology to Peter Howarth of specialist consultancy Technology Business Development
Epicam has broken cover after winning a national competition, ‘Springboard,’ set up by Shell to reward the most innovative and commercially viable ways of reducing CO2 output.
Current engine technology only takes advantage of approximately 20 per cent of the energy potentially made available by burning fossil fuels, with 30 per cent of the valuable energy being wasted as heat.
Epicam believes its ‘dexpressor’, which harvests this wasted heat, could improve the efficiency of the engine, thus decreasing the amount of CO2 released into the atmosphere by up to 50 per cent.
The dexpressor works on a similar principal to a turbocharger, harnessing energy associated with the engine’s exhaust and translating it into mechanical energy.
But where a turbo uses an impeller inside the exhaust manifold to drive a pump, Epicam’s technology collects the waste heat emitted by the exhaust and uses it to drive a pump-like rotor.
As a combustion engine runs, it produces hot exhaust gases which leave the engine system via the exhaust pipe. Engineers regard the heat produced by the engine as ‘low-grade,’ i.e. not sufficiently intense to be productive.
The unique technology, currently a computer model pending the development of a working prototype, accumulates and utilises this ‘low-grade’ energy in a closed system, heating water via a heat exchange coil around the exhaust manifold of the engine.
The water in this system is super-heated to around 370°C, past the stage of steam, becoming ‘super-critical water’ and building up 1000 bar of pressure. The pressure is used to turn two rotors, via an innovative pressure retention system, a pair of “low friction rotating devices.”
One of these rotors feeds into the crankshaft of the engine, lending its power to turn the wheels of the car.
It is the method of keeping the high pressure created in the system and using it to turn the crank that is the secret behind Epicam’s invention. The help given to the engine in turning the crank could translate into being able to reduce the capacity of the engine by up to 50 per cent; so less capacity equals less fuel burnt which in turn would create lower carbon dioxide emissions.
The £40k award will now give Epicam the financial capability to translate its dexpressor idea from a computer model into a working example of the technology, which the firm expects to complete in four to six months.
“This award is a strong endorsement of Epicam’s innovative approach to CO2 reduction and will help the company to fund the development of a working prototype for demonstration to engine manufacturers later this year,” said Tony Dye, Epicam’s MD.
The automotive industry is the entry point for the technology, according to Peter Howarth, who is working with Epicam on its business strategy. “But the technology could also be employed on a powerplant, or any system similar to an automotive engine which generates heat, and runs a driveshaft,” said Howarth.
The company is extremely hopeful about the potential of the innovative design, but doesn’t yet have any offers from the automotive industry --- “not at this early stage,” Howarth said.
A ROTARY DEVICE AND A METHOD OF OPERATING A ROTARY DEVICE
DYE ANTHONY OSBORNE (GB)
Applicant: EPICAM LTD (GB); DYE ANTHONY OSBORNE (GB)
Classification: - international: F01C1/12; F01C1/16; F01C1/20; F01C11/00; F01C1/00; F01C11/00; (IPC1-7): F01C1/12; F01C1/20; F01C11/00; F01C21/12; F01C21/16€€€€; - European: F01C11/00B2; F01C1/12B; F01C1/16; F01C1/20
Cited documents: WO9106747 // US6176695 // EP0116356 // WO9527844 // DE4325454
Abstract --- The invention relates to a rotary device, comprising: a chamber for receiving a charge of an air/fuel mixture and for oxidising the fuel by detonation; and a rotary expander having a transient chamber of variable volume, the transient chamber being in fluid communication with the detonation chamber during at least part of a cycle of rotation of the rotary expander, the rotary expander being arranged to be driven by expansion of the air/fuel mixture caused by detonation thereof.
AN ENGINE AND AN APPARATUS FOR PROVIDING FORCED ASPIRATION TO AN ENGINE
Abstract --- The invention provides an apparatus (20) for providing forced aspiration to an internai combustion engine (2). The apparatus comprises a first displacement device (24) for being driven by exhaust gas from an internai combustion engine to which the apparatus is in use mounted and, a second displacement device (22) operable to compress combustion gas for provision to an engine to which the apparatus is in use mounted. The first and second displacement devices are coupled such that when in use the first displacement device (24) is driven and causes the second displacement device (22) to operate.
Abstract --- The present invention relates to a rotary device, comprising a first rotor rotatabe about a first axis and having at its periphery at least one recess bounded by a curved surface; a stator about which the first rotor is arranged for rotation; a second rotor counter-rotatable to said first rotor about a second axis, parallel to said first axis, and having at least one radial lobe bounded by a curved surface; the first and second rotors being coupled for inter-meshing rotation to produce a transient chamber of progressively increasing or decreasing volume defined between said curved recess and lobe surfaces of said first and second rotors; a housing in which the rotors are enclosed, said housing having end surfaces abutting end surfaces of said inter-meshing rotors; and a rotor port arranged to enable a flow of a gas into or out of said at least one recess in the recess rotor, the port having dimensions at least one of which is greater than the distance between the outermost extent of the stator and the minimum radius of the recess in the recess rotor.
FUEL INJECTION ASSEMBLY
Publication number: WO0233245
Abstract --- A fuel injection assembly comprising a main structure (101) for mounting on an internal combustion engine, the main structure having one or more orifices (115) for injecting fuel directly into the combustion chamber of the internal combustion engine, and the main structure also having mounted thereon charge electrodes (105, 118) positioned to provide an electric field which passes through the flow of fuel, for charging fuel particles to improve atomisation. The main structure also has mounted thereon a spark electrode (104) adapted to provide a fuel ignition spark for the internal combustion engine. The main structure of the assembly is adapted for removable mounting, having a threaded portion (102) adapted to co-operate with a threaded aperture in the internal combustion engine, normally adapted to receive a convention spark plug.
Internal combustion engine fuel supply and tuning
Abstract --- A method for adjusting the fuel:air ratio supplied to an internal combustion engine comprises measuring cylinder pressure during each of a sample of engine cycles and obtaining a measure of the extent of variation of the combustion process, e.g. the extent of intercycle variation in said pressure at a corresponding stage in each cycle, comparing the said measure to a corresponding standard and adjusting the fuel:air ratio to cause said measure to approach the standard. Carried out continuously the method may be used for the management of the fuel supply to an engine. Alternatively, the method may be used for tuning an engine.
Inlet valve assembly for internal combustion engines
Abstract --- The invention provides an improved inlet valve assembly for use in internal combustion engines. Gas distribution mechanism are provided to divide the gas passing between the valve and the valve seat into a plurality of circumferentially spaced jets each having a radial component of motion. Preferably, the jets are inclined to the radial direction.