Spark Ignition 50cc Engine with the power 11 kW@7500 RPM and EURO-5 emission
Spark ignition 50сс engine with extreme parameters of operation, capitalizing unique thermodynamic cycle (S-cycle) that guarantees high specific both power (not less than 11 kW@7500 RPM) and torque, and provides fuel economy and environment friendliness – emission control up to the level of EURO-5
The technical proposal to create highly efficient reciprocating IC engines with the displacement not much than 50cc of the engine displacement.
Newly developed theory of the S-cycle leads to creation of a whole series of engines with significantly higher efficiency than the ones currently available on the market. Specifically, the authors expect the new engines to yield a net efficiency of over 65%. Thus, an engine of 50cc displacement must have power not less than 11 kW@7,500RPM. There is nothing astonishing about the last statement, if it’s taken into account that the separation of a complete cycle into two stages – intensive and extensive – is the key advantage in our design. Useful work is available from the first stage; the second one prepares fresh air charge for the next cycle; and the result is that you can expect our design reduces operational volumes and engine weight comparison to a conventional engine of the same displacement. US patent #5,870,893 and the document in MS Word file TermoSE.doc describe main features and the theory of the new thermodynamic cycle.
The target engine design has the following features (also see S-engineVehicleDrive.doc):
• The proposed engine represents a combination of conventional ICE producing useful work (a mechanical energy generator) and a piston compressor bringing air compression up to the parameters of fuel burning at the expense of residual energy of working gases.
• Claimed in the US patent #5,870,893 thermodynamic cycle of operation and the engine arrangement provide simultaneously both the maximum possible useful work and the highest efficiency.
• The proposed engine operates by a four-stroke cycle, but it performs a working stroke at each revolution of the crankshaft as in a two-stroke mode. Unlike a two-stroke engine, the claimed engine does not require cylinders scavenging as exhaust gases are “swept” into the atmosphere with the help of the working piston, and the preliminary compressed fresh air goes into the combustion chamber.
• In the proposed engine, useful work is performed at the maximum possible indicator pressure of working gases. When the working gases pressure drops to 1.5-2MPa, a piston compressor starts operating, therefore releasing the engine from extensive part of expansion process. Engine sizes decrease by 2-5 times leads to drastic reduction of the friction losses. Mechanical efficiency attains as high as 95% and up.
• A power-to-weight ratio of the proposed engine approaches the one of a gas turbine, and its efficiency is much higher than of any other ICE. Engine efficiency increase is provided by (1) the maximum possible air compression ratio, (2) the prolonged expansion of working gases, (3) the reduction in number of the piston movement at which useful work is not performed.
• The mean torque only slightly correlated with engine RPM and is close to its maximum. This provides the possibility to reduce the number of steps in the gearbox or to exclude it at all.
We built the working mock-up CB-1 of this design. To simplify the mechanical part of the design the working and compression pistons were connected through the solid kinematic joint. Files CB-1 Sketches 01.jpg and CB-1 Sketches 02.jpg carry layout of the CB-1 design.
CB-1 Engine Specifications
Engine Type: Gasoline, Supercharged (by built-in piston compressor), Water Cooled
Number of Cylinders: 2
Compression Ratio: 8:1
Expansion Ratio: 30
Number of compression cylinders: 2
Compression bore/stroke: 110/60 mm.
Dry Weight: ~110 kg
Dimensions – L x W x H: 750 x 350 x 400mm
Supercharge type: one-stage built-in piston compressor, one per each working cylinder
Performance Rating (expected)
Maximum Power: 125 kW (170 HP) @ 7,500 rpm
Fuel Economy: 155g/kW•hr
Files CB-1 Pic 02.jpg, CB-1 Pic 03.jpg, and CB-1 Pic 04.jpg show the prototype in the testing bed. The following objectives were pursued as results of building working mock-up CB-1:
• To check the configuration for mechanical design consistency
• Make sure that the gas exchange system functions and matches the one theoretically defined and computed at the earlier development stage
• To create the system of principles to compute thermal distribution for engines of the similar design
Theory and practice expertise gained by the team of engineers is useful for designing an actual 50cc engine for motorcycles, ATVs, scooters, mini-bikes, and other small vehicles. Such an engine gets competing advantages, and especially on the motorcycle market, since in many countries operators of vehicles powered by small engines of 50cc displacement (or below) are not required to have a driver’s license. The point is that due to the volume separation and prolonged expansion the certified volume of engine remains the same – 50cc, while volumes of the expansion cavity and the compressor are about 150cc and 120cc correspondingly. Furthermore, the prolonged expansion increases the combustion time that in turn, as it was noticed during the prototype testing, improves the environment friendliness of this kind of engines.
We are looking for the Joint Venture opportunities to advance the project to create high performance motorcycle engine of 50cc displacement (vehicles Honda Monkey, Gorilla, Benly, Dax, Cub, Super Cub, XR50 with engines Z50 JE, AB27E; vehicles Kawasaki AV 50, Suzuki GS 50, DR Z, Birdie 50, Yamaha Mate 50, Town Mate 50 and its Chinese clones like 1P39FMB are engines-prototypes) with the following parameters:
• Engine Type – Spark Ignition with the prolonged expansion and imbedded piston compressor
• Stroke Operation – 2-stroke
• Displacement – 49.9cc
• Bore (diameter of the working cylinder) – 39mm
• Bore (diameter of the expansion cylinder) – 90mm
• Bore (diameter of the compressor cylinder) – 90mm
• Stroke – 41.4mm
• Compression Ratio – 10 (4.0 – in compression cylinder, 2.5 – in working cylinder)
• Maximum Power – 11.2 kW@7,500RPM
• Maximum Torque – 26.6Nm@5,000RPM
• Engine Idling Frequency – 1,800RPM
• Average Specific Fuel Consumption – 220g/kW•hour
• Emission control standard – Euro-5
Additional information and data clearing up the technology and approaches are available upon request.
Problem this idea/invention addresses:
Motorcycle, moped, scooterette, motorbike, scooter individuals, racing team owners, etc
Attached files: Patent:
US 5,870,893Asking price:
] Available for consultation?
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