Other cycles The very first internal combustion engines did not compress the mixture.The first part of the piston downstroke drew in a fuel-air mixture, then the inlet valve closed and, in the remainder of the down-stroke, the fuel-air mixture fired.
The diesel cycle is somewhat different. Split-cycle engines separate the four strokes of intake, compression, combustion and exhaust into two separate but paired cylinders.The first cylinder is used for intake and compression.
The compressed air is then transferred through a crossover passage from the compression cylinder into the second cylinder, where combustion and exhaust occur.A split-cycle engine is really an air compressor on one side with a combustion chamber on the other. Previous split-cycle engines have had two major problems?poor breathing (volumetric efficiency) and low thermal efficiency. However, new designs are being introduced that seek to address these problems. The Scuderi Engine addresses the breathing problem by reducing the clearance between the piston and the cylinder head through various turbo charging techniques. The Scuderi design requires the use of outwardly opening valves that enable the piston to move very close to the cylinder head without the interference of the valves. Scuderi addresses the low thermal efficiency via firing after top dead centre (ATDC). Firing ATDC can be accomplished by using high-pressure air in the transfer passage to create sonic flow and high turbulence in the power cylinder.Źródło: https://en.wikipedia.org/wiki/Internal_combustion_engine
Most cars in use today are propelled by an internal combustion engine, fueled by deflagration of gasoline or diesel.
Both fuels are known to cause air pollution and are also blamed for contributing to climate change and global warming.4 Rapidly increasing oil prices, concerns about oil dependence, tightening environmental laws and restrictions on greenhouse gas emissions are propelling work on alternative power systems for cars.