Ultra-Downsizing of Internal Combustion Engines

The downsizing of internal combustion engines (ICE) is already recognized as a very suitable method for the concurrent enhancement of indicated fuel conversion efficiency (IFCE) and the lowering of CO₂ and NO_x emissions.

In this report, ultra-downsizing is introduced as an even higher stage of development of ICE. Ultra-downsizing will be implemented here by means of real Atkinson cycles using asymmetrical crank mechanisms, combined with multi-stage high-pressure turbocharging and very intensive intercooling. This will allow an increase of ICE performance while keeping the thermal and mechanical strain strength of engine components within the current usual limits.