Development of performance and combustion system of Atkinson cycle internal combustion engine

The application of hybrid vehicle is a practical technical solution to the energy shortage and the environmental pollution. The internal combustion engine (ICE) plays a key role in the development of the hybrid vehicle. Based on the requirements of the hybrid vehicle and the characteristic of Atkinson cycle, a set of designing methods for the Atkinson cycle gasoline engine is presented through the analysis of the optimized matching for the compression ratio, valve timing and the combustion chamber. The designing method has been verified by the bench test and the results show that the fuel consumption can be improved by 12%–15% with the reduction of the low speed torque by 10%, and the low fuel consumption region in the fuel map extends significantly with the rated power almost keeping constant. It may be of great reference for the development of hybrid vehicle technology in China.