Abstract:

A new scheme was proposed for matching between engine and transmission system with the power
performance and fuel economy of an automobile being as matching objective, and with the engine rated power
and other relevant parameters being as given parameters, according to the demand of the automobile power
performance and engine performance. Total engine energy requirements and various system energy requirements
were analyzed by using energy flow. Automobile dynamics analysis was done under working conditions based
on the U.S. Environmental Protection Agency (EPA) Test Procedure to calculate circle fuel consumption using
empirical formulas with the fuel consumption being as design economy requirements, and with the performance
curves describing engine performances. The results show that the maximum speed is 198.5 km/h, the maximum
power factor is 0.463, the maximum gradient is 0.46, the acceleration time is 9.8 s when accelerating from 0 to 60
km, and the fuel consumption is 9.74 L/(100 km). Therefore, the matching method is reasonable.

Key words: automotive engine, transmission system, matching, energy flow, power Performances, economy efficiency