Performance Simulation of a 2-stroke Opposed Piston Gasoline Engine for Series Hybrid

Abstract

A 2-stroke gasoline engine may have an opportunity as a high efficiency engine in series hybrid with avoiding the low-load operation. Therefore, for the 2-stroke opposed piston engine that uses both SI operation and HCCI operation, we optimized the parameters that maximize the thermal efficiency using 1D-CFD and optimization software. Since the miller cycle is realized by using the EX crank delay and the dynamic effect of exhaust, knocking can be avoided even with a very high volume ratio (geometric compression ratio). Combined with the low cooling loss of the opposed piston engine, high thermal efficiency may be realized.