Based on a single cylinder engine

the effects of injection parameter

multiple injection and the Atkinson cycle on the performance of gasoline compression injection(GCI) engine at high loads were studied. The results show that with the single injection strategy

the injection pressure

injection timing and injection mass have significant effects on GCI combustion. Increasing injection pressure can increase the indicated mean effective pressure(IMEP) of the engine and reduce cycle-to-cycle variation

but too high injection pressure causes the combustion to be extremely sensitive to the change of the injection timing

which makes it difficult to organize normal combustion. The increase of fuel injection can increase IMEP

but excessive fuel injection mass will lead to the increase of incomplete combustion and the decrease of thermal efficiency. With the split injection strategy

the main injection timing plays a decisive role in combustion. Advancing the main injection timing improves the engine performance and increases the pressure rise rate simultaneously. And as the main injection timing is delayed

the engine performance is deteriorated

and the cycle-to-cycle variation becomes great. Increasing pilot injection ratio is beneficial to the improvement of engine performance

but excessive pilot injection ratio leads to less combustion controllability. The Atkinson cycle can obviously improve the thermal efficiency of GCI engine. The main reason is that it reduces negative work during the compression stroke

while maintaining positive work during the expansion stroke.