增压发动机被动预燃室的仿真分析

Simulation analysis of passive pre-combustion chamber of supercharged engine

用CONVERGE软件对预燃室燃烧系统模型进行网格划分,设置关键参数以研究预燃室喷孔数对湍流比、湍动能、空燃比、缸内混合气流速的影响。结果表明:进气行程结束前,预燃室喷孔数对湍流比无影响;气门关闭时,预燃室喷孔数为偶数对湍流比无影响,奇数则对湍流比影响较大;预燃室喷孔数对湍动能影响较小;预燃室喷孔数对主燃室空燃比影响不大;预燃室喷孔数减少,可以提升缸内混合气流速。

The pre-combustion chamber combustion system model was meshed using CONVERGE software,and key parameters were set to study the effects of the number of pre-combustion chamber spray holes on tumble flow,turbulent kinetic energy,air-fuel ratio,and cylinder gas mixture velocity.The results show that before the end of the intake stroke,the number of spray holes in the pre-combustion chamber has no effect on the tumble flow.When the valve is closed,the even number of pre-combustion chamber spray holes has no effect on the tumble flow,while the odd number has a greater im-pact on the tumble flow.The number of pre-combustion chamber spray holes has little influence on turbu-lent kinetic energy.The number of pre-combustion chamber spray holes has little influence on the air-fuel ratio in the main combustion chamber.The reduction of the number of pre-combustion chamber spray holes can increase the speed of the gas mixture in the cylinder.