关键词: 天然气发动机, 气流运动, 燃烧过程

Abstract: The airflow motion in cylinder and its influence on the combustion process for the natural gas engine were studied through numerical simulation technology. Two combustion systems with different intake ports were simulated. The results of the numerical simulation show that the final momentum near TDC and the center of the vortex flow are influenced by the airflow motion formed during the intake process; the vortex flow can be maintained to TDC, and the main reason for the increase in the turbulence intensity is that the large scale turbulence breaks up into very small scale vortex flow during the terminal compression stroke; it is helpful for the even radial spreading of the flame that the center of the vortex flow in cylinder is close to the cylinder center.

Key words: airflow motion, combustion process , natural gas engine