滚流对火花点火式发动机性能的影响

火花点火发动机气缸内空气运动的滚流与涡流一样，都可以增加燃烧室中的湍流强度，提高火焰传播速度和燃烧速率，从而改善燃烧过程，提高发动机的动力性能。本文详细介绍了滚流形成机理和影响滚流的气道参数。对2气门TJ376Q发动机的试验结果表明：新进气道的设计提高了缸内空气运动的滚流强度和流量系数，通过进气系统的优化，可以增加发动机最大转矩和最大功率输出，试验在电控燃油喷射下精确控制燃油，降低了最低燃油消耗率。

Effect of In-cylinder Tumble Motion on Performance of a Gasoline Engine

In-cylinder tumble motion, similar to the swirl motion, can increase the turbulence intensity and result in higher flame speed and combustion rate in spark ignition engine. The principle of tumble motion and the effect of inlet port parameters on features of tumble are described in this paper. Tests on a two valve TJ376Q gasoline engine showed that with inlet port shape modification, the engine torque and power outputs were increased due to the enhancement of in-cylinder tumble motion and flow coefficient. The optimization of inlet system configuration and the use of electronically controlled fuel injection lead to the improvement of engine performance and the reduction of fuel consumption.