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本文对某型号内燃机气道稳态流动和缸内气流运动特性进行了研究.气道流动特性稳态计算结果与气道稳流试验结果相吻合,流动特征参数偏差在3%左右.瞬态计算结果表明,在进气行程初期,缸内涡流和湍流迅速增强,随后涡流变化缓慢,而湍流强度迅速下降.在气门叠开时,存在进气和排气回流现象.进气时,进气阀边缘处是缸内气体最大速度出现位置,气门最大升程时该处速度达到134.4 m/s;切向气道缩口处最大速度高达134.7 m/s,此处存在一定的进气节流损失.
In this paper, steady-state flow and in-cylinder airflow characteristics of a certain type of internal combustion engine are studied.The steady-state calculation results of the air-flow characteristics are in good agreement with the results of the steady-state airway test, and the deviation of flow characteristic parameters is about 3% The results show that at the beginning of intake stroke, the swirl and turbulence in the cylinder are rapidly increased, and then the eddy current changes slowly and the turbulence intensity drops rapidly. When the valve is open, there is intake and exhaust backflow phenomenon. At the edge of the cylinder, the maximum velocity of gas in the cylinder appeared, and the maximum speed reached 134.4 m / s at the maximum lift of the valve. The maximum velocity of the tangential airway was 134.7 m / s. There was a certain intake throttle loss .