冲程缸径比对汽油机缸内流场影响的研究  

A Study on the Effect of Stroke-to-Bore Ratio on Gasoline Engine's Flow Field

作　　者：高莹[1] 谢天驰 门欣 徐英健 费孝恒 Gao Ying;Xie Tianchi;Men Xin;Xu Yingjian;Fei Xiaoheng(Jilin University,State Key Laboratory of Automobile Simulation and Control,Changchun 130025)

机构地区：[1]吉林大学汽车仿真与控制国家重点实验室,长春130025

出　　处：《汽车工程》2018年第9期1014-1020,共7页Automotive Engineering

基　　金：国家科技支撑计划(2015BAG05B00)资助

摘　　要：为探究冲程缸径比对汽油机缸内流场的影响,保证其它条件相同,将某三缸进气道喷射汽油机模型的冲程缸径比改为0. 7和0. 9(分别设为方案1和方案2),原机计算模型冲程缸径比为1. 05(设为方案3)。利用AVL-Fire软件对3种计算方案在2 000r/min低负荷工况和3 800r/min全负荷工况下的进气及燃烧过程进行瞬态数值模拟计算。对比不同计算方案的缸内速度场、湍动能场和瞬时放热率。结果表明,在一定范围内,适当增加冲程缸径比,能够提高缸内滚流强度,从而使点火时刻湍流强度增大且分布良好,瞬时放热率更高,燃烧速度更快。To investigate the effect of stroke-to-bore ratio on in-cylinder flow field, the stroke-to-bore ratioof a three-cylinder port fuel injection gasoline engine model is changed to 0, 7 and 0, 9 （set as scheme 1 and scheme2） with the other conditions the same, and the stroke-to-bore ratio of the original engine is 1, 05 （set as scheme 3）.Transient numerical simulation on the intake and combustion process of the three computational schemes at 2000r /min low load and 3800r / min full load is conducted using the software AVL-Fire. The velocity field, turbulent kineticenergy field and heat release rate of the three different computational schemes are compared. Results show that with-in reasonable limits, the appropriate increase of stroke-to-bore ratio can enhance the intensity of in-cylinder tumble,and hence improve the intensity and distribution of turbulence at ignition timing, achieving greater heat release rateand faster combustion.

关 键 词：汽油机 冲程缸径比 滚流 湍动能 数值模拟 

分 类 号：U464.171[机械工程—车辆工程]