汽油机活塞组件的摩擦损失研究

基于一台三缸涡轮增压汽油机,分析了曲轴位置、连杆比以及发动机运行工况对活塞组件摩擦损失的影响。研究结果表明,在连杆比一定时,随着曲轴偏置量从0mm增加到15mm,活塞组件的摩擦损失量减小,在曲轴偏置为15mm时,活塞组件的摩擦损失量减少达到最优。然而,当曲轴偏置量增加到20mm后,活塞组件的摩擦损失量有所增加。当曲轴偏置量一定时(15mm),随着连杆比从0.29减小到0.25,活塞组件的摩擦损失逐渐减少;随着连杆比从0.29增加到0.31,摩擦损失有所增加。当转速从1000r/min增加到2000r/min时,活塞组件的摩擦损失有所增加,而随着转速一直增大,摩擦损失量有所降低。当转速在1000r/min时,随着负荷的增大,摩擦损失有所改善。而在3000r/min时,负荷对摩擦损失的影响并不明显。最后,对连杆比为0.25和0.31时,发动机不同运行工况下的摩擦损失进行了综合协同优化分析。

The Study on Friction Loss of Piston in Gasoline Engine

Based on a three-cylinder turbocharged gasoline engine,this paper analyzes the relationship of friction loss with different crankshaft offset and crank ratio.The results show that,when the crank ratio constant,as the crankshaft offset increases from 0mm to 15mm,the friction loss of the piston decreases,the friction loss of piston is optimal at 15mm.When the crankshaft offset increases to 20mm,the friction loss of the piston increases.When the crankshaft offset is constant(15mm),the friction loss of the piston gradually decreases as the crank ratio decreases from 0.29 to 0.25;As the crank ratio increases from 0.29 to 0.31,the friction loss increases.When the rotating speed increases from 1000r/min to 2000r/min,the friction loss of the piston assembly increases,while as the rotating speed increases,the friction loss decreases.When the speed is at 1000r/min,the friction loss is improved as the load increases.At 3000r/min,the impact of load on friction loss was not obvious.Finally,a comprehensive collaborative optimization analysis is made for the friction loss under different operating conditions when the crank ratio is 0.25 and 0.31.