过盈量对干式缸套变形规律的影响研究

Influence of Interference on Deformation Law of Dry Cylinder Liner

以某干式缸套柴油机为原型,采用有限元仿真的方法,建立了机体、缸盖、缸垫、缸套、螺栓等组合的有限元模型,分别在预紧工况和热机耦合工况下对比研究了施加过盈量前后的气缸套变形规律。研究结果表明:在装配工况下,从缸套顶部至缸套底部,缸套的变形量都逐渐变小,施加了过盈量后的缸套综合变形增加了近两倍,综合变形量最大出现在第四缸上部的290°区域,变形量为19.4μm。在多个载荷的耦合作用下,不同缸爆发时的缸套变形趋势和单独施加螺栓预紧力的变形趋势几乎一致,从缸套顶部至底部,变形量逐渐较小,第二、三缸变形较小,第一、四缸靠近自由端两侧变形较大,最大变形出现的位置从顶部90°方向移动至0°方向附近,变形量为302.8μm。

Based on a dry cylinder liner diesel engine,using the method of finite element simulation,a finite element model is established which is related to the engine body,cylinder head,cylinder cushion,cylinder liner,bolts and so on,and the deformation law of cylinder liner before and after apply the interference was studied under preloaded condition and thermal-mechanical coupling condition.The results of the study show that under assembly conditions,the deformation of the cylinder liner gradually decreases from the top of the cylinder liner to the bottom of the cylinder liner.After the interference is applied,the comprehensive deformation of the cylinder liner increases by nearly twice.The largest comprehensive deformation appeared in the upper part of the fourth cylinder’s 290°area and the deformation is 19.4μm.Under the coupling action of multiple loads,the deformation trend of the cylinder liner when different cylinders burst out is almost the same as the deformation trend of applying bolt preload separately.From the top to the bottom of the cylinder liner,the amount of deformation is gradually smaller,the second and third cylinders have less deformation,the first and fourth cylinders have greater deformation near the free end and the maximum deformation’s occurrence position moves from the top 90°direction to near 0°direction,and the deformation is 302.8μm.