基于ANSYS软件的496ZQ柴油机曲轴结构性能研究

Structural Performance Research on 496ZQ Diesel Crankshaft Based on ANSYS Software Platform

利用ANSYS软件研究496ZQ柴油机危险载荷下曲轴的应力、应变及其分布,研究不同重叠度对曲轴的应力的影响,并对曲轴进行模态分析。研究表明,曲轴的应力和应变满足设计要求,不会发生弯曲疲劳破坏。但是,在主轴颈尺寸为72 mm、连杆轴颈尺寸为63 mm、重叠度为1.16时,连杆轴颈和主轴颈圆角处的最大应力都比较小。自由模态下,最大相对位移量1.03出现在第9阶振型上,对应的频率为1 306 Hz,避开了曲轴的固有频率,曲轴在工作时不会发生共振;约束模态下,曲轴的最大相对位移偏移量1.717出现在第8阶振型上,对应的频率为8 478 Hz,曲轴工作时,应该避开此频率,避免发生扭转疲劳破坏。

As one of the most loaded parts,structure performance of crankshaft has a direct effect on the reliability and durability of engine.In this paper,the stress,strain size and distribution under dangerous loads,the influence of different overlaps on the stress and the modal analysis of crankshaft are studied by ANSYS software.The results show that the stress and strain of the crankshaft meet the design requirements,and the bending fatigue failure will not occur.However,when the dimensions of main journal is 72 mm,connecting rod journal is 63 mm and overlap is 1.16,the maximum stress at the circular corner of main journal and connecting rod journal is smaller.In the free mode,the maximum relative displacement of 1.03 appears on the 9th order mode,the corresponding frequency is 1 306 Hz,which avoids the natural frequency of the crankshaft,and the crankshaft will not resonate when it works.In the constrained mode,the maximum relative displacement offset of the crankshaft appears on the 8th order mode,and the corresponding frequency is 8 478 Hz,which should be avoided when the crankshaft is working,so as to avoid torsional fatigue damage.