某缸盖热机疲劳分析

利用AVL-Fire对缸内工作过程和水套进行CFD分析,得到缸内及水套壁面的热边界条件,通过有限元技术把对流热边界耦合至固体传热的计算中,达到共轭传热的目的.分别完成了机械载荷和温度载荷下的缸盖应力计算,结合经过温度修正的材料特性,计算得到疲劳安全因子分布.分析结果表明:对于缸盖疲劳而言,热载荷贡献明显大于机械载荷;缸盖设计满足使用要求.

The Thermal Mechanical Fatigue Analysis on a Cylinder Head

CFD analysis was carried out on the in-cylinder and water jacket with AVL-Fire.In order to achieve the conjugate heat transfer,the convection thermal boundary conditions were coupled to the calculation process of the solid heat conduction with FE technology.The calculation of the cylinder head stress under the mechanical and thermal load was done.Finally,the mechanical-thermal fatigue integrating the material properties corrected by temperature,and the access to the safe factor,were analyzed.The results have shown that,in terms of the fatigue of cylinder head,the contribution of thermal load is noticeably greater than the mechanical load.The results have also shown that the cylinder head design meets its work demand.