热应力中转换单元问题

xiaovsfeg1

我在做热分析时选的PLANE55和surf151单元，但在之后计算热应力时选择thermal to struc，会出现错误提示，Shape testing revealed that 70 of the 71 new or modified elements violate error limits。To review test results，please see the output file or issue the CHECK command，点proceed后又2出现waring：The ETCHG has changed some element types。please examine not only the KEYOPTs,but also the real constants,material properties,boundary conditions and loadings,and then modify as needed.之后再查看单元类型，就变成PLANE182和SURF153了，我该怎么做啊，谢谢好心人的指导，谢谢。