dynaform求解出现错误

dynaform求救出现错误1.是管型件，采用热成型工艺
2.不是成型阶段出现，是冷却阶段出现，在冷却的第6s时 出现
3.想问下 怎么处理，求大神指教
提示due to the negative jacobin
failed element report time =8.153E+0
number of failed solid element= 0
number of failed beam element= 0
number of failed shell element= 4
number of failed tshell element= 0
shell element 144198 failed at time 8.153E+0
...........