deform模拟挤压的棘手问题

以前做 deform挤压模拟都能成功，最近做却总在step 1运算前就出现网格重划分、出现负雅可比而停止。三维造型、网格划分、步长等作了很多次的调整，仍然不能解决问题。实在没招，请各位高手指点。先谢了。
Step number is -1
Convergence Criteria for Iterative Solver
V-norm = 5.00E-03 F-norm = 5.00E-02
STEP NUMBER = 1
Eqs. New Profile Ave. Bandwidth
7964 198902 48
DIRECT METHOD
ITERATION VELOCITY RELATIVE VELOCITY RELATIVE FORCE SOLVING TIME
NUMBER NORM ERROR NORM ERROR NORM (SEC)
Program stopped because of bad element shape!
Program stopped because of negative Jacobian!
出现很多如下提示
Warning: Element has negative Jacobian -- Obj.# 1 Element # 96 Vol = 0.00000E+00
535 74.710270 41.934100 95.844160
336 70.000000 40.634310 70.000000
536 70.000000 37.520210 70.000000
425 70.000000 38.698360 70.000000
Stop!--Neg. Jac. after calculation, Element= 347
The initial coord.:
121 73.04001 36.97797 120.27763
74 70.00000 39.28014 119.39750
79 70.00000 35.34189 119.39750
62 70.00000 37.80945 123.15900