I really thank you very much. I only want to take my results from start to the end. I attached here my load curve. I want the calculate the stresses at the spesific times.
Yes. Only 1 surface load and no constraints on the head. I want to apply a dynamic force to the head. I attached the load curve. The force begins to hit at the time 0,00207 s. And i started to run the calculation at that time to decrease the simulation duration.
The warning message "** Warning: element 3091 in part 7: determinant =-.26223249E-01<= DETTOL!" is related to the bad element shape. If the element shape is too bad at the very beginning,somehow some deformation will result in too small deternimant. Actually, the mesh in part 6 and part 7 is not good. Especially in the impact area. Finer mesh for part 6 and part 7 is prefered. However, even the current mesh size make the model too large for my computer to handle easily. You might to enlarge the mesh size the other parts which is not so important.
But today i suppressed both parts 6 and 7 and i got the same error in parts 8 and 9. I think there is a convergence problem. The time steps are too small. I tried to set a constant time step but that time the program ended with no result.
Well. It seems that this kind of warning message happens after a convergent step, and the following step has a half step size. In this case, the warning message might be related to the trial solution based on the the last convergent step. And the code automatically cut time step.