software

I've met some strange problems implementing umat. To speak in short, it's parallel degradation, which means when run in serial mode, everything is OK, there's no failure of equilibirium iteration and therefore no cut back, but when switch to parallel mode, there are random cut backs. I checked the process by outputing results to files and found very bizarre phenomenon, the data changes when transfering from the subroutine called to its caller. For example, if the main program calles sub(a), and in sub a is specified intent(out).

hello

I works with subroutins in ABAQUS.

I  have written a vuhard subroutin and I have some problems.

who  does work with this subroutin that can help me?

With regards

babaeeian 

I simulate a metal foam microstructure in abaqus but now in material property I dont know which kind of material can I use?

For example I used elasticity and plastic(crushable foam) or elasticity and plastic(isotropic hardening) ?

I calculated an example of unaxial tension using GTN model offered by Abaqus. I followed all the instructions found in CAE User's and Analysis User's manual in Abaqus documentation. No error or warning was issued but the result seemed ridiculous, since VVF, VVFG and VVFN keeped 0 throughout the process while equivalent plastic strain keeped increasing(which showed the material had come into plastic deformation). I don't know what went wrong, looking forward to you reply.

Hi all

 I am modeling a truss in fire conditions, using ISO 835 fire for it. Now I have included some imperfections on the braces(L/1000) and I would like to know how to run this type of analysis(RIKS)

I used normally two steps, one to define the load on my truss and the second to import the temperatures as a predefined field. At this moment I do not know ho to modify my model steps in order to reach the solution. My temperature analysis takes 30 min and I cannot add time to a riks analysis

Hi guys，

    Is there anybody use PATRAN and NASTRAN to simulate rotor-bearing sysytem.

After modeling the shat and meshing it, I don't know which element type can be used to 

analysis the bearing than contain cross stiffness and damping  coefficients.

The following is an exmple:

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