I also agree with Dan. Converting from FORTRAN to C can be extremely difficult or almost impossible in some cases.
>>FORTRAN is almost as simple as BASIC in many respects.
Top of the line Finite Element Analysis software like ANSYS and NASTRAN are written in FORTRAN. All computationally...
Just to update the followers of this thread. The in-plane rotational stiffness is creating singularities. This can be fixed by using Allman stiffness or switching to 93's. This way the solution is not very much dependant on the upgeom amplitude as well. Thanks Drej, TGS4.
Thanks for the reply Drej.
1. Yes, I ran the eigen value analysis and used the displacements to update the geometry.
2. Yes. The buckled shape is as expected. The loading and end conditions are a bit complex but for the same plate and simpler loading the eigen value results compares favourably...
Sorry about that.
1. nlgeom is on. Non-linear buckling.
2. No plasticity.
3. No arc-length method.
autots is on.
lnsrch is on.
shell 63 used with keyopt(2)=1 with consistent tangent stiffness matrix.
Thanks again.
I am doing an eigen buckling analysis of a plate followed by non-linear buckling. I am using upgeom to provide an imperfection. The problem is with different amplitude factors for upgeom, my buckling load changes significantly. The thickness of my plate is 10mm so I thought a unit factor is good...
I guess there is no direct solution to this, you can open a command file and write the parameter there and read it back from the main macro, second option is to save the parameters by parsav and resume it in the main model by parres. But this may have some unwanted consequences (i.e. overwriting...