A- The error message “error in transferring Special loads”
- This error occurs when the entities of the BC (boundary conditions) applied to and the mesh don’t match. This usually happens with shell mesh and beam mesh, where the original CAD model has solid geometries, but different mesh type is used for simulation studies. Check all BC with mesh shown. If the BC is applied on entities don’t exist in the mesh, load transfer will fail. Another way is to suppress BC one by one to verify.
- Second reason the error occurs is small features ignored in the mesh. If the mesh size is too large for the small feature, and there is no mesh failure, the mesh could ignore the small features. If a BC is applied on the small feature, the load transfer will also fail.
B- How to successfully mesh?
- Mesh failure is common if only global size is used, because small features/components may not take the global mesh size, or the mesh size tolerance is too small.
1- Check if the small features/components are necessary in the study.
2- Check if increasing mesh tolerance will fix the problem. Default is 5% of the mesh size.
3- Right click on the mesh and go to failure diagnostics. This will tell you which part/feature/face failed. Apply mesh control on these entities. If necessary, open the component on its own, and mesh individually see what mesh size is required.
4- incompatible mesh, and enable “improve accuracy for no penetration contacting surfaces” if no penetration is involved. Mesh failure can be from the huge size difference between components in contact.
C- What solver should I use?
- If the study has a huge number of elements, it is more efficient to use FFEPlus solver.
- If the study shows “out of core” during solving, it is more efficient to use FFEPlus solver. Out of core means the physical RAM is all used up and hard drive is being used for memory.
- If the study has contacts, bolt connectors, it is more efficient to use Direct Sparse solver.