Sometimes, during the course of doing what you might have thought was a routine simulation, you realize that you are doing something that didn’t used to be routine. In fact, it may have been impossible without advances in software and hardware in recent years.
Recently, DRD was conducting stress simulation for a casting assembly from Davis Tool & Die of Fenton, MO. As the geometry was meshed and examined, small details of the casting continued to become evident and additional refinement was needed. As seen in the images below, the model became quite large.
Missing a stress concentration was not left to chance and the model was simply refined to capture any stress risers. The model was solved, postprocessed, and documented on a commodity PC workstation running a Windows operating system (dual 12-Core processors and 192 GB of RAM available). Now for some statistics:
21.8 Million Elements
33.1 Million Nodes
99.3 Million Degrees of Freedom!
This was a single analysis that solved in 103 minutes. In previous years, to get this kind of detail from a large assembly with lots of small important features, a coarse model would have been solved and then multiple submodels that focused on particular fillets or sections of the model would have been needed.
Another scenario would have been where only single parts would have been solved and the resultant forces from one component mapped onto another. While not overly difficult, these techniques require lots of extra checking of results and file management to make sure nothing is missed. It can be a very tedious process. It is much easier and faster for the end user if a single model can be solved in one pass.
The ANSYS Mechanical mesher and solver have greatly improved over the past few releases to allow what was not possible before to become routine today on commodity Windows PCs. Sometimes it’s easy to lose sight of this.