How can I specify the temporary directory (where all of the scratch files are written) to run OptiStruct jobs?

In an OptiStruct input, the complete path to the temporary directory (which has enough disk space for the scratch files) can be entered on the TMPDIR card. The TMPDIR card is available in HyperMesh in the control cards panel.

Also, please note that when a temporary directory is specified, it is important to verify that the directory has correct read and write permissions.