The issue is that the result file job.frd is overwritten in a restart job. I am wondering if there is a way to append subsequent result to the previous one?
I guess will save disk space if all the result are put into a single file, since the mesh information is not duplicated.
You can only control this with the OVERLAY parameter:
In order to prevent the restart file to become too big, the user can specify the parameter OVERLAY for the *RESTART,WRITE combination. In that case every new step being written to the restart file will delete all previous information. So only the last step written to file will be available for any subsequent reuse by a *RESTART,READ command.
And:
The results will be stored in binary format in file “jobname.rout”. Any existing file with this name will be deleted prior to the first writing operation.