There are two ways to find the material constants for hyperfoam model. The constants/coefficients will be written to .dat file.
1) Using GUI
– Right click on the Job > Edit Job > General
– Under General tab mark the print model definition data
2) If you are running .inp file directly then you need to do the following editing in the .inp file
Level: Job
*Preprint, echo=NO, model=YES, history=NO, contact=NO
by given model=YES , you will be able to output the material constants in the .dat file.