Initial Conditions Definition using Output Files

The output files can be used to impose initial conditions on shell or solids in subsequent runs through the keyword /INISTA.

Both Runname_run#.sty and Runname_0000.sty files are required.

The following variables can be initialized:

For nodes:
  • Initial coordinates
  • Initial velocities
For solids:
  • Plastic strains
  • Internal energy
  • Density
  • Stresses (if energy and density are provided, pressure is overwritten)

For solid elements, initial conditions are compatible with Material Laws 1, 2, 3, 4, 6, 36 and user laws, if the formulation is incremental.

For shells:
  • Stress
  • Strain
  • Plastic strain
  • Energy
  • Thickness
  • Hourglass
  • Forces

For shell elements, initial conditions are compatible with Material Laws 1, 2, 36 and user laws.

The Runname_run#.sty file is defined with the /INISTA keyword in the Radioss Starter.

The Runname_0000.sty file is required to associate the data given in Runname_run#.sty files with node and element identification.

The model used to write the Runname_0000.sty or Runname_run#.sty files can be identical or different from the current model (though it must always have a different root name).

If the models are different, the Runname_0000.sty must contain less elements than the Runname_0000.rad file.

Strain tensor for shells is only needed for /MAT/LAW36 (PLAS_TAB) with tension failure option or users law.

/INISTA Example

# ISRTYnnn
#     IBAL IOUTYYfmt  IOUTYnnn
         0         0         0
#     IPRI               IGTYP     IOUTP    IOUTYY   IROOTYY     IDROT
         0                   0         1         0         0         0