Translating Nastran DMIG Matrix Data in Output2 Binary Files to an Abaqus Binary SIM File

Overview

The Nastran matrix data can be in one or two binary Output2 files. The DMIG matrix data are assumed to be written to an Output2 file using a command as follows:

ASSIGN OUTPUT2='jobname_matrixdata.op2',UNIT=30
…
EXTSEOUT(STIFFNESS,
         MASS,
         DAMPING,
         K4DAMP,
         LOADS,
         ASMBULK,
         EXTBULK,
         EXTID=10,
         DMIGOP2=30)

The nodal coordinate data may be in a second Output2 file, created with a command as follows:

ASSIGN OUTPUT2='jobname.op2',UNIT=12
…
DISP(PLOT) = ALL
…
PARAM,POST,-2

These Output2 files are referenced by the op2file1 and op2file2 options. The use of op2file2 is optional. Using the file names from the example above, you specify the command line options as follows:

op2file1=jobname_matrixdata.op2 op2file2=jobname.op2

The op2target option determines the type of matrix data to create. The matrix data can be translated to:

• a partial Abaqus input file with a MATRIX INPUT representation of the matrix data,
• a SIM file structured as if it were created from a MATRIX GENERATE step in an Abaqus input file, or
• a SIM file equivalent to that resulting from an Abaqus analysis with a SUBSTRUCTURE GENERATE step.