The NASTRAN-specific Command Environment

The interface program works in conjunction with a NASTRAN-specific command environment. This environment is activated via the command 'PROPERTY FE-PROG NASTRAN' and is used to prompt the user for loading conditions and material and physical property definitions. The environment variable FG_PRE_INT can be used to make NASTRAN the default environment for all models.

It is important to note that if the analysis environment is changed after material properties, physical properties or loads have been defined in the FEMGEN model, then these will be lost.

In addition the resource file can be used to customise the program to NASTRAN. The relevant lines in the FEMGV Resource file 'femsys.ini' are shown below:

     
#
# This is a FEMGV Resource file. 
#
# Related Files: 
#
# fgvstr.str :- FEMGV startup file used to set environment variables
# FGVSYN.SYN :- Synonym file for command macros and hot keys.
#                                  
# Customised Analysis Environments.
# =================================
# 
# Use these settings in conjunction with environment variable
# FG_PRE_INT in the startup file. Note that more
# than one analysis package may be defined here if desired.
#
# NASTRAN Resources:
#
# Set default element variants.
#
Femsys.nastran-variant.all.BE2  : BAR
Femsys.nastran-variant.all.TR3  : TRIA3-PS
Femsys.nastran-variant.all.TR6  : TRIA6-PS
Femsys.nastran-variant.all.QU4  : QUAD4-PS
Femsys.nastran-variant.all.QU8  : QUAD8-PS
Femsys.nastran-variant.all.PE6  : PENTA
Femsys.nastran-variant.all.P15  : PENTA
Femsys.nastran-variant.all.HE8  : HEXA
Femsys.nastran-variant.all.HE20 : HEXA
Femsys.nastran-variant.all.P-EL : CONM2
#
# Set NASTRAN degree of freedom names.
#           
Femsys.nastran-dofname.internal.1 : X
Femsys.nastran-dofname.internal.2 : Y
Femsys.nastran-dofname.internal.3 : Z
Femsys.nastran-dofname.internal.4 : ROTX
Femsys.nastran-dofname.internal.5 : ROTY
Femsys.nastran-dofname.internal.6 : ROTZ
#
# End of Resource File
#

The FEMGEN/FEMVIEW 2.3 commands used with previous versions of the Interface Program are still available. Attention is drawn to the new FEMGV commands that may be useful to NASTRAN users. The following gives some examples of these new commands, (see the FEMGV User Manual for further information).

     
MESHING TYPES S1 QUAD8-PS
MESHING TYPES 6SURFS HEXA
MESHING TYPES 5SURFS PENTA

CONSTRUCT COORDSYS CYLINDRIC CS1 P1 P2 P3
PROPERTY LOAD FORCE LO1 S1 100 1
PROPERTY ATTACH LO1 CS1

CONSTRUCT SCURVE SC1 SURFACE LINE L1 ELIPSE 10
PROPERTY ATTACH LO1 SC1

CONSTRUCT LMASK LM1 SURFACE .2 .8 .2 .8
PROPERTY ATTACH LO1 LM1

PROPERTY BOUNDARY CONSTRAINT L1 XSYMM

UTILITY TABULATE FE [NASTRAN] BE2 

UTILITY GRAPH SCURVE SC1

LABEL MESH TYPES 

LABEL OPTIONS CONSTRNTS TEXT ON