Format of FEMGEN Neutral Output File

      

This Appendix defines the format of file generated by the command UTILITY WRITE NEUTRAL which may be used to write out the geometric and mesh data generated by FEMGEN . This data may then be read and converted into the form required by an analysis program.

(Note that in addition to the neutral file format described here, a set of Fortran callable User Routines is also supported. The use of these enables data to be read directly from the FEMGEN database without recourse to the neutral file. Details of these User Routines are given in a separate manual.)

The structure of the FEMGEN neutral file is essentially the same as that specified in Appendix B but with some additional data sets.

Neutral file use within an analysis specific environment

Note that where an analysis specific environment has been selected (see command PROPERTY FE-PROG program_name), then material property, physical property and loading data cannot necessarily be represented correctly by the neutral file format. This is because in an analysis specific environment the definition of material property, physical property and loading data may have been changed.

Each data set starts with a header of the form:

KEY, OPCODE, Name, IFORMT

To be read with the format:

FORMAT (1X, I4, A1, A6, 61X, I2)

Where:

KEY = data set identification key see Table A.1

OPCODE = 'C' ( create a new data set)

Name = model or data set name

IFORMT = Format indicator 0 = 5 digit node/element number format 1 = 10 digit node/element number format

Notes:

1.

If a node or element number exceeds 99999 the 10 digit format will automatically be used for all node and element numbers. Alternatively environment variable FG_NEU_SIZ can be set to 10 in order to write node and element numbers to the 10 digit format.

Record Type KEY Name

Model Header 1 Model Name

Nodal Coordinate Header 2 --

Element Definition Header 3 --

Part definition 101

Material Definition 20

Physical Properties 102

Constraints 103

Generalised Constraints 104

Elastic Supports 105

Coordinate Systems 107

Concentrated Forces 110

Prescribed Displacements 111

Pressure 112

Temperature 113

Gravity 114

Centrifugal 115