GPFORCE

I/O Options and Subcase Information Entry Used to request grid point force balance output for all subcases or individual subcases, respectively.

It can also be used to request grid point charge output for Structural Analysis with piezoelectric materials. For more information, refer to Piezoelectric Analysis in the User Guide.

Format

GPFORCE (format_list, elem, form, peakoutput, modal, use, SUBSYS, NLOUT) = option

Definitions

Argument Options Description
format <H3D, OPTI, PUNCH, OP2, PLOT, HDF5, blank>

Default = blank

H3D
Results are output in Hyper3D format (.h3d file).
OPTI
Results are output in OptiStruct results format (.gpf file).
PUNCH
Results are output in Nastran punch results format (.pch file).
OP2
Results are output in Nastran output2 format (.op2 file) 9
PLOT
Results are output in Nastran output2 format (.op2 file) when PARAM,POST is defined in the Bulk Data section.
HDF5
Results are output in the Hierarchical Data format, Version 5 (.h5 file). 10
elem (H3D only) <ELEM, NOELEM>
ELEM (Default)
GPFORCE results in the H3D output file includes element contributions.
NOELEM
GPFORCE results in the H3D output file will not include element contributions. However, the TOTAL value for each GRID includes the element contributions.
form <REAL, IMAG, PHASE>

Default = REAL

REAL, IMAG
Provides rectangular format (real and imaginary) of complex output.
PHASE
Provides polar format (phase and magnitude) of complex output.
peakoutput <PEAKOUT>

Default = blank

If PEAKOUT is present, only the filtered frequencies from the PEAKOUT card will be considered for this output.
modal <MODAL>

Default = blank

If MODAL is present, grid point forces of the structural modes and residual vectors are output to the PUNCH and OUTPUT2 files for Modal Frequency Response and Transient Analysis.
use <FBD>

Default = blank

If FBD is present, all the necessary output (SPCFORCE, MPCFORCE, and OLOAD) required for FBD will be triggered automatically.
SUBSYS <SUBSYS_ID>

No default

ID of the subsystem.

When used along a subsystem definition, this option generates an individual result file for each subsystem with results for that subsystem only.

For more information, refer to the SET Bulk Data Entry.
NLOUT <NLOUT ID>

No default

ID of the NLOUT Bulk Data Entry.

For more information, refer to Comment 3 in the NLOUT Bulk Data Entry.

option <YES, ALL, NO, NONE, SID>

Default = ALL

YES, ALL, blank
Grid point force balance is output for all elements.
NO, NONE
Grid point force balance is not output.
SID
If a set ID is given, grid point force balance is output only for nodes listed in that set.

Comments

  1. When a GPFORCE command is not present, grid point force balance is not output.
  2. GPFORCE output is available for the following solution sequences:
    Solution Sequence
    Output Formats
    Static Analysis
    H3D, OP2, PCH, OPTI
    Normal Modes Analysis
    H3D, OP2, PCH
    Direct Frequency Response Analysis
    H3D, OP2, PCH, OPTI
    Modal Frequency Response Analysis
    H3D, OP2, PCH, OPTI
    Direct Transient Response Analysis
    H3D, OP2, PCH, OPTI
    Modal Transient Response Analysis
    H3D, OP2, PCH, OPTI
    Nonlinear Transient Response Analysis
    H3D, PCH
  3. The form argument is only applicable for Frequency Response Analysis. It is ignored in other instances.
  4. Multiple formats are allowed on the same entry; these should be comma separated. If a format is not specified, this output control applies to all formats defined by the OUTPUT command, for which the result is available.
  5. Multiple instances of this card are allowed. If instances are conflicting, the last instance dominates.
  6. For optimization, the frequency of output to a given format is controlled by the I/O option OUTPUT.
  7. GPFORCE in .op2 output can only be post-processed with the Free Body Diagram (FBD) tools in HyperMesh/HyperView.
  8. GPFORCE in .h3d output can be used for the Load Transfer Path Analysis with NVH Director. It is only available for Linear Static, Frequency Response, and Acoustic Analyses. An H3D file written with GPFORCE with "use=FBD" (GPFORCE(FBD)) can be used for FBD in HyperView.
  9. format=OUTPUT2 can also be used to request results to be output in the Nastran output2 format (.op2 file).
  10. The HDF5 output is printed to a .h5 binary results file. For details of the supported analysis types and elements when the .h5 output format is requested, refer to the .h5 file.