GPFORCE

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

Format

GPFORCE (format_list, 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). 12 OPTI Results are output in OptiStruct results format (.gpf file) in the global coordinate system. For nonlinear static and nonlinear transient analyses, the OPTI file (.gpf file) is written on-the-fly. 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
`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`	<Vector, FBD, Scalar> Default = Vector	Vector If vector is present, GPF total output is triggered. The result are output in the global coordinate system. FBD If FBD is present, all the necessary output (SPCFORCE, MPCFORCE, and OLOAD) required for FBD are triggered automatically. This output is similar to Vector output, but FBD is in the basic coordinate system. Scalar If Scalar is present, GPF total output is triggered (legacy option). 12
`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 grids and 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

When a GPFORCE command is not present, grid point force balance is not output.
GPFORCE output is available for the following solution sequences:

Solution Sequence

Output Formats

Static Analysis 11

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

Implicit Nonlinear Static and Nonlinear Transient Analysis

H3D, OP2, PCH, OPTI
The form argument is only applicable for Frequency Response Analysis. It is ignored in other instances.
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.
Multiple instances of this card are allowed. If instances are conflicting, the last instance dominates.
For optimization, the frequency of output to a given format is controlled by the I/O option OUTPUT.
GPFORCE in .op2 output can only be post-processed with the Free Body Diagram (FBD) tools in HyperMesh/HyperView.
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.
format=OUTPUT2 can also be used to request results to be output in the Nastran output2 format (.op2 file).
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.
GPFORCE results are also available in Hyper3D (.h3d) and OPTI formats (.gpf) for linear static analysis preloaded with a large displacement analysis.
GPFORCE(H3D) writes the results in the global coordinate system at grids, which is the combination of all the systems and thus, not necessarily unique. GPFORCE(H3D, FBD) writes the results in the unique basic coordinate system (refer to Coordinate Systems in User Guide). GPFORCE(H3D, Scalar) remains as the legacy option. This option outputs GPF Total.
Figure 1. GPFORCE Output Label in H3D File for Different Options
GPFORCE 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.