SPCFORCE

I/O Options and Subcase Information Entry Used to request single-point force of constraint vector output for all subcases or individual subcases, respectively.

Format

SPCFORCE (sorting,format_list,form,type,randompeakoutput,nlout=nloutid, statistics) = option

Definitions

Argument Options Description
sorting <SORT1, SORT2> This argument only applies to the PUNCH format (.pch file) or the OUTPUT2 format (.op2 file) output for normal modes and frequency response. It will be ignored without warning if used elsewhere.
SORT1
Results for each frequency/timestep are grouped together.
SORT2
Results for each grid/element are grouped together. 10
blank (Default)
For Frequency Response Analysis, if grid SET is not specified, SORT1 is used, otherwise, SORT2 is used; for Transient Analysis, SORT2 is used.
format <HM, H3D, OPTI, PUNCH, OP2, PLOT, HDF5, blank>
HM
Results are output in HyperMesh results format (.res file).
H3D
Results are output in Hyper3D format (.h3d file).
OPTI
Results are output in OptiStruct results format (.spcf file).
PUNCH
Results are output in Nastran punch results format (.pch file).
OP2
Results are output in Nastran output2 format (.op2 file). 11
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). 13
blank (Default)
Results are output in all active formats for which the result is available.
form <COMPLEX, REAL, IMAG, PHASE, BOTH>

Default (HM only) = COMPLEX

Default (all other formats) = REAL
COMPLEX (HM only), blank
Provides a combined magnitude/phase form of complex output to the .res file for the HM output format.
REAL, IMAG
Provides rectangular format (real and imaginary) of complex output.
PHASE
Provides polar format (magnitude and phase) of complex output. Phase output is in degrees.
BOTH (HM only)
Provides both polar and rectangular formats of complex output.
random <PSDF, RMS, PSDFC>

No default
PSDF
Requests PSD and RMS results from Random Response Analysis to be output.
Output is available in the .h3d, .pch and .h5 formats. 7
RMS
Requests only the "RMS" result from Random Response Analysis to be output.
Output is available in the .h3d, .pch and .h5 formats. 7
PSDFC
Requests PSD, RMS and RMS (cumulative) results from Random Response Analysis to be output.
In the .h3d and .h5 formats, all the above results are available.
In the .pch format, only PSD and RMS results are available. 7
type <SPARSE, ALL>
SPARSE (Default)
Single-point force of constraint is output only for selected nodes with a component with a magnitude of 1.0E-10 or greater.
ALL
Single-point force of constraint is output for all selected nodes.
peakoutput <PEAKOUT>

Default = blank

 Only the filtered frequencies from the PEAKOUT card will be considered for this output.
nlout <nloutid>

No default

 ID of an NLOUT Bulk Data Entry.

If present, the incremental output control parameters are taken from the referenced NLOUT Bulk Data Entry, instead of the one selected by Subcase Entry NLOUT, when results are written into the *_impl.h3d file. 14
statistics <STATIS, OSTATIS or blank> Statistics of single-point force of constraint vector over time in a Transient Analysis are controlled by this option. 15
STATIS
The statistics of single-point force of constraint vector are output, in addition to regular single-point force of constraint output at each timestep.
OSTATIS
Only the single-point force of constraint vector statistics is output.
blank (Default)
option <YES, ALL, NO, NONE, SID>

Default = ALL
YES, ALL, blank
Single-point force of constraint is output for all nodes.
NO, NONE
Single-point force of constraint is not output.
SID
If a set ID is given, single-point force of constraint is output only for nodes listed in that set.

Comments

  1. When an SPCFORCE command is not present, single-point force of constraint vector is not output.
  2. Single-point force of constraint values are highly dependent on mesh density and type of elements used.
  3. For Modal Frequency Analysis, residual forces are zero only in modal space. Therefore, the single-point force of constraint vector may not be accurate unless all modes are used in the modal solution. When all possible modes in the model space are used, the Modal Frequency Analysis solution should match the Direct Frequency Analysis solution.
  4. When single-point force of constraint is calculated, the reaction force summary, the load summary, and the strain energy residuals for the affected subcases are written to the .out file.
  5. The form argument is only applicable for Frequency Response Analysis. It is ignored in other instances.
  6. The forms BOTH and COMPLEX do not apply to the .frf output files.
  7. 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. See Results Output by OptiStruct for information on the results available and their respective formats.
  8. Multiple instances of this card are allowed. If instances are conflicting, the last instance dominates.
  9. For optimization, the frequency of output to a given format is controlled by the I/O option OUTPUT. In previous versions of OptiStruct, a combination of the I/O Options FORMAT and RESULTS were used. This method is still supported, but not recommended as it does not allow different frequencies for different formats.
  10. In general, HyperView does not recognize the SORT2 format for results from the .op2 file. When results are output only in SORT2 format (<Result Keyword> (SORT2, OUTPUT2, ...)), the results are written by OptiStruct into the .op2 file in SORT2 format, but when the .op2 file is imported into HyperView, the results in SORT2 format are not recognized. Therefore, the SORT1 option is recommended for results output in OUTPUT2 format and SORT2 option is recommended for results output in PUNCH format.
  11. format=OUTPUT2 can also be used to request results to be output in the Nastran output2 format (.op2 file).
  12. When SPCF/SPCFORCE is requested for steady-state heat transfer subcases, the power at SPC degrees of freedom will be calculated.
  13. 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.

    For details about the old HDF5 format (.hdf5), refer to PARAM, HDF5 and .hdf5 file.

  14. nlout=<nloutid> applies only to implicit nonlinear subcases.
  15. Single-point force of constraint statistics are supported for Direct and Modal Linear Transient Analysis.

    Only H3D output is supported for single-point force of constraint statistics.

    The following statistics over time are output for Transient Analysis when STATIS or is specified.
    Statistics
    Supported SPCFORCE Result Types
    Minimum and Time of Minimum
    X-component, Y-component, Z-component
    Maximum and Time of Maximum
    Magnitude, X-component, Y-component, Z-component
    Absolute Maximum and Time of Absolute Maximum
    X-component, Y-component, Z-component
    Arithmetic Mean, Root Mean Square (RMS), Variance, and Standard Deviation
    Magnitude, X-component, Y-component, Z-component
    The SPCF statistics can be viewed in HyperView after loading the H3D file, under Statistics over time option at the end of the timestep list in the Results Browser. Then, various statistics can be chosen from the sub-menu under SPCF Forces (Statistics) (s).


    Figure 1.