PRESSURE

I/O Options and Subcase Information Entry Used request displacement and pressure output for all subcases or individual subcases, respectively.

Displacement and pressure output is currently supported for Frequency Response Analysis and Darcy Flow Analysis.

Format

PRESSURE (sorting, format, form, rotations, type) = 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 Frequency Response Analysis subcases. 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. 8
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, PATRAN, HG, APATRAN, PLOT, 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 (.disp file).
PUNCH
Results are output in Nastran punch results format (.pch file).
OP2
Results are output in Nastran output2 format (.op2 file).
PATRAN
Results are output in Patran format (multiple files).
HG
Results are output in HyperGraph presentation format (_freq.mvw file and _tran.mvw file) - refer to OUTPUT keywords HGFREQ and HGTRANS.
APATRAN
Results are output in Alternative Patran format (multiple files).
PLOT
Results are output in Nastran output2 format (.op2 file) when PARAM,POST is defined in the Bulk Data section.
If PARAM, POST is not defined in the Bulk Data section, this format allows the form for complex results to be defined for XYPUNCH output without having other output.
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 HyperMesh output format.
REAL or IMAG
Provides rectangular format (real and imaginary) of complex output. 9
PHASE
Provides polar format (magnitude and phase) of complex output. Phase output is in degrees. 9
BOTH (HM only)
Provides both polar and rectangular formats of complex output.
rotations <ROTA, NOROTA>
ROTA
Rotational displacement results are output. Only works with H3D and HM output streams. Rotations are always output with translations for other output streams.
NOROTA (Default)
Rotational displacement results are not output. Only works with H3D and HM output streams. Rotations are always output with translations for other output streams.
option <YES, ALL, NO, NONE, SID>

Default = ALL

YES, ALL, blank
Displacement is output for all grids.
NO, NONE
Displacement is not output.
SID
If a set ID is given, displacement is output only for grids listed in that set.

Comments

  1. When PRESSURE command is not present, displacement or pressure is not output for frequency response subcases. Similarly, nodal flow pressure output is disabled by default for Darcy Flow Analysis. Use of PRESSURE I/O Entry activates this output for nodal flow pressure in Darcy Flow.
  2. PRESSURE I/O Entry can be used to output displacement and pressure for Frequency Response Analysis. Additionally, PRESSURE I/O Entry is used to output nodal flow pressure in Darcy Flow Analysis subcases. This output is currently only supported in H3D format. This is output as “Grid Pressure of Flow(s)” in H3D files and can be visualized in HyperView.
  3. The forms BOTH and COMPLEX do not apply to the .frf output files.
  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. Refer to Results Output for information on which results are available in which formats.
  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. In previous version 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.
  7. Rotation results are output in radians.
  8. 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.
  9. Results in binary format (.h3d or .op2) are always output in PHASE/MAG form, regardless of the options specified in the FORM field. The corresponding post-processors (HyperView/HyperGraph) can easily convert the PHASE/MAG format to the required formats. Results in ASCII formats are output in the specified/requested FORM.
  10. format=OUTPUT2 can also be used to request results to be output in the Nastran output2 format (.op2 file).