EIGVNAME - Filename Prefix Definition
Description
The EIGVNAME command can be used in the I/O Options section to define the prefix to be used for external eigenvalue data files (.eigv).
Format
EIGVNAME = prefix
Argument Description
prefix The prefix to be used for the saving and retrieval of external eigenvalue data files.
The external eigenvalue data file name is of the form <prefix>_#.eigv, where <prefix> is defined here, # is the integer argument of the
EIGVSAVE subcase information entry or one of the integer arguments of the EIGVRETRIEVE subcase information entry.
Comments
1. When an EIGVNAME command is not present, the OUTFILE prefix definition is used. If OUTFILE is not defined, the prefix of the input file is used.
2. Only one occurrence of EIGVNAME is permitted. 3. EIGVNAME must appear before the first subcase.
4. The total length of information on this card is limited to 200 characters (including the card name and spaces between arguments). This data can be on a single line or span multiple continuation lines. See Guidelines for I/O Options and Subcase Information Entries for an example showing how to enter long file names on multiple lines.
5. Prefixes specified on the EIGVNAME card can be arbitrary file prefixes with optional paths appropriate to the operating system (Windows or UNIX). They may be enclosed in quotes (double or single quotes can be used), and either forward slash (/) or back slash (\) characters can be used to separate parts of the path name.
OptiStruct uses the following rules for the EIGVNAME card:
When the argument contains an absolute path of the file (if it starts with "/" on UNIX or a drive letter, such as "D:", on Windows, for example), OptiStruct creates .eigv files at the given location.
When only the file prefix is given (without the path), .eigv files will be created in the current directory, meaning the directory from which OptiStruct has been executed, and NOT in the directory where the input file is located.
When the argument contains a relative path (../filename or sub/filename, for example), .eigv files will be created in a directory relative to where OptiStruct is executed and NOT relative to the directory where the input file is located.
EKE
I/O Options and Subcase Information Entry EKE - Output Request
Description
The EKE command can be used in the I/O Options or Subcase Information sections to request kinetic energy and kinetic energy density output for all subcases or individual subcases respectively.
Format
EKE (format_list, type, dmig, peakoutput) = option
Argument Option Description
format <HM, H3D, PUNCH, OP2, PLOT, blank> Default = blank
HM: Results are output in HyperMesh
results format (.res file).
H3D: Results are output in Hyper3D format
(.h3d file).
PUNCH: Results are output in Nastran punch results format (.pch file).
OP2: Results are output in Nastran output2
format (.op2 file) (see comment 8). PLOT: Results are output in Nastran output2
format (.op2 file) when PARAM, POST is defined in the bulk data section.
blank: Results are output in all active formats for which the result is available.
type <AVERAGE, AMPLITUDE, PEAK> Default = AVERAGE see Comment 7
AVERAGE: In frequency response analysis average energy is output.
AMPLITUDE: In frequency response analysis the amplitude of energy is output.
PEAK: In frequency response analysis the
peak energy is output. This is the sum of AVERAGE and AMPLITUDE.
Argument Option Description
dmig <DMIG,
NODMIG> Default = NODMIG
DMIG: Results are provided for external superelements in the .out file. NODMIG: Results are not provided for external
superelements in the .out file.
peakoutput <PEAKOUT> Default = blank
PEAKOUT: If PEAKOUT is present, only the filtered frequencies from the PEAKOUT card will be considered for this output.
option <YES, ALL, NO, NONE, SID> Default = ALL
YES, ALL, blank:
Element kinetic energy and kinetic energy density are output for all elements.
NO, NONE: Element kinetic energy and kinetic energy density are not output.
SID: If a set ID is given, element kinetic energy and kinetic energy density are output only for elements listed in that set.
Comments
1. When an EKE command is not present, element kinetic energy and kinetic energy density is not output.
2. Initial thermal strain is included in the calculation of kinetic energy and kinetic energy density.
3. Multiple formats are allowed on the same entry; these should be comma separated. If no format is specified, then this output control applies to all formats defined by OUTPUT or FORMAT commands for which the result is available. See Results Output for information on which results are available in which formats.
4. Multiple instances of this card are allowed; if instances are conflicting, the last instance dominates.
5. 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 rec ommended as it does not allow different frequencies for different formats.
6. Type only applies to frequency response analysis.
7. There are three ways to calculate the Element Kinetic Energy in Frequency Response Analysis. They are listed as follows:
Type of Output Formula
Average
Amplitude
Peak
Where,
E = Element Energy
{vr } = Real part of Veloc ity {vi } = Imaginary part of Veloc ity [M
e] = Element Mass
8. format=OUTPUT2 can also be used to request results to be output in the Nastran output2 format (.op2 file).
ENERGY
I/O Options and Subcase Information Entry
ENERGY - Output Request for Geometric Nonlinear Analysis Subcase
Description
The ENERGY command can be used in the I/O Options or Subcase Information sections to request energy output for all geometric nonlinear analysis subcases or individual geometric nonlinear analysis subcases respectively.
Format
ENERGY (format, type) = option
Argument Option Description
format <H3D, blank> Default = blank
H3D: Results are output in Hyper3D format
(.h3d file).
blank: Results are output in all active formats for which the result is available.
type
<ALL, ENERG, HOURG>
Default = ALL
ALL: All energy results are output.
ENERG: All energy results without hourglass energy are output.
HOURG: Hourglass energy only is output.
option
<YES, ALL, NO, NONE, SID, PSID>
Default = ALL
YES, ALL, blank:
Energy results are output for all elements.
NO, NONE: Energy results are not output.
SID: If a set ID is given, energy results are output only for elements listed in that set.
Argument Option Description
PSID: If a property set ID is given, energy results for the elements referencing properties listed in the property set are output.
Comments
1. ENERGY is only applicable for geometric nonlinear analysis subcases which are defined by an ANALYSIS = NLGEOM, IMPDYN or EXPDYN subcase entry. It is ignored for all other subcases.
2. Only formats that have been activated by an OUTPUT or FORMAT statement are valid for use on this card.
3. Multiple formats are allowed on the same entry; these should be comma separated. If no format is specified, then this output control applies to all formats defined by OUTPUT or FORMAT commands for which the result is available. See Results Output for information on which results are available in which formats.
4. Multiple instances of this card are allowed; if instances are conflicting, the last instance dominates.
ERP
I/O Options and Subcase Information Entry ERP - Output Request
Description
The ERP command can be used in the I/O Options or Subcase Information sections to request equivalent radiated power output for all subcases or individual subcases, respectively.
Format
ERP (format_list, grid) = option
Argument Option Description
format <H3D, PUNCH, blank>
Default = blank
H3D: Results are output in Hyper3D format (.h3d file).
PUNCH: Results are output in Nastran punch results format (.pch file).
blank: Results are output in all active formats for which the result is available.
grid <GRID>
Default = blank
GRID: Output the contribution of each grid in addition to the ERP results for the PANEL, defined by ERPPNL or PANELG (TYPE=ERP). This is a normal velocity squared for each grid specified in the panel definition.
option <YES, ALL, NO, NONE>
Default = ALL
YES, ALL, blank:
Equivalent radiated power is output for all panels.
NO, NONE: Equivalent radiated power is not output. Comments
1. Multiple formats are allowed on the same entry; these should be comma separated. If no format is specified, then this output control applies to all formats defined by OUTPUT or FORMAT commands for which the result is available. See Results Output for information on which results are available in which formats.
2. Multiple instances of this card are allowed; if instances are conflicting, the last instance dominates.
3. 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.
4. In addition to the ERP values, the following results are output to the .pch file: total ERP over the loading frequencies, fraction of the total ERP at each loading frequency, and ERP expressed in decibels ERB
dB = 10 * log10 (ERP) at eac h loading frequenc y.
5. The ERP is calculated as half the normal velocity squared of each grid multiplied by the associated area of each grid on the panel. The parameters for the speed of sound (ERPC), fluid density (ERPRHO), and radiation loss factor (ERPRLF) are used in the calculation of ERP using the formula below.
6. The calculation of ERP in decibels (dB) is performed using the PARAM data RHOCP and ERPREFDB in the equation below. ERPREFDB is the reference value in dB and RHOCP is the scale factor:
7. At least one of the bulk data entries ERPPNL or PANELG (TYPE=ERP) needs to be specified, if the ERP Output Request is used.
ESE
I/O Options and Subcase Information Entry ESE - Output Request
Description
The ESE command can be used in the I/O Options or Subcase Information sections to request strain energy and strain energy density output for all subcases or individual subcases
respectively. Format
ESE (format_list, type, dmig, peakoutput) = option
Argument Option Description
format <HM, H3D, PUNCH, OP2, PLOT, blank> Default = blank
HM: Results are output in HyperMesh
results format (.res file).
H3D: Results are output in Hyper3D format
(.h3d file).
PUNCH: Results are output in Nastran punch results format (.pch file).
OP2: Results are output in Nastran output2
format (.op2 file) (see comment 8). PLOT: Results are output in Nastran output2
format (.op2 file) when PARAM, POST is defined in the bulk data section. blank: Results are output in all active formats
for which the result is available.
type <AVERAGE, AMPLITUDE, PEAK> Default = AVERAGE See Comment 7
AVERAGE: In frequency response analysis average energy is output.
AMPLITUDE: In frequency response analysis the amplitude of energy is output. PEAK: In frequency response analysis the
peak energy is output. This is the sum of AVERAGE and AMPLITUDE.
Argument Option Description
dmig <DMIG, NODMIG> Default =
NODMIG
DMIG: Results are provided for external superelements in the .out file. NODMIG: Results are not provided for external
superelements in the .out file.
peakoutput <PEAKOUT> Default = blank
PEAKOUT: If PEAKOUT is present, only the filtered frequencies from the PEAKOUT card will be considered for this output.
option <YES, ALL, NO, NONE, SID> Default = ALL
YES, ALL, blank:
Element strain energy and strain energy density are output for all elements.
NO, NONE: Element strain energy and strain energy density are not output. SID: If a set ID is given, element strain
energy and strain energy density are output only for elements listed in that set.
Comments
1. When an ESE command is not present, element strain energy and strain energy density is not output.
2. Initial thermal strain is included in the calculation of strain energy and strain energy density.
3. Multiple formats are allowed on the same entry; these should be comma separated. If no format is specified, then this output control applies to all formats defined by OUTPUT or FORMAT commands for which the result is available. See Results Output for information on which results are available in which formats.
4. Multiple instances of this card are allowed; if instances are conflicting, the last instance dominates.
5. 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.
6. Type only applies to frequency response analysis.
7. There are three ways to calculate the Element Strain Energy in Frequency Response Analysis. They are listed as follows:
Type of Output Formula
Average Amplitude Peak Where, E = Elemental Energy {u
r } = Displac ement (Real Part)
{u
i } = Displac ement (Imaginary Part)
[Ke] = Elemental Stiffness
8. format=OUTPUT2 can also be used to request results to be output in the Nastran output2 format (.op2 file).
FLUX
I/O Options and Subcase Information Entry FLUX – Output Request
Description
The FLUX command can be used in the I/O Options or Subcase Information sections to request temperature gradient and flux output for all steady-state heat transfer analysis subcases, transient heat transfer analysis subcases or individual heat transfer analysis subcases, respectively.
Format
FLUX (format_list) = option
Argument Options Description
format <PUNCH, OP2, H3D, PLOT, blank>
Default = blank
PUNCH: Results are output in Nastran punch results format (.pch file).
OP2: Results are output in Nastran output2 format (.op2 file) (see comment 5).
PLOT: Results are output in Nastran output2 format (.op2 file) when PARAM, POST is defined in the bulk data section.
H3D: Results are output in Hyper3D format (.h3d file). blank: Results are output in all active formats for
which the result is available.
option <YES, ALL, NO, NONE, SID> Default = ALL
YES, ALL, blank:
Flux results are output for all valid elements.
NO, NONE: Flux results are not output.
SID: If a set ID is given, flux results are output only for elements referenced by that set.
Comments
1. When the FLUX command is not present, flux results are not output.
2. Flux output is only available for steady-state heat transfer analysis and transient heat transfer analysis solution sequences.
3. Multiple formats are allowed on the same entry; these should be comma separated. If no format is specified, then this output control applies to all formats defined by OUTPUT or FORMAT commands for which the result is available. See Results Output for information on the results available and their respective formats.
4. Multiple instances of this card are allowed; if instances are conflicting, the last instance dominates.
5. format=OUTPUT2 can also be used to request results to be output in the Nastran output2 format (.op2 file).