Results Output by OptiStruct

The tables in this section summarize the results output for different analysis types. They show the formats available for each result and the I/O Option Entry that controls the output of the result.

The columns represent the major output streams:
H3D
Hyper3D format (.h3d file
HM
HyperMesh format (.res file)
OP2
Nastran Output2 format (.op2 file)
PCH
Nastran Punch format (.pch file)
OPT
OptiStruct ASCII format (multiple files)
PAT
Patran and Alternative-Patran formats (multiple files)
H3D (MBD)
Hyper3D format for body results (_mbd.h3d file)
MRF
Multibody results file (_mbd.mrf file)
HDF5
Hierarchical data format (.h5 file)

Linear Static Analysis and Nonlinear Static Analysis Results

  H3D HM OP2 PCH OPTI PAT HDF5 Controlling I/O Option
Nodal Displacements DISPLACEMENT
Element Strain Energy       ESE
Element Stresses4 STRESS / ELSTRESS
Element Strains 4   STRAIN
Ply Stresses   CSTRESS
Composite Failure Indices       CFAILURE
Ply Strains   CSTRAIN
Element Forces   # FORCE / ELFORCE
Failure output for elements             FAILURE
Grid Point Stresses       GPSTRESS / GSTRESS
SPC Forces     # SPCFORCE
MPC Forces     # MPCFORCE
Grid Point Forces     # GPFORCE
Applied Loads     # OLOAD
Contact Force and Pressure           CONTF
Total Force             TOTALFORCE

# Available only for Linear Static Analysis

Linear Steady-state Heat Transfer Analysis Results

  H3D OP2 PCH Controlling I/O Option
Nodal Temperatures THERMAL
Element Fluxes and Gradients FLUX
SPC Flux   SPCFORCE

Linear Transient Heat Transfer Analysis Results

  H3D OP2 PCH Controlling I/O Option
Nodal Temperatures THERMAL
Element Fluxes and Gradients   FLUX

Normal Modes Analysis Results

  H3D HM OP2 PCH OPTI PAT HDF5 Controlling I/O Option
Eigenvectors DISPLACEMENT
Element Kinetic Energy       EKE
Element Strain Energy       ESE
Grid Point Energy             GPKE
Grid Point Stress           GPSTRESS / GSTRESS
Element Stresses 4   STRESS / ELSTRESS
Element Strains 4           STRAIN
Element Forces             FORCE / ELFORCE
SPC Forces       SPCFORCE
MPC Forces       MPCFORCE
Grid Point Forces       GPFORCE
Nodal Pressures (Fluid)         PRESSURE
Ply Stresses             CSTRESS
Ply Strains             CSTRAIN

Complex Eigenvalue Analysis Results

  H3D OP2 PCH Controlling I/O Option
Eigenvectors DISPLACEMENT

Linear Buckling Analysis Results

  H3D HM OP2 PCH OPTI HDF5 Controlling I/O Option
Eigenvectors DISPLACEMENT

Aeroelastic Divergence Analysis Results

Result H3D OP2 PCH Controlling I/O Option
Eigenvectors # # DISPLACEMENT
Element Energy Loss Per Cycle # EDE
Element Kinetic Energy # EKE
Element Strain Energy # ESE

# In aeroelastic divergence analysis with multiple Mach numbers, only H3D output is available.

Aeroelastic Flutter Analysis

Result H3D OP2 PCH Controlling I/O Option
Displacements DISPLACEMENT
Modal Participation Displacements* # SDISPLACEMENT

* SDISPLACEMENT output is available only for K, PK and PKNL methods of aeroelastic flutter analysis.

# PCH output for SDISPLACEMENT is available only in sorting = SORT1.

Frequency Response Analysis Results

  H3D HM OP2 PCH OPTI HDF5 XYPUNCH Controlling I/O Option
Nodal Displacements   DISPLACEMENT
Modal Participation Displacements         SDISPLACEMENT
Element Energy Loss Per Cycle         EDE
Element Kinetic Energy         EKE
Element Strain Energy             ESE
Nodal Velocities   VELOCITY
Modal Participation Velocities         SVELOCITY
Nodal Accelerations   ACCELERATION
Modal Participation Accelerations         SACCELERATION
Element Stresses 4 STRESS / ELSTRESS
Element Strains 4 STRAIN
Modal Stresses 3         STRESS / ELSTRESS
Modal Strains 3         STRAIN
Element Forces FORCE / ELFORCE
SPC Forces       SPCFORCE
MPC Forces           MPCFORCE
Grid Point Forces       GPFORCE
Grid Point Stresses           GPSTRESS / GSTRESS
Power Flow Field             POWERFLOW
Ply Stresses             CSTRESS
Ply Strains             CSTRAIN
Sound Power              
Sound Intensity             SINTENS
Sound Pressure Level             SPL
Applied Load Vectors       OLOAD
Composite Failure Indices             CFAILURE

Coupled Frequency Response Analysis of Fluid-structural Models (Acoustic Analysis) Results

  H3D OP2 PCH HDF5 Controlling I/O Option
Nodal Displacements   DISPLACEMENT
Modal Participation Displacements   SDISPLACEMENT
Nodal Velocities   VELOCITY
Modal Participation Velocities   SVELOCITY
Nodal Accelerations   ACCELERATION
Modal Participation Accelerations   SACCELERATION
Nodal Pressures (Fluid) PRESSURE
Element Stresses 4   STRESS / ELSTRESS
Element Strains 4   STRAIN
Element Forces   FORCE / ELFORCE
SPC Forces   SPCFORCE
MPC Forces     MPCFORCE
Grid Point Forces   GPFORCE
Power Flow Field       POWERFLOW
Ply Stress       CSTRESS
Ply Strain       CSTRAIN

Transient Analysis Results

  H3D HM OP2 PCH OPTI Controlling I/O Option
Nodal Displacements   DISPLACEMENT
Modal Participation Displacements     SDISPLACEMENT
Nodal Velocities   VELOCITY
Modal Participation Velocities     SVELOCITY
Nodal Accelerations   ACCELERATION
Modal Participation Accelerations     SACCELERATION
Element Stresses 4   STRESS / ELSTRESS
Element Strains 4   STRAIN
Failure output for elements         FAILURE
SPC forces     SPCFORCE
Grid point forces   GPFORCE
Modal Stresses 3     STRESS / ELSTRESS
Modal Strains 3     STRAIN
Element Forces     FORCE / ELFORCE
MPC Forces       MPCFORCE
Ply Stresses     CSTRESS
Ply Strains     CSTRAIN
Composite Failure Indices         CFAILURE
Applied Load Vectors   OLOAD

Transient Analysis via Fourier Transformation Results

H3D HM OP2 PCH OPTI Controlling I/O Option
Nodal Displacements DISPLACEMENT
Nodal Velocities VELOCITY
Nodal Accelerations ACCELERATION
Pressure (for Infinite Element Analysis) DISPLACEMENT

Random Response Analysis Results

  OP2 PCH H3D HDF5 Controlling I/O Option
Displacement

(PSD, RMS and RMS (Cumulative))

  # DISPLACEMENT, XYPEAK / XYPLOT / XYPUNCH
Velocity

(PSD, RMS and RMS (Cumulative))

  # VELOCITY, XYPEAK / XYPLOT / XYPUNCH
Acceleration

(PSD, RMS and RMS (Cumulative))

  # ACCELERATION, XYPEAK / XYPLOT / XYPUNCH
Element Force

(PSD and RMS)

    FORCE / ELFORCE, XYPEAK / XYPLOT / XYPUNCH
Element Stress

(PSD)

  STRESS / ELSTRESS, XYPEAK / XYPLOT / XYPUNCH
Element Stress

(RMS)

1   STRESS / ELSTRESS
Element Strain

(PSD)

    STRAIN, XYPEAK / XYPLOT / XYPUNCH2
Element Strain

(RMS)

      STRAIN
SPC Force

(PSD, RMS and RMS)

  # SPCFORCE
Composite Stress

(PSD and RMS)

      CSTRESS
Composite Strain

(PSD and RMS)

      CSTRAIN
Acoustic panel participation factors     PFPANEL
Cross-power spectral density function     RCROSS

# In case of .pch format, only PSD and RMS results are available

Response Spectrum Analysis Results

  H3D HM OP2 PCH OPTI Controlling I/O Option
Nodal Displacements     DISPLACEMENT
Nodal Accelerations       ACCELERATION
Element Stresses     STRESS / ELSTRESS
Element Strains       STRAIN
Element Forces       FORCE
MPC Forces         MPCFORCE

Multibody Dynamics Analysis Results

  H3D HM OP2 H3D (MBD) MRF Controlling I/O Option
Nodal Displacements   DISPLACEMENT
Nodal Velocities     VELOCITY
Nodal Accelerations     ACCELERATION
Element Stresses 4   STRESS / ELSTRESS
Element Strains 4   STRAIN
Body time history          
System time history          
Marker time history         REQUEST
Element and Joint Forces         MBFORCE

Fatigue Analysis Results

  H3D Controlling I/O Option
Element Life LIFE
Element Damage DAMAGE

CMS Generation (Flex-Body Generation) Results

H3D OP2 MNF Controlling I/O Option
Displacements DISPLACEMENT
Element Stresses STRESS / ELSTRESS
Element Strains STRAIN
Element Forces

(CBEAM/CBAR/CROD)

FORCE / ELFORCE
Grid Point Stress (Solid elements) ✓* ✓* ✓** GPSTRESS / GSTRESS
Grid Point Strain ✓** GPSTRAIN
Multi Point Constraint Force MPCFORCE
Grid Point Forces GPFORCE

* Only output for Solid elements.

** Output for Solid and Shell elements.

CMS DMIG Residual Run (FE DMIG) Results

The following results can be recovered within the superelements in the DMIG residual run (for instance, using CBN DMIG). They should also be specified in the initial DMIG generation run and then in the subsequent residual run for them to be recovered within the superelement in the residual run. For ERP and EKE results, even if only STRESS and STRAIN are specified in the generation run, they can still be recovered in the residual run, as the ERP and ESE output are derived from STRESS and STRAIN results.
H3D OP2 PCH Controlling I/O Option
Displacements DISPLACEMENT
Element Stresses STRESS / ELSTRESS
Element Strain STRAIN
Element Forces (CBEAM/CBAR/CROD) FORCE / ELFORCE
Grid Point Stress (Solid elements) ✓* GPSTRESS / GSTRESS
Equivalent Radiated Power ERP
Element Strain Energy     ESE

* Only output for solid elements.

Explicit Dynamic Analysis Results (ANALYSIS=NLEXPL)

H3D5 HM OP2 PCH OPTI Controlling I/O Option
Nodal Displacements and Rotations DISPLACEMENT
Nodal Velocities VELOCITY
Nodal Accelerations ACCELERATION
Element Stresses STRESS / ELSTRESS
Element Strains (including Plastic strain)

For rate dependent plasticity problems, Equivalent Strain rate and Plastic Strain rate results are output. If the problem is elastic, these values are zero.

STRAIN
CBUSH Element Forces         FORCE / ELFORCE
Element Strain energy and Strain energy density         ESE

Optimization Results

  H3D HM OP2 PCH OPT PAT Controlling I/O Option
Element Density DENSITY
Element Thickness         THICKNESS
Ply Thickness         THICKNESS
% Thickness         THICKNESS
Shape         SHAPE

References

1 Only RMS Stress (total over all frequencies) are output to the PCH file. RMS Stress (cumulative up to a particular frequency) are not output to PCH file.
2 XYPLOT output request is not supported for Shell Strains.
3 The Structural Modal Stresses and Strains and Residual Vectors are output in Modal Frequency Response Analysis via the STRESS (MODAL) and STRAIN (MODAL) options. A possible use-case for Modal Strains is to setup Modal FRF/Modal Transient Analysis and use the Modal Participation Factors and Modal Strains as input for Fatigue Analysis.
4 The element stress and strain results written to the various output streams are not always the same. Refer to the following pages for more details on the stress results available in the different output streams.
5 For Explicit Dynamic Analysis H3D results are output in *_expl.h3d file.