.op2 file
The .op2 file is a Nastran output2 format for model and results data.
File Creation
This file is created when the O2, OUT2, or OUTPUT2 formats are chosen. (See documentation for the I/O Option OUTPUT).
File Contents
Result |
Description |
Acceleration |
Acceleration results from frequency response, acoustic, transient response, and multi-body dynamics analyses. Output is controlled by the I/O Option ACCELERATION. |
Composite ply strain |
Ply strain results for composite materials from static analyses. Output is controlled by the I/O Option CSTRAIN and by the SOUTi field on the PCOMP definition. |
Composite ply stress |
Ply stress results for composite materials from static analyses. Output is controlled by the I/O Option CSTRESS and by the SOUTi field on the PCOMP definition. |
Composite failure indices |
Failure indices for composite materials from static analyses. Output is controlled by the I/O Option CSTRESS, by the SOUTi, SB and FT fields on the PCOMP definition, and by the related fields on the relevant material definition (see MAT1, MAT2, MAT8). |
Density |
Density results from topology optimizations. Output is controlled by the I/O Option DENSITY. Note: Density results are reported as element strain energy. |
Displacement |
Displacement results from static, frequency response, acoustic, transient response, and multi-body dynamics analyses. Output is controlled by the I/O Option DISPLACEMENT. |
Eigenvector |
Eigenvector results from normal modes and linear buckling analyses. Output is controlled by the I/O Option DISPLACEMENT. |
Element energy |
Element energy loss per cycle and energy loss per cycle density output from frequency response analysis. Output is controlled by the I/O Option EDE. |
Element force |
Element force results from static, frequency response, acoustic, and transient response analyses. Output is controlled by the I/O Option FORCE (or ELFORCE). |
Element kinetic energy |
Element kinetic energy and kinetic energy density output from frequency response analysis. Output is controlled by the I/O Option EKE. |
Element strain energy |
Element strain energy and strain energy density results from static, normal modes, frequency response, and transient response analyses. Output is controlled by the I/O Option ESE. |
Grid point stress |
Grid point stress results for 3D elements from static analyses. Output is controlled by the I/O Option GPSTRESS (or GSTRESS). |
MPC force |
Multi-point force of constraint results from static, frequency response, acoustic, and transient response analyses. Output is controlled by the I/O Option MPCFORCE. |
PSD element strain |
Power spectral density function of element strains from random response analysis. Output is controlled by the I/O Option STRAIN. |
PSD element stress |
Power spectral density function of element stresses from random response analysis. Output is controlled by the I/O Option STRESS. |
RMS element strain |
Root mean square value of element strains from random response analysis. Output is controlled by the I/O Option STRAIN. |
RMS element stress |
Root mean square value of element stresses from random response analysis. Output is controlled by the I/O Option STRESS. |
SPC force |
Single-point force of constraint results from static, frequency response, acoustic, and transient response analyses. Output is controlled by the I/O Option SPCFORCE. |
Strain |
Strain results from static, frequency response, acoustic, transient response, and multi-body dynamics analyses. Output is controlled by the I/O Option STRAIN. |
Stress |
Stress results from static, frequency response, acoustic, transient response, and multi-body dynamics analyses. Output is controlled by the I/O Option STRESS (or ELSTRESS). |
Velocity |
Velocity results from frequency response, acoustic, transient response, and multi-body dynamics analyses. Output is controlled by the I/O Option VELOCITY. |
1. | The I/O Option RESULTS controls the frequency of output for analytical results during an optimization. |
2. | In addition to the analysis and optimization results, the finite element model description (nodes, elements, coordinates systems, and properties) is written to the .op2 file. This model can be read by HyperView and fatigue codes. To turn off the model output, use the NOMODEL option on OUTPUT, OP2. |
3. | To be able to read the model directly from the .op2 file, newer versions of FEMFAT, Medina (7.4.8 or newer), and Animator (3.0.6.6c or newer) must be used. |
4. | For dynamic analyses like frequency response, transient response, and multi-body dynamics, it is recommended that sets be used to reduce the amount of model and results output data. The output file can become very large since results are output for each frequency or time step. |