Background – Which Files!

SolidWorks Simulation (SWS) results are stored in a proprietary *.CWR format. SWS creates intermediate files during the analysis and combines them in the CWR file at end of run. SWS uses the standard Microsoft IStorage interface to create the CWR file, so it is possible to open the CWR file with the stg file examiner (formerly available from Microsoft Support).

SWS_FileFormat_Image1

The above files contain all the data required to show all of the results plots from a FEA run.

It is not necessary to extract the files from the CWR container file. Setting the save intermediate files in SWS prevents the above files and more from being erased after a run. The above list shows which files from the many available are important!

Set the above option flag under Simulation/Options.../Default Options/Results/Results Folder.

Set the above option flag under Simulation/Options…/Default Options/Results/Results Folder.

Most of the files are in proprietary binary format; a few are text providing SWS run time messages. The order of execution can provide useful information on the file contents. FEA programs solve for displacement before stresses, so file time stamps can hint at what will be in a file. A large FEA run provided the following approximate run sequence:

ELF -> LCD -> EFF -> OUT -> STE -> GEN -> MAS

All dimensions and stresses are stored in metric: m and N/m^2

ELF File Format – Element Flexibility? – File #1

The ELF format contains node ordered data. This file type has been examined for models with 3, 4, 6 and 10 nodes per element. The file contains data for 6 degrees of freedom for each node, whether the degrees of freedom are required or not. Plate models use 6 degrees of freedom per node, solid and axisymmetric 3 degrees per node. The data start point changes with the number of nodes per element. Data is in single precision.

See the macro “ExamineELF” in the attached spreadsheet ELF File Examiner to examine data in 3,4,6 and 10 node per element models. Other node counts have not been tested. These macros use an array write command that cannot process huge files – make sure all of your data is imported before using.

LCD File Format – Displacement – File #2

The LCD file contains node ordered data. This file type has been examined for models with 3, 4, 6 and 10 nodes per element. The data always starts at 370h. The nodes always have 6 degrees of freedom, required or not.

See the macro “ExamineLCD” in the attached spreadsheet LCD File Examiner to examine data in 3,4,6 and 10 node per element models. Other node counts have not been tested.

This data exactly matches the results from the Displacement listing.

EFF File Format – Unknown – File #3

The purpose of the EFF file has not been determined.

See the macro “ExamineEFF” in the attached spreadsheet EFF File Examiner to examine data in 3,4,6 and 10 node per element models. Other node counts have not been tested.

OUT File Format – Solver Messages – File #4

The OUT text file contains a plain English language report.

STE File Format – Stress and Strain – File # 5

The number of nodes per element, and if the model is a shell or solid is required prior to reading the STE file. The STE file contains stress and strain data per node per element. The stress for a node is the AVEARAGE of the stress for that node in all elements that it occurs in.

As an example, we use this data for our linearization program. For each node on the linearization line, we average the stress for that node as reported by all elements that connect to it. All other nodes are ignored.

See the macro “ExamineSTEFile” in the attached spreadsheet STE File Examiner The spreadsheet has been tested for 3 and 6 node per element plate models and 4 and 10 node solid models. Other node counts have not been tested. Enter the nodes per element and “plate” or “solid” options in the spreadsheet before importing the file. This macro does not contain array fast write methods, so large files will take a while to examine. The results will not match your stress plots until all nodal occurrences are averaged.

To examine Axis-Symmetric models, set the correct number of nodes per element (3 or 6), but set the plate/solid option to SOLID.

GEN File Format – Original Node Coordinates – File # 6

The GEN binary file contains nodal coordinates prior to displacement in meters. Number of Elements is stored at 18Ch and the number of nodes at 190h. Data starts at 408h. Each record of singles is X, Y, Z and followed by 10 unwanted singles.

See the macro “ExamineGENFile” in the attached spreadsheet GEN File Examiner. No difference in file format has been noticed for 3, 4 or 10 node per element files.

MAS File Format – Unknown – File # 7

Data blocks are long – contents are unknown.

General Comments

We developed this access method because we had difficulty getting raw data out of SWS. SWS provides a series of API function calls to access the data in open files. We tried that method and it took hours to get data out of a large file. SWS also has a series of export data commands in the drop down menus. They also are slow – it would take up to 10 hours to export the data from a large FEA run. We successfully used this file format information in VBA to extend our stress linearization spreadsheet to directly access the CWR file results. We can get at the data we need quickly and easily.

[File: PVE-4631 / PVE-9259, Last Updated: Aug. 24, 2015, By:LRB]