Database Considerations
To support the many activities it performs, Creo Simulate adds information to existing Creo Parametric files and creates database files in the directory that stores your Creo Parametric part or assembly.
To learn about Creo Simulate database files, how the software maintains the database, and other related issues, read the following:
In reading this material, bear in mind that you do not need an in-depth understanding of the Creo Simulate database in order to work with your model. Treat these discussions as background information only.
Native Mode Files
For native mode, the software creates many files as it proceeds through the menus and commands. Some of these files store part or assembly information, including simulation information, others store mesh and results information, while still others store a record of the session.
The following files contain most of your model data and results data:
• Model files—Creo Simulate stores simulation information in Creo Parametric .prt files (part mode) and .asm files (assembly mode).
• Model with mesh files—When you run an analysis or design study, Creo Simulate creates a study directory and copies the .prt or .asm file to that directory. In the course of the run, the software generates a separate model file that includes geometry, simulation entities, and the mesh generated during the run. This type of model file is called .mdb (part mode) or .mda (assembly mode).
The most important thing to bear in mind is that these files are paired —.prt files with .mdb files and .asm files with .mda files.
Following is a brief summary of the purpose of each file:
• .prt file—This file stores information about part geometry and all simulation entities for the part.
• .mdb file—The content of this file depends on whether or not you have actually run an analysis or design study. When you begin a run or create a mecbatch file, the .mdb file contains a subset of simulation entities such as measures, materials, analysis definitions, and so forth. Once the analysis or design study begins to run, Creo Simulate updates this file to include the model mesh.
• .asm file—This file stores information about assembly geometry and all simulation entities for the assembly.
• .mda files—As with the .mdb file, the content of these files depends on whether or not you have actually run an analysis or design study. When you begin a run or create a mecbatch file, the .mda file contains a subset of simulation modeling entities for your assembly. Once the analysis or design study begins to run, Creo Simulate updates this file to include model mesh.
To help prevent data loss and enable you to return to a prior model if you encounter problems, the software creates .prt or .asm backups each time you perform a save through the Creo Parametric File menu. The backup files are as follows:
• .prt and .asm files—an earlier version of the file. For the most recent backup, use the file with the next-to-highest number, although you can also access an earlier version of the part or assembly by opening files with lower numbers.
• Session files—Each session of Creo Parametric or Creo Simulate generates one session record, or playback file in case you need to replay a session. Creo Parametric and Creo Simulate use a trail.txt.n (where n is an integer) file to store session records. The software starts a new trail.txt.n file at the beginning of each session, incrementing the integer to create a unique identity.
To learn more about the file structure and some of the guidelines you should observe as you work with these files, read the following:
Overview of File Creation
To give you an understanding of when Creo Simulate creates files, the following discussion guides you through the Creo Simulate process from a file creation perspective, as started from part mode.
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File creation is similar for assembly mode, so simply substitute appropriate file extensions to see how file creation takes place in assembly mode.
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1. When you open Creo Parametric, the software creates a trail file, trail.txt.n, which tracks your actions in Creo Parametric. The software stores this file in the current directory.
2. When you create and save a part, Creo Parametric saves the geometry, relations, and so forth in a part (.prt) file, which it stores in the pro directory (where pro is the directory that contains the Creo Parametric part).
3. After you enter Creo Simulate, the software stores Creo Simulate entities that you add to the part—modeling entities, analysis definitions, and design study definitions—in the .prt file. After meshing your model with AutoGEM, if you decide to save your mesh, the mesh is saved in a separate mesh file (.mmp for parts and .mma for assemblies).
4. When you run an analysis or design study, Creo Simulate creates a study directory (where study is the name of your design study). The software then copies the .prt file into this directory, creates an .mdb file, and merges the simulation information from the .prt file into the .mdb file.
The .mdb file that appears in the study directory has the same name as the study. However, the .prt file that appears in the study directory has the same name as the original name of the part.
As Creo Simulate runs the analysis or design study, it updates the .mdb file by adding mesh data. Creo Simulate uses this information to display model results.
Starting a New Model
If you need to start a fresh simulation model for the part or assembly, you can click > > . This command deletes the simulation information in the .prt or .asm file, eliminating most modeling entities for the part or assembly.
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Do not use the New Simulation Model command if you are trying to delete individual modeling entities. Reserve this command for situations where your model requires deep-level cleanup.
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File Commands
Following is a list of actions Creo Simulate takes when you use the model management commands on the File menu.
File menu option
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Action taken by Creo Simulate
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Save Options
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>
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Saves the Creo Simulate model.
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> >
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Saves the Creo Simulate model with a new name.
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> >
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If you have accessed Creo Simulate at least once during the current Creo Parametric session, saves a backup of the Creo Simulate model in a directory with a name you specify.
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Manage File Options
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> >
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Renames the current object with a new name. You can rename the object for just the current session or permanently on disk.
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> >
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Deletes all except the latest version of the object from the hard disk. Prompts you to enter the name of the object whose old versions are to be deleted.
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> >
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Deletes all versions of the current object from the hard disk.
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Manage Session Options
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> >
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Erases the current object in the display window from memory without saving the changes. For an assembly Creo Simulate prompts you to select the sub components you want to erase.
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> >
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Erases objects that are not currently displayed in the active window.
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> >
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Plays a specified trail file of a session. You can use trail files to view the record of activity so that you can reconstruct a previous working session or recover from an abrupt termination of a session. Refer to the Fundamentals Help for more information on using trail files.
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> >
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Opens the Server Manager dialog box and allows you to register and set up a Windchill server. For more details on working with a connected server and the associated file commands, refer to the Data Management Help.
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> >
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Selects the working directory. Your working directory is an area you designate to store Creo Simulate files.
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> >
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Displays all objects in the memory in an information window. This list includes all parts, drawings and assemblies on disk as well.
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For more information on the file commands refer to the Fundamentals Help.
FEM Database Considerations
As you perform the three phases of finite element modeling (preprocessing, processing, and postprocessing), a number of different files are added to the Creo Parametric database. This section lists and describes these files.
To learn more about FEM files, read the following:
By default, all files you create by using Creo Simulate FEM mode have the format "modelname.ext," where modelname is the name of the current model and ".ext" is a three-character extension indicating the file type.
Files Output to FEA Programs
Following is a list of files that are output by Creo Simulate FEM mode meshing for export to an offline finite element analysis program or by FEM mode postprocessing directly to an online finite element analysis program.
• modelname.ans—ANSYS output file
• modelname.nas—MSC/NASTRAN output file
• modelname.fnf—FEM Neutral output file
Miscellaneous FEM Mode Database Files
Following is a list of various files that are generated in FEM mode during the finite element modeling process.
File
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Description
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modelname.bde
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File listing problem mesh elements that fail a requested quality check
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modelname.fmp
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File containing mesh data of a part
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modelname.fma
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File containing mesh data of an assembly
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modelname.frd
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File containing model mesh and results data
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modelname.inf
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File listing a definition of your model and finite element results statistics
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modelname.plt
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Plot file output from postprocessing
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Support for Pro/INTRALINK and PTC Windchill
Integrated mode
Creo Simulate supports direct access of certain files to an active Pro/INTRALINK workspace and to
PTC Windchill. These include
Creo Simulate part and assembly
model files, and files associated with meshing in
integrated and
FEM mode.
Creo Simulate also supports direct access for analysis results files in native integrated mode and fnf files for external pressure loads, external temperature loads and external convection coefficient loads. Other files that you generate in
Creo Simulate, and which are discussed elsewhere in this document and in
Files Created by Creo Simulate, including study directories, and property library files, are not supported for Pro/INTRALINK or
Windchill access.
To learn more about file support, read the following:
Model Files
• When you enter Creo Simulate, model files, .prt and .asm, are read from the active workspace.
• If your active workspace does not contain a Creo Simulate model, but there is a model on disk in the current working directory, it will be read from disk and checked into the workspace.
In either case, when you save your model, Creo Simulate writes it to the active workspace. The software also automatically creates a Pro/INTRALINK dependency between a Creo Simulate model and its associated Creo Parametric model when it saves the model to your active workspace.
Creo Simulate reads certain auxiliary files from the workspace, such as those containing temperature fields for structural analysis. These files are not written to the workspace, so you must either check these files out of common space or import them into a workspace before Creo Simulate can access them directly.
Meshing Files
If you are working in Pro/INTRALINK, the following points apply to your AutoGEM .mmp and .mma files in Creo Simulate.
• Associating files
—There is no dependency established between a part or assembly file and a mesh file when you import them from a directory into your workspace. To establish an association:
1. Import both files into your workspace.
2. Open the .prt or .asm file in your workspace.
3. Click > to open the AutoGEM dialog box.
4. Select > on the AutoGEM dialog box to open the mesh file (.mmp or .mma).
5. Select > on the AutoGEM dialog box to save the mesh file in your workspace.
6. Check the part or assembly files and the mesh files into the commonspace.
• Saving files—If you have checked out a part or assembly from commonspace into a workspace, when you select the > command on the AutoGEM dialog box to save a new mesh file, the .mmp or .mma file is saved into the same workspace.
If you retrieved the mesh file from commonspace, when you select the > command on the AutoGEM dialog box, the software checks the mesh file out and then saves it to the same workspace.
• Retrieving files—Here are the rules that Creo Simulate uses to determine which mesh file to retrieve when you open a mesh file and a part file in your Pro/INTRALINK workspace.
◦ If you check out both the mesh file and the model file from common space into your workspace at the same time, and then open Creo Simulate, the software tries to check out the latest version of the mesh file that is compatible with the model file. If it cannot find an appropriate version of the mesh file, it uses the version of the mesh file that is specified by the user configuration.
◦ If you check out a model file from common space into your workspace without simultaneously checking out a mesh file, open Creo Simulate, and then use the AutoGEM dialog box to retrieve a mesh file, the software will try to find a compatible mesh file. If no appropriate file is available, Creo Simulate displays an error message.
◦ If you check out a mesh file from common space into your workspace without checking out a model file, the software automatically checks out an associated model file.
FEM Mode Meshing Files
If you are working in Pro/INTRALINK, the same rules apply to saving and retrieving your FEM mode .fmp and .fma files as discussed above for .mmp and .mma files.
If you work with hierarchical meshes, when you check out an assembly from a workspace, the software checks out both the meshes saved for the parts and the meshes saved for the assembly.
Meshing Files Support for PTC Windchill
If you are working in Windchill, the following points apply to your AutoGEM .mmp and .mma files in Creo Simulate.
• When you create a mesh file, it is added to the same Windchill document as the Creo Simulate model file.
• When you retrieve a part or assembly file from a Windchill cabinet, the latest version of the .mmp or .mma file corresponding to the model file is also retrieved.
• If you update a .mmp or .mma file, the version number of the Windchill document is incremented.
The behavior when you retrieve or save .fma and .fmp files is identical to that for the .mmp and .mma files.
Analysis Results Files in Pro/INTRALINK and PTC Windchill
You can compress and save the results directory to the active workspace when working online in either Pro/INTRALINK or Windchill
• The results directory is compressed and saved to the workspace with the file extension mrs.
• The mrs compressed file references the last checked in model using a derived link.
• When you retrieve a part it does not result in simultaneous download of the results file.
FNF Files in Pro/INTRALINK and PTC Windchill
When working online in either Pro/INTRALINK or Windchill you can save FNF files associated with a model to the workspace. FNF files are saved in the active workspace as secondary content of the model with the file extension .fnf.
• When searching for an FNF file, if in online mode and if the .fnf file already exists in the workspace, that version will take precedence over the .fnf file in the original location.
• If you preview the distribution, Creo Simulate read the .fnf file from the workspace and not from the location shown in the load dialog box.
Refer to the Data Management Help for more information on workspaces, registering servers and working online and offline.