THIS 22.1

Ansys LS-DYNA

Ansys LS-DYNA

This topic includes:


Users are strongly advised to run each Ansys LS-DYNA analysis in a separate directory. Some of the default names for the files generated by Ansys LS-DYNA that T/HIS can read are not unique and T/HIS can not tell which files belong to which model. If you do read multiple models from the same directory T/HIS will generate a warning message if you read the same file for more than 1 model.

Selecting Models

There are three ways to select the Ansys LS-DYNA models that you want to read into T/HIS

(i) Select a single model (see Select Model )
(ii) Search directories for results and open open multiple models (see Search Directories Recursively )
(iii) Open a model database and select the models you want to read ( see Select Models From Database )

Select Model

Select ANY results file from a model. T/HIS will then search for all the results files in that directory produced by the same analysis as the selected file (as illustrated below) and display a list of all the files found. The user can then select which files to open. The default is to open all the available results files.

If you are using Oasys Ltd SHELL to submit jobs then the default filenames will be "jobname.thf", "jobname.xtf", "binout", "abstat" etc. If you use the standard Ansys LS-DYNA output file names then the filenames will be "d3thdt", "xtfile", "binout", "abstat".

The T/HIS preference option "this*file_names" can be used to set the default filenames that T/HIS searches for to either the ARUP set or the LST names.

When the user selects Apply , the selected files are then opened and the contents scanned. After the files have been scanned the list of available data types will automatically be displayed ( see Data Components )

Search Directories Recursively

Multiple models can be opened by using the option to search directories recursively.

After a directory has been specified T/HIS will display a list of all the models it can find in the directory structure and each file can be selected. The order in which the models are read in can be specified by selecting the models in the order required. The selection buttons will display the model number that each model will be read into. The model numbering begins from the next free model number and is then sequential.

Select Models From Database

From T/HIS 10.0 onwards users can select models from a model database. The database file is an XML format file that contains information on where models are located along with a brief description of each model, (see below for more details on the file format).

To select a model database either enter it's name in the text box or use the file selector.

The default model database can be specified as a command line argument (see Command Line Options for more details). The default database filename and location can also be specified in the preference file (see Format of the oa_pref File for more details)

this*database_dir:
this*database_file:

After a database file has been selected it's contents will be read and T/HIS will display a Tree Like menu showing the contents of the database.

As each item is displayed T/HIS will check to see if the files that it refers to exist.

If a file does exist then a green tick will be displayed
If a file does not exist then a red cross will be displayed

The number of levels in the database that are automatically expanded when it is first displayed can be specified in the preference file (see Format of the oa_pref File for more details)

this*database_expand:

After selecting the required models use Apply to close the database window and return to the main menu where the selected models will be displayed along with the model numbers they will be read in as.
Selecting Models

Models can be selected and deselected by clicking on each row. Multiple models can be selected by clicking on the 1st model and holding down SHIFT while selecting the last model in the range.

As each model is selected, the model number that it will be read in as is automatically displayed alongside the model description.

A complete branch can be selected/deselected by selecting the branch label (Iteration 1).

Modifying the Database

Database entries can be added, removed and modified by right clicking on a branch label or a model description

Right clicking on a branch label will display 4 options

Modify ... Modify the branch label.

Add Model ...
Add a new model into the selected branch. A menu will be displayed to select a new model and to define the model description that is displayed for the new model.
Insert ... Insert a new branch within the selected branch.
Delete Delete this branch and everything within it.

Right clicking on a model description will display 3 options

Modify ... Modify the model location and description.
Insert ... Insert a new branch. The selected model will be moved into the new branch.
Delete Delete the model

Saving the Database

After modifying the database use the Save option to save the changes for future sessions.
Creating a new Database

If you do not have a database or if you want to create a new one then T/HIS can create the new database for you. To create a new database click the CREATE button and simply enter the name of the new database file in the text box that appears, T/HIS will then check that the file does not already exist and if it doesn't it will create a new empty database.

Alternatively if you type in the name of a file in the main Open Plot File window that does not exist then T/HIS will ask if you want to create a new empty database using that filename.

Once you have done this you can use the Modify options above to add items into the database and then save the file before exiting.

Database Format

The Model Database uses an ASCII XML file format.

All items with the database are either branches or models. Each database entry has an XML name and a LABEL element. Models also contain a model element that contains the full pathname of one of the files belonging to the model.

The XML name should be unique and should obey the following rules

  • Names can contain letters, numbers, and other characters
  • Names must not start with a number or punctuation character
  • Names must not start with the letters xml (or XML, or Xml, etc)
  • Names cannot contain space

    • The LABEL is the string used to display an item within the tree view. Unlike the XML name the LABEL can contain any ASCII character.

    <model_database version="10.000000">
        <Template_Demo label="Template Demo">
            <iteration_1 label="Iteration 1">
                <base label="Base"
                    model="e:\release\meeting\crush\base\base.ptf"/>
                <run_1 label="Run 1"
                    model="e:\release\meeting\crush\run1\run1.ptf"/>
                <run_2 label="Run 2"
                    model="e:\release\meeting\crush\run2\run2.ptf"/>
                <run_3 label ="Run 3"
                    model="e:\release\meeting\crush\run3\run3.ptf"/>
                <run_4 label="Run 4"
                model="e:\release\meeting\crush\run4\run4.ptf"/>
            </iteration_1>
            <iteration_2 label="Iteration 2">
                <base label="Base"
              
              model="e:\test\crush2\base\base.ptf"/>
                <run_1 label="Run 1"
              
              model="e:\test\crush2\run1\run1.ptf"/>
                <run_2 label="Run 2"
              
              model="e:\test\crush2\run2\run2.ptf"/>
                <run_3 label="Run 3"

              model="e:\test\crush2\run3\run3.ptf"/>
                <run_4 label="Run 4"
              
              model="e:\test\crush2\run4\run4.ptf"/>
                </iteration_2>
            </Template_Demo>
    </model_database>

    Automatic extraction of model results

    When a second or subsequent model is opened in T/HIS this option can be used to automatically generate the same curves as those already read from another model.

    This option can also be used if a model is re-read into T/HIS to extract the same curves as those that had already been read from the model.

    By default this option will attempt to generate curves that match those already read from model 1. If results have already been read from more than one model then the model to match the curves form can be set to any of the existing models.

    This option can be used to overwrite the existing curves from a model. If a model has been read into T/HIS and curves have been read from the model while the analysis was still running then this option can be used to automatically update the curves.


    When the curves from the 2nd or subsequent model are automatically generated then by default they will be given the same colours, and line styles as the curves in the original model.

    Instead of copying the curve styles a new style for all the automatically generated curves can be specified. This make it very easy to set the same style for all of the curves that are read from a model. Alternatively the default T/HIS curve styles can be used.


    Model Unit System

    This option can be used to set the default Unit System that will be applied to the model. For more information on Units see UNITS

    Entity Types

    Items are shown in bright green if they occur in all the models that have been read into T/HIS and are currently selected. If they occur in at least one model but not all models then they are shown in a duller green (in the case shown in the adjacent picture Beams, Shells, Stonewalls, Springs, Seatbelts, Retractors, Sliprings and SPCs can be found in some but not all of the models).


    Data Components

    When reading data from any of the Ansys LS-DYNA binary files or the Ansys LS-DYNA ASCII files multiple components and entities may be selected at the same time.

    Each data extraction menu consists of a list of available data components and a list of entities.

    Data Components

    Individual data components can be selected using the mouse. If a component has been selected and a second item is subsequently selected the first item will be deselected.

    Multiple components may be selected by

    1. Holding down the CTRL key when selecting items to add individual items to the list of selected components.

    2. Holding down the SHIFT key when selecting items to add a range of items to the list of selected components.

    3. Clicking on the first item to be selected and then dragging down the list of items without letting go of the mouse button.

    Entities

    Individual entities can be selected/deselected using the mouse.

    Multiple entities may be selected by

    1. Holding down the CTRL key when selecting items to add them to the list of selected entities.
    2. Holding down the SHIFT key when selecting items to add a range of items to the list of selected entities.
    3. Clicking on the first item to be selected and then dragging down the list of items without letting go of the mouse button.

    Entities can be sorted in four ways:

    Sort by model

    		will list all entities in the lowest number model in order of ascending ID number, then all entities in the next-lowest model, and then move through the rest of the models in ascending order.
    Sort by ID
    		will list all entities in ascending order showing the model ID for each entity
    Common IDs
    		will list only the entities with IDs that are common to all models without showing the model ID's
    Sort by Name
    		arranges the entities in alphabetical order based on their names.

    Surfaces/Integration Points

    Some BEAM, SHELL, and THICKSHELL data components can be read from multiple integration points.

    If a data component is available for multiple integration points then an additional Select Surface options is displayed.

    Select Surface

    This option will display a separate menu listing all of the integration points that are available to read data from.

    For Shell and Thick Shell elements the menu will include all of the through thickness integration points plus 3 additional options; TOP, MIDDLE and BOTTOM.

    For Beam elements the menu will just display the integration points.


    In plane int points

    In addition to the through thickness integration points recent versions of Ansys LS-DYNA can also output data for multiple in-plane integration points for fully integrated Shell and Thick Shell elements. If T/HIS can identify that the model contains data for multiple in-plane integration points then these options can be used to select the individual in-plane integration points or to average the 4 in-plane points.

    For more information on selecting integration points for beams, shells and thick shells see Beam Data Components , Shell Data Components and Thick Shell Data Components.

    Shell and ThickShell Data Components

    If Shell and ThickShell data is being read from the LDSA (binout) file then the file can contain data components in both the ELOUT and ELOUTDET branches.

    By default T/HIS uses the data from ELOUTDET as ELOUT only contains a subset of the data in ELOUDET.

    In some versions of Ansys LS-DYNA it is possible to change the Shell and ThickShell data components written to the ELOUT so that they are defined using the global coordinate system (see EOCS on *CONTROL_OUTPUT) instead of the default element local coordinate system. If this option is used then only the ELOUT file is modified, the ELOUDET file is still written using the local coordinate system.


    Use ELOUT instead of ELOUTDET

    If T/HIS detects that the LSDA file contains both ELOUT and ELOUDET and that they are using different coordinate systems then this option can be used to force T/HIS to use the ELOUT file data components using the global coordinate system.

    This option can also be set via the preference file (see Appendix H for more details) and via the command line (see Command Line Options )

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