By default a volume mesh representation has no cell sets defined for it. A new cell set has to be generated before any further manipulation can be done on the set or the set contents displayed.
Three methods are available for creating a new cell set:
Each new cell set created is based on all the cells in the model, regardless of any previously generated sets. In the case of the cell list and threshold options, a dialog window will appear with the appropriate options to allow you to create the cell set, while the zone option allows you to manually select the zone of cells of interest. In all three instances however, you will be prompted as how to add the new cell set part to the current scene in order for it to be displayed.
To view the GUI options available for creating a new cell set, right-click on the Volume Mesh > Cell Sets node and select the New option:
The Empty cell set option allows you create an empty cell set node, which can be modified afterwards to include cells using any combination of the tools provided.
Once a cell set has been created, a new sequentially numbered node, starting from Cell Set 1, will be created under the Cell Sets node. Clicking on the node provides a summary of the number of cells contained in the set:
The new cell set creation tools only allow a single action to create the original cell set. If you want to apply additional criteria to further manipulate the set then you should modify the cell set using the range of global and Boolean tools available.
Cell set nodes can be renamed and deleted in the same way as other nodes.
The cell list option for creating a cell set allows individual cell ID's or offsets to be used to identify cells. Cell ID's are unique values assigned to each cell and correspond with the pro-STAR cell ID index. Cell offsets are used when the mesh has been partitioned for a parallel analysis.
In general, these options are included for developers to debug problems as the ID's and offsets won't generally be available or known to the average user.
To access the cell list options, right-click on the Cell Sets node and select New > Cell List... from the pop-up menu:
The Cell List dialog will appear.
In the dialog, select the region of interest using the Region pull-down menu and then the method used to set the Id Type, namely Cell Id or Cell Offset. The individual cell ID's or offset values can then be entered into the white box, separated by spaces.
The Display option should then be selected to determine how the new cell set part should be added to the current scene. Press the OK button to create the cell set based on the supplied information or Cancel to void the operation.
The Cell List dialog will automatically be closed once the operation is complete. If you want to apply additional criteria to further manipulate the set then you should modify the cell set using the range of global and Boolean tools available.
The threshold option allows cell sets to be created based on any of the normally available scalars such as centroid geometric range, face area magnitudes and volumes, as well as post processing items such as pressure, temperature and velocity etc, should they be available.
To access the threshold options, right-click on the Cell Sets node and select New > Threshold... from the pop-up menu:
The Threshold dialog will appear:
The Scalar field function of interest should first be selected using the pull-down menu. Press the Query button to query the range of field values in the entire cell set if desired. The Extraction Mode should then be set to determine the method used to extract the cells for the threshold. Enter the appropriate minimum/maximum or threshold value depending on the option selected.
The Display option should then be selected to determine how the new cell set part should be added to the current scene. Press the OK button to create the cell set based on the supplied information or Cancel to void the operation.
The Threshold dialog will automatically be closed once the operation is complete. If you want to apply additional criteria to further manipulate the set then you should modify the cell set using the range of global and Boolean tools available.
The zone option allows cell sets to be created based on cells contained fully within an arbitrary closed loop polygon. As such, it is a very flexible and quick method of isolating cells with just a few mouse clicks. A valid scene must be displayed in order for this option to be active.
To access the zone options, right-click on the Cell Sets node and select New > Zone... from the pop-up menu:
This will activate the mouse cross-hair selection tool, shown below:
Click on the scene to indicate the starting point of the polygon zone and then continue to click around the model to create a closed loop zone of the area of interest. An example is shown below.
To complete the zone, you can either right mouse-click or click back on the starting point of the zone. If at anytime you want to discontinue the zone then press the Escape key. Press the D key to undo the previous zone point selection.
On the successful completion of a zone, the Zone dialog will appear to indicate the display choices:
The Display option should then be selected to determine how the new cell set part should be added to the current scene. Press the OK button to create the cell set. If the appropriate display options are selected, the cell set will automatically appear within the scene:
If you want to apply additional criteria to further manipulate the set then you should modify the cell set using the range of global and Boolean tools available.
An empty cell set node, that is, one containing no cells, can be created by right-clicking on the Cell Sets node and selecting New > Empty from the pop-up menu:
The advantage of doing this is that you are initially not presented with any options for how the set should be created or displayed as part of the scene. You can then modify the cell set using the range of global and Boolean tools available.