GAMBIT MODELING GUIDE: 3. MESHING THE MODEL, 3.5

The following commands are available on the Mesh/Group subpad.

Symbol	Command	Description
	Mesh Groups	Creates a mesh for all components of a group
	Summarize Group Meshes Check Group Meshes	Summarizes general group mesh information; summarizes group mesh quality information
	Delete Group Meshes	Deletes the mesh from groups

The following sections describe the purpose and operation of each of the commands listed above.

3.5.1 Mesh Groups

The Mesh Groups command activates meshing operations for one or more groups of topological entities.

Overview

When you mesh a group by means of the Mesh Groups command, GAMBIT performs meshing operations for all of the topological entities that comprise components of the group. If you apply meshing parameters to any or all components of the group prior to executing the Mesh Groups command, GAMBIT meshes those components according to their previously applied parameters. All other components of the group are meshed according to the default meshing parameters. For example, if you mesh a group that includes three edges to one of which has been previously applied a double-sided, successive-ratio grading scheme, GAMBIT honors the applied scheme when it meshes the group but meshes the other two edges according to the current default grading scheme.

Group Meshing Parameters

To perform a group meshing operation, you must specify the following parameters:

Group name(s)
Mesh node spacing

The group name(s) parameter specifies the name of one or more existing groups the components of which are to be meshed. The mesh node spacing parameter specifies the number of edge mesh intervals that are to be created on all edges for which a grading scheme has not been previously applied.

For a description of the mesh node spacing specifications, see "Specifying Node Spacing," in Section 3.2.1.

Using the Mesh Groups Form

To open the Mesh Groups form (see below), click the Mesh command button on the Mesh/Group subpad.

The Mesh Groups form includes the following specifications.

Groups	specifies the group(s) to be meshed.
Spacing	-------------------------
Apply	specifies that the current mesh node spacing parameter is applied to all components of the group.
Default	resets the mesh node spacing parameter to its default values.
`Value`	specifies the numerical component of the mesh node spacing parameter.
Interval size Interval count Shortest edge (%)	specifies the unit definition of the mesh node spacing parameter.
Options	-------------------------
Mesh	specifies that a new mesh is created for the specified group(s).
Remove old mesh	specifies the deletion of any current mesh that is associated with the specified group(s) and created by means of the Mesh Groups form.
Remove lower mesh	specifies that all lower-topology (volume, face, and edge) meshes associated with the specified group(s) are deleted.

3.5.2 Summarize Group Meshes / Check Group Meshes

The Summarize Group Meshes / Check Group Meshes command buttons let you perform the following operations.

Symbol	Command	Description
	Summarize Group Mesh	Summarizes general group mesh information in the Transcript window
	Check Group Meshes	Displays mesh quality information in the Transcript window

The following sections describe the procedures and specifications required to execute the operations listed above.

Summarize Group Meshes

The Summarize Group Meshes command displays in the Transcript window mesh summary information for all topological entities that comprise the components of a group.

Using the Summarize Group Meshes Form

To open the Summarize Group Meshes form (see below), click the Summarize command button on the Mesh/Group subpad.

The Summarize Group Meshes form contains the following specification.

Groups

specifies the group for which summary information is displayed in the Transcript window.

Check Group Meshes

The Check Group Meshes command displays mesh quality data for entities associated with sepcified groups. When you execute the Check Group Meshes command, GAMBIT displays the following elements in the Transcript window:

Tables that summarizes 2-D and 3-D mesh quality statistical information for all faces and volumes associated with the specified group(s)
Summary statements that include the number of inverted 2-D or 3-D elements as well as the numbers of specified faces and volumes in the specified group(s) that contain inverted mesh elements.

Tabular Mesh Quality Data

The Check Group Meshes tabular output represents the statistical distributions of element mesh quality values for the current default 2-D and 3-D quality metrics. For descriptions of the information contained in such outputs, as well as the procedures for specifying the quality metrics, see Sections 3.3.8 and 3.4.6 in this guide.

Summary Statement

The Check Group Meshes summary statement indicate the numbers of faces and/or volumes in the specified group(s) that "fail" the mesh check. In the context of the Check Group Meshes command, any face or volume that includes at least one inverted mesh element fails the mesh check.

Using the Check Group Meshes Form

To open the Check Group Meshes form (see below), click the Check command button on the Mesh/Group subpad.

The Check Group Meshes form contains the following specification.

Groups specifies the groups for which mesh element quality is to be evaluated.

3.5.3 Delete Group Meshes

The Delete Group Meshes command removes the mesh from all topological entities that comprise components of one or more groups.

Using the Delete Group Meshes Form

To open the Delete Group Meshes form (see below), click the Delete command button on the Mesh/Group subpad.

The Delete Group Meshes form includes the following specifications.

Groups	specifies the group(s) for which the mesh is to be deleted.
All Pick	All specifies all groups in the model. Pick specifies groups selected by means of the Groups list box. (NOTE: If you pick a group in the graphics window or click in the Groups list box, GAMBIT automatically selects the Pick option.)
Groups	specifies the groups containing topological entities from which the mesh is to be removed.