| Tool |
Tool Name |
Description
|
| File:Tool SelectVertices.GIF |
Select Nodes |
The Select Nodes tool is used to select a set of nodes for some subsequent operation such as deletion. The coordinates of a selected node can be edited by dragging the node while this tool is active. The coordinates of selected nodes can also be edited using the Edit Window. A node can also be selected by using the Find Node command in the Mesh menu. The user is prompted for a node ID and the node is selected. Any previously selected nodes are unselected.
|
| File:Tool SelectTriangles.GIF |
Select Elements |
The Select Elements tool is used to select a set of elements for operations such as deletion or assigning a material type. An element can also be selected by using the Find Element command in the Mesh menu. The user is prompted for an element ID and the element is selected. Any previously selected elements are unselected.
|
| File:Tool SelectVertexString.GIF |
Select Node Strings |
The Select Node Strings tool is used to select one or more strings of nodes. Node strings are used for operations such as adding breaklines to the mesh.
The procedure for selecting node strings is somewhat different than the normal selection procedure. Strings are selected as follows:
- Click on the starting node for the string. The node selected will be highlighted in red.
- Click on any subsequent nodes you would like to add to the string (nodes do not have to be adjacent). The selected nodes are now connected by a solid red line.
To remove the last node from a string, press the Backspace key. To abort entering a node string, press the ESC key. To end a node string, press Return or double-click on the last node in the string. Another node string can then be selected.
|
| File:Tool CreateVertices.GIF |
Create Nodes |
The Create Nodes tool is used to manually add nodes to a mesh. When this tool is selected, clicking on a point within the Graphics Window will place a node at that point. What happens to the node after it is added (whether and how it is triangulated into the mesh) depends on the settings in the Node Options dialog in the Modify Mesh menu.
|
| File:Tool CreateLinTriElement.GIF |
Create Linear Triangle Element |
Four types of elements are supported by the 2D Mesh module:
- File:Tool CreateLinTriElement.GIF Three node triangles (linear triangles).
- File:Tool CreateQuadLinElement.GIF Six node triangles (quadratic triangles).
- File:Tool CreateLinQuadElement.GIF Four node quadrilaterals (linear quadrilaterals).
- File:Tool CreateQuadQuadElement.GIF Eight node quadrilaterals (quadratic quadrilaterals).
Elements can be created using automatic meshing techniques such as triangulation. However, it is often necessary to edit a mesh by creating elements one at a time using the four Create Element tools.
See the "Creating an Element" section below.
|
| File:Tool CreateQuadLinElement.GIF |
Create Quadratic Triangle Element
|
| File:Tool CreateLinQuadElement.GIF |
Create Linear Quadrilateral Element
|
| File:Tool CreateQuadQuadElement.GIF |
Create Quadratic Quadrilateral Element
|
| File:Tool MergeSplit.GIF |
Merge/Split |
If the Merge/Split tool is selected, clicking on a triangle edge with the mouse cursor will cause the two triangular elements adjacent to the edge to be merged into a quadrilateral element provided that the quadrilateral shape formed by the two triangles is not concave.
The Merge/Split tool can also be used to undo a merge or to "unmerge" a quadrilateral element. A quadrilateral element can be split into two triangles by clicking anywhere in the interior of the element. This tool is useful if a pair of triangles are inadvertently merged.
|
| File:Tool SwapEdges.GIF |
Swap Edges |
If the Swap Edges tool is selected, clicking on the common edge of two adjacent triangles will cause the edge to be swapped as long as the quadrilateral shape formed by the two triangles is not concave.
Occasionally, it is useful to interactively or manually swap the edges of two adjacent triangles. This can be thought of as a quick and simple alternative to adding breaklines to ensure that the edges of the triangular elements honor a geometrical feature that needs to be preserved in the mesh.
|
| File:Tool ContourLabels.GIF |
Contour Labels |
The Contour Label tool is used to manually place numerical contour elevation labels at points clicked on with the mouse. These labels remain on the screen until the contour options are changed, until they are deleted using the Contour Labels dialog, or until the mesh is edited in any way. Contour labels can be deleted with this tool by holding down the Shift key while clicking on the labels. This tool may only be used when the 2D mesh is in plan view.
|
