Area Command
The Area command defines a 2D area or a 1D interface which will automatically be divided into elements to define all or part of an FEA mesh.
Scripted Area Command
In scripted files, the Area command is a block that begins with Area command and ends with an EndArea command. Between the Area and its matching EndArea, the area is defined by a collection of paths that enclose the area. To define a solid 2D area, the area block must include four paths:
Area #1,#2,<#3> Paths "Bottom" Keypoint "BotLeft",0,0 Keypoints "BotRight" EndPath Paths "Right", "Top" "Left" EndArea
To define a 1D interface, the area block must includes two separate, but identical paths:
Area #1,#2,<#3> Path "Left",6 Keypoint "LeftBot",0,0 Keypoints "LeftTop" EndPath Paths "Right" EndArea
In these area blocks
- #1 is the material ID for a previously defined material. All elements in the area will be set to this material. Solid areas must use normal materials and interface areas must use interface materials. When the mesh will be defined using images and shapes, set the material ID for any region that will use the images and shapes to be _NONE_; the images and shapes will fill in the materials later.
- #2 is the thickness of all the elements in mm for 2D plane stress or plain strain analyses. It is ignored for axisymmetric analyses, but is still required.
- #3 is an optional material angle for all the elements. It may be needed for certain anisotropic materials. It can be entered as a number or as a <a href="function.html">user-defined function</a>. A function is evaluated at the midpoint of an element. Triangular elements are created in pairs and the function is evaluated at the midpoint of each pair.
The <a href="path.html">Path commands</a> within the Area
block define a series of paths that must circumnavigate the area in the counter clockwise direction. The paths must be connected and define a closed area. Each path can be explicitly defined (e.g., the paths with subordinate <a href="keypoint.html">Keypoint commands</a>) or can refer to a previously defined path (e.g., the paths with just a path name). Consecutive defined paths can be selected with multiple <a href="path.html">Path</a> commands or with a single <a href="paths.html">Paths</a> command. See the <a href="path.html">Path</a> and <a href="keypoint.html">Keypoint</a> commands for details on defining paths and keypoints.
Notes
- Currently all solid areas must be defined by four paths. Furthermore, if n1, n2, n3, and n4 are the number of intervals along the four paths, they must satisfy either n1+n2=n3+n4 or n1+n4=n2+n3.
- Interface elements must be defined by two paths. The two <a href="path.html">paths</a> must be separate paths, but must have identical properties (i.e., have the same starting and ending point, same number of intervals, and same ratio). Furthermore, the two paths must have each been previously used in exactly one solid area command.
- An FEA analysis can have any number of areas. To connect areas into a solid object, the areas must share common paths.
- The area will be meshed into elements of the type defined in the most recent <a href="element.html">Element command</a>. Solid areas must use solid elements. Interfaces must use <a href="imperfect.html">interface elements</a>.
- The Area command is only allowed for <a href="analysis.html">FEA analyses.</a>