Difference between revisions of "FEA Mesh Generation Commands"
Jump to navigation
Jump to search
| (63 intermediate revisions by the same user not shown) | |||
| Line 1: | Line 1: | ||
The best way to generate an FEA mesh is to use [[Keypoint]], [[Path]], and [[Area]] | The best way to generate an FEA mesh is to use [[Keypoint Command|Keypoint]], [[Path Command|Path]], and [[Area Command|Area]] commands. | ||
__TOC__ | |||
== Scripted Input Files == | |||
= | In scripted input files, you build the mesh by using multiple [[#mesh_cmds|mesh generation commands]]. These commands are usually grouped together, but may be at various locations in the input file. For example, a simple 2D, rectangular mesh of width <tt>#length</tt>, height <tt>#height</tt>, and thickness <tt>#thick</tt> with <tt>#horiz</tt> elements in the horizontal direction and <tt>#vert</tt> elements in the vertical direction (where terms beginning in number signs are [[Variable Names|script variables]]) can be created with: | ||
Area #matname$,#thick | |||
Path "Bottom",#horiz | |||
Keypoint "BotLeft",0,0 | |||
Keypoint "BotRight",#length,0 | |||
EndPath | |||
Path "Right",#vert | |||
Keypoints "BotRight" | |||
Keypoint "TopRight",#length,#height | |||
EndPath | |||
Path "Top",#horiz | |||
Keypoints "TopRight" | |||
Keypoint "TopLeft",0,#height | |||
EndPath | |||
Path "Left",#vert | |||
Keypoints "TopLeft","BotRight" | |||
EndPath | |||
EndArea | |||
Resequence "BotRight" | |||
<span id="mesh_cmds"></span>The following commands are used for generating the mesh in scripted files. | |||
* [[Area Command|Area]]: Define an area for mesh generation. | |||
* [[Path Command|Path]]: Define a path used in defining [[Area Command|areas]]. | |||
* [[Path Command|Paths]]: Add multiple defined paths to an [[Area Command|area]]. | |||
* [[Keypoint Command|Keypoint]]: Define a keypoint used in defining [[Path Command|paths]] | |||
* [[Keypoint Command|Keypoints]]: Add multiple defined keypoints to a [[Path Command|path]]. | |||
* [[Resequence Command]]: To turn on the option to resequence the nodes, which will minimize the bandwidth of the problem and speed the calculations. | |||
== XML Input Files == | == XML Input Files == | ||
In <tt>XML</tt> input files, | In <tt>XML</tt> input files, you build the mesh with [[#mesh_cmds_xml|mesh generation commands]] that must be within a single <tt><Mesh></tt> block. Here is a <tt><Mesh></tt> block that creates at 50X10 rectangular mesh with 6 elements in the horizontal direction and 3 in the vertical direction: | ||
<pre> | <pre> | ||
<Mesh> | <Mesh> | ||
< | <Keypoints> | ||
<pt x='0' y='0' id='lowerleft'/> | <pt x='0' y='0' id='lowerleft'/> | ||
<pt x='0' y='10' id='upperleft'/> | <pt x='0' y='10' id='upperleft'/> | ||
| Line 18: | Line 46: | ||
</Keypoints> | </Keypoints> | ||
< | <Path id="bottom" intervals='6' ratio='1'> | ||
<keypt id='lowerleft'/> | <keypt id='lowerleft'/> | ||
<keypt id='lowerright'/> | <keypt id='lowerright'/> | ||
| Line 35: | Line 63: | ||
</Path> | </Path> | ||
< | <Area mat="1" thick="10" type="4" flip="0" angle="0"> | ||
<path id="bottom"/> | <path id="bottom"/> | ||
<path id="right"/> | <path id="right"/> | ||
| Line 42: | Line 70: | ||
</Area> | </Area> | ||
</Mesh> | </Mesh> | ||
</pre> | |||
<span id="mesh_cmds_xml"></span>The fundamental <tt>XML</tt> commands for generating a mesh are: | |||
</ | |||
* [[Keypoint Command#XML Keypoints Block|<tt><Keypoints></tt>]]: Define all key point to be used in defining [[Path Command|paths]] | |||
* [[Path Command#XML Path Command|<tt><Path></tt>]]: Define a path to be used in defining [[Area Command#XML Area Block|areas]]. | |||
* [[Area Command#XML Area Block|<tt><Area></tt>]]: Define an area for mesh generation. | |||
* [[Resequence Command]]: To turn on the option to resequence the nodes, which will minimize the bandwidth of the problem and speed the calculations. | |||
== Using Images and Shapes == | |||
= | If some elements in the generated mesh are set the material id _NONE_ (see [[Area Command]]) or mat = 0 (see [[Area Command#XML Area Block|<tt><Area></tt> Command]]), you can follow mesh creation with [[Create a Mesh with Images and Shapes|image and shape commands]] to fill in material types, angles, and define the final mesh geometry. This option is described [[Create a Mesh with Images and Shapes|here]]. | ||
Latest revision as of 14:17, 2 June 2015
The best way to generate an FEA mesh is to use Keypoint, Path, and Area commands.
Scripted Input Files
In scripted input files, you build the mesh by using multiple mesh generation commands. These commands are usually grouped together, but may be at various locations in the input file. For example, a simple 2D, rectangular mesh of width #length, height #height, and thickness #thick with #horiz elements in the horizontal direction and #vert elements in the vertical direction (where terms beginning in number signs are script variables) can be created with:
Area #matname$,#thick
Path "Bottom",#horiz
Keypoint "BotLeft",0,0
Keypoint "BotRight",#length,0
EndPath
Path "Right",#vert
Keypoints "BotRight"
Keypoint "TopRight",#length,#height
EndPath
Path "Top",#horiz
Keypoints "TopRight"
Keypoint "TopLeft",0,#height
EndPath
Path "Left",#vert
Keypoints "TopLeft","BotRight"
EndPath
EndArea
Resequence "BotRight"
The following commands are used for generating the mesh in scripted files.
- Area: Define an area for mesh generation.
- Path: Define a path used in defining areas.
- Paths: Add multiple defined paths to an area.
- Keypoint: Define a keypoint used in defining paths
- Keypoints: Add multiple defined keypoints to a path.
- Resequence Command: To turn on the option to resequence the nodes, which will minimize the bandwidth of the problem and speed the calculations.
XML Input Files
In XML input files, you build the mesh with mesh generation commands that must be within a single <Mesh> block. Here is a <Mesh> block that creates at 50X10 rectangular mesh with 6 elements in the horizontal direction and 3 in the vertical direction:
<Mesh>
<Keypoints>
<pt x='0' y='0' id='lowerleft'/>
<pt x='0' y='10' id='upperleft'/>
<pt x='50' y='0' id='lowerright'/>
<pt x='50' y='10' id='upperright'/>
</Keypoints>
<Path id="bottom" intervals='6' ratio='1'>
<keypt id='lowerleft'/>
<keypt id='lowerright'/>
</Path>
<Path id="right" intervals='3'>
<keypt id='lowerright'/>
<keypt id='upperright'/>
</Path>
<Path id="top" intervals='6'>
<keypt id='upperright'/>
<keypt id='upperleft'/>
</Path>
<Path id="left" intervals='3'>
<keypt id='upperleft'/>
<keypt id='lowerleft'/>
</Path>
<Area mat="1" thick="10" type="4" flip="0" angle="0">
<path id="bottom"/>
<path id="right"/>
<path id="top"/>
<path id="left"/>
</Area>
</Mesh>
The fundamental XML commands for generating a mesh are:
- <Keypoints>: Define all key point to be used in defining paths
- <Path>: Define a path to be used in defining areas.
- <Area>: Define an area for mesh generation.
- Resequence Command: To turn on the option to resequence the nodes, which will minimize the bandwidth of the problem and speed the calculations.
Using Images and Shapes
If some elements in the generated mesh are set the material id _NONE_ (see Area Command) or mat = 0 (see <Area> Command), you can follow mesh creation with image and shape commands to fill in material types, angles, and define the final mesh geometry. This option is described here.