Element Types - Revision history

Nairnj: /* MPM Element Types */

2013-11-15T18:48:14Z

MPM Element Types

← Older revision		Revision as of 18:48, 15 November 2013
Line 48:		Line 48:
	== MPM Element Types ==		== MPM Element Types ==

	In theory, MPM could use any element type ~~int he~~ background. In practice, all MPM codes use linear elements and unpublished attempts to try other element types have not been successful. Furthemore, many MPM features required a regular orthogonal grid, although there is no particular need for grid spacings to be the same in all directions. As a result, MPM in 2D and 3D uses the following two types of elements		In theory, MPM could use any element type in the background. In practice, all MPM codes use linear elements and unpublished attempts to try other element types have not been successful. Furthemore, many MPM features required a regular orthogonal grid, although there is no particular need for grid spacings to be the same in all directions. As a result, MPM in 2D and 3D uses the following two types of elements

	* <tt>2</tt> or "4 Node Quadrilateral": 4-node rectangular (usually) elements (linear)		* <tt>2</tt> or "4 Node Quadrilateral": 4-node rectangular (usually) elements (linear) for 2D MPM
	* <tt>7</tt> or "8 Node Brick": 8-node rectangular box (usually) elements (linear)		* <tt>7</tt> or "8 Node Brick": 8-node rectangular box (usually) elements (linear) for 3M MPM

	These MPM element types, in there usual shape, are illustrated in the following figure.		These MPM element types, in there usual shape, are illustrated in the following figure.

Nairnj: /* Notes */

2013-11-15T18:47:16Z

Notes

← Older revision		Revision as of 18:47, 15 November 2013
Line 59:		Line 59:
	== Notes ==		== Notes ==

	# When different element types are using in a single analysis (including mixing of [[#Solid Elements\|solid elements]] and [[#Interface Elements\|interface elements]], they must all be compatible elements. In other words, you can mix linear elements (types 1, 2, and 5) with each other or quadratic elements (types 3, 4, 6, and 8) with each other, but cannot mix linear elements with quadratic elements in the same mesh.		# When different element types are using in a single analysis (including mixing of [[#Solid Elements\|solid elements]] and [[#Interface Elements\|interface elements]]), they must all be compatible elements. In other words, you can mix linear elements (types 1, 2, and 5) with each other or quadratic elements (types 3, 4, 6, and 8) with each other, but cannot mix linear elements with quadratic elements in the same mesh.

Nairnj: /* Notes */

2013-11-15T18:46:59Z

Notes

← Older revision		Revision as of 18:46, 15 November 2013
Line 59:		Line 59:
	== Notes ==		== Notes ==

	# When ~~mixed~~ elements ~~are used~~, they must be compatible elements. In other words, you can mix linear elements (types 1, 2, and 5) with each other or quadratic elements (types 3, 4, 6, and 8) with each other, but cannot mix linear elements with quadratic elements in the same mesh.		# When different element types are using in a single analysis (including mixing of [[#Solid Elements\|solid elements]] and [[#Interface Elements\|interface elements]], they must all be compatible elements. In other words, you can mix linear elements (types 1, 2, and 5) with each other or quadratic elements (types 3, 4, 6, and 8) with each other, but cannot mix linear elements with quadratic elements in the same mesh.

Nairnj: /* XML Input Files */

2013-11-15T18:45:15Z

XML Input Files

← Older revision		Revision as of 18:45, 15 November 2013
Line 44:		Line 44:
	== XML Input Files ==		== XML Input Files ==

	In <tt>XML</tt> input files, the first [[Area Command#XML Area Block\|<tt><Area></tt> block]] must define an element <tt>type</tt> in an attribute and refer to it by number from the [[#FEA Element Types\|above list]]. Subsequent <tt><Area></tt> blocks can omit the <tt>type</tt> attribute unless the element type is changed to have an analysis with mixed elements. Solid (or quadrilateral) [[Area Command\|areas]] can only use [[#Solid Elements\|solid elements]] while interface [[Area Command\|areas]] can use only [[#Interface Elements\|interface elements]]. For triangular elements, the diagonals are flipped using a <tt>flip</tt> attribute on the [[Area Command#XML Area Block\|<tt><Area></tt>]] command instead of using a separate [[#Scripted Input Files\|<tt>FlipTriangles</tt> command]].		In <tt>XML</tt> input files, the first [[Area Command#XML Area Block\|<tt><Area></tt> block]] must define an element <tt>type</tt> in an attribute and refer to it by number from the [[#FEA Element Types\|above list]]. Subsequent <tt><Area></tt> blocks can omit the <tt>type</tt> attribute unless the element type is changed to have an analysis with mixed elements. Solid (or quadrilateral) [[Area Command#XML Area Block\|areas]] can only use [[#Solid Elements\|solid elements]] while interface [[Area Command#XML Area Block\|areas]] can use only [[#Interface Elements\|interface elements]]. For triangular elements, the diagonals are flipped using a <tt>flip</tt> attribute on the [[Area Command#XML Area Block\|<tt><Area></tt>]] command instead of using a separate [[#Scripted Input Files\|<tt>FlipTriangles</tt> command]].

	== MPM Element Types ==		== MPM Element Types ==

Nairnj: /* XML Input Files */

2013-11-15T18:44:42Z

XML Input Files

← Older revision		Revision as of 18:44, 15 November 2013
Line 44:		Line 44:
	== XML Input Files ==		== XML Input Files ==

	In <tt>XML</tt> input files, the first [[Area Command#XML Area Block\|<tt><Area></tt> block]] must define an element <tt>type</tt> in an attribute and refer to it by number from the [[#FEA Element Types\|above list]]. Subsequent <tt><Area></tt> blocks can omit the <tt>type</tt> attribute unless the element type is changed to have an analysis with mixed elements. Solid (or quadrilateral) [[Area Command\|areas]] can only use [[#Solid Elements\|solid elements]] while interface [[Area Command\|areas]] can use only [[#Interface Elements\|interface elements]]. For triangular elements, the diagonals are flipped using a <tt>flip</tt> attribute on the [[Area Command#XML Area Block\|<tt><Area></tt>]] command instead of using a separate <tt>FlipTriangles</tt> command.		In <tt>XML</tt> input files, the first [[Area Command#XML Area Block\|<tt><Area></tt> block]] must define an element <tt>type</tt> in an attribute and refer to it by number from the [[#FEA Element Types\|above list]]. Subsequent <tt><Area></tt> blocks can omit the <tt>type</tt> attribute unless the element type is changed to have an analysis with mixed elements. Solid (or quadrilateral) [[Area Command\|areas]] can only use [[#Solid Elements\|solid elements]] while interface [[Area Command\|areas]] can use only [[#Interface Elements\|interface elements]]. For triangular elements, the diagonals are flipped using a <tt>flip</tt> attribute on the [[Area Command#XML Area Block\|<tt><Area></tt>]] command instead of using a separate [[#Scripted Input Files\|<tt>FlipTriangles</tt> command]].

	== MPM Element Types ==		== MPM Element Types ==

Nairnj: /* XML Input Files */

2013-11-15T18:44:07Z

XML Input Files

← Older revision		Revision as of 18:44, 15 November 2013
Line 44:		Line 44:
	== XML Input Files ==		== XML Input Files ==

	In <tt>XML</tt> input files, the first [[Area Command#XML Area Block\|<tt><Area></tt> block]] must define an element <tt>type</tt> in an attribute and refer to it by number from the [[#FEA Element Types\|above list]]. Subsequent <tt><Area></tt> blocks can omit the <tt>type</tt> attribute unless the element type is changed to have an analysis with mixed elements. For triangular elements, the diagonals are flipped using a <tt>flip</tt> attribute on the [[Area Command#XML Area Block\|<tt><Area></tt>]] command instead of using a separate <tt>FlipTriangles</tt> command.		In <tt>XML</tt> input files, the first [[Area Command#XML Area Block\|<tt><Area></tt> block]] must define an element <tt>type</tt> in an attribute and refer to it by number from the [[#FEA Element Types\|above list]]. Subsequent <tt><Area></tt> blocks can omit the <tt>type</tt> attribute unless the element type is changed to have an analysis with mixed elements. Solid (or quadrilateral) [[Area Command\|areas]] can only use [[#Solid Elements\|solid elements]] while interface [[Area Command\|areas]] can use only [[#Interface Elements\|interface elements]]. For triangular elements, the diagonals are flipped using a <tt>flip</tt> attribute on the [[Area Command#XML Area Block\|<tt><Area></tt>]] command instead of using a separate <tt>FlipTriangles</tt> command.

	== MPM Element Types ==		== MPM Element Types ==

Nairnj: /* Scripted Input Files */

2013-11-15T18:42:59Z

Scripted Input Files

← Older revision		Revision as of 18:42, 15 November 2013
Line 34:		Line 34:
	Element (elem)		Element (elem)

	where <tt>(elem)</tt> is a number or name from the [[#FEA Element Types\|above lists]]. Once an element is selected, it remains the element used for all subsequent [[Area Command\|Area commands]]. If no <tt>Element</tt> command has been used, FEA calculations will default to "8 Node Quadrilateral" elements. Solid (or quadrilateral) [[Area Command\|areas]] can only use [[#Solid Elements\|solid elements]] while interface [[Area Command\|areas]] can use only [[#Interface Elements\|interface elements]].		where <tt>(elem)</tt> is a number or name from the [[#FEA Element Types\|above lists]] (by name or number). Once an element is selected, it remains the element used for all subsequent [[Area Command\|Area commands]]. If no <tt>Element</tt> command has been used, FEA calculations will default to "8 Node Quadrilateral" elements. Solid (or quadrilateral) [[Area Command\|areas]] can only use [[#Solid Elements\|solid elements]] while interface [[Area Command\|areas]] can use only [[#Interface Elements\|interface elements]].

	When using triangular elements (type 1 and 4), quadrilateral areas meshed using the [[Area Command]] first meshes the area into quadrilaterals and then creates triangular elements by dividing each quadrilaterals along its diagonal. To determine which diagonal in used, you can use the <tt>FlipTriangles</tt> command: into triangular elements. The command to flip triangles is		When using triangular elements (type 1 and 4), quadrilateral areas meshed using the [[Area Command]] first meshes the area into quadrilaterals and then creates triangular elements by dividing each quadrilaterals along its diagonal. To determine which diagonal in used, you can use the <tt>FlipTriangles</tt> command: into triangular elements. The command to flip triangles is

Nairnj: /* Scripted Input Files */

2013-11-15T18:42:47Z

Scripted Input Files

← Older revision		Revision as of 18:42, 15 November 2013
Line 34:		Line 34:
	Element (elem)		Element (elem)

	where <tt>(elem)</tt> is a number or name from the [[#FEA Element Types\|above ~~list~~]]. Once an element is selected, it remains the element used for all subsequent [[Area Command\|Area commands]]. If no <tt>Element</tt> command has been used, FEA calculations will default to "8 Node Quadrilateral" elements. Solid (or quadrilateral) [[Area Command\|areas]] can only use [[#Solid Elements\|solid elements]] while interface [[Area Command\|areas]] can use only [[#Interface Elements\|interface elements]].		where <tt>(elem)</tt> is a number or name from the [[#FEA Element Types\|above lists]]. Once an element is selected, it remains the element used for all subsequent [[Area Command\|Area commands]]. If no <tt>Element</tt> command has been used, FEA calculations will default to "8 Node Quadrilateral" elements. Solid (or quadrilateral) [[Area Command\|areas]] can only use [[#Solid Elements\|solid elements]] while interface [[Area Command\|areas]] can use only [[#Interface Elements\|interface elements]].

	When using triangular elements (type 1 and 4), quadrilateral areas meshed using the [[Area Command]] first meshes the area into quadrilaterals and then creates triangular elements by dividing each quadrilaterals along its diagonal. To determine which diagonal in used, you can use the <tt>FlipTriangles</tt> command: into triangular elements. The command to flip triangles is		When using triangular elements (type 1 and 4), quadrilateral areas meshed using the [[Area Command]] first meshes the area into quadrilaterals and then creates triangular elements by dividing each quadrilaterals along its diagonal. To determine which diagonal in used, you can use the <tt>FlipTriangles</tt> command: into triangular elements. The command to flip triangles is

Nairnj: /* Scripted Input Files */

2013-11-15T18:42:17Z

Scripted Input Files

← Older revision		Revision as of 18:42, 15 November 2013
Line 34:		Line 34:
	Element (elem)		Element (elem)

	where <tt>(elem)</tt> is a number or name from the [[#FEA Element Types\|above list]]. Once an element is selected, it remains the element used for all subsequent [[Area Command\|Area commands]]. If no <tt>Element</tt> command has be used, FEA calculations will default to "8 Node Quadrilateral" elements.		where <tt>(elem)</tt> is a number or name from the [[#FEA Element Types\|above list]]. Once an element is selected, it remains the element used for all subsequent [[Area Command\|Area commands]]. If no <tt>Element</tt> command has been used, FEA calculations will default to "8 Node Quadrilateral" elements. Solid (or quadrilateral) [[Area Command\|areas]] can only use [[#Solid Elements\|solid elements]] while interface [[Area Command\|areas]] can use only [[#Interface Elements\|interface elements]].

	When using triangular elements (type 1 and 4), quadrilateral areas meshed using the [[Area Command]] first meshes the area into quadrilaterals and then creates triangular elements by dividing each quadrilaterals along its diagonal. To determine which diagonal in used, you can use the <tt>FlipTriangles</tt> command: into triangular elements. The command to flip triangles is		When using triangular elements (type 1 and 4), quadrilateral areas meshed using the [[Area Command]] first meshes the area into quadrilaterals and then creates triangular elements by dividing each quadrilaterals along its diagonal. To determine which diagonal in used, you can use the <tt>FlipTriangles</tt> command: into triangular elements. The command to flip triangles is
Line 41:		Line 41:

	where <tt>(option)</tt> is <tt>yes</tt> or <tt>no</tt> to flip or not flip the triangles. This argument is optional. If it is omitted, the command will toggle the previous setting for triangle flipping. The initial value is always <tt>no</tt>. Any new setting by a <tt>FlipTriangles</tt> command remains in effect until it is changed by another <tt>FlipTriangles</tt> command.		where <tt>(option)</tt> is <tt>yes</tt> or <tt>no</tt> to flip or not flip the triangles. This argument is optional. If it is omitted, the command will toggle the previous setting for triangle flipping. The initial value is always <tt>no</tt>. Any new setting by a <tt>FlipTriangles</tt> command remains in effect until it is changed by another <tt>FlipTriangles</tt> command.

	Solid (or quadrilateral) [[Area Command\|areas]] can only use [[#Solid Elements\|solid elements]] (types 1, 2, 3, 4, and 8) while interface areas can use only [[#Interface Elements\|interface elements]] (type 5 and 6).

	== XML Input Files ==		== XML Input Files ==

Nairnj: /* Scripted Input Files */

2013-11-15T18:41:04Z

Scripted Input Files

← Older revision		Revision as of 18:41, 15 November 2013
Line 40:		Line 40:
	FlipTriangles <(option)>		FlipTriangles <(option)>

	where <tt>(option)</tt> is <tt>yes</tt> or <tt>no</tt> to flip or not flip the triangles. This argument is optional. If it is omitted, the command will toggle the previous setting for triangle flipping. The initial value is always <tt>no</tt>.		where <tt>(option)</tt> is <tt>yes</tt> or <tt>no</tt> to flip or not flip the triangles. This argument is optional. If it is omitted, the command will toggle the previous setting for triangle flipping. The initial value is always <tt>no</tt>. Any new setting by a <tt>FlipTriangles</tt> command remains in effect until it is changed by another <tt>FlipTriangles</tt> command.

	~~This command takes effect when~~ [[Area Command\|areas]] ~~defined by four paths are meshed into trangular~~ elements~~. Triangular~~ elements ~~are created by meshing the area in to quadrilaterals~~ and then dividing each quadrilaterals along its diagonal. The flip triangles option determines which diagonal is used. Any new setting by a <tt>FlipTriangles</tt> command remains in effect until it is changed by another <tt>FlipTriangles</tt> command.		Solid (or quadrilateral) [[Area Command\|areas]] can only use [[#Solid Elements\|solid elements]] (types 1, 2, 3, 4, and 8) while interface areas can use only [[#Interface Elements\|interface elements]] (type 5 and 6).

	== XML Input Files ==		== XML Input Files ==