Ruled Domain#

Description#

Meshes are generated from “domains” which consist of a closed set of edges, and an arbitrary number of closed internal boundaries. For placing a mapped mesh in a domain, a mapped (or ruled) domain must be created. Mapped meshes impose specific restrictions on the domain, such as requiring a singly connected closed boundary (no holes) and considerations for node spacing along the edges.

Domains are selected in a counter-clockwise sense in order to make a closed domain. Either 3 or 4 sides may be selected. In the case of 3 sides, the last side is collapsed and triangles are created about that corner. Domains with 3 sides must have the same number of nodes on the 1st and 3rd side, while 4 sided domains must have the same number of nodes on sides 1 and 3, and the same number on 2 and 4 (but quite possibly different from the first set).

Complex domains can be created using the Group edges command. Composite edges can be used in domains as long as the edge node numbering (total of composite edge) meets the requirements for the mapped mesh.

Dialog Options#

The ruled domain popup dialog has some parameters which need selecting:

  • Elset name: The name of an elset which will be applied to all the elements created for the domain (change using cmd-M when the domain is selected (yellow)).

  • s3d, c2d, cax, etc: element geometry to use. Note axisymmetric has its own “space.” All types can be extended to 3D, but if the domain is outside the \(z=0\) plane, s3d should be selected.

  • Linear - Quadratic: Element interpolation.

  • Normal - Reduced: Element integration order.

  • Averaging - Sides 2&4 linear: Method of mapping. When using the method of sides 2&4 linear, make sure that the selected sides number 2 and 4 are linear to obtain the desired meshed domain (see figure below).

../../_images/RuledDomain.svg

Example#

The following is an example of ruled meshing, with the click sequences labeled.

../../_images/mapped.fig.svg