celas

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celas

Purpose

element function for scalar springs and penalized rigid links

Description

In an model description matrix a group of celas elements starts with a header row [Inf abs('celas') 0 ...] followed by element property rows following the format [n1 n2 DofID1 DofID2 ProID EltID Kv Mv Cv Bv] with

n1,n2	node numbers of the nodes connected. Grounded springs are obtained by setting n1 or n2 to 0.
DofID	Identification of selected DOFs.
	For rigid links, the first node defines the rigid body motion. DofID (positive) defines which DOFs of the slave node are connected by the constraint. Thus [1 2 123 0 0 0 1e14] will only impose translations of node 2 are imposed by motion of node 1, while [1 2 123456 0 0 0 1e14] will also penalize the difference in rotations.
	For scalar springs, DofID1 (negative) defines which DOFs of node 1 are connected to which of node 2. DofID2 can be used to specify different DOFs on the 2 nodes. For example [1 2 -123 231 0 0 1e14] connects DOFs 1.01 to 2.02, etc.
ProID	Optional property identification number (see format below)
Kv	Optional stiffness value used as a weighting associated with the constraint. If Kv is zero (or not given), the default value in the element property declaration is used. If this is still zero, Kv is set to 1e14.

When used, element property rows for celas elements take the form (detailed under p_spring)

 [ProID type KvDefault]