RBAR

Bulk Data Entry

RBAR – Rigid Bar

Description

Defines a rigid bar with six degrees-of-freedom at each end.

Format

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
RBAR	EID	GA	GB	CNA	CNB	CMA	CMB	ALPHA

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
RBAR	5	1	2	234	123			1.45e-5

Field	Contents
EID	Unique element identification number. Must be unique.
GA,GB	Grid point identification number of connection points. (Integer > 0 or <PartName.number>) See comment 5.
CNA,CNB	Independent degrees-of-freedom in the global coordinate system for the element at grid points GA and GB. Up to six unique digits (0 < digit < 6) may be placed in each field with no embedded blanks, or the field may be left blank. See comment 1.
CMA,CMB	Component numbers of dependent degrees-of-freedom in the global coordinate system assigned by the element at grid points GA and GB. Up to six unique digits (0 < digit < 6) may be placed in each field with no embedded blanks, or the field may be left blank. See comment 2.
ALPHA	Thermal Expansion Coefficient (see comment 6). (Real > 0.0 or blank)

Comments

1.	The total number of components in CNA and CNB must equal six, for example, CNA = 1236, CNB = 34. Furthermore, they must jointly be capable of representing any general rigid body motion of the element.

2.	If both CMA and CMB are zero or blank, all of the degrees-of-freedom not in CNA and CNB are made dependent.

3.	The degree of freedom declared dependent on this entry may not be:

•	Included in a single point constraint (SPC or SPC1)

•	Declared a dependent degree-of-freedom on any other RBAR, RBE1, RBE2, RBE3, or RROD entry

•	Declared a dependent degree-of-freedom on an MPC set referenced by a subcase

4.	Rigid elements are ignored in heat transfer analysis.

Supported local entries in specific parts can be referenced by the use of “fully qualified references” on RBAR entries in the model. A fully qualified reference (“PartName.number”) is similar to the format of a numeric reference. “PartName” is the name of the part that contains the referenced local entry (part names are defined on the BEGIN Bulk Data Entry in the model). “number” is the identification number of a referenced local entry in the part “PartName”. See Parts and Instances in the User’s Guide for detailed information on the use of fully qualified references.

The thermal expansion effect will be computed, if you supply the thermal expansion coefficient ALPHA, and the thermal load is requested by the TEMPERATURE(INITIAL) and TEMPERATURE(LOAD) subcase information entries. The temperature of the element is taken to be the average of the temperatures at all the nodes of the element.

7.	This card is represented as a weld element in HyperMesh.