RBAR

Bulk Data Entry 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

Example

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

Definitions

Field Contents SI Unit Example
EID Unique element identification number. Must be unique.
GA,GB Grid point identification number of connection points.

(Integer > 0 or <PartName.number>) 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. 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. 2
ALPHA Thermal expansion coefficient. 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.
  5. 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 Guide for detailed information on the use of fully-qualified references.
  6. 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.