CMROTATE
CMROTATE, CM_Name
, ROTATX
, ROTATY
, ROTATZ
, X1
, Y1
, Z1
, X2
, Y2
, Z2
Specifies the rotational velocity of an element component in a brake-squeal
analysis.
CM_Name
The name of the element component.
ROTATX
,ROTATY
,ROTATZ
If the
X2
,Y2
,Z2
fields are not defined,ROTATX
,ROTATY
, andROTATZ
specify the components of the rotational angle vector in the global Cartesian X, Y, Z directions.If the
X2
,Y2
,Z2
fields are defined, onlyROTATX
is required.ROTATX
specifies the scalar rotational velocity about the rotational axis. The rotational direction ofROTATX
is designated either positive or negative, and is determined by the "right hand rule."X1
,Y1
,Z1
If the
X2
,Y2
,Z2
fields are defined,X1
,Y1
, andZ1
define the coordinates of the beginning point of the rotational axis vector. Otherwise,X1
,Y1
, andZ1
are the coordinates of a point through which the rotational axis passes.X2
,Y2
,Z2
The coordinates of the end point of the rotational axis vector.
Notes
The CMROTATE command specifies the rotational
motion velocity components ROTATX
, ROTATY
, and ROTATZ
of an
element component CM_Name
about a user-defined
rotational axis. The rotational axis can be defined either as a vector
passing through a single point or a vector connecting two points. CMROTATE can be used in static analyses (ANTYPE,STATIC) and modal analyses (ANTYPE,MODAL).
This command sets the constant rotational velocity on the nodes of the specified element component, despite any deformation at the nodes. This feature is primarily used for generating sliding contact at frictional contact interfaces in a brake-squeal analysis. This type of analysis typically involves surface-to-surface contact between the brake pad and the rotating disk. The applicable contact elements, therefore, are CONTA174 and CONTA175.
A brake-squeal analysis generally involves a linear perturbation modal analysis subsequent to a large-deformation static analysis with the Newton-Raphson option set as NROPT,UNSYM. Therefore, CMROTATE is not applicable for multiple load step solves using the LSSOLVE command.
The load interpolation setting (KBC) applies to the
rotational velocity, in particular the OMGSQRDKEY
option for quadratic
interpolation.
This command is also valid in PREP7.