CORIOLIS
CORIOLIS, Option,
--, --,
RefFrame, RotDamp, RotMass
Applies the Coriolis effect to a rotating structure.
OptionFlag to activate or deactivate the Coriolis effect:
1 (ON or YES)
—
Activate. This value is the default.
0 (OFF or NO)
—
Deactivate.
--,--Unused fields.
RefFrameFlag to activate or deactivate a stationary reference frame.
1 (ON or YES)
—
Activate.
0 (OFF or NO)
—
Deactivate. This value is the default.
RotDampFlag to activate or deactivate rotating damping effect.
1 (ON or YES)
—
Activate.
0 (OFF or NO)
—
Deactivate. This value is the default.
RotMassFlag to activate or deactivate rotor mass summary printout (only supported for
RefFrame= ON).1 (ON or YES)
—
Activate.
0 (OFF or NO)
—
Deactivate. This value is the default.
Notes
The CORIOLIS command is used for linear analyses in either a rotating or a stationary reference frame, and
performs differently according to the designated RefFrame value.
The CORIOLIS command must be specified
during the first step of the analysis. The rotational velocity must be defined using
OMEGA (when the whole model is rotating) or
CMOMEGA (component based rotation). Specific
restrictions and elements apply to each case, as follows:
- Rotating Reference
Frame (
RefFrame= OFF) The command applies the Coriolis effect in the following structural element types: MASS21, SHELL181, PLANE182, PLANE183, SOLID185, SOLID186, SOLID187, BEAM188, BEAM189, SOLSH190, SHELL281, PIPE288 and PIPE289. It also applies this effect in the following coupled-field elements when structural degrees of freedom are present: PLANE222, PLANE223, SOLID225, SOLID226, and SOLID227.
The rotating damping effect (
RotDamp= ON) is only supported by the COMBI214 element when stationary.In a rotating reference frame, the Coriolis and spin-softening effects, as well as the centrifugal forces, contribute to the dynamics and are applied by default.
- Stationary Reference Frame
(
RefFrame= ON) The command activates the gyroscopic damping matrix in the following structural elements: MASS21, BEAM188, SHELL181, BEAM189, SOLID185, SOLID186, SOLID187, SOLSH190, SOLID272, SOLID273, SHELL281, PIPE288, PIPE289, and MATRIX50.
The rotating structure is assumed to be axisymmetric about the axis of rotation.
The rotating damping effect (
RotDamp= ON) is supported by the elements listed above that generate a gyroscopic damping matrix. It is also supported by some specific elements (see Adding Damping in the Rotordynamic Analysis Guide for a complete list).The rotor mass summary printout (
RotMass= ON) is only supported for some of the elements that generate a gyroscopic damping matrix: MASS21, BEAM188, BEAM189, PIPE288, and PIPE289. The EMAT file is required (EMATWRITE,YES).
To include Coriolis effects in a linear perturbation (prestressed) analysis, follow the procedure detailed in Considerations for Rotating Structures.
In a nonlinear transient analysis in which the model is actually spinning (ANTYPE,TRANS and NLGEOM,ON) the CORIOLIS command must not be used as any spinning motion applied through either the IC or D commands automatically includes nonlinear inertia terms such as the Coriolis effect.
To take into account variable bearings (COMBI214 elements with tabular user-defined characteristics), you must activate the Coriolis effect in a stationary reference frame. The gyroscopic effect coming from COMBI214 mass characteristics is not supported.
For more information about using the CORIOLIS command, see Rotating Structure Analysis in the Advanced Analysis Guide and also Overview of the Rotordynamic Analysis Process in the Rotordynamic Analysis Guide. For details about the Coriolis and gyroscopic effect element formulations, see the Mechanical APDL Theory Reference.
Elements with layered section properties do not support Coriolis effects (rotating and stationary reference frames).
This command is also valid in PREP7.