SYNCHRO

SYNCHRO, RATIO, Cname
Specifies whether the excitation frequency is synchronous or asynchronous with the rotational velocity of a structure.

MP ME ST <> <> <> EM <> PP EME MFS

RATIO

The ratio between the frequency of excitation and the frequency of the rotational velocity of the structure. This value must be greater than 0. The default is an unbalance excitation (RATIO = 1.0).

Cname

The name of the rotating component on which to apply the harmonic excitation.

Notes

The SYNCHRO command specifies whether the excitation frequency is synchronous or asynchronous with the rotational velocity of a structure in a harmonic analysis. Use the command to take into account rotating harmonic forces on rotating structures.

Mechanical APDL calculatestes the rotational velocity Ω of the structure from the excitation frequency f, defined (via the HARFRQ command) as Ω = 2πf / RATIO. The rotational velocity is applied along the direction cosines of the rotation axis (specified via an OMEGA or CMOMEGA command).

Specifying any value for RATIO causes a general rotational force excitation and not an unbalance force. To define an unbalance excitation force (F = Ω2 * Unb), RATIO should be left blank (the nodal unbalance Unb is specified via the F command).

The SYNCHRO command is valid only for a full-solution harmonic analysis (HROPT,Method = FULL) and the Variational Technology method (HROPT,Method = VT) involving a rotating structure (OMEGA or CMOMEGA) with Coriolis enabled in a stationary reference frame (CORIOLIS,,,,RefFrame = ON).

Menu Paths

Main Menu>Preprocessor>Loads>Define Loads>Apply>Structural>Inertia>Angular Veloc>Synchronous
Main Menu>Solution>Define Loads>Apply>Structural>Inertia>Angular Veloc>Synchronous

Release 16.2 - © SAS IP, Inc. All rights reserved.