Oasys LS-DYNA Environment 8.1 VOLUME 3 ... - Oasys Software

Oasys LS-DYNA Environment: User Guide (Version 8.1)
LS-DYNA Manual Section: *LOAD_BODY_GENERALIZED
Additional Sections: *DEFINE_CURVE
*CONTROL_DAMPING
Example of: Rotating Elements
Example Filename: shell_global.key
Description:
A body has constant angular velocity. The radial vibration introduced due to the rapid deployment
of the rotation is damped out in the initialization phase using dynamic relaxation.
Model:
The body measures 200 × 100 × 10 mm 3 . The body consists of 2 Belytschko-Tsay elastic shell
elements. The body rotates about the y-axis at 62.83 radians per second. The analysis ends at 0.1
seconds.
Input:
All nodes have an initial translational velocity based on the angular velocity v=omega x r.
(*LOAD_BODY_GENERALIZED, *DEFINE_CURVE). Dynamic relaxation damps oscillations
in the radial direction during the initialization. This essentially pre-stresses the structure and the
load continues into the analysis portion. (*LOAD_BODY_GENERALIZED)
Because of the condition of constant angular velocity of the two nodes on the axis of rotation, the
motion remains uniform throughout the calculation (*INITIAL_VELOCITY_NODE).
Reference:
Schweizerhof, K. and Weimer, K.
Page A.87