abextract

AnalysisOptions.abextract(mode1='', mode2='', **kwargs)

Extracts the alpha-beta damping multipliers for Rayleigh damping.

Mechanical APDL Command: ABEXTRACT

Parameters:

mode1str

First mode number.

mode2str

Second mode number.

Notes

abextract calls the command macro dmpext to extract the damping ratio of MODE1 and MODE2 and then computes the Alpha and Beta damping multipliers for use in a subsequent structural harmonic or transient analysis. See Damping in the Structural Analysis Guide for more information on the alpha and beta damping multipliers. The damping multipliers are stored in parameters ALPHADMP and BETADMP and can be applied using the alphad and betad commands. Before calling abextract, you must issue rmflvec to extract the modal displacements. In addition, a node component FLUN must exist from all FLUID136 nodes. See for more information on thin film analyses.

This command is also valid in PREP7. Distributed-Memory Parallel (DMP) Restriction This command is not supported in a DMP solution.