Mechanical APDL Structural Analysis Guide

You can specify more than one form of damping in a model. The program will formulate the damping
matrix [C] as the sum of all the specified forms of damping. For more information about damping, see
Damping Matrices in the Mechanical APDL Theory Reference

The following tables show the type of damping supported for each structural analysis type:

• Table 1.1: Damping for Full Analyses (p. 3)


• Table 1.2: Damping for Modal and Mode Superposition Analyses (p. 3)


• Table 1.3: Damping for Damped Modal and QRDAMP Mode Superposition Analyses (p. 4)

Table 1.1: Damping for Full Analyses

Damping

Ratio

Viscoelast-

ic Material

Damping

Structur-

al Damp-

ing Coef-

ficient

Constant Structural

Damping Coefficient

Element

Damp-

ing ( 1 )

Rayleigh Damping

Mode-De-

pendent

Material-

Dependent

Material-

Depend-

ent

Material-

Depend-

ent

Material- Global

Depend-

ent

Global

MP,DM- TB,PRONY TB,SDAMP MDAMP

PR

COM- DMPSTR

BIN14,

MP,BETD

and

MP,ALPD

ALPHAD

and

BETAD MAT-

RIX27,

...

Static --- --- --- --- --- --- --- ---

Buckling --- --- --- --- --- --- --- ---

Substructure Yes Yes Yes --- --- --- --- Yes ( 2 )

Generation

Full Harmon- Yes Yes Yes Yes Yes Yes Yes ---

ic

Full Transi- Yes Yes Yes --- --- No ( 3 ) --- ---

ent

1. Includes superelement damping matrix.


2. Supported for Component Mode Synthesis (CMS) substructuring using fixed-interface method (CM-
   SOPT,FIX). See Component Mode Synthesis (CMS) for details.


3. In a full transient analysis, viscoelastic behavior is included in the constitutive relationship and not rep-
   resented via damping.

Table 1.2: Damping for Modal and Mode Superposition Analyses

Structural

Damping

Damping Ratio

Rayleigh Damp-

ing

Global

Mode-Depend-

ent 2

Material-Depend-

Global Global ent 2

DM- MP,DMPR MDAMP DMPSTR

PRAT

ALPHAD and

BETAD

Release 15.0 - © SAS IP, Inc. All rights reserved. - Contains proprietary and confidential information

Damping