General viscous damping

The general viscous damping property implements a viscous damping between the source and target interface.

Definition

Source and target interfaces can be chosen arbitrarily.

Parameters

General link couplings can be parametrised in two modes: simple and advanced, which are described in the following.

Advanced mode

In the advanced mode, the user is prompted to supply four damping matrices, DSS, DST, DTS, and DTT. Following equation describes how the stiffness matrices define a coupling between the target and source interface, denoted by subscript T and S, respectively.

[FTFS]=[DTTDTSDSTDSS][y˙Ty˙S]

A list of symbols is shown in following table.

Symbol

Dimension

Meaning

FT

R6×1

Load vector to target interface

FS

R6×1

Load vector to target interface

y˙T

R6×1

Displacement vector of target interface

y˙S

R6×1

Displacement vector of source interface

DTT

R6×6

Damping matrix coupling target displacement and target load

DST

R6×6

Damping matrix coupling target displacement and source load

DTS

R6×6

Damping matrix coupling source displacement and target load

DSS

R6×6

Damping matrix coupling source displacement and source load

Simple mode

In the simple mode, a symmetric behaviour between target and source interface is implied. The four damping matrices are replaced by a single damping matrix D and applied to the coupling equation as follows:

[FTFS]=[DDDD][y˙Ty˙S]