CustomViscosity

Viscous Material Using Custom Model

Reference:

1. 10.1016/j.ymssp.2021.108795

Syntax

material CustomViscosity (1) (2)
# (1) int, unique material tag
# (2) int, expression tag

Remarks

The expression needed takes strain and strain rate as the inputs and returns the damping coefficient and its derivatives as the outputs.

The input size shall be 2 and the output size shall be 3.

Example

Imaging to model the linear viscous material such that

$$\sigma=1234\dot{\epsilon},$$

One can define the expression as

expression SimpleVector 1 x|2 y|3 y[0]:=1234*x[1];y[1]:=0;y[2]:=1234;

The strain maps to x[0] and the strain rate maps to x[1].

The stress output maps to y[0] and its derivatives regarding strain and strain rate maps to y[1] and y[2] respectively.