volume¶
Module: solid
Category: nlconstraint
Type string: "volume"
Parameters¶
| Name | Description | Default | Units |
|---|---|---|---|
laugon |
laugon | false | [] |
augtol |
augtol | 0 | [] |
penalty |
penalty | 0 | [] |
Description¶
This feature implements a constraint that aims to maintain the volume enclosed by a user-specified surface using an constant pressure.
The constraint can be defined as,
\[
c = V_t - V_0 = 0
\]
The pressure is the Lagrange multiplier that enforces this constraint.
If the laugon parameter is 0, a penalty method is used.
\[
p = \varepsilon\,c=\varepsilon \left( V_t - V_0 \right)
\]
If laugon is set to 1, the augmented Lagrangian method is used.
\[
p^{k+1} = p^{k} + \Delta p
\]
where \(\Delta p = \varepsilon\,c\).