/ALE/GRID/SPRING

Engine Keyword With this keyword it is possible to modify grid formulation parameters which initially be set in Starter keyword /ALE/GRID/SPRING. (Altair bar method for grid velocity computation).

Format

/ALE/GRID/SPRING

$Δ t_{0}$ $γ$ $η$ $υ$ V_min

Definitions

Field	Content	SI Unit Example
$Δ t_{0}$	Typical time step. (Real)	$[s]$
$γ$	Nonlinearity factor. Range: [0;1] (Real)
$η$	Damping coefficient. (Real)
$υ$	Shear scale factor. (Real)
`V`_min	Minimum volume for element deletion. (Real)	$[m^{3}]$

Comments

For more details, refer to ALE Grid Calculation in the User Guide and /ALE/GRID/SPRING in the Starter Reference Guide.
As of v12.0.210, /ALE/2 was replaced by /ALE/GRID/SPRING.
The $Δ t_{0}$ must be greater than the actual time step used in simulation.
The $γ$ is used to prevent the time step from dropping due to element collapse.
$γ$ = 1 means no nonlinear effects

0 < $γ$ < 1 means less weight is given to elements that do not collapse.
Default values are taken from a previous run.