/DT/ALE
Engine Keyword Time step control for ALE or EULER cells.
Format
$\text{\Delta}{T}_{sca}$ $\text{\Delta}{T}_{\mathrm{min}}$
Definition
Field  Contents  SI Unit Example 

$\text{\Delta}{T}_{sca}$  Scale factor on
critical time step. Default = 0.5 

$\text{\Delta}{T}_{\mathrm{min}}$  Minimum time step. 
Comments
 If the ALE time step becomes less than $\text{\Delta}{T}_{\mathrm{min}}$ , then the simulation will stop and a restart file will be written.
 As of the 2018.0 release, /DT/BRICK and /DT/QUAD are only relevant for Lagrangian elements.
 As of the 2018.0 release, time step for ALE or EULER cells can only be controlled with /DT/ALE. This allows the time step control for the ALE cells to be different when you have both Lagrangian and ALE bricks in the input file.
 By default, scale factor $\text{\Delta}{T}_{sca}$
is 0.5 which is the recommended value for ALE or EULER
cells. As a result, if you did not use /DT or
/DT/BRICK or /DT/QUAD with
$\text{\Delta}{T}_{sca}$
=0.5, you will have by default, different time step from
version 2018.0. To retrieve your previous result, you must set the relevant time
step with /DT/ALE.
 2017.0 Engine File
 2018.0 Engine File
 /DT/BRICK with $\text{\Delta}{T}_{sca}$ =0.3
 Add /DT/ALE with $\text{\Delta}{T}_{sca}$ =0.3
 /DT/QUAD with $\text{\Delta}{T}_{sca}$ =0.0
 Add /DT/QUAD with $\text{\Delta}{T}_{sca}$ =0.9
 /DT with $\text{\Delta}{T}_{sca}$ =0.4
 Not applicable
 No time step control
 Add /DT/ALE with $\text{\Delta}{T}_{sca}$ =0.9 (3D case), or