/DT/Eltyp/Iflag

Engine Keyword Time step for select entities.

Format

/DT/Eltyp/Iflag

Δ T sca Δ T min

grnd_ID

Definitions

Data Description SI Unit Example
Eltyp Entity selection:
BRICK
Brick elements
QUAD
Quad elements
SHELL
Shell elements
SH_3N
Triangular shell elements
TRUSS
Truss elements
BEAM
Beam elements
SPRING
Spring elements
AIRBAG
Airbag
FVMBAG
Finite Volume Method airbag for monitored volumes type /FVMBAG or /FVMBAG1 only.
/DT/FVMBAG means that if dt<dtmin and volume < 10 * the minimum volume used for global merge the finite volume is merged. This is the strategy used in version 12.0.223.
The Δ T sca and Δ T min can be defined to insure stability and a minimum time step size by triggering additional finite volume merges when the FVMBAG entity penalizes the computation.
/DT/FVMBAG/1 means that if dt<dtmin the finite volume is merged.
INTER
Interface (TYPE7 only). Only concerns interface TYPE7 time step.
NODA
Nodes
Activates nodal time step computation. With this option, the computation of each cycle is slightly more expensive, but the time step can be higher, mainly for non-optimized meshes.
 
Iflag Node group flag 1  
Δ T sca Scale factor on time step for the option defined by Eltyp.  
Δ T min Minimum time step for the option defined by Eltyp. 2  
grnd_ID Node group identifier.

Read only if Eltyp is NODA and Iflag =1.

 

Comments

  1. The Iflag can be only used with Eltyp=NODA.
    • If Iflag =1, only the nodes belonging the node group grnd_ID are affected.
    • If Iflag =0, all nodes are affected.
  2. If Eltyp is BEAM, TRUSS, SPRING, NODA or INTER, the value of Δ T min has no effect.