/ALE/BCS

Block Format Keyword Describes the ALE boundary conditions.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
/ALE/BCS/bcs_ID
bcs_title
Grilag skew_ID grnd_ID              

Definitions

Field Contents SI Unit Example
bcs_ID Boundary conditions block identifier.

(Integer, maximum 10 digits)

 
bcs_title Boundary condition block title.

(Character, maximum 100 characters)

 
Grilag Codes for grid velocity and Lagrange.
= 0
Free DOF
= 1
Fixed DOF - the node is Lagrangian in the corresponding direction i.e. Wi = Vi.

(6 Booleans)

 
skew_ID Skew identifier.

(Integer)

 
grnd_ID Node group to which boundary conditions are applied.

(Integer)

 

Codes for Grid Velocity and Lagrange: Grilag

(1)-1 (1)-2 (1)-3 (1)-4 (1)-5 (1)-6 (1)-7 (1)-8 (1)-9 (1)-10
      WX WY WZ   LX LY LZ

Definitions

Field Contents SI Unit Example
WX Code for grid velocity WX
= 0
Free DOF
= 1
Fixed DOF

(Boolean)

 
WY Code for grid velocity WY
= 0
Free DOF
= 1
Fixed DOF

(Boolean)

 
WZ Code for grid velocity WZ
= 0
Free DOF
= 1
Fixed DOF

(Boolean)

 
LX Lagrange code WX = VX
= 0
Free DOF
= 1
Fixed DOF

(Boolean)

 
LY Lagrange code WY = VY
= 0
Free DOF
= 1
Fixed DOF

(Boolean)

 
LZ Lagrange code WZ = VZ
= 0
Free DOF
= 1
Fixed DOF

(Boolean)

 

Comments

  1. If a node is constraint with ALE boundary conditions and classical boundary conditions (/BCS), both boundary conditions must be set is the same skew system (skew_ID).
  2. The grnd_ID input is obligatory. The boundary conditions will only be applied to nodes belonging to a node group.
  3. Detail input format for Grilag is shown above. The three individual codes (one per direction), must be right justified in the ten character fields used by the variable Grilag.