Learning Forum

[andrewthanga]

• Two 'Single ALE material' contained in a lagrangian shell conatiner and seperated by a lagrangian shell wall 
• Both the ale material and lagrangian material have same or equivalent density
• ALE materials do not mix
• Is it possible to model Fluid solid interaction or ALE and Lagrangian coupling, when both the ALE and Lagrangian material have same or equivalent density?  

[Alex Rycman]

 

Hello, 

It should be possible to set up fluid-solid interaction (FSI) or ALE-Lagrangian coupling in LS-DYNA for two single ALE materials, even when their densities match the surrounding Lagrangian shell container and they are separated by a Lagrangian shell wall.

• Assign elform = 11 to your ALE materials in the *SECTION_SOLID card, which is required for multi-material ALE formulations.

 

• Define each ALE region separately (e.g., ALE 1 and ALE 2) so that they do not mix and can be coupled independently to different Lagrangian surfaces.

 

• Use *SET_MULTI-MATERIAL_GROUP to create two distinct multi-material groups: one for ALE 1 and another for ALE 2. Each group will contain the respective ALE material part or part set. This setup is necessary for targeted coupling.

 

Configuring FSI Interaction Cards

• Depending on your ALE solver (standard or structured), use either *CONSTRAINED_LAGRANGE_IN_SOLID or *ALE_STRUCTURED_FSI to define the coupling between ALE and Lagrangian domains.

 

• For each interface, define a separate FSI interaction card:

 

• One card for coupling ALE 1 to the outer walls and bottom.

 

• One card for coupling ALE 1 to the inner walls.

 

• One card for coupling ALE 2 to the inner walls bottom.

 

• When specifying the MCOUP parameter in these cards, use a negative integer (e.g., MCOUP = -N), where N is the ID of the *SET_MULTI-MATERIAL_GROUP corresponding to the ALE region you want to couple. This ensures that only the specified ALE multi-material group is coupled to the designated Lagrangian surface

 

Thanks,
Alex 

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[andrewthanga]

 

 

Followed the above mentioned suggestions
ALE materials are not compressing/deforming the way they deformed while they are ran as lagrange
ALE Change in angle results are 2 to 3 times lower than Lagrange
1. Boundary conditions:
a) Bottom wall is in contact with another part which is fixed 
b) Downward Rotating load is applied on the top wall
c) Lagrangian outer and Inner walls have to deform with respect to the deformation of ALE materials (kind of sticking)

2. ALE materials are viscous materials
3. ALE_REFERENCE_SYSTEM_GROUP PRTYPE=1 is only passed the Boundary condition ‘c’, other PRTYPE have failed
Give some suggestions