Element based surface tie not activated in Coupled Strucutural Acoustic Analysis.

[aurum]

I'm modelling a dam-foundation-reservoir system using acoustic elements to model reservoir domain.

I created an element based surface each for (Structure and foundation) and reservoir and used Tie Constraint to account for the interaction between the surfaces.

In my simulation results, I see that the tie constraints are not activated and the two surfaces move independently. It's also interesting to note that there's only a part of the surface tied between the dam and reservoir and the rest of it all is not activated.

I've attached an image of four different images. One highlighting the result with partially attached surface and other three showing the constraints and master and slave surfaces

Any help is appreciated. Thanks in advance.

 

[FEA way]

Try using Adjust slave surface initial position option and modify Position Tolerance if computed value doesn’t work. When you set everything up you can run datacheck and verify internally created sets that show both connected and unconnected regions for tie constraint.

 

[aurum]

Hi, I tried position tolerance and adjusting initial slave position, but the problem still persists. Do you think it has something to do with the different mesh sizes being tied together? I don't think so. I'd like to know your opinion here.

 

[FEA way]

Try further increasing position tolerance, it can be higher than the distance between surfaces. When there are large differences in mesh density of the tied surfaces, make sure that the one with finer mesh is assigned as slave surface.

 

[aurum]

Solved the problem by reducing the number of partition surfaces from eight to two and I still didn't understand the reason for the problem earlier. However, increasing position tolerance didn't seem to work. Thanks for the assistance