Moving grid with deformation

Is preCICE for me?
1

Hi,

I am trying to solve some moving grid with deformation problems. I tried to show using a simple 2D example. I have attached it. So I have a horizontal wood plank attached to a wall. The wall is prescribed to slide up/down vertically and so the plank moves too. I would like to use FSI to determine how much the plank will deform.

For this problem, we can use the displacementLaplacian solver to deform the entire grid. However, I wonder if we can move the entire grid for the prescribed motion and only use the displacementLaplacian solver to deform the grid for the plank deformation. So there’s 2 separate motions

This is similar in some sense to what JulianSchl is doing https://precice.discourse.group/t/rotational-movements-with-precice-and-openfoam-using-solidbody-solver-instead-of-displacementlaplacian-solver/622

However, there’s no update regarding their develpment.

preCICE qn
preCICE qn800×600 7.4 KB

Thanks.

2

Hi,
have you tried to look at the tutorials here? There is an example with solids4foam using overset. Maybe you can adapt it to your case.
Claudio

3

Hi, I think I have seen it before.

But is it possible to do it without overset? Cos my actual problem involves moving large distances and hence overset is not that efficient.

4

Hi, probably it’s not, but it should work fine if it is “2D”. Alternatively, could you set up some whole mesh movement, like in the sloshing examples? It depends on the boundary conditions you want to set up. I have never tried, it is just a guess.

5

I just tried the overset example. However, after I downloaded it and run, it doesn’t seem to work. Running ./Allrun got some results, but on paraview I don’t see any motion. If I run separately with 2 terminals using ./Allrun.fluid and ./Allrun.solid, the fluid one seems to run by itself while the solid one just give:

Rotating points
    about (1 0 0)
    angle 90
Rotating points by (1 0 0 0 2.22045e-16 -1 0 1 2.22045e-16)
Writing points into directory "constant/polyMesh"


End

Running solids4Foam on /home/user/Flapping_OF_2D_tmp/precice-tutorials/flexibleOversetCylinder/solid
Removing time directories without results

Is there some errors somewhere?

6

Hello, quarkz
If you can describe your case in more detail, I believe someone can help you make better suggestions, including me.
For example:
size of calculation area, the amplitude of the boundary motion, the given displacement boundary conditions, and it would be better if several pictures could be given indicating the limit position of the solid region in the flow field.
With best wishes.
xiangxiang

7

Hi daxiangxiang, actually I don’t want to make my problem too complicated and confusing. Basically, I want a moving grid which moves together with the body of interest. At the same time I want to prescribed some deformation to the body or let FSI deform the body due to the motion. As the deformation can be quite big, I would require to use RBF to deform the mesh. I use my simple problem earlier to check if it can be done. If so, then it’s doable with precice. Thanks