[jnagy]

Comments and questions are welcomed on the article Ahmed et al. A Modified Overset Method in OpenFOAM for Simultaneous Motion and Deformation: A Case Study of a Flexible Flapping Foil, April 2024, OpenFOAM Journal, https://doi.org/10.51560/ofj.v4.96

[Tianyz]

Originally Posted by jnagy

Comments and questions are welcomed on the article Ahmed et al. A Modified Overset Method in OpenFOAM for Simultaneous Motion and Deformation: A Case Study of a Flexible Flapping Foil, April 2024, OpenFOAM Journal, https://doi.org/10.51560/ofj.v4.96

Hi Ahmed,

Your work is really interesting! I have one question for you. By checking the source code, you try to modify the current the overset library to identify and then specify a certain zone to apply the mesh motion and deformation. I noticed that you use the solidBodyDisplacementLaplacian as an example, so does the other mesh motion solver be supported? For example displacementLaplacian. Which will adjust the deformation of the whole overset domain when it terms to the large deformation, including the boundary of the overset mesh.

Best,
Tian

[Karim ahmed]

Hello Tian,
Thank you for your interest. Yes I already worked with the displacement Laplacian using our modified solver and it run perfectly fine. However, It will deform a certain patch inside the overset mesh , but i never tried to deform the boundary of the overset mesh itself. Of course when you use a uniform diffusivity this move the boundaries of the overset a little bit when you have large deformation at an interior patch.
Regards,
Karim

[Jim1310]

Hello Ahmed,


First of all i want to thank you for your valuable contribution in the openfoam community.
I would like to share a problem which i think is related to your research. For a simulation that i want to run i have concluded that an overset mesh where the background mesh is deformed would be useful. More specifically i aim to simulate the roll motion of a ship (which can potentially be extreme, therefore overset mesh should be used) in a wave flume. The waves in the wave flume are going to be generated from a wave maker (therefore the background mesh should be deformed). Do you know if any such mesh capability already exists?


Kind regards,
Dimitris

[AhmedHamada]

Originally Posted by Jim1310

Hello Ahmed,


First of all i want to thank you for your valuable contribution in the openfoam community.
I would like to share a problem which i think is related to your research. For a simulation that i want to run i have concluded that an overset mesh where the background mesh is deformed would be useful. More specifically i aim to simulate the roll motion of a ship (which can potentially be extreme, therefore overset mesh should be used) in a wave flume. The waves in the wave flume are going to be generated from a wave maker (therefore the background mesh should be deformed). Do you know if any such mesh capability already exists?


Kind regards,
Dimitris

Hi Dimitris,
You can conduct this in multiple ways:
1) use some wave model instead of the wave maker.

If you want to add the wave make motion in the simulation
2) use multiple overset (Front) meshes, one for the hull and another for the wave maker.
or
3) The background mesh can be deformed as the zones are defined in this modified overset. So you need to name the background and add the wave maker deformation to it, similar to the front mesh defromation. Check the dynamicOversetZoneFvMesh/Tutorial/LE_Case/backGround/constant
/dynamicMeshDict
https://github.com/AhmedAHamada/dyna...ynamicMeshDict

[Jim1310]

Hello Ahmed,


I had tried introducing deformation in the background mesh to accommodate for the wave maker movement while at the same time i wanted to have a free-floating object in the middle of the tank and have the overset mesh moving like a rigid body. This required the use of calculated boundary condition which always led to an error when the deformation of the background mesh had to be calculated. I subsequently modified the calculated boundary condition to 'trick' the solver. I have documented the error and the solution in this post Overset with moving domain , number 15 and 16.