Interpolate between adapted meshes

User Help
#1

Hello,

First of all I would like to really thank the developers of MMG. This seems to be good anisotropic mesh generator!

Next to introduce myself, I am Ajay a PhD student at RWTH Aachen. We develop high order DG codes for compressible flows. We are currently using MMG3d to test a few anisotropic mesh adaptation algorithms.

On this regard I had a question. I wanted to know if there is a way for me to interpolate a scalar value between an initial mesh and an adapted mesh.

I have an initial mesh and an associated anisotropic metric in a ‘.sol’ file. I also have a set of scalar values at the nodes of this initial mesh. I wanted to know if these scalar values can be interpolated to the new mesh generated using the sol file.

Best regards

Ajay

#2

Hello,

If you have two meshes and sol files, you could try and use FreeFem++ to make the interpolation. Just load the two meshes with readmesh into two different mesh variables. Then define the finite element spaces (up to P4 in 2D and P3 in 3D if I’m not mistaken) in FreeFem. If u1 a function on the first mesh and u2 on the second one, then the interpolation is made with a command like u2=u1. Take a look at the FreeFem documentation for more details.

Best regards,
Beni

#3

Hello,

Thanks a lot Beni. I will take a look at this.

I was hoping for a solution with MMG (similar to how BAMG does this for 2D) because this would mean I will have to interface our code with FreeFem++ independently. This is the a bit circuitous for my liking but I will take a look anyway.

Thanks a lot!

Best regards

Ajay

#4

Hello Ajay, Beni,

First, thank you for your answer Beni.

It is not possible to perform the solution interpolation with Mmg. We choose to not provide this tool because users often prefer to do it by themselves (they can choose the way to do it with respect to the numerical method that they use).

Best regards,

Algiane

#5