Change tetrahedral mesh to hexahedral

I'm using Matlab 2019b. I have an stl file, that I read using STL File Reader version 1.2.0.0:

[f,v] = stlread('filename');

I see quite straightforward how to get a tetrahedral mesh out of it, but I need a hexahedral one. How can I obtain it? Or is there an easy way to convert a tetrahedral mesh into hexahedral?

Thank you for your time.

[darova]

How complicated your geomtry is? Is it possible to use griddata to interpolate it?

[Roberto Garza]

Here you find the geometry I'm working on:

Seen from the top, it has radial symmetry.

I'v tried to interpolate it by using griddata, but I'm having problems probably because the interpolating function I desire is not injective

[darova]

Please attach the data

[Roberto Garza]

Here they are!

[darova]

Is it correct? You want this crossection?

[Roberto Garza]

It is quite close to the expected one: the tooth in the lower part is due to points within the volume and not on the surface. But I think that omitting temporarily that internal disk, the same scipt gives the correct result.

[Salvatore Veneruso]

Hi, I make a tet FEMesh with generatemesh function. Is it possible to convert in hex mesh?

Answer 1

[darova]

Here is the way

Result

[Roberto Garza]

It still gives some problems in the rest of the surface, because some of the data belong to the internal part of the volume and not to its surface. But to tackle that, I can just omit the internal data during this step. But your change in the slope, solves the rest of the problem.

So, really thank you for your time!

[darova]

You are welcome

[Salvatore Veneruso]

Hi, I make a tet FEMesh with generatemesh function. Is it possible to convert in hex mesh? @darova