Very basic question about libmesh, mesh generation, and using MOOSE

[AnTu Xie]

I'm completely new to MOOSE, Libmesh, and the world simulation in general, so I apologize if I'm just missing something quite basic.

I've installed/compiled MOOSE and Libmesh on my system, and right now am just trying to understand the Libmesh examples to build a simple mesh. So far, however, I can't seem to actually even reach step 1, which I consider to be building a simple mesh using the libmesh examples. Are these examples in the libmesh files supposed to be working?

$ ls

Makefile.am Makefile.old run.sh

Makefile.in introduction_ex1.C

$ make

make: *** No targets specified and no makefile found.  Stop.

Nothing I do seems to actually work, though if I just follow the 1st MOOSE tutorial step, everything works and I'm able to see the mug's heat transfer. Of course, that doesn't really help me generate my own mesh.

What I really want to do is generate a mesh from a 3D array of points, either 0 or 1, where 1 represents a filled space and 0 represents an empty space. In a way, it is already a mesh, but I need to generate them in a way that is interpretable by MOOSE, and I don't have access to a Exodus II mesh-generating piece of software.

Thank you for any clarity you can provide, I am quite confused on what I should really be trying to do.

[Peterson, JW]

On Tue, Aug 11, 2015 at 12:54 AM, AnTu Xie <ant...@gmail.com> wrote:

I'm completely new to MOOSE, Libmesh, and the world simulation in general, so I apologize if I'm just missing something quite basic.

I've installed/compiled MOOSE and Libmesh on my system, and right now am just trying to understand the Libmesh examples to build a simple mesh. So far, however, I can't seem to actually even reach step 1, which I consider to be building a simple mesh using the libmesh examples. Are these examples in the libmesh files supposed to be working?

$ ls

Makefile.am Makefile.old run.sh

Makefile.in introduction_ex1.C

$ make

make: *** No targets specified and no makefile found.  Stop.

The libmesh examples are used differently depending on whether you are in the "build" directory or the "installed" directory.  From what you pasted above, it looks like you are in the build directory, so you would type 'make check' to run the relevant example.

Generally speaking, however, you don't use libmesh to generate custom meshes -- you use a mesh generator.

 

Nothing I do seems to actually work, though if I just follow the 1st MOOSE tutorial step, everything works and I'm able to see the mug's heat transfer. Of course, that doesn't really help me generate my own mesh.

This mesh was generated in Cubit.

 

What I really want to do is generate a mesh from a 3D array of points, either 0 or 1, where 1 represents a filled space and 0 represents an empty space. In a way, it is already a mesh, but I need to generate them in a way that is interpretable by MOOSE, and I don't have access to a Exodus II mesh-generating piece of software.

If you have a point-cloud you want to mesh rather than e.g. a geometry description, you are somewhat limited in your options.  You might be able to use either Gmsh or Tetgen, although we don't provide support for either of these tools because we aren't experts in them.

--

John

[Peterson, JW]

On Thu, Aug 13, 2015 at 10:42 AM, Peterson, JW <jw.pe...@inl.gov> wrote:

On Tue, Aug 11, 2015 at 12:54 AM, AnTu Xie <ant...@gmail.com> wrote:

I'm completely new to MOOSE, Libmesh, and the world simulation in general, so I apologize if I'm just missing something quite basic.

I've installed/compiled MOOSE and Libmesh on my system, and right now am just trying to understand the Libmesh examples to build a simple mesh. So far, however, I can't seem to actually even reach step 1, which I consider to be building a simple mesh using the libmesh examples. Are these examples in the libmesh files supposed to be working?

$ ls

Makefile.am Makefile.old run.sh

Makefile.in introduction_ex1.C

$ make

make: *** No targets specified and no makefile found.  Stop.

The libmesh examples are used differently depending on whether you are in the "build" directory or the "installed" directory.  From what you pasted above, it looks like you are in the build directory,

Actually, I take that back, it looks like you are in the source directory.  The libmesh examples cannot be built or executed from the source directory.  Trying changing directories to build/examples/introduction/introduction_ex1 and running 'make check'.

--

John