Discussion Forum

Hi,

I imported a frame model(Assembly) using livelink for ProE and saved the model in COMSOL 4.1. I'm trying to run a bacis static load study on this frame but while Meshing it gives me errors which dont let me run the study. the Error say Free tetrahedan and uder that there are multiple errors and warnings that say mesh cannot be created. Can someone please help me solve this issue.... and also what would be the best way to import PRO-E complex models/large assemblies.

Thanks in advance

You need to post your file if you want specific help. Too hard to diagnose a problem/recommend a solution just by a description sometimes.

Thanks Dennis I tried to but the file size is too big to attach :(

Would clearing the solution reduce the file size? (File>Clear solutions)

Would clearing the solution reduce the file size? (File>Clear solutions)

Yes clear the solutions/results and then your file size will drop.

It worked file attached

I took a look at your file. I did a default mesh. While it did not mesh to calculate a solution, what it did come up with is that the number of elements was 549,000 or so. That is quite a bit. You will need a 64bit computer with decent RAM for that amount of elements. I also noticed in the mesh (see images) that you have a lot of little elements. Now it may be that when you export the file from your CAD program it is adding a bunch of things that you do not need. There are holes in your structure that maybe you do not need. You could remove those (unless they are critical to your analysis). When building models use only what you need because adding other things can make the mesh difficult and too intense. In the second image file, I have circled a couple areas where the mesh is dense. I can also see curved areas in the geometry that maybe don't need to be. It is just that these little things add up. The image 'mesh3' shows a very dense area. Even though comsol is importing it fine there may be areas in the geometry where sides are not attached together completely that was done by the CAD pkg. COMSOL likes it when everything lines up mathematically correct and will do odd things when you are off by very little amounts. I have seen things not mesh well because I either had a thin area or two elements were off by fractions of mm.

My suggestions are this:

1) Draw one piece of your structure in your CAD package and then import it in to comsol. Then manually draw in the same thing using comsol and compare the meshes. Repeat for two elements (and etc) and see if you can tell how the CAD tool is affecting the mesh. Make sure you draw things that intersect so that you can see how the mesh is being generated. While I would like to tell you that you can use the geometry you have, at this point it is beyond my mesh abilities to fix this or suggest things to do. One thing you can try is go into the CAD defeaturing and repair (right click geometry node) and see if removing elements help. This is trial and error on your part.

2) Another option is to draw this in the comsol gui. Yeah, I know, you paid for the livelink and it should work. If it was me, I would try and do this. You are limited what you can do when you import in other non-native geometries. I can see why you would want to import this but it is what it is.

3) If you are on paid support, send the file in and see if they can work it out.

4) If you have any symmetry in your problem, exploit it. It will simplify your life more.

Someone else may be able to help you here that knows some tricks.

Thank you Dennis.....really appreciate it :)