Unable to create meshing for FEA

[nicola.lachowski]

Hello,

I'm having some problems doing an FEA on my project, I tried to do it using Inventor 2014 ( I designed my project with this version) and by using Ansys.

To design my bicycle frame i mostly used lofted surfaces that i thickend, as the idea was to create tubes.

My first problem is that I'm unable to generate a mesh on my frame, even if i followed all the steps shown in multiple tutorials..

I then tried to import it to Ansys, by converting the .ipt and .iam into .iges format, the problem there is that my surfaces were suddenly untrimmed... and Ansys has to have 1 single surface in order to create meshes. I have been able to generate a mesh for each tube seperatly, but as these tubes are not "bonded" together , (even if i used stich surface command) it is useless to make an anlysis. I also imported a version using only the "surfaces" created in inventor, but same problem, the tubes are not trimmed nor bonded together.

Could somebody explain me what my problem is ?

I would be very grateful if somebody could help me perform my FEA as it's an important project for university.

I uploaded the file on zippyshare as it exceeds the limit allowed on this forum

http://www2.zippyshare.com/v/41455277/file.html

Thanks in advance !

[JDMather]

That site looked like it was going to install unwanted software on my computer.

Post here to Autodesk 360

or

Find the red End of Part marker in the browser.
(End of Folded on sheet metal parts EOF)
Drag the red EOP to the top of the browser hiding all features.

Save the file with the EOP in a rolled up state.

Right click on the file name and select Send to Compressed (zipped) Folder.

Attach the resulting *.zip file here.

[nicola.lachowski]

Thanks for the quick reply, you can find the file here.

Thanks !

[blair]

Finding errors in these two areas:

[blair]

Inventor only does Isotropic materials, if you are expecting to have layers with directions of lay-up you won't get the results in Inventor. I'll try in Simulation Mechanical and see if it meshes there.

[nicola.lachowski]

Thanks for the quick reply !

The error at the bottom bracket ( the aluminum insert and the rear dropouts ( the "holes") are features i made using a solid extrusion and not a surface loft+ thicken. Could this be the reason why ?

I wanted to make a mesh using a model in aluminum at first and then one using carbon fiber, but none of them will fillet.

I'll try to modify the model by making a surface loft and thicken, but i don't understand why this creates a problem as I'm able to mesh a simple beam that i made using a solid extrusion just to test..

[JDMather]

I see Blair already responded - but I would clean up these areas (might be others) before attempting to mesh in any program.

[nicola.lachowski]

I havent't noticed that, thanks !

how did you do to have this kind of view ?

Thanks a lot for the help!

[JDMather]

Went to a section view.

After posting that image I found other areas of concern.

[nicola.lachowski]

at the risk of appearing stupid but... how did you do to have the fault sticking out in another colour ?
I have found the way to use a section view but not how to highlight the colors. And in the help function it shows the different section views one can do found nothing that shows what you showed me. I tried every option in the "appearance" window but can't come to the same you did.

I assume the best way to clean this up is by deleting all of my "thicken" features and ensuring that the surfaces are better trimmed ?

I really apreciate the help you are giving

[JDMather]

I found the problems the old-fashion way.   Eyeball inspection.  Then I right clicked on the faces and changed the Properties to red color (after first changing the overall part color).

There was no automagical tool involved.

[blair]

What's funny, is that Inventor through up errors on the back axle connection and at the base of the seat down tube. Simulation Mechanical was having a problem with the main lower down tube. If it doesn't mesh in Sim-Mech, it has tools to edit the surface mesh which allows one to clear up most issues. In this case, delete the interior features and apply a boundry mesh patch.

[nicola.lachowski]

I'm afraid I'm not entirely following you blair..

I tried to delete all of my thicken features to try to trim my surfaces better and stitch them together (+apply fillets) and then thicken the whole single surface ( the whole frame being the entire surface)

however i now can't seem to stich every surface together now.

I'm downloading SIim-Mech at the moment, I will try to mesh my model there when I deleted my interior features as you suggested.

[blair]

Simulation Mech has surface repair tools in it that allow for repair of surfaces to aid in meshing. This is not done in Inventor at all but in Simulation Mechanical.

[nicola.lachowski]

ok so i restarted from scratch, just copied most of the sketches and making some adjustements.

I have been able to make a nice uniform surface by stitching all of the surfaces together, now I wanted to thicken it but it doesn't work...

"does not produce a meaningfull result"..  The upper horizontal tube seems to be the problem, but i don't know why ... ?

could somebody also tell my how I could trim the chain stays better so that there is no part sticking out inside the bottom bracket ?

Thanks !