Mesh Intersection Virtual Wind Tunnel

thavemann11_21105

Hello everyone,

 

I am having an issue with mesh intersections when running a full vehicle model inside Virtual Wind Tunnel. I have read up on all of the previous forums on this topic about how there cannot be any mesh intersections/penetrations, free edges/T-connections, or connectivity or duplicate element issues. In Hypermesh, I thought that I had resolved all of these issues because Hypermesh told me that there were not any of those issues in my model. However, after attempting to run the model in VWT, the meshintersection.nas file still popped up in my run directory. When importing this meshintersection.nas file into Hypermesh with the vehicle model, it appears that there are is a very small surface underneath the body of the vehicle that is attempting to be meshed. I have tried multiple geometry clean-up techniques and removed all intersections and free edges, however, these small elements beneath the vehicle still pop up. Is there some kind of geometry cleanup tool that can be used to stop these elements from forming underneath the vehicle?

 

Thanks for your help!

ydigit

There is one more check that I generally perform before exporting from HM, that is a small angles check. 

I start by repairing all elements with <2° initially. Once those are repaired <5° check/repair may or maynot be needed depending upon geometry.  This also helps to remove really small edges <1mm, as they are generally not needed. 

Also one more aspect is the level of tyre cut that you introduce, while positioning the vehicle in VWT. Sometimes increasing the chopped of portion of tyres, helps to avoid sharp angles at the intersection of tyres and the road.