regarding the first topic (Watertightness): Within Inventor, are all parts real solids or are they surfaces? After your upload to SimScale, the vortex generators are proper solids, but all the rest of the parts of the truck are surfaces. There are two ways to make sure that the model is watertight:
- Make all parts solids within your CAD system. Solids are by definition a closed shell/surface, so this will work
- Make sure your shells / surfaces are closed. This would mean that you merge (Boolean Union) all of the surface parts to one shell which
I’m not so familiar with Inventor, but there are also dedicated tools in some CAD systems for such operations. Last but not least, you could also create the virtual wind tunnel geometry in your CAD system. So create a large box and subtract the truck from it to get the flow domain. That way you can make sure yourself within the CAD system that the air domain is what you want it to be.
Regarding the MRF zone: No unfortunately, there is no visualization of the rotating center currently within SimScale. The safest way is to determine the coordinates of the center point of your wheel within your CAD system and then enter it into SimScale.
I hope that helps!