Aerodynamic flow simulations (aero nerd heaven)

Dream mod for my Previa is a boat tail.  I prepared a few videos to see if the flow works out.  This is from a free program called Flow Illustrator.

The flow is the most stable on the boat tail version and wake and mixing are the smallest.

 

This view shows a deflector wing and belly pan.  Too much mixing and unstable wake behind the wing.

Here is the stock simulation.  Note the turbulent mixing under the van as well as the wavy, unstable large wake.

My next major project for the Previa will be an under belly pan. 

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