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Originally Posted by julien.decharentenay
I totally agree with you. It is quite an evolving field, and it is difficult to keep up to date with research and best practice.
From a methodology point of view, there has been some interested development with the so-called meshless models (I think that Autodesk Falcon is one of them) - but I have not used any and find it difficult to make the difference between claims and reality.
This being considered, simple models using combination of empirical/physical test/models can be far more accurate than very advanced models... It is often about validation... validation... validation... and experience...
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Even in wind tunnel tests of 3-D models things get weird and contextual.
Professor Alberto Morelli developed a CFD tool from a 1947 NACA (NASA) numerical algorithm.
In 1976 a scale model of Morelli's sent an earthquake and aftershocks through the aero community,registering Cd 0.161 with mild tail truncation.
The thing that wasn't mentioned was that the body was not at a practical ground clearance.
In 1978 the Italian govt. funded a full-scale demonstrator and with wheels,and realistic ground clearance,the car registered Cd 0.35,much higher than what was anticipated.
Aptera attempted to capitalize on Morelli's form and to my knowledge attained no remarkable Cd when compared to more old school,retro,vintage,antique,or Pleistocenic forms.
PS If my memory serves me,a NOVA broadcast showed a computer graphic simulation of cosmic radiation deflection by Earth's magnetosphere,creating a classical teardrop form.