Some Thoughts on Aerodynamic Shapes

[Mandilon]

I'm wondering (and will eventually check it out) how much air pressure is at the firewall end of the engine compartment. My idea is to restrict about 90-95% of the grille opening (and shape it more aerodynamically) and move the radiator to the end of the tractor.

[Kyleyadon]

This seems a good thread for this question. When it comes to aerodynamics, is a flat angle better than a curve? or is the opposite true? or does it only matter that the slope is gradual enough to allow airflow connection?

[3-Wheeler]

Originally Posted by Kyleyadon

This seems a good thread for this question. When it comes to aerodynamics, is a flat angle better than a curve? or is the opposite true? or does it only matter that the slope is gradual enough to allow airflow connection?

Take a look at the AeroHead Streamlining Template and many other related topics on this site. The streamlining template is the "mother shape" that all of us should aspire to achieve in our vehicle modifications.

Do some digging around, spend some time looking at various designs and such, and after a while you will be able to answer your question very well indeed.

Jim.

[3-Wheeler]

Another picture of the gorgeous VW 1L.

What a beautiful car!! I love it for it's aesthetics and function!!



Jim.

[winkosmosis]

Originally Posted by Otto

If GM's cfd lofting is so great, why does the Volt have such sucky drag in this day and age?

I always look at the front corners of the vehicle, where air flow is fastest and therefore drag per square inch is greatest of anyplace on the vehicle. If there are lumps & bumps or nooks & crannies there (as Volt has), it tells me the designers are pikers.

I thought the Volt had a lower Cd than the Prius

[jime57]

Originally Posted by winkosmosis

I thought the Volt had a lower Cd than the Prius

Only if you think Chevrolet's numbers are actually true. They claim to have compared the Volt and Prius in the GM wind tunnel. We only have GM's word for the results.

After all, GM has been so honest with numbers in the past

[euromodder]

Originally Posted by Kyleyadon

When it comes to aerodynamics, is a flat angle better than a curve? or is the opposite true? or does it only matter that the slope is gradual enough to allow airflow connection?

Sloping curves seem to work best, but you can approximate them using flat angles and still get most of the benefit.

You can see some rather straight edges appear or ever more cars, despite them having a low Cd. So a car doesn't need to be all curves.
Have a look at the Mercedes Bionic concept.
It's curves and sharp edges mixed together, with excellent Cd.

On the other hand, the curves can also be overdone and return a worse result than would be possible - see the VW New Beetle.

[kach22i]

Nice thread.

As far as the styling verses aerodynamic debate, the market rules.

People still favor coupes over hatchbacks in America.

[euromodder]

Originally Posted by kach22i

People still favor coupes over hatchbacks in America.

A nicely sloping roofline is easy to do on a coupé - Opel/Vauxhall Calibra style.

[kach22i]

Originally Posted by euromodder

A nicely sloping roofline is easy to do on a coupé - Opel/Vauxhall Calibra style.

They make it look easy, many others come out looking the same and bland.