Anyone have access to SAE publications?, underbody diffuser design papers Options

[TonyAKAVW]

I found an interesting literature review concerning underbody diffusers and there is a list of references, some of which are through the SAE.

Here's the article, and if anyone can get me electronic copies of the articles or knows of a way, I'd appreciate it.

http://www.tech.volvo.se/ivs/courses/kurs_...ero_rapp_sp.pdf


Thanks

Tony

[TonyAKAVW]

QUOTE

well... yes and no. Bernoulli's says that airspeed increases/ decreases with the size of the container. But a diffuser isn't necessarily about changing airspeed. It's more about controlling direction of air to minimize turbulence. At least this is my understanding.

That's partially correct. In the end it is all about reducing pressure under the car which is effectively downforce. The shape of the channel is made such that the air pressure and velocity are kept low and high respectively. This works best (or maybe at all) with laminar flow versus turbulent flow, simply because turbulent air moves slower. From what I've read so far though, maintining laminar flow on any part of a vehicle is next to impossible, so its all an approximation anyway. In any case, the air immediately exiting the venturi is going to to be massively turbulent as that is the low pressure condition.

So really it isn't about direction, but about air velocity/pressure.

-Tony