Information on Aero - particularly under body

[TMcRally]

Hi all

Can anyone recomend good reading info or advise on down force created by plates etc under car. We are permitted under body protection and provided it does not include any component which can not reasnobly be explained as protection we can have it. By that I mean we can not have air vanes or channels etc, but we can extend a plate backwards from the front air dam (small factory option part) back but we can't extend forward of the air dam.

We can also have protection for the fuel tank and rear diff, so I'm guessing there is a reasonable amount of down force available which I'm not making use of.

Thanks

 

[hemipanter]

Shortly I could say that a flat bottom at a ride height of 3 1/2" in the middle of the car and a rake of 1 1/4" over the axles distance, will produce about -100mm of water @ 100mph, in the centre portion of the bottom. All according to my "real life" testing. No rake was zero pressure.
This could compare to a possible raise of pressure without a flat belly pan.
Regards
Goran

 

[hemipanter]

Shortly I could say that a flat bottom at a ride height of 3 1/2" in the middle of the car and a rake of 1 1/4" over the axles distance, will produce about 100mm of water @ 100mph, in the centre portion of the bottom. All according to my "real life" testing. No rake was zero pressure.
This could compare to a possible raise of pressure without a flat belly pan.
Regards
Goran

 

[GregLocock]

Try Joseph Katz, obvious title.



Cheers

Greg Locock

SIGlease see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[carnage1]

Would you recommend this as a good engineering resource to add to my library? I don't currently have an aero specific resource.

Luck is a difficult thing to verify and therefore should be tested often. - Me

 

[GregLocock]

If you are racing, yes. It is only 35 bucks from Amazon. Katz has a great chapter on wing theory for example, working from 2D flow through to short span airfoils at high AoA with endplates and gurney flaps.


If you are more into production vehicles then Hucho is better. Both are really rather broad surveys, the references are the most useful thing.




Cheers

Greg Locock

SIGlease see FAQ731-376 for tips on how to make the best use of Eng-Tips.