View Single Post
  #14  
Old August 30th 2003, 10:55
chigger chigger is offline
Registered User
 
Join Date: Sep 2002
Posts: 142
I have looked at this subject for quite a while. One of the problems with looking at other race cars is that the aerodynamics are often dictated by the rules and not the possibilities of the engineering. Most of that you see is the car designers ideas to get the most out of what the rules allow.
For example the vents to the rear and top of the fenders is to relieve lift in the fender wells as a result of the of the GT racers going airborne. The rules made these mandantory. They do decrease lift, but also create drag.
The flat pan is also rule mandated. It is not the best undercar design, but it is required. Since I am not rule directed I have come up with some interesting ideas.
You have to approach the aero as a package not just individual parts. The following is some of my ideas, many which are hard to explain quickly without pictures.
Closing all the air catcher holes around the front end is a start. It is good to keep air out of the box section where the steering box and MC are located. To the front of the fender a plate can be placed in the fender to keep air from getting into the fender well. The rear of the well also has a plate used to direct air out of holes in the fender at about a 45 to 60 degree angle. This would be a lot of work for limited benefit unless you are going really fast. The same applies to the rear fender well.
A front spoiler is a necessity. Sorry it just is. You can use it to keep air from under the car or to channel air to your underbody aero mods. Another mod for the front is small strakes (triangular plates set at angles to the ground) on the outside of the fenders. Effective but obvious.
A rear spoiler is a necessity also to break the rear lift. It doesn't have to be very big. The angle is important. It and the underbody difusers output should create a defined flow much like using sheet metal. If drawn it would look like a pointed tail coming off the rear of the car. The spoiler can also be used to pump a wing. In order to work properly the wing must be positioned over the ground with no car parts under it and as low as possible. This would look quite weird and work very well, maybe to well as it might lift the front end. Raising the wing until the airflow from the spoiler flows below the wing would pump the wing and perhaps create the same effect.
At the least I believe you need both a spoiler to keep air from under the front and a spoiler to break the lift in the rear. The rear spoiler is going to have to be used. Most of the rear spoilers I have looked at don't work right or they have other problems like blocking the cooling vents.
I have some really good ideas on modifying the pan which work very well. I have tested them with a model and I was impressed with the downforce and the self correcting aspect. It seemed to create more downforce if one of the ends or sides lifted causing it to bring down the raised side or end. I will have to draw up some pictures to explain it. It is quite simple to make and is totally hidden under the car.
These are some, but not all of the areas I have been investigating. I hope some of it is of help.
Reply With Quote