>
> Good morning Paul and group
>
> Anyone watching the F1 race this morning?  I am watching it
> live :))
>
> Marc Joseph

> Yep. Notice that they speak in Fahrenheit and psi :)
>
> Paul Lamar

Paul,

I've been watching these races for years...  But, year after year, one
thing is constant, the aerodynamic shape of these cars is always
different.  They have a lot of imagination and creativity went it comes
to shape and form to create down force.  But this year it is so
incredibly different.  They have at some places mini-vortex-generators.
Also behind the driver there is a fin?  My question:  Is aerodynamic in
it infancy stage or so advance that many tuning possibilities exist to
play with?

Marc Joseph

An open wheel race car has a lot of stuff going on. Air has adhesion and it sticks to the rotating tires among other things causing chaos. Think of air as thin Molasses. Not to mention all of the suspension bits stuck out into the air stream. A house fly does not fly per se. It swims :) A Formula one car is not quite a hot knife cutting butter. Those small canards and elephant ears are an attempt to micro manage the air molecules and getting them all going in the right direction within the FAI rules. Then you have the cooling drag issues. Several of those teams own their own moving ground plane wind tunnels. If you are spending 800 million U.S. a year on the program (Toyota) what is $100 million U.S. for a wind tunnel have to do with it? :)

The fin behind the driver does nothing for yaw stability until the car is going side ways at over a 45 degree yaw angle or so due to it's low aspect ratio. You only get those kinds yaw angles after you have spun out.  When the car is yawing 90 degrees to the air stream in a spin the fin could cut the lift over the rear of the car increasing the rear tire down and side force tending to straighten out the car.

There may be a vertical axis vortex behind the ram air box which the fin might tend to straighten out before the air impacts the rear wing. All this is mostly supposition on my part. I am not privy to the wind tunnel data.

BTW If you want to see a passenger car optimized for aerodynamic drag take a close look a Toyota Prius. Most people who think the Prius's good mileage has to do solely with the hybrid drive system are mistaken. For that reason the car is a partial fraud :)


Paul Lamar