I have been thinking of this formula for a while. To me i don't think this type of application would work to well in a formula car but maybe work to an advantage on a gt car. I agree with what a commenter(just_a_fan) posted early on, the tools and accessories needed would take up space and add extra weight which would mean the car would have to produce more torque to move at the same speed it currently did(before this mod).
my idea behind using frequency processing in an aerodynamic way is to follow the process of "energy dumping" which is a slang term for releasing the energy load in a stored medium. where i'm trying to go with this is, When a car is increasing its velocity it also increases drag. This drag works as a stored energy or weight on the car, so if you where to use sound frequency(particularly low FQ) to resonate the frequency position of the car to release the drag or disturb the drag flow(which would separate the load away from the car), in practice the car should create a Vacuum seal or bubble in its air space where it decreases or eliminates drag in the surrounding area.
where i see this being put into place is with the use of KERS in passing situations or a defensive situation to subdue overtakes(dangerous outcomes). KERS in current regulation(FIA GP) can only be used in a designated strait of a track. This is where most cars pick up the most drag while increasing speed, but also this is when a driver is increasing speed before making a PASS,in this "slip stream" approach they are behind the back wash of the car in front which is good in decreasing there cars drag. but as soon as they leave that stream the car instantly picks up that drag on the frontal portion of the car creating instability(loss of downforce, uneven tire load) and can lead to an unsuccessful pass.now this slip stream technique isn't much of a value in most formula cars simply because they don't have a large drag area(oppose to a GT,DTM,Nascar or truck), so a Grand Prix or prototype car cant really take advantage of this technique to actively.
But it is in this occasion where the overtaking or defensive car can deploy a kind of "energy bump" i would like to call it a subsonic bump or drag release, where in a frequency pattern can eliminate or diffuse that drag so for example the overtakers car stability is undisturbed as if they never left the slip stream of the car in front of them, which would result a increase in strait line stability, increase of velocity for the pass and still being able to keep down force in the front of the car for the braking at the end of the strait. This design should mimic the exhaust blow which was created to decrease drag. But it should work even greater because the drag decrease is not limited to only the rear of the car but instead the front and central gravity allowing the ENTIRE car to reduce drag.
So with that i try to make clear this is attended to work along side of KERS and could be a replacement for Exhaust blowing.This feature would not likely be useful for any other area besides the straits. In corners you need down force. The energy bump would not increase downforce, In most cases it would upset the aerodynamic load, and in my estimates this was the problem with exhaust blowing,when exiting corners and other instability issues.
i think all in all the idea of using sound is, to mimic the thermal dynamic aspect of "exhaust blowing" or pressure diffusing. but cons of this style is much more likely to happen then the positive aspects. thus my reason why it wouldn't work in F1.
MZIVTNS - sound waves can be reflected, but the sound wave from the sound origin does not reflect it is diffused through mass, one of the reasons why the sound wave extension is measured in spl db's. from the point of origin the sound is moved across the mass area within its zone.