![Tip leakage flow. [654x428 - 83KB]](https://pic8.co/sh/oSXdqH.png){kind=link}
Something I'm doing to my car. You see, if you have a wheel travelling in a straight line, there is an equal amount of turbulence and tire wake, however, if you toe out the wheel, something interesting happens. The tire sheds a jetting vortex between the now high pressure inner side of the wheel and the lower pressure outer side of the wheel. This vortex is extremely stable and creates laminar flow as opposed to the nasty turbulent wake a toed in or 0 toe wheel produces. Instead of making extreme alignment changes, I'm using turning vanes, and alignment settings to have in effect an extreme toed out wheel. The jetting vortex plays nicely with the front splitter and rear diffuser, and so the aim is to use turning vanes so that air hits the inside of the wheel just right to get the strongest vortex.
It's not so easy because the effect is useless in a straight line, and getting it to work when the car is in yaw/cornering is very difficult because the size of the turning vanes is limited due to space. So the vanes have to be designed precisely to align the airflow under yaw conditions.
I'm just researching all the perturbations that could affect the flow field, that way I can compensate for them to get the desired flow pattern.
Interesting. I know this is not in line with your topic, but I use negative pressure in the wheel arch downstream of the intercooler for more flow through the cooler. You can confirm your modelling, or proof of concept with some surgical tubing piped to a a minihelic guage in the cabin. https://www.dwyer-inst.com/Product/Pressure/DifferentialPressure/Gages/Series2-5000
How many degrees of toe out are you?from a tire wear, straight line stability and maximum cornering perspective, you may have negative side effects. Have you thought of instead piping the high pressure air from the bottom of the windshield area to beh8nd the tires to decrease the vortex?
Porsche made some wheels at one point that were sort of fan blade spokes cooling the brakes and possibly affecting this airflow.
That's just laminar flow waiting to be used. I'm thinking, a guide vane to the tire to power up that vortex. Since it's a downwashing vortex, I can use a guide vane next to it and I'll get clean laminar downwash, and then I can direct that away from the car. What that will do is create a seal for the splitter, effectively separating the wheel wake from the splitter. Furthermore, since the vortex is down and outwashing it will also help entrain more air upstream since it will help lower the pressure at the splitter.
I want the vortex, I already made prototypes that gained me more traction on the exit of slow corners, and if I nail it, I know it'll help. I'm running .3 degrees of toe out at the front and .3 in the rear. No abnormal tire wear or heating, but more rotation and more traction in low speed. The vanes are at ~25 degrees, but the prototypes I made didn't align well with the front wheels, nor the rear wheels under cornering. If I improve the design there's a lot of potential.
Ok, I was picturing an excessive level of toe trying to achieve one goal but in the process losing the war. You will likely have slightly degraded handling and stability under hard braking, especially while cornering, depending on the flex of suspension components and bushings. Some of this can be recovered with reinforcements and harder high durometer bushings. Interesting concept, likely something that will end up on an f1 car one day if you prove it out. Standard skid pad g readings would be fine. Could be unpredictable though due to crosswind or another car nearby. This could cause loss of control if you were in the zone of using every bit of that newfound traction. Be neat to see pics if you have any posted, fair enough if you don’t want to though.
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