450 kph F1

[Andres125sx]

Anycase 450kph is just an arbitrary number...

But breaking the 400kph barrier for a competition wich race on twisty tracks might be doable and would send F1 directly to the "no other competition can dare to compare with F1" level again.

[hollus]

A possible point to consider: At 450 km/h, the top parts of the tires are moving forward at 900 km/h. Considering the very open wheels of a F1 car, would there be an incipient sonic shock at that speed contributing disproportionately high drag above the standard "drag increases with the square of the speed"?
Note to self: When we say that F1 cars move mostly below mach 0.3 and thus the assumption of incompressible flow is good enough for CFD, that does not include the top parts of the tires.
So what would happen just by including covered wheels in the current formula? Would that allow for 400km/h top speeds in the current twisty layouts?
A while ago I made a very simple, basic model of a 2015 spec F1 car for Optimum Lap. If someone can come with a reasonable estimate of the (increase?) in downforce coefficient and the decrease in the drag coefficient of a F1 car by adding covered wheels, I could plug them in that model and see what happens.

[FW17]

Can you pls explain your 900kph wheel tip assumption?

The speed of the wheel will be only 250kph considering the diameter

[rscsr]

Can you pls explain your 900kph wheel tip assumption?

The speed of the wheel will be only 250kph considering the diameter

when it is assumed, that the tyre has no slip on the track and the car travels at 450kph you double the speed on the top surface.
This is because the contact point acts as the instant center of the rotation, the centre of the tyre moves at 450kph and the top has double the distance to the instant center of rotation. You can imagine it as an addition of an unrotating tyre moving at 450kph and a rotation, so that the contact point with the surface has no speed.

The wheel centre always moves at the same speed as the rest of car, therefore 450kph.

[hollus]

Another way to look at it: The average of the wheel moves at 450 km/h. Since the contact patch does not move (0 km/h, the top must deviate in the opposite direction and magnitide: 900 km/h.
0 km/h at the contact patch, 450 km/h at the wheel center -> 900 km /h at the top.
Each point in the surface of a tire is constantly changing speed between 0 and double the speed of the car (average = speed of the car).

[FW17]

A while ago I made a very simple, basic model of a 2015 spec F1 car for Optimum Lap. If someone can come with a reasonable estimate of the (increase?) in downforce coefficient and the decrease in the drag coefficient of a F1 car by adding covered wheels, I could plug them in that model and see what happens.

http://web.aeromech.usyd.edu.au//15afmc ... C00191.pdf

The spinning wheel apparently produces lift, is it wise to cover it?

[Greg Locock]

Milliken p570 based on frontal area of tire Cd 0.579 Cl 0.180 Both numbers increase with a stationary tire, so a close fitting fairing might make things worse. That's a very odd result.