LVDH wrote: ↑31 Oct 2017, 16:10
variante wrote: ↑30 Oct 2017, 17:30
My diffuser works the opposite way: less air coming from the front improves its performace. So having the biggest front diffuser/wing is the way to go for my layout. Airflow comes almost exclusively from the sides of the car.
It's a well developed solution, and I know other people adopt it... you might want to explore it
Without really knowing it for sure I think the choice between a floor that draws air from the front (and profits from the sides sealed) and one which gets the air from the sides is a question of how much resistance the air sees traveling through the floor and how good the diffuser sucks air through this bottleneck. Usually in aerodynamics it is good to derive some dimensionless number. I just came up with this:
Diff_factor=((V*h^2)/(l*nu))*((e-e_id)/e_id)^2
With:
- e - expansion factor diffuser
- e_id - ideal expansion factor
The idea is that more air velocity and a higher floor help to get air through the floor and a longer length and higher viscosity make it harder. The part with the expansion factors is about how well the floor is designed. The closer you are at the ideal expansion the more you will force through the floor.
I assume that if the Diff_factor is above a certain number, you go for an F1 style diffuser which draws air from the front and below a certain factor you have to get the air from the sides.
The question is why you cannot do both.
Given certain boundary conditions, one way is superior to the other. And you may find out that the trade off is in great favor towards the former. While you are forced to deal with both, you do work to make the former prevail over the latter as much as possible.
Practically, I would be happy to see all of the airflow that is fed to the diffuser coming from the sides of the car. The reason is simple: air coming from the sides didn't experience an expansion like air that went through a front wing, so it is faster; also, it already comes at a good angle to shed vortices, thus I can use a diffuser with higher expansion ratio.
What I think you forgot in your equation (even though it is indirecly included) is to take into account the front wing. Feeding the diffuser with air coming from the sides lets you run a front wing which is as aggressive as you like, without affecting the undertray... resulting in a total downforce gain
Ft5fTL wrote: ↑31 Oct 2017, 17:06
This will be my last submission for this years competition. I'm using the same car for the last race aswell. I will serve my mandatory military service starting tommorrow. It will end around april 18th (i hope i will be here for the next years competition). So take care everyone.
See you soon
Take care!
BTW a pity not to see TF racing this time...
