So the test results are in...
OCCFD wrote:
The drag and downforce performance predicted by the simulation are:
Total drag: 1177.57 N
Drag coefficient - Cd: 0.59
Drag area - Cd.A: 0.98 m2
Total Downforce: -4309.58 N
Downforce coefficient - Cl: -2.16
Downforce area - Cl.A: -3.59 m2
CoP of downforce: 1.850 m along streamwise (Y) direction from Y = 0.00 m.
KVRC Only: Corrected CoP of downforce: 1.750 m along streamwise (Y) direction from Y = 0.00 m.
The pressure at intake and exhaust are:
Engine intake, Area: 0.016m2 - Compliant
Surface integral of pressure: 3.42 Pa.m2
Engine exhaust, Area: 0.010m2 - Compliant
Surface integral of pressure: 0.90 Pa.m2
Cooling intake, Area: 0.121m2 - Compliant
Cooling exhaust, Area: 0.081m2 - Compliant
Differential of surface integral of pressure: 17.44 Pa.m2
I'm reasonably pleased with the figures: no surprise that it has relatively low Cl.A as that is exactly the set-up that I was going for in the test race: now I have good basis and understanding for the air flows around the car.
The first plan of action has to be getting the cooling air flow sorted: at present there is insufficient pressure at the cooling inlet and the car therefore won't be able to make full power....
The tricky part now is trying to get more flow to the radiators, without (hopefully) reducing front-end downforce (in fact, I need
more front downforce to balance the car).
The sketch below shows how air entering the front of the car (1) travels through and around the car:-
- Some travels over the sidepod (2)
- Some travels around the side of the sidepod(3)
- some travels under the floor (4)
- the remainder goes through the cooling system
In Class B we cannot simply increase the sidepod opening size as the inlet is a fixed ("Spec") part. My original plan had been to adjust the barge boards to direct less air around the sides of the car (3) and (hopefully) more through the cooling (5)... I suspect however that this would more than likely just reduce the amount of flow going through the car in the first place (1)... so I intend to change the design slightly at the front to encourage more air through the suspension (1) rather than over the top
and to adjust the barge board (3)....
...The problem now is that because I'm not doing my own CFD I also need to sort out a high downforce package for the first official round....
....More images coming soon.....