This page lists the results of performing wind tunnel tests of 4 quater scale models of different car designs at the UWE wind tunnel on 2006-12-08.
Ground Plane alone (To be taken way from all other readings)
|
Velocity m/s |
L (N) |
D (N) |
S (N) |
|
15.0 |
0.24 |
2.22 |
0.53 |
|
25.0 |
-0.03 |
5.6 |
1.55 |
|
DragCoeficient |
|
Car 1: Original body, no canopy, steering king-pins.
|
Velocity m/s |
L (N) |
D (N) |
S (N) |
|
15.0 |
-0.73 |
4.03 |
0.92 |
|
24.9 |
-2.2 |
10.6 |
2.47 |
|
Area |
|
||
|
DragCoeficient |
|
Car 1: Original body, no canopy, no steering king-pins.
|
Velocity m/s |
L (N) |
D (N) |
S (N) |
|
15.0 |
-0.68 |
3.77 |
0.94 |
|
25.0 |
-2.41 |
9.97 |
2.50 |
|
Area |
|
||
|
DragCoeficient |
|
Car 1: Original body, no canopy, no steering king-pins, wheels spaced out double the distance (8inches).
|
Velocity m/s |
L (N) |
D (N) |
S (N) |
|
15.0 |
-0.50 |
3.74 |
1.04 |
|
25.0 |
-2.10 |
9.92 |
3.07 |
|
Area |
|
||
|
DragCoeficient |
|
Car 1: Original body, with canopy, no steering king-pins.
|
Velocity m/s |
L (N) |
D (N) |
S (N) |
|
15.0 |
-1.17 |
4.03 |
0.97 |
|
25.0 |
-3.55 |
10.75 |
2.48 |
|
Area |
|
||
|
DragCoeficient |
|
Car 1: Original body, with longer canopy, no steering king-pins.
|
Velocity m/s |
L (N) |
D (N) |
S (N) |
|
15.0 |
-0.09 ? |
3.92 |
0.9 |
|
25.0 |
-2.2 |
10.20 |
2.63 |
|
Area |
|
||
|
DragCoeficient |
|
Car 2: No canopy
|
Velocity m/s |
L (N) |
D (N) |
S (N) |
|
15.0 |
-7.85 |
3.33 |
0.75 |
|
25.0 |
-9.3 |
8.8 |
2.32 |
|
Area |
|
||
|
DragCoeficient |
|
Car 3: Gareths car
|
Velocity m/s |
L (N) |
D (N) |
S (N) |
|
15.0 |
-7.16 |
3.33 |
0.76 |
|
25.0 |
-8.90 |
8.75 |
1.75 |
|
Area |
0.0171 m square |
||
|
DragCoeficient |
0.50 ? |
Car 4: Rounded and tapered front, with canopy
|
Velocity m/s |
L (N) |
D (N) |
S (N) |
|
15.0 |
-6.11 |
3.44 |
1.1 |
|
25.0 |
-7.08 |
9.04 |
2.97 |
|
Area |
0.0193 m square |
||
|
DragCoeficient |
0.49 ? |
Car 4: Rounded and tapered front, with slotted canopy
|
Velocity m/s |
L (N) |
D (N) |
S (N) |
|
15.0 |
-6.9 |
3.38 |
0.48 |
|
25.0 |
-8.24 |
8.91 |
1.31 |
|
Area |
0.0193 m square |
||
|
DragCoeficient |
0.47 ? |
Car 4's air drag was: 3.3N. Car 1's air drag was: 4.37N. This is a 32% improvement. The kingpins made about a 15% difference on the old car. Car 4 has a larger gap between the front wheel and body and so the kingpins will probably make less difference on this car, but we can probably improve on the 32% by doing something with the kingpins.
It would have been good to have been able to test the following in the wind tunnel: