How Does the Type of Wing Affect a
Dragster’s Performance?
By Joey Dille
1/31/06
Preliminary
ProblemWhat type of wing can make a Top
Fuel Dragster go the fastest?
HypothesisIf a dragster has an inverted airfoil spoiler with
endplates, then it has the potential to go faster.
Independent Variable- Type of spoiler, Angle of attack
Constant Factors- Car body, Wind tunnel, Materials
Control- Car with no spoiler (Car A)
Dependent Variable- Amount of downforce and drag produced, in grams
Number of Trials- No spoiler, Flat plate spoiler(4 angles of attack),
Inverted airfoil spoiler(4 angles of attack), Inverted airfoil spoiler with
endplates(4 angles of attack). 3 wind speeds per configuration. 36 total
ProcedureI.Research
1.Aerodynamics
2.Spoilers
III.Set up measurement devices (scales)
1.Downforce-scale
2.Drag-scale with bell crank
3.Measurements in grams and -grams
IV.Make model car and wings out of wood
3.Physics of a dragster
1.Pine for car, Balsa for wings
4.How to build a wind tunnel
2.About a foot long
5.How to build a dragster
3.Plastic wheels
4.Platform for spoiler
6.How to make wings
II.Make a wind tunnel
1.Out of plywood
5.Holes for angle of attack
6.Realistic
V.Run Tests
2.Use two 3-speed fans for wind production
1.Four angles of attack per wing, 3 speeds for each
angle of attack per test procedure
3.Square shaped
2.Control-car without any wing
4.Plexiglas window
5.Braces for added strength
6.Other features added from research
VI.Collect data
VII.Analyze and organize data
VIII.Form conclusion
IX.Communicate results
Test1. ProcedureReceive instruction on use of wind tunnel from supervisor Mr. Evan of Strayer M.S.
2.
Set up table to document results in computation book.
3.
Open viewing window.
4.
Mount wing at desired angle of attack.
5.
Put model into tunnel. Make sure car is level.
6.
Close viewing window.
7.
Zero drag and lift sensors.
8.
Crank fan speed up to 20mph.
9.
Wait for readings to stabilize then document readings.
10. Crank fan speed up to 30mph.
11. Wait for readings to stabilize then document readings.
12. Crank fan speed up to 45mph.
13. Wait for readings to stabilize then document readings.
14. Turn off fan.
15. Open viewing window.
16. Remove model.
17. Repeat from step 3 until all wings and angles of attack are tested.
What is a dragster?
A dragster is a car designed specifically to travel as fast as it can in a straight
line.
The NHRA, or National Hot Rod Association, creates several “classes” of cars.
Top Fuel dragsters are the fastest class of cars.
The areas of any wings behind the front axels can be no more than 1500
in2 (.97 meters2)
The weight at the end of the run, including the driver, has to be at least
2,225 lbs (1009.24 kgs)
This is a Top Fuel Dragster
What is a wing?
A wing is a fancy name for a spoiler.
Wings are added to cars to create downforce, or negative lift.
On a car, this downforce helps the tires stick to the ground.
What is a wind tunnel?
A wind tunnel is a device used to test vehicles like planes and cars for certain
variables without actually driving or flying them.
Often, a scale model is used to show a car’s statistics at a certain speed.
My dragster will be a model of a real one and will show the force of different
wing designs.
My wind tunnel
My wind tunnel
These are pictures of my wind tunnel
Data Collecting at Strayer Middle School’s
Wind Tunnel-1/12/06
My wind tunnel did not work,
so I ended up testing here.
Force Balance on Dragster
Downforce
Drag
Traction
Ground Force
Gravity+Weight
This diagram shows how various
forces affect a dragster.
Assumptions
Prior to experimentation, several things must be
assumed in order to keep things simple and on task
1. Simple model
2. No rolling friction
3. Assume constant acceleration
4. Traction limits acceleration
How my equations work
Using the force balance and other
information from my research, I determined
an equation that will determine the projected
acceleration of my car.
a=µgc+(µCl-Cd)(AρV2)/(2m)
From my lift and drag measurements, I
determine the coefficients of lift and drag (Cl
and Cd)
When all the variables are filled in, you get
your acceleration.
My Raw Data
W ing Angle of Attack Speed (mph) Lift (-g) Drag (g) W ing
0
20
0
7
0
30
0
12
0
45
2
35
1
5
20
1
11
1
5
30
2
19
1
5
45
5
55
1
15
20
2
13
1
15
30
3
22
1
15
45
10
59
1
25
20
3
14
1
25
30
5
22
1
25
45
15
61
1
35
20
3
14
1
35
30
5
22
1
35
45
16
63
2
5
20
8
12
2
5
30
13
20
2
5
45
37
53
2
15
20
10
15
2
15
30
16
23
2
15
45
43
63
2
25
20
9
17
2
25
30
15
27
2
25
45
44
74
2
35
20
9
19
2
35
30
15
31
2
35
45
42
83
3
5
20
7
13
3
5
30
13
23
3
5
45
36
58
3
15
20
9
15
3
15
30
15
25
3
15
45
44
68
3
25
20
10
18
3
25
30
16
19
3
25
45
46
79
3
35
20
10
20
3
35
30
16
32
3
35
45
44
86
4
5
20
9
14
4
5
30
15
24
Lift (-N)
W ing Drag (N)
Speed in mps W ing Area (m2)
0
0
8.94
0
0
0
13.41
0
0
0
20.12
0
0.00981
0.03924
8.94
0.00268084
0.01962
0.06867
13.41
0.00268084
0.02943
0.1962
20.12
0.00268084
0.01962
0.05886
8.94
0.00268084
0.02943
0.0981
13.41
0.00268084
0.07848
0.23544
20.12
0.00268084
0.02943
0.06867
8.94
0.00268084
0.04905
0.0981
13.41
0.00268084
0.12753
0.25506
20.12
0.00268084
0.02943
0.06867
8.94
0.00268084
0.04905
0.0981
13.41
0.00268084
0.13734
0.27468
20.12
0.00268084
0.07848
0.04905
8.94
0.005003098
0.12753
0.07848
13.41
0.005003098
0.34335
0.17658
20.12
0.005003098
0.0981
0.07848
8.94
0.005003098
0.15696
0.10791
13.41
0.005003098
0.40221
0.27468
20.12
0.005003098
0.08829
0.0981
8.94
0.005003098
0.14715
0.14715
13.41
0.005003098
0.41202
0.38259
20.12
0.005003098
0.08829
0.11772
8.94
0.005003098
0.14715
0.18639
13.41
0.005003098
0.3924
0.47088
20.12
0.005003098
0.06867
0.05886
8.94
0.004987608
0.12753
0.10791
13.41
0.004987608
0.33354
0.22563
20.12
0.004987608
0.08829
0.07848
8.94
0.004987608
0.14715
0.12753
13.41
0.004987608
0.41202
0.32373
20.12
0.004987608
0.0981
0.10791
8.94
0.004987608
0.15696
0.06867
13.41
0.004987608
0.43164
0.43164
20.12
0.004987608
0.0981
0.12753
8.94
0.004987608
0.15696
0.1962
13.41
0.004987608
0.41202
0.50031
20.12
0.004987608
0.08829
0.06867
8.94
0.004827551
0.14715
0.11772
13.41
0.004827551
Position
Results
of My
Model
This data
shows the
physics of
a
dragster.
Distance (m)
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
0
4.02336
8.04672
12.07008
16.09344
20.1168
24.14016
28.16352
32.18688
36.21024
40.2336
44.25696
48.28032
52.30368
56.32704
60.3504
64.37376
68.39712
72.42048
76.44384
80.4672
84.49056
88.51392
92.53728
96.56064
100.584
104.60736
108.63072
112.65408
116.67744
120.7008
124.72416
128.74752
132.77088
136.79424
140.8176
144.84096
148.86432
152.88768
156.91104
160.9344
Time (s)
0
0.506291
0.209712
0.161046
0.13588
0.119812
0.108409
0.099775
0.092946
0.087369
0.082705
0.078728
0.075286
0.072269
0.069597
0.067208
0.065057
0.063106
0.061326
0.059694
0.058191
0.0568
0.055509
0.054306
0.053181
0.052127
0.051137
0.050204
0.049323
0.048489
0.047699
0.046949
0.046236
0.045556
0.044908
0.044288
0.043696
0.043128
0.042584
0.042061
0.041559
Speed (m/s)
0
15.89347773
22.45484704
27.47680438
31.69990178
35.41122493
38.75813544
41.82824896
44.67870184
47.349216
49.86873822
52.25914037
54.5374298
56.71714364
58.8092676
60.82286363
62.76551186
64.64362999
66.46270912
68.22749141
69.94210616
71.61017563
73.23489846
74.81911618
76.36536688
77.87592892
79.35285683
80.79801111
82.21308304
83.59961562
84.95902124
86.29259674
87.60153629
88.88694254
90.14983615
91.39116418
92.61180735
93.81258641
94.99426775
96.15756837
97.30316023
Acceleration (m/s 2) Elapsed Time (s) Distance (m)
31.392
0
0
31.28745344
0.506290702
4.02336
31.18331461
0.716003178
8.04672
31.0795329
0.877049475
12.07008
30.97610118
1.012929811
16.09344
30.87301626
1.13274228
20.1168
30.77027604
1.241151205
24.14016
30.66787887
1.340926505
28.16352
30.5658233
1.433872382
32.18688
30.46410798
1.521241668
36.21024
30.36273166
1.60394628
40.2336
30.26169311
1.682674444
44.25696
30.16099112
1.757960696
48.28032
30.06062452
1.83023
52.30368
29.96059215
1.899826823
56.32704
29.86089287
1.967034974
60.3504
29.76152553
2.032091577
64.37376
29.66248901
2.09519715
68.39712
29.5637822
2.15652306
72.42048
29.46540397
2.216217123
76.44384
29.36735323
2.2744079
80.4672
29.26962886
2.33120803
84.49056
29.17222978
2.386716859
88.51392
29.07515489
2.441022537
92.53728
28.97840311
2.494203706
96.56064
28.88197335
2.546330872
100.584
28.78586453
2.597467541 104.60736
28.69007559
2.647671149 108.63072
28.59460546
2.696993847 112.65408
28.49945307
2.745483154 116.67744
28.40461735
2.793182512
120.7008
28.31009726
2.840131762 124.72416
28.21589173
2.886367547 128.74752
28.12199972
2.931923656 132.77088
28.02842019
2.976831331 136.79424
27.93515209
3.021119522
140.8176
27.84219438
3.06481512 144.84096
27.74954603
3.107943152 148.86432
27.657206
3.15052696 152.88768
27.56517328
3.192588353 156.91104
27.47344683
3.234147746
160.9344
NACA
Airfoil
This is a graph of the effect of angle of attack with a NACA airfoil
Effect of Angle of Attack on Elapsed Time
(NACA 2412 Airfoil)
6
Elapsed Time (seconds)
5
4
3
E.T.
2
1
0
0
5
10
15
Angle of Attack (Degrees)
20
25
Graph
This is my graph of how the angle of attack of my wings affects
the time at the end of the run, or elapsed time.
Effect of Wing on E.T.
5.260
1/4 Mile Elapsed Time (seconds)
5.240
5.220
5.200
None
5.180
Wing 1
5.160
Wing 2
Wing 3
5.140
Wing 4
5.120
5.100
5.080
5.060
0
5
10
15
20
25
Angle Of Attack (Degrees)
30
35
40
Conclusions
First of all, my hypothesis was disproved. I
hypothesized that the inverted airfoil spoiler with
endplates would have the lowest elapsed time. It
was really the flat plate spoiler at 15°.
I think this was because the endplates produce
more lift, but end up causing too much drag.
Possible sources of error for my experiment could
have been that the speeds from the wind tunnel
were not exact. Another thing was that I am not
the best woodworker, so my wings could have
been slightly off.
Possible applications for my experiment would be
at a real drag race.