Wind Tunnel Analysis of Flying Disc Aerodynamics

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Wind Tunnel Analysis of Flying Disc
Aerodynamics Union Scholars Sophomore Project by
Patrick Allen Advised by Professor
Anderson Winter, Spring 2004
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Yearly, there are more frisbees sold in the
United States than baseballs, basketballs and
footballs, combined.
The modern shaped, conventional Frisbee evolved
in the late 1940s, but its origin is commonly
traced to the Frisbie Pie company in the 1920s.
Frisbie
Frisbee
Source http//www.recess.ufl.edu/transcripts/2002
/0111.shtml
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Frisbees have become specialized sports equipment.
Disc Golf19751 -approximately 8.5 inches in
diameter -approximately .5 inch rim
depth -optimized for various specific
characteristics long range, right curving, left
curving
Ultimate Frisbee19682 -approximately 10 inches
in diameter -approximately .75 inch rim
depth -optimized for short to mid range handling
1. http//www.discgolfassoc.com/history.html 2.
http//www.whatisultimate.com/history/history_game
1_en.html
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http//www.pbase.com/elsinger/flwrbst
Frisbeea dangerous obsession?
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Project objectives
I. Document the lift and drag characteristics of
Ultimate and golf disc types
-Lift/drag dynamometer
II. Examine the flow field over statically
mounted discs
-Particle Image Velocimetry system
III. Examine the flow field over rotating discs
-Motorized rotation
-Particle Image Velocimetry system
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I. Lift and Drag Background
What is known about Frisbee flight already?

• Frisbees are essentially airfoilswings

Source http//www.disc-wing.com/index.htm
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I. Lift and Drag Background
What is known about Frisbee flight already?

• Frisbees are essentially airfoilswings

-Surface flow visualization methods
Source http//www.disc-wing.com/index.htm
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II. Static Flow Background
-Surface pressure tappings using pressure
transducer
-Kerosene-fluorescent powder methodtime averaged
surface flow
Source http//www.disc-wing.com/index.htm
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III. Rotational Flow Background
-Center of pressure vs. center of gravity

• Rotation is necessary for stability in flight,
  thanks to gyroscopic effects

Picture source http//www.disc-wing.com/index.htm
-leads to rolling moment
-the importance of mass distribution the
Discraft Ultrastar 175
-does rotation lead to additional lift force?
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III. Rotational Flow Background
Rotation has been investigated before, most
notably by Potts and Crowther of the University
of Manchester
Their conclusion rotation has a negligible
effect on the lift generated by a flying disc
However, Lazzara of Brown University suggest that
rotation is responsible for a small component of
lift
-Advance Ratio (rim speed)/(flow speed)
-Does Potts conclusion hold true for AdvRgtgt1?
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Project objectives
I. Document the lift and drag characteristics of
Ultimate and golf disc types
-Lift/drag dynamometer
II. Examine the flow field over statically
mounted discs
-Particle Image Velocimetry system
III. Examine the flow field over rotating discs
-Motorized rotation
-Particle Image Velocimetry system
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I. Lift and Drag Analysis
-The wind tunnel lab
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I. Lift and Drag Analysis
-Dynamometer and golf disc installed in test
section
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I. Lift and Drag Analysis
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I. Lift and Drag Analysis
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II. Static Flow Visualization
Surface flow visualization to
direct flow field visualization
Particle Image Velocimetry PIV
-High resolution digital camera
-Planar laser strobe
-Really powerful computer
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III. Rotational Flow Visualization
-In manufacturing motorized rotation system
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Acknowledgements
-Professor Anderson -Stan Gorski -Jim Howard
and Roland Pierson -Internal Education Fund
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Wind Tunnel Analysis of Frisbee
Aerodynamics Scholars Sophomore Project by
Patrick Allen Advised by Professor Anderson
Picture source http//www.disc-wing.com/index.htm