This is going to be long thread with lots of the information that I've got for further reading.
I. Resources
"Frisbee Flight Simulation and Throw Biomechanics "
Masters Thesis by By Sarah Ann Hummel
This is the most technical with many equations and advanced math involved.
"Identification of Frisbee Aerodynamic Coefficients using Flight Data"
by Hummel, Sarah and M. Hubbard, 4th International Conference on the Engineering of Sport, Kyoto,
Japan, September 2002.
"Frisbee Physics: How does physics play a role in Frisbee flying?"
Simple Aerodynamics of a frisbee- in layman's terms
"The Physics of Disc Flight"
"The Flight Of The Frisbee" excerpt
By Louis A. Bloomfield
$7.95 for the Scientific American article
Book-
Spinning Flight: Dynamics of Frisbees, Boomerangs, Samaras and Skipping Stones, by Lorenz, Ralph; Copernicus, New York (September 2006);
ISBN 978-0-387-30779-4
Synopsis
II. "The Flight Of The Frisbee" By Louis A. Bloomfield
by Louis A. Bloomfield
Professor of Physics, University of Virginia
Author of
How Things Work: The Physics of Everyday Life
Modern Frisbees don't look much like tins from Bridgeport, Conn.'s, Frisbie Pie Company—the decades-old platters behind the name. But they fly through the air for the same reasons. Both are essentially spinning wings that stay aloft thanks to
aerodynamic lift and
gyroscopic stability.
Forward flight splits rushing air at the disk's leading edge: half goes over the Frisbee; half goes under. Because that edge is tipped up, the disk deflects the lower airstream downward. As the Frisbee pushes down on the air, the air pushes upward on the Frisbee--a force known as
Aerodynamic lift. The upper airstream is also deflected downward. Like all viscous fluids, flowing air tends to follow curving surfaces--even when those surfaces bend away from the airstream. The inward bend of the upper
airstream is accompanied by a substantial drop in air pressure just above the Frisbee, sucking it upward.
Limits to the airstream's ability to follow a surface explain why a Frisbee flies so poorly upside down. When the upper airstream tries to follow the sharp curve of an inverted Frisbee's hand grip, its inertia breaks it away from the surface. A swirling air pocket forms behind the Frisbee and destroys the suction, raising the air resistance. Once this air resistance has sapped the inverted disk's forward momentum, it drops like a rock. Players can take advantage of this effect in a hard-to-catch throw called the hammer.
Rotation is crucial. Without it, even an upright Frisbee would flutter and tumble like a falling leaf, because the aerodynamic forces aren't perfectly centered. Indeed, the lift is often slightly stronger on the forward half of the Frisbee, and so that half usually rises, causing the Frisbee to flip over. A spinning Frisbee, though, can maintain its orientation for a long time because it has
angular momentum, which dramatically changes the way it responds to aerodynamic twists, or torques. The careful design of the
Frisbee places its lift almost perfectly at its center. The disk is thicker at its edges, maximizing its angular momentum when it spins. And the tiny ridges on the Frisbee's top surface introduce microscopic turbulence into the layer of air just above the label. Oddly enough, this turbulence helps to keep the upper airstream attached to the Frisbee, thereby allowing it to travel farther.
Bernoulli Effect
The higher the speed of a fluid, the lower the pressure. So increasing fluid speed decreases pressure and decreasing fluid speed increases pressure. With airplane wings the air over the top of the wing has to go farther because of the curved shape, so the speed of the air on top is greater than the speed of the air below. Therefore, on the top the pressure drops so that the air can speed up. So the pressure below is greater than the pressure on top, which results in an upward force of lift. In summary, anything that increases air speed increases lift. (Lift increases with the square of the air speed.)
III. Definitions
·Boundary layer- the thin layer of air next to the surface of the disc. Boundary layers are laminar at the front and turbulent at the rear.
·Drag- any disturbance in the airflow increases drag.
·Gyroscopic inertia- the ability of a spinning axle of a gyroscope to always point in the same direction.
·Gyroscopic precession- the tendency of a gyroscope to move at right angles to the direction of any force applied against it.
·Nutation- oscillatory movement of the axis of a rotating body; wobble
·Precession- a comparatively slow gyration of the rotation axis of a spinning body about another line intersecting it so as to describe a cone caused by the application of a torque tending to change the direction of the rotation axis.
-OR the ability of a spinning axle of a gyroscope always to point in the same direction.
·Parallel flow- orderly wind paths parallel to the surface
·Profile drag - drag from shape and skin friction
·Skin friction – friction at the surface between the disc and the boundary layer. Skin friction is lowered by delaying the change in air flow, from laminar at the front to turbulent at the back, as long as possible.
·Stall- when lift stops.
·Turbulent flow- irregular air flow
IV. Forces on a flying disc:
Aerodynamic drag
Gyroscopic stability
Static stability?
Dynamic stability
Tractability
Bernoulli Effect
Air Friction
Laminar air flow
Turbulent air flow
