Applications of Aerodynamics In Sport Introduction: Many Activities are incluenced by Aerodynamics Aerodynamics is the study of Fluid forces relating to the Air In determining the Drag and Lift forces, Velocity was the critical component Expect that faster activities are more susceptible to Aerodynamic Influence Cycling, Skiing, Skating, etc. as opposed to walking, dancing, etc. Other times, the amount of the force can be considered negligable Weight Lifting as opposed to Volleyball, Badminton, Baseball Chapter is broken down into two sections: Effects of Drag Effects of Lift And then a special type of lift caused by spin (Magnus Effect) Effects of Drag on the Body and Objects Drag is a force that always acts opposite to relative motion If motion is in line with gravity Drag opposes gravity Person/object reaches Terminal Velocity when are equal Drop bowling ball and feather from Empire State building Bowling ball hits first as has less Drag Drop them in a Vacuum Cylinder Both reach ground at the same time (no drag) Objects frequently do not reach Terminal Velocity Not enough flight time Sometimes, goal is to maximize drag force Parachuting Is done by maximizing surface area on leading edge spread eagled Most times, goal is to minimize drag force - streamlining Floater serve in Volleyball Ball has no spin Hits pockets of different air pressure Is moved in irregular path Same as Knuckleball Pitch in Baseball Golf Ball is interesting Case Dimples on ball increase the Surface Drag However, they DECREASE Total drag as Profile Drag Decreases Dimples cause boundary layer turbulence early Somehow, causes seperation further at the back Results in Decreased turbulence * Read about Long Jump, etc. * Effects of Lift Force Variables affecting Lift Force Review from equation (Surface Area, Fluid Density, Velocity, etc.) Other variables change throughout the flight of the object Angle of Projection Line of Flight Attitude Angle Center of Pressure Angle of Projection Angle Velocity (through CG) makes with ground Attitude Angle Angle formed between "main" plane of object and ground Represents the orientation of the object Angle of Attack (at release) Angle between main plane and velocity vector Center of Pressure (Theoretical) Point at which lift and drag act Line of Flight Path followed by the CG Depends upon all the above (plus the Fluid Forces) * Read about the Discus and the Javelin, and Ski Jumping * Magnus effect: Lift Force Rotation of object changes pressure of fluid surrounding it Faster area = Lower pressure Ball Moves because of Pressure Differential * Golf Ball, Curve Ball *