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Aerodynamics. Forces in a Climb. Examples of Aerodynamics. What if? Drag > Thrust Lift > Weight Thrust > Drag Weight > Lift. Airplane vs. Rocket. Why have both? Different Environments Airplanes are used within the atmosphere. Rockets can operate in the vacuum of space .
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Aerodynamics UA Summer Engineering Program 2012
Forces in a Climb UA Summer Engineering Program 2012
Examples of Aerodynamics • What if? • Drag > Thrust • Lift > Weight • Thrust > Drag • Weight > Lift UA Summer Engineering Program 2012
Airplane vs. Rocket • Why have both? • Different Environments • Airplanes are used within the atmosphere. • Rockets can operate in the vacuum of space. • What’s the difference in operation? • THRUST! UA Summer Engineering Program 2012
Rockets • Chinese usedfirearrows: arrows propelled by gunpowder • First solid propellant rockets • Modern rocketry in Russia via 1898 with liquid propellants • Benchmark: Wright Brothers’ airplane first flight (1903) • V-2 Rocket used as a during WWII • Rockets in Space: Sputnik in1957 and then Explorer I UA Summer Engineering Program 2012
Rocket Motion & Thrust • As opposed to an airplane, the thrust counteracts the weight and propels the rocket on its flight patch. • The lift is used to stabilize the rocket. • The thrust is determined by the rocket’s engine: • Engine expels some gas or liquid into the air, applying a force on the air. • By Newton’s 3rd law of motion, an opposite force is applied to the rocket. UA Summer Engineering Program 2012
Rocket Structure Most important system that is vital to rocket UA Summer Engineering Program 2012
Propulsion • The propulsion system is responsible for the thrust of the rocket. • Different types of engines depend on the fuel & oxidizer used for combustion: • Solid Propellant • Missiles • Model Rockets • Boosters for satellite launchers • Liquid Propellant • Engines of Space Shuttle • Missiles into orbit • Hybrid • Both liquid & solid Saturn 1B UA Summer Engineering Program 2012
Propulsion • Hybrid Engine Set-up: IT’S All ABOUT THE NOZZLE. UA Summer Engineering Program 2012
Staging • Problem: What happens when you run out of fuel? • Problem: For large rockets, weight becomes a serious issue to achieve necessary distance or velocity. UA Summer Engineering Program 2012
Staging: Use Several Engines! 2 Types of Staging: • Serial Staging • Larger rocket used for powered ascent. Smaller rocket used for upper stage. • Saturn V • Parallel Staging • Smaller first stage engines surround other operating engines. Larger engines used to sustain flight. • Space Shuttle Discovery UA Summer Engineering Program 2012
Rocket Rotation • It is important to know the orientation of the rocket in a 3-D system: • Roll: affects stability of flight • caused by deflection in fins or gimbal the rocket engine • Pitch: deflection in the nozzle, • Thrust changes direction • Yaw: changes lateral direction of the rocket • Thrust changes direction UA Summer Engineering Program 2012
Rocket Equations of Motion • To build equations of motion, remember the following: • The rotation of the rocket is around the CG. • Lift and drag are applied on the CP. • Thrust and weight are applied on the CG. • Newton’s 2nd law: F = m a. UA Summer Engineering Program 2012
Rocket Modeler Equations UA Summer Engineering Program 2012
Simplified Rocket Modeler Equations UA Summer Engineering Program 2012
Rocket Flight • Effects on rocket flight are based on the rocket construction, the velocity of the rocket and its environment. • The rocket’s shape,material, and size affect its weight, its coefficient of lift and drag. • Therelative velocityof the rocket affects its lift and drag. • Thelocation affects the force due to gravity on the rocket. If the rocket is moving through air, the density of the air and the viscosity will affect the lift and drag. UA Summer Engineering Program 2012
References • Rocket Thrust: • http://www.grc.nasa.gov/WWW/K-12/rocket/rktth1.html • Rocket Aerodynamics • http://www.grc.nasa.gov/WWW/K-12/rocket/rktaero.html • Rocket orientation • http://www.swe.org/iac/lp/airspace_04.html • http://i.zdnet.com/blogs/boeing-s3g1h_n2-logo.jpg • http://www.grc.nasa.gov/WWW/K-12/rocket/rockpart.html • Airplane forces in a climb: • http://www.grc.nasa.gov/WWW/K-12/BGP/Sheila/climbvectors_act.htm • Flight Equations: • http://www.grc.nasa.gov/WWW/K-12/rocket/flteqs.html • http://www.grc.nasa.gov/WWW/K-12/rocket/ballflght.html UA Summer Engineering Program 2012