Welcome to Aerospace Engineering DESIGN-CENTERED INTRODUCTION TO AEROSPACE ENGINEERING

Transcription

1 Welcome to Aerospace Engineering DESIGN-CENTERED INTRODUCTION TO AEROSPACE ENGINEERING Topics 1. Course Organization 2. Today's Dreams in Various Speed Ranges 3. Designing a Flight Vehicle: Route Map of Disciplines 4. Mission Specification & Take Off Weight 5. Force Balance during flight 6. Earth's Atmosphere 7. Aerodynamics 8. Propulsion 9.Performance, Stability & Control 10. Structures and Materials 11. High Speed Flight 12. Space Flight

2 In this course we will use the motivation of designing a specific vehicle to learn about the various areas of aerospace engineering. So we will go off into one area after another, but always come back at the end of that detour, and do some more calculations or refinement of our design oneclick oneclick _uploads/2007/08/traian_vuia_flying _machine.jpg

3 Some Common Aerospace Terms ICAO / FAA / ITU / NATO Phonetic Alphabet 1955 International Standard Atmosphere: Sea-level Standard Pressure: 101,325N/m 2 Sea-level Standard Temperature: K Gas Constant for Air: m 2 K -1 s -2 Universal Time: xxyy hours Zulu Alpha November (GMT in 24-hour format) Bravo Oscar Charlie Papa Unit of Speed: Delta Quebec 1 Nautical mile per hour = 1 Knot (1kt) = h 152 statutory Echo Romeo mile per hour Foxtrot Sierra Standard Altitudes: Golf Tango FL 020 2,000 feet ISA Hotel Uniform FL ,000 feet ISA India Victor Runway Directions Juliet Whisky degrees (slightly North of East) Kilo X-ray degrees (South) Lima Yankee degrees (North) Mike Zulu degrees (West)

4 Today's Dreams Dream Technical Requirements Fly like a bird 0 160kmph; land anywhere, cross mountains & rivers Commute by air Garage to parking lot to garage. safety & traffic management for 1 million cars, 200kmph, all-weather City-city, doorstep service 600kmph; VTOL with mild downblast and noise Cross the world in a day Visit low earth orbit Visit nearby planets Visit nearby star systems Deep space travel Nano-probes Mach 3, approximately 1800 mph + range of 10,000 miles. 24,000 kmph re-usuable spaceliner; comfortable takeoff, acceleration, re-entry and landing. < $100 /kg. 100,000 kmph; months of endurance, radiation shielding. Proxima Centauri, 6 light-years: 5.7E14 km Millions of light-years. 10E-9 meters size. Numerous applications.

5 Aerospace Design: A Route Map of Disciplines Aerospace Engineering i involves many "disciplines": i " each might warrant a separate division in a major company, with dedicated experts who spend decades specializing in it. Here we take a quick look at some of these disciplines.

6 Design of a Flight Vehicle Step Define Requirements Survey past designs Weight estimation Aerodynamics Propulsion selection Issues What must the vehicle do? Why? What has been shown to be possible? How much will it weigh, approximately, going by past experience and our projection? Wing size, speed, altitude, drag How much thrust is needed? How many engines? How heavy? Fuel consumption? Performance Configuration Fuel weight, take off distance, speed/altitude/ maneuvering boundaries How should it look? Designer s decisions needed! Stability & Control Locate & size the tail, flaps, elevators, ailerons etc. Fuel distribution. ib ti Structure Detailed engineering Strength of each part, material, weight reduction, life prediction. Design each part, see how everything fits, and plan how to build and maintain the vehicle. Life-cycle cost Iteration Flight Simulation Testing Refinement Minimize cost of owning the vehicle over its entire lifetime. Are all the assumptions satisfied? Refine the weight and the design. Describe the vehicle using mathematics. Check the "flight envelope". Measure model characteristics, verify predictions. Build & test first prototype. Reduce cost and complexity, improve performance, safety and reliability.

7 Aspect of Aerospace Engineering Basic disciplines / courses needed from the 1st 2 years of engineering school Mission Specification Weight Estimation Technology forecasting, market surveys, vehicle performance, economics, social sciences, political science Statistics, technology forecasting Aerodynamics Physics, calculus, computer science, optics, lasers, signal processing, image processing, acoustics, thermodynamics Propulsion Performance Structures Physics, thermodynamics, chemistry, lasers, optics, environmental sciences, acoustics Physics, Statics and Dynamics, calculus; flight mechanics Materials, Statics, Dynamics, Strength of Materials.

8 Layout and detail design Stability Controls Instrumentation & communications Engg. graphics, psychology, economics, ergonomics Statics, calculus Laplace transforms, differential equations, electrical engg., computer science Optics, electronics, signal processing, computing Space propulsion Electricity, it magnetism, nuclear engg., chemistry, physics, dynamics, thermodynamics Trajectories & space mission design dynamics, astronomy, modern physics Spacecraft design Flight Simulation Ground and flight testing and experimentation Lifecycle cost heat transfer, materials, photoelectricity, thermodynamics, chemistry, physics, physiology. Flight mechanics, image processing, engg. graphics, computer science, control theory. All aerospace engg. disciplines, physics, chemistry, mechanical design, electronics, signal processing, image processing, computer science. Manufacturing, Systems Engg., Optimization, Economics, Political and Legal Issues.