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Space travel and space research. Paul D. Ronney Dept. of Aerospace & Mechanical Engineering University of Southern California Los Angeles, CA 90089-1453 USA Presented at Jhong-Li High School, 3 October 2005 http://ronney.usc.edu. University of Southern California.
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Space travel and space research Paul D. Ronney Dept. of Aerospace & Mechanical Engineering University of Southern California Los Angeles, CA 90089-1453 USA Presented at Jhong-Li High School, 3 October 2005 http://ronney.usc.edu
University of Southern California • Established 125 years ago this week! • …jointly by a Catholic, a Protestant and a Jew - USC has always been a multi-ethnic, multi-cultural, coeducational university • Today: 32,000 students, 3000 faculty • 2 main campuses: University Park and Health Sciences • USC Trojans football team ranked #1 in USA last 2 years
USC Viterbi School of Engineering • Naming gift by Andrew & Erma Viterbi • Andrew Viterbi: co-founder of Qualcomm, co-inventor of CDMA • 1900 undergraduates, 3300 graduate students, 165 faculty, 30 degree options • $135 million external research funding • Distance Education Network (DEN): 900 students in 28 M.S. degree programs; 171 MS degrees awarded in 2005 • More info: http://viterbi.usc.edu
Paul Ronney • B.S. Mechanical Engineering, UC Berkeley • M.S. Aeronautics, Caltech • Ph.D. in Aeronautics & Astronautics, MIT • Postdocs: NASA Glenn, Cleveland; US Naval Research Lab, Washington DC • Assistant Professor, Princeton University • Associate/Full Professor, USC • Research interests • Microscale combustion and power generation (10/4, INER; 10/5 NCKU) • Microgravity combustion and fluid mechanics (10/4, NCU) • Turbulent combustion (10/7, NTHU) • Internal combustion engines • Ignition, flammability, extinction limits of flames (10/3, NCU) • Flame spread over solid fuel beds • Biophysics and biofilms (10/6, NCKU)
What is gravity? • 4 forces of nature • Gravity force • Electromagnetic force • Strong nuclear force • Weak nuclear force • Gravity is the attractive force between any two objects • Gravity is the most constant feature of our lives • Aristotle's "laws" of nature: heavier objects fall faster than lighter objects • Galileo Galilei proved this wrong!
Gravity on the planets and the moon Earth 1 g Moon 1/6 g Mars 1/3 g Jupiter 2.5 g Saturn 1.1 g
What happens when there is no gravity? • “Microgravity” (µg) • Simple example - candle flame • Hot gases don’t rise - flame shape and burning rate are different 1g µg
Why study microgravity? Material science Earth-grown crystal: defects in structure Space-grown crystal: nearly perfect structure
Fundamental physics Einstein predicted that space-time is warped by gravity Satellite experiment to test Einstein’s prediction more accurately than is possible on earth
How do we remove gravity? - free-fall Japan Microgravity Center - Kamisunagawa, Hokkaido Largest microgravity facility on earth
Example of microgravity research - “FLAME BALLS” • Predicted by Russian physicist Yakov B. Zeldovich in 1944, but no experimental evidence until ….
Flame balls - history • Ronney (1990): flame balls accidentally discovered in very weak hydrogen-air mixtures in drop-tower experiment
Flame balls - history • Results confirmed in aircraft flights, but aircraft vibrations problematic
Implementation of space experiment • Need space experiment - long duration, high quality µg • Structure Of Flame Balls At Low Lewis-number (SOFBALL) • 2 NASA Space Shuttle missions (April 4 - 8, 1997, July 1 - 16, 1997)
Implementation of space experiment • Combustion Module-1 (CM-1) facility • 15 different mixtures burned
Experimental apparatus • Combustion vessel • Spark ignition system • Video cameras • Temperature, pressure, heat transfer
Flame balls - practical importance • Fire safety in manned spacecraft - space shuttle and International Space Station • Flame ball - simplest possible flame - test combustion models • Improved understanding of combustion of weak mixtures - can provide better fuel efficiency & lower pollutant emission, but better scientific understanding needed
Flame balls in space • Stable for more than 500 seconds (!) • Weakest flames ever burned (1 – 2 Watts/ball) (birthday candle ≈ 50 Watts) 4.0% H2-air, 223 sec elapsed time 4.9% H2- 9.8% O2 - 85.3% CO2, 500 sec 6.6% H2- 13.2% O2 - 79.2% SF6, 500 sec
Re-flight on STS-107 / Columbia mission • SOFBALL mission re-flown on STS-107 / Columbia’s last flight to obtain additional scientific results • Much of experimental data obtained despite loss of Columbia and crew by “downlinking” data to the ground during the mission
Space flight training • 2 types of training • Orbiter-related • Launch & entry • Living in space • Photography, videography • Payload related • Science background • Procedures and schedules • Performing experiments • On-orbit repair • Not like “The Right Stuff” now - STRAIGHTFORWARD • Toughest part - TRAVEL • Best parts • Doing experiments when no one can predict what will happen • Looking out the window
Space flight training • 3 types of astronauts • Pilots • Responsible for launch, landing and on-orbit operation of Space Shuttle • Chosen by NASA Astronaut selection board • Almost all are military pilots • Mission specialists • Responsible for payload operations - science experiments, spacewalks, etc. • Chosen by NASA Astronaut selection board • Payload specialists • Chosen because of need for a particular scientific / engineering / political expertise not available in regular astronaut corps • Chosen by scientists with experiments on flight, or by political will • Not present on most flights • Examples: PDR, John Glenn, Ilan Ramon (1st Israeli astronaut)
Space flight training • Classroom training - Shuttle equipment &operations, communications, emergency procedures, photography, …
Space flight training • Living in space
Space flight training • Space walk (EVA)
Space flight training • Flight training
Earth Observations Tifernine Sand Dunes, Algeria
Earth Observations Guadalupe Island, Mexico
Earth Observations Deforestation in Brazil
Earth Observations Red Sea and Sinai Peninsula
Earth Observations Dead Sea - Israel
Earth Observations Hurricane Elena, September 1985
Earth Observations Tibet - Himalayas
Earth Observations Taiwan
Thanks to… • Jhong-Li High School • Combustion Institute (Bernard Lewis Lectureship travel award) • NASA