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Paul D. Ronney Dept. of Aerospace & Mechanical Engineering University of Southern California Los 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 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 • 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 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)

Paul Ronney Paul Ronney

What is gravity? · 4 forces of nature · · · · Gravity force 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 Jupiter 2. 5 g Gravity on the planets and the moon Earth 1 g Jupiter 2. 5 g Moon 1/6 g Mars 1/3 g Saturn 1. 1 g

What happens when there is no gravity? • “Microgravity” (µg) • Simple example - 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 1 g µg

Why study microgravity? Material science Earth-grown crystal: defects in structure Space-grown crystal: nearly perfect Why study microgravity? Material science Earth-grown crystal: defects in structure Space-grown crystal: nearly perfect structure

Biotechnology Biotechnology

Fundamental physics Einstein predicted that space-time is warped by gravity Satellite experiment to test 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 How do we remove gravity? - free-fall Japan Microgravity Center - Kamisunagawa, Hokkaido Largest microgravity facility on earth

JAMIC drop shaft JAMIC drop shaft

Aircraft flying special paths Aircraft flying special paths

Orbiting spacecraft Orbiting spacecraft

International Space Station International Space Station

Example of microgravity research - “FLAME BALLS” • Predicted by Russian physicist Yakov B. 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 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 Flame balls - history • Results confirmed in aircraft flights, but aircraft vibrations problematic

Implementation of space experiment • Need space experiment - long duration, high quality µg 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 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 Experimental apparatus • • Combustion vessel Spark ignition system Video cameras Temperature, pressure, heat transfer

Flame balls - practical importance • Fire safety in manned spacecraft - space shuttle 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

Practical importance Practical importance

Flame balls in space • Stable for more than 500 seconds (!) • Weakest Flame balls in space • Stable for more than 500 seconds (!) • Weakest flames ever burned (1 – 2 Watts/ball) (birthday candle ≈ 50 Watts) 4. 0% H 2 -air, 223 sec elapsed time 4. 9% H 2 - 9. 8% O 2 - 85. 3% CO 2, 500 sec 6. 6% H 2 - 13. 2% O 2 - 79. 2% SF 6, 500 sec

Astronaut Janice Voss with Zel’dovich’s watch Astronaut Janice Voss with Zel’dovich’s watch

Re-flight on STS-107 / Columbia mission • SOFBALL mission re-flown on STS-107 / Columbia’s 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

Crew operations Crew operations

Thanks Dave, Ilan, KC and Mike! Thanks Dave, Ilan, KC and Mike!

…and the rest! …and the rest!

Space flight training • 2 types of training • Orbiter-related • Launch & entry 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, 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 (1 st Israeli astronaut)

Space flight training • Classroom training - Shuttle equipment &operations, communications, emergency procedures, photography, Space flight training • Classroom training - Shuttle equipment &operations, communications, emergency procedures, photography, …

Space flight training • Living in space Space flight training • Living in space

Space flight training • Space walk (EVA) Space flight training • Space walk (EVA)

Space flight training • Flight training Space flight training • Flight training

Perspective on space flight training Perspective on space flight training

Earth Observations Tifernine Sand Dunes, Algeria Earth Observations Tifernine Sand Dunes, Algeria

Earth Observations Guadalupe Island, Mexico Earth Observations Guadalupe Island, Mexico

Earth Observations Deforestation in Brazil Earth Observations Deforestation in Brazil

Earth Observations Red Sea and Sinai Peninsula Earth Observations Red Sea and Sinai Peninsula

Earth Observations Dead Sea - Israel Earth Observations Dead Sea - Israel

Earth Observations Hurricane Elena, September 1985 Earth Observations Hurricane Elena, September 1985

Earth Observations Tibet - Himalayas Earth Observations Tibet - Himalayas

Earth Observations Taiwan Earth Observations Taiwan

Thanks to… • Jhong-Li High School • Combustion Institute (Bernard Lewis Lectureship travel award) Thanks to… • Jhong-Li High School • Combustion Institute (Bernard Lewis Lectureship travel award) • NASA