In the coming decades, astronauts are expected to travel in space for long stretches of time. That’s why new methods are needed to prevent what would be a catastrophe aboard a shuttle or space station: fire.
Mun Y. Choi, dean of the School of Engineering, has been working on the issue of combustion and fire suppression since 1994, and an experiment of his recently traveled aboard the U.S. space shuttle Endeavour to the International Space Station for testing.
The first phase of Choi’s research – which he is conducting in conjunction with NASA, Princeton, the University of California-San Diego, and the University of California-Davis – will investigate the behavior of isolated fuel droplets under microgravity conditions.
The second phase will investigate flame extinction, soot formation, and radiative heat transfer.
“Fire behaves much differently in microgravity environments than it does on earth,” says Choi.
“On Earth, smoke rises from the flames, but aboard a space shuttle, it would disperse in all directions because of the absence of buoyancy. This makes locating the source of the fire and extinguishing it much more difficult.”
Quenching a fire in space requires new methods that will not only put the fire out efficiently, but prevent harm to astronauts
in the enclosed environment, Choi says.
“We’re evaluating different gases that are able to extinguish a fire in that environment, such as helium or carbon dioxide, that will get the job done without causing respiratory problems for those on board,” he says.
“There is an urgency to ensure that astronauts are protected from fire, and to develop better methods of putting fire out.”
The experiment aboard the station will observe the baseline burning behavior of a microgravity flame.
Then different gases will be tested to see how they affect the rate of burning, flame temperature, and flame extinction.
Researchers will observe the influence of oxygen concentration and ambient pressure on overall burning behavior.
“This work will show how various environments and scenarios affect the flames in a low-gravity situation” says Choi, “and how the flames can best be quenched.”
Choi embarked on this work while at the University of Illinois at Chicago, in an effort to understand the fundamental burning process of liquid fuels and its impact on pollutant formation and efficiency.
The potential applications of the research are not confined to space. What is learned from the experiments conducted at the space station can also be applied to terrestrial devices such as gas turbines or internal combustion engines.
Endeavour was launched on
Nov. 14. The experiments aboard the space station will begin in January.