Gas flame over black backgroundIgniting knowledge
Engineers from UC Berkeley and NASA have teamed up to conduct remote, robot-operated flammability testing aboard the International Space Station. Known as the Material Ignition and Suppression Test (MIST), this research will help designers select safe materials for space suits, spacecraft cabins and space habitats.
MIST researchers are investigating the flammability of acrylic plastic, specifically, plexiglass. A lighter-weight alternative to glass, this material could someday be used in new spacecraft windows, helping to increase fuel efficiency. Findings from these experiments will also be applicable to other thermoplastics, such as electrical wire insulation, electronic boards and spacecraft cabin paneling.
“Through these experiments, we hope to improve our understanding of early fire growth behavior and validate models for material flammability,” said Carlos Fernandez-Pello, Professor of the Graduate School, Department of Mechanical Engineering. “This will help NASA select safer materials for future space facilities and determine the best methods for extinguishing fires in spacecraft.”
During their first round of experiments, the researchers discovered something new: materials are combustible at oxygen concentrations well below those in normal gravity.
“In normal gravity, the limit of the oxygen concentration at which materials are flammable is approximately 18%. We are finding that in the Space Station, in the spacecraft environment, it’s about 15%,” said Fernandez-Pello. “We were expecting that it would be lower, but not that low.”
For Michael Gollner, associate professor of mechanical engineering, this finding offers new insight into potential fire risks in space. “Whether the change in this limit is due to air flow velocity or gravity, it means that materials can burn in space that aren’t able to burn on Earth, or that they can sustain a flame for a longer period,” he said.
MIST marks the sixth experiment that Fernandez-Pello has led with NASA. His first was in 1997 with the Kennedy Space Center. Since then, his continued work with the space agency’s microgravity fire program has helped foster a strong, lasting connection between Berkeley engineers and NASA scientists.
“It’s been almost 30 years of Berkeley students participating in these projects, which have become more sophisticated as spacecraft have evolved, as NASA has evolved,” he said. “It has been a tremendous experience to work with astronauts, not only as a researcher but as an academic and a teacher.”
Learn more: NASA-funded project offers new insights into fire behavior in space