A tiny, enclosed flame onboard the International Space Station (ISS) could someday help researchers better predict the spread of massive, deadly wildfires. A new study funded by the U.S. National Science Foundation (NSF) and sponsored by the ISS U.S. National Laboratory aims to use the microgravity conditions of space to better understand how flames spread on Earth.
Principal investigator James Urban, assistant professor of fire protection engineering at Worcester Polytechnic Institute (WPI), and his team will leverage the ISS National Lab for an experiment that could help parse some of the prime forces behind wildfire spread. Successful results could contribute to more effective fire management and response measures, potentially saving lives and homes from destruction. This investigation was awarded through a joint solicitation from NSF and the Center for the Advancement of Science in Space, Inc. (CASIS), manager of the ISS National Lab, for research in the field of transport phenomena.
Urban’s study will involve complementary ground-based and microgravity experiments that will precisely measure how a flame spreads along the surface of a combustible object inside a miniature wind tunnel, under a dynamic rate of airflow. The “nonsteady” airflow approximates variable behavior in the flames that drive flame spread, allowing Urban’s team to model “intermittent” flame behaviors that can better predict how fire spreads in nature.
“Right now, our ability to develop a physical wildfire model and use such a model to predict what an active wildfire will do in a useful timescale is very limited,” Urban said. “By understanding how flames behave on a smaller scale, we can gain insight and apply that to wildfire behavior.”
Performing the experiment in microgravity will allow the team to eliminate the effects of gravity-driven buoyancy and convection, which along with wind can affect how a flame behaves. On Earth, buoyancy drives convection, causing warmer, lighter air to rise above the cooler, heavier air around it and causing dynamic flame behaviors like flickering, puffing, and dancing. By comparing flame behavior in space with ground-based results, Urban and his team can better investigate how nonsteady flame behavior driven by buoyancy and external or “forced” airflow could drive flame spread on Earth.
Urban’s research could contribute to a future “theory of wildfires” that could help researchers model the conditions that cause a wildfire to grow and spread. Such knowledge could lead to better predictions of the speed and direction in which fires will spread and how best to mitigate them, providing further protection for at-risk communities and critical infrastructure.
“The ultimate goal is to reduce the loss of lives, structures, and the danger posed to responders,” Urban said. “If we have a deeper understanding of the physical processes driving wildfires, we can recreate hypothetical wildfire situations and design communities to be more resilient against them. We can better predict under what conditions we can do safe, controlled burns. And when we do have extreme fires, we can better predict how the fire is going to behave and allocate resources appropriately.”