Production of Diffusion Flames in the Near Extinction Limit Regime Using a Hele-Shaw Apparatus in a Simulated Low Gravity Environment

A Hele-Shaw apparatus that produced spreading diffusion flames in the near extinction limit was designed and constructed. A scaling analysis was used to determine the maximum test section height for which effects of gravity could be neglected. Preliminary results showed that this apparatus could be used to produce flame instabilities which resemble drop tower test results from NASA [1,2] and other diffusion flame instability studies [3,4,5,6]. Therefore, the Hele-Shaw apparatus is useful for studying flames in a simulated low gravity environment. Additional unstable behaviors seen in the device, such as flame pulsing and spreading blue cusps, not in the NASA testing further supported the need for investigations during longer microgravity times on the International Space Station. The initial testing was only used to gain an observable region of unstable flames. Further studies will be directed at explaining and quantifying specific behaviors with test conditions.