Opposed Flow Flame Spread in Normal, Enhanced and Reduced GravityExperimental and theoretical aspects of opposed-flow flame spread over solid fuels are presented with emphasis on the microgravity environments of spacecraft. For high opposing flow velocities, spread rate decreases with increasing velocity eventually leading to flame blowoff due to kinetic effects. At low opposing flow velocities, where diffusional effects are slowed and radiation becomes important, flame spread rate increases with increasing flow velocity. Extinction at low velocities is due to radiative effects. Modeling efforts that include radiation, both solid surface radiation and gas-phase radiation, predict qualitatively the experimental trends observed. Computationally, gas-phase radiation is conveniently included in solution of the conservation equations by employing a Plank mean absorption coefficient, a fraction of radiation that is fed back to the surface, and a shape function that describes the radiative flux distribution along the surface.
Document ID
19920030274
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Altenkirch, Robert A. (Mississippi State Univ. Mississippi State, MS, United States)
Bhattacharjee, Subrata (Mississippi State Univ. Mississippi State, MS, United States)
West, Jeff (Mississippi State University Mississippi State, United States)
Olson, Sandra L. (NASA Lewis Research Center Cleveland, OH, United States)