Abstract
Flame spread over solid fuels in a microgravity environment is an important area of research due to its fire safety implications in spacecrafts. Of all different configurations, flame spread over thin fuels in an opposed-flow environment is the simplest and, therefore, received most attention during the past decade of research. However, the concurrent-flow configuration in which the flame is known to accelerate is more hazardous. In this paper we study the transition between the two regimes experimentally and computationally. Experimental data on flame spread rate for different oxidizer velocity, positive and negative, are obtained from experiments conducted in drop tower as well as airplane flying parabolic trajectories. An existing computational code for opposed-flow flame spread is modified to model concurrent-flow spread as a pseudo-steady phenomenon. Good agreement is obtained between the experimental and computational results.
