Fire Suppression in Microgravity: Dynamics of a Polydispersed Water Mist Around an Obstacle

Abstract

The work presented here aims at characterizing the dynamics of water mist during fire suppression events in cluttered spaces. To this end, a numerical model for a polydispersed water-mist is used. A sectional approach is used to describe the mist behavior. The distributions of the parameters characterizing the mist (size, speed, and direction at injection) are discretized in classes, and they are chosen using a Monte Carlo method. The fate of the droplets in each class is determined by calculating the history of a representative droplet for each class using a Lagrangian approach. The dynamics of the representative droplets and their heat and mass transfer histories are tracked. An extended-film model is used to evaluate droplet evaporation. This mist model interacts in a one-way coupled manner with a pre-calculated flow field around hot obstacles.

Numerical Investigation of Water Droplet Impact on Solid Surface in Microgravity

“…Abbud et al [1,7] also used ground experiments and numerical simulation method to study water mist suppression of three typical spacecraft fires. Lewis et al [8] studied dynamics of a polydispersed water mist around an obstacle in microgravity. Schwer [9] used simulation method to study water-mist suppression of flame in different gravity environment including Earth, Mars and Lunar gravity.…”