SOLID-PROPELLANT FIRE IN AN ENCLOSURE FITTED WITH A CEILING SAFETY-VENT

The response of an enclosure having a ceiling safety-vent to a fire of solid propellant located on the floor is investigated numerically. Th e full Navier-Stokes equations are solved along with the species conti nuity equations. A recent method is used to compute chemical equilibri a and the coupling between chemistry and thermodynamics is treated acc ording to a new strategy. The particular boundaries, which are the com bustion zone of the propellant and the outflow section, require an ori ginal treatment by solving a set of 'full' or 'half' Riemann problems taking into account the transport of chemical species. The SOLA-ICE al gorithm is successfully developed for the reactive-diffusive case deal ing with particular boundaries. A fire of a standard hot homogeneous p ropellant in a rectangular cavity initially filled with air is simulat ed for two opening conditions of the safety-vent. They predict the inc rease in the rates of energy release and CO2/H2O production in the rea ction zone caused by afterburning processes involving the air of the e nclosure. The course of the compartment fire is described in terms of time evolution of the average gas temperature and pressure, and oxygen depletion for both opening configurations.