Study On Combustion Gas Flow And Spreading Laws Of The Double-base Propellant Fire In Confined Space

In this dissertation, the combustion gas flow and spreading laws of the double-base propellant fire in confined space was studied. First, based on the steady combustion mechanism of double-base propellant, the combustion features of the propellant in air were demonstrated. The flame was converted to diffusion flame in propellant fire, and it was attributed to a secondary combustion of CO and H2, which was derived from the fizz zone of the propellant combustion, with O2 in air. Second, the gas flow and spreading character of small-scale combustion of double-base propellant was simulated by FLUENT software. The eddy-dissipation/Arrhenius reaction model was selected,κ-εturbulence model was loaded, and a reasonably boundary conditions and control parameters were set in the simulation process. In addition, the experimental study was carried out to validate the simulation results, and the experimental results show it is viable to simulate the fire of double-base propellant by FLUENT software. Finally, fires at different conditions in a single room of double-base propellant were simulated, and the gas flow and spreading laws of the propellant fires at different factors were analyzed and compared. The results show that the development of fire is rapidder. the temperature, oxygen consumption, and toxicity of gas at propellant fire site is higher compared with ordinary building fire. Besides, the spreading character of propellant fire gas is greatly influenced by initial oxygen concentration, ventilation conditions and ignition place. The results of this research can provide some ideas, theory and experimental data for the works about the development laws of propellant fire.