Abstract: In order to improve the accuracy of the simulation calculation of fire extinguishing bombs, the main factors that affect the simulation results: the burning rate model of the generator, the simplified model of the inlet condition and the firing judgment condition of the generator, are respectively calculated and analyzed in combination with measured data. Finally, a simulation calculation model for the transient process of fire extinguishing bombs with propellant as the driving source is established, which fits well with the experimental values.The simulation results show that the selection of the burning rate model mainly affects the slope of the pressure-time curve after the ignition pressure peak; the selection of the ignition gas model mainly affects the appearance time and intensity of the ignition pressure peak;the selection of ignition judgment model can make the curve move forward or backward in time as a whole.

Key words: fire extinguishing bomb, gas generator, flow field, numerical simulation