Electromagnetic Properties And Thermodynamic Analysis Of Solid Propellants

Composite solid propellants have good energy performance and are widely used as solid motor power sources in rockets,missiles and space vehicles.It is easily oxidized at room temperature,and even easily causes combustion and explosion in the external strong electromagnetic environment.Therefore,the electromagnetic effect and thermodynamic analysis of solid propellants are carried out,and the use and safe storage of solid propellants are all good.Significance.The main research contents of this paper:Mathematically modeled the electromagnetic absorption power,skin depth and wave impedance of GAPcomposite solid propellant under electromagnetic field irradiation.The frequency characteristics of dielectric constant and magnetic permeability of electromagnetic parameters of solid propellant are tested,and the frequency characteristics of electromagnetic absorption power,skin depth and wave impedance of solid propellant are obtained by research and analysis.The electromagnetic field is transmitted to the solid propellant through a waveguide to conduct an experimental study on the strong electromagnetic radiation effect of the solid propellant.The phenomena of bulging,burning and explosion of the solid propellant under the action of different frequency electromagnetic fields are tested,and the ignition delay period is recorded.At the same time,the electromagnetic simulation of the solid propellant was carried out,and the electric field distribution and temperature distribution of the solid propellant at different frequencies were obtained.The simulation results show that with the increase of the transmission distance of the electromagnetic wave in the solid propellant,the distribution areas of the strong electric field and the high temperature area gradually increase,and the maximum value approaches the central area.The maximum electromagnetic absorption power density of solid propellant has absorption peaks at frequencies of 3.208GHz,4.408GHz,8.006GHz,10.4GHz,and 11.2GHz,and the absorption peaks are larger at 3.208GHz,10.4GHz,and 11.2GHz.The solid propellant absorbs electromagnetic energy and is heated under strong electromagnetic radiation.When it reaches a certain temperature,a thermal decomposition reaction occurs inside,causing the temperature to rise sharply,which may cause combustion or explosion.The DSC/TG test was carried out on the solid propellant.On this basis,the thermodynamic analysis of the solid propellant was carried out,and the thermodynamic parameters of the solid propellant were obtained.The activation energy is 176.274 kJ·mol-1,the pre-exponential factor is 1.694×1018s-1,and the reaction mechanism function f(?)is 3(1-?)[-ln(1-?)]2/3,The thermally accelerated decomposition temperature is 238.58?,and the thermal explosion critical temperature of the solid propellant is 240.7?.Theoretical analysis of the thermodynamic equation is used to obtain the ignition delay period of the solid propellant after the internal thermal decomposition under the action of the electromagnetic field,which provides a reference for the safe storage of the solid propellant.