The Experimental And Theoretical Research For Technology About Charge Structure And Ignition By Detonation Under High Surcharge

The ignition by detonation was researched in this thesis which can make the ignition delay time to achieve several hundred microseconds, firing characteristic of the ignition mode was studied by mechanism test,theoretical analysis and numerical simulation. A charge arrangement was designed which can make the loading powder to endure a high overload, stability of the loading powder and firing characteristic and flame propagation characteristic of the charge arrangement were studied by live firing test and two-phase flow numerical simulation, the major works were done in this thesis as follows.1) The in-line detonation igniter was designed, the feasibility of high speed ignition by detonation was validated and firing condition of experiment with the ignition mode was researched by the experiment of static firing, it is concluded that the ignition delay time can achieve three hundred microseconds by using the ignition method,and it has high precision of ignition time.2) The layered charge structure was designed, which can make the loading powder to endure a high overload,the feasibility of layered charge structure was validated by the experiment of artillery fire, it is concluded that the loading fine grain propellant with the layered charge structure has nicer stability and integrity when it endured 20000g-40000g overload and the duration time of overload achieved 10ms～20ms.3) The experiment of static firing by detonation was done when used the layered charge structure, and the firing characteristic and flame propagation characteristic was researched, it is concluded that the ignition delay time can achieve three hundred microseconds,the pressure rapidly rised after beginning of powder firing, and propellant gas can rapidly flow, it validated the layered charge structure has nicer flame propagation characteristic.4) A theoretical calculation model of high speed ignition by detonation was set up based on the static experiment and the special structure of experimental set-up, the theoretical calculation model applied explosion mechanics,combustion theory,hydrodynamic theory of detonation and so on, the main parameters of ignition process in typical charge arrangement were calculated by programming language with Runge-Kutta, this conclusion is valuable in the application of high speed ignition by detonation in engineering,for example it can supply references to the structure design of ignition port,the structure design of charge,accelerating strength attenuation of detonation wave and so on, at the same time, mechanism of the high speed ignition by detonation was summed up based on the detonation wave theory and powder burning theory, this conclusion points out the function of detonation wave in the process of ignition, and grows understand on firing characteristic of the ignition by detonation.5) The axialsymmetry two dimension-two phase flow model was established about the layered charge structure when used the ignition by detonation, which based on the two-phase flow interior ballistics, the main parameters of ignition process were calculated by programming language, some typical computed results were listed. Based on the analysis of computed results, we can understand the firing characteristic and flame propagation characteristic of the ignition process, it is concluded that the layered charge structure when used the ignition by detonation is controllable and feasible, which can achieve the demand of engineering.6) The impact to flame propagation characteristic of the layered charge structure was computed and analysed when diameter of fire hole changed, it is concluded that there is little impact to the total time of ignition process when diameter of fire hole changed in certain range, and the ignition propagation structure used in test is rational.