Numerical Calculation And Experimental Study On Underwater Detonation Of Deep Water Emulsion Explosive

In deep water environment,due to the effect of static pressure,the hollow glass beads used for sensitization in emulsion explosive will be broken,which will lead to the decrease of porosity and density of emulsion explosive,and then the detonation speed and brisance of emulsion explosive will be decreased.Not only that,but also the initiation sensitivity and detonation transmission sensitivity will be reduced.In this paper,the initiation mechanism of deep-water emulsion explosive is studied,and the process of pore closure in the initiation process is numerically simulated,and the relevant experiments are carried out to characterize the role of hollow glass beads in the detonation process.Firstly,this paper introduces the mathematical model of initiation and detonation wave of glass bead emulsion explosive,and gives the calculation formula of detonation pressure,detonation heat and detonation velocity of unit mass glass bead emulsion explosive.Compared with published data,the error is less than 10%.Secondly,ANSYS / LS-DYNA is used to simulate the pore closure process of hollow glass beads in emulsion explosives.According to the relevant parameters of the calculation model of the mass fraction formula of the hollow glass beads in the emulsion explosive,the pressure,wave velocity and energy change of the detonation wave are analyzed.Through the simulation results,it is found that the internal energy of the air bubble inside the hollow glass bead will increase significantly after the detonation wave,The results show that the structure of hollow glass beads will be damaged to a certain extent in deep water environment.The experimental results show that the breakage rate of hollow glass microspheres shows a certain rule under the experimental conditions in this paper.The crushing rate of hollow glass microspheres has no direct relationship with the pressure time.After 10 hours of pressure at 3 ATM,the breakage rate of hollow glass microspheres has no direct relationship with the pressure time The crushing rate is basically stable.Under the pressure of 0.3MPa and 24 h,the crushing rate of HK20 hollow glass bead(2# bead)produced by a factory is only 9.54%,which can meet the deep water detonation of emulsion explosive.Finally,the detonation velocity measurement experiments of emulsion explosives in simulated deep water are carried out.The results show that the emulsion explosives sensitized by 2 # micro beads can still detonate completely within 24 hours under the condition of 3ATM static pressure(about 30 m water depth),and 1 # micro bead sensitized emulsionexplosive can still detonate completely within 24 hours It is concluded that it is important to maintain the porosity of emulsion explosive for detonation.