Study On Explosive Loading Characteristics Under High Hydrostatic Pressure

In this paper,based on the demand of underwater weapons’ power improvement,the characteristics of explosive explosion load under high hydrostatic pressure are studied,and the influence of high hydrostatic pressure on underwater explosion shock wave,bubble load,penetration power and forward shock wave load of shaped charge are analyzed,which provides support for the optimization design of underwater weapons’ power and anti explosion performance of deep-sea targets.The main work and research achievements are as follows:(1)The research on blasting charge shock wave load under high hydrostatic pressure is carried out,and the simulation model of underwater blasting shock wave load of explosive is established,and the rationality of the model is verified by using empirical formula and literature data;The load distribution law of explosion shock wave under different hydrostatic pressure is analyzed through simulation calculation,and the initial state of shock wave is solved by using explosive detonation conditions and shock wave jump conditions;Finally,the engineering calculation model of peak overpressure and specific impulse of shock wave considering hydrostatic pressure is established by using dimensional analysis to fit simulation data.The results show that the hydrostatic pressure has little influence on the peak value of shock wave overpressure,but has greater influence on the contrast impulse;With the increase of hydrostatic pressure,the peak value of shock wave pressure increases,and the peak value of overpressure and specific impulse decrease.(2)The research on bubble load of blasting charge under high hydrostatic pressure is carried out,and the simulation model of bubble wave load of underwater blasting is established,and the rationality of the model is verified by literature data;The bubble pulsation characteristics and secondary pressure wave loads under different hydrostatic pressures are analyzed by simulation;The engineering calculation model of secondary pressure wave load is established by using dimensional analysis to fit simulation data;Finally,by calculating Kelvin impulse and numerical simulation of bubbles,the evolution of free field and near wall bubble morphology and the characteristics of water jet load under different hydrostatic pressures are analyzed.The results show that the hydrostatic pressure has a great influence on the bubble pulsation characteristics within the hydrostatic pressure of about 3MPa;With the increase of hydrostatic pressure,the maximum radius,pulsating period and displacement of bubble center of mass decrease,the peak overpressure of bubble secondary pressure wave increases,the specific impulse decreases,the velocity of free field bubble water jet increases,bubble water jet is more difficult to form,and the utilization efficiency of near wall water jet load on bubble energy decreases.(3)The research on the explosion load of shaped charge under high hydrostatic pressure was carried out,and the numerical simulation model of underwater explosion of shaped charge was established.The comparison of experimental results verified the rationality of the model.The load characteristics of shaped charge penetrator and forward shock wave under different hydrostatic pressures were analyzed through simulation calculation.The results showed that the hydrostatic pressure had little influence on the geometric shape and velocity of shaped charge penetrator,and as the hydrostatic pressure increased,The velocity of shaped charge penetrator decreases;Under the same explosion height,the peak value of forward shock wave overpressure first increases and then decreases along the radial direction.With the increase of hydrostatic pressure,the peak value of shock wave overpressure increases,and the increase area is mainly concentrated near the maximum point of the peak value of overpressure along the radial direction under the same explosion height.