Study On Action Mechanism Of Energetic Fragments And Damage Effect Of Experiment

In this dissertation, the explosive energetic fragment and combustion energetic fragment were studied accounting for the different damage mechanism and terminal effect, by using the analytical model, numerical simulation and experimental research. The dynamic response of energetic fragment under the shock loading, the time of reactive release, the transformation process between the react and product, the temperature of reactive release and the damage effort of the representative target were studied emphatically.1. The process of shock initiation of the explosive energetic fragment was studied. Based on the theory of shock wave and the dynamic of shock initiation in Solid Heterogonous Explosives, the P-v, E-v, E-d, etal curve of the explosive in fragment were obtained, by using the analytical model and numerical simulation. It provides a theoretical basis for quantitative researched the shock initiation behavior of energetic fragment. By combining the experimental research, the empirical formula of the critical velocity of explosive energetic fragment shock initiation was established. The new empirical formula considers the material of target, explosive, the head thickness of fragment, the ratio of length to diameter, the diameter of fragment and other parameters. The research results show that the ratio of length to diameter of fragment and shell material affect the initiation threshold velocity. While designing the explosive energetic fragment, it is beneficial to increase the ratio of length to diameter and choose the material with high density and high performance.2. The reaction release time of explosive energetic fragment impacted thin target was studied. Based on the theory of shock wave propagation, the response time of shock initiation, the model of reaction rate and the pattern of flow resistance movement, the theoretical calculated model of the reaction release time corresponding penetration depth of explosive energetic fragment impacted thin target was proposed for the first time. Several key factors of influence reaction release time was analyzed, by this calculated model. The controlled release time of design method was given for explosive energetic fragment shock to different target according to the research conclusion.3. The damage effect of explosive energetic fragment was studied. Several key factors including head shape, diameter of fragment which influence shielded explosive shock initiation process were studied. By combing the numerical simulation and experimental research, the physical image that the explosive energetic fragment shock initiation the shielded explosive was shown, and the damage mechanism of explosive energetic fragment was clarified. The different damage mechanism of explosive energetic fragments and inert fragments is found. The damage mechanism of inert fragments is a kinetic energy of impact, but the explosive energetic fragment is an explosive chemical reaction energy. The explosive chemical reaction energy is caused by impacted shock wave.4. The material of the combustible energetic fragment of shock compression properties and schok temperature was studied. Besed on the MORSE potential function of the solid material of cold energy and cold pressure, the calculated method of porous mixture of shock compression curve was improved and simplified. The calculated and analytic results by the new method presented are more agree with the corresponding experiments results than the existing methods. In addition, the shock temperature of the material of combustible energetic fragment was theoretically analyzed for the Hugoniot adiabat, state parameters and isovolumic extrapolation of solid materials. By combining the calculated cold energy, cold pressure and the Hugoniot equation of solid metal and porous metal, a new method for the shock temperature of porous metal was presented. The influence of several thermal physics parameters includeing the temperature of solid materials, Gruneisen coefficient, electronic Gruneisen coefficient and electronic specific heat coefficient on the calculated the value of new method was discussed. The calculated results according to the new method presented are agree well with the corresponding experiments results. The shock temperature of porous metal can be little influenced by Griineisen coefficient and electronic Gruneisen coefficient, but it can be influenced evidently by material compactness, shock pressure and electronic specific heat coefficient.5. The SICR model of the combustible energetic fragment and the damage to the diesel oil tank were studied. The pressure controlled factor was considered for the Arrhenius reaction rate model. The new reaction extent is a comprehensive reaction extent model that the influence of reaction time, system temperature and pressure was considered. By combing the shock compression equation react and product, the new shock compression calculation model of MESMs was presented. This model included the reaction extent, the react, product EOS and the reaction energy. From the physical essence, this model considered the transformation of react EOS to product EOS and the new reaction extent, comprehensive. So it can better reflect SICR process, while the calculated results by the new model presented arc more in agreement with the corresponding experiments results than the existing models. In addition, The research results show that the shock temperature of MESMs and the released reaction energy are influenced by pressure, porous and reaction rate, and the foregoing factors are interaction. The damage experiment of the diesel oil tank was also studied. The damage of combustible energetic fragment was compared to the damage of the inert fragment. The main influence paremeters of the different damage were given by quantitative. Further more, the possible influence paremeters of un-ignition and an optimum design method of energetic fragment's warhead was presented.