Research On The Action Mechanism Of Magneto-Hydrodynamic Explosive Loading

Magneto-hydrodynamic explosive loading technology is a new concept technology for the future development in the field of high-efficiency damage, in which media are directly formed into damage elements or the traditional damage elements are acceletrated by pulse magnetic dynamic load which is generated by a high field magnet powered by a flux compression generator (FCG). The magnetic field focusing methods are innovatively applied in this technology so that the explosive energy in the non-driven direction is converted into electromagnetic energy, and higher total energy conversion efficiency of explosive is acquired. According to theoretical analysis, as long as the energy supply is sufficient, the peak value of the magnetic load has no limits. The peak value of the magnetic load could exceed the explosive load, so the damage elements are formed by the magnetic load would be more efficient.In the future, the achievements of this technology would be widely used in a variety of ammunition design, such as anti-hard structure munitions, anti-armor munitions, anti-missile ammunitions, etc. It is of important theoretical value and guiding significance to carry out mechanism research on this technology at the present time, and this work would also promote the development of other new concept high-efficiency damage technologies.The following aspects are included in this paper:(1) Research on theoretical model of the magneto-hydrodynamic explosive loading processUnder the hypothesis of physical fields acting respectively, the magneto-hydrodynamic explosive loading process is divided into three physical fields of "circuit","magnetic field" and "field of force" which act simultaneously in effect.The equivalent circuit model, magnetic field calculation model and magnetic dynamic loading model are used in succession, so the theoretical model of multiple physical fields coupling for deccribing this process is established.(2) Research on coupling of FCG with high field magnetsIn view of the theoretical model in (1), the matching relationship of FCGs and high field magnets, and the magnetic field distribution characteristics of high field magnets of different structures driven by FCGs are studied. Further more, according to the requirements of damage elements formed by action media, the structures of high field magnets are optimized.(3) Research on media forming loaded by high field magnetsBasing on an analysis of the influential factors on media forming, according to theoretical model, also with numerical methods, the preliminary law of media forming loaded by conventional multi-layer parallel high field magnets which are powered by pulse capacitors is acquired, and the forming efficiency is analyzed in the meanwhile. This work provides guidance for a follow-up research about system simulation and relevent experiments of the magneto-hydrodynamic explosive loading process.(4) Research on system simulation of the magneto-hydrodynamic explosive loading processUsing the circuit parameters calculation program, Maxwell and AUTODYN software, charge and intrinsic flux loss coefficient of FCGs the influence on its performance is analyzed, the initial input current value of FCGs is also optimized. Finally, on the condition that high field magnets are powered by FCGs, the law of the magnetic field distribution and the forming characteristics of media of different structures are forecasted. This work provides estimated results and design guidance for experimental research of live ammunition.(5) Related experimental research of magneto-hydrodynamic explosive loadingPrinciple experiments, simulation experiments and live ammunition experiments are carried out respectively. In the principle experiments, technical concepts are identified, the feasibility is determined, and some macroscopic phenomena are recognized. In the simulation experiments, impact deformation of the media made of two types of materials and with different structures is studied; the results of the theoretical model and simulation are identified also.This work prepares basic conditions for the live ammunition experiments.In the live ammunition experiments, preparatory work such as calibration of measurement system, process design and machining of key devices is done at first, then the live ammunition experiments are carried out, the theoretical model and simulation model are systematically identified finally.