Fast Cook-off Thermal Protection Effects of Inner and Outer Heat-insulating Composite Structures of Explosive Charge
In order to study the thermal protection effects of the inner and outer heat-insulating composite structures ( inner heat-insulating material/outer combustion-insulating material ) of explosive charges under the condition of fast cook-off ( burning ) , the multi-point temperature measurement fast cook-off experiments are carried out on explosive charges with various forms of inner and outer heat-insulating composite structures. The temperature-time curves of flame and each measuring point of explosive charge and the ignition response time of the charge are obtained. The fast cook-off ignition of explosive charges with different inner and outer heat-insulating composite structures is numerically simulated to obtain the influence law of inner and outer heat-insulating composite structures on the ignition response time of charge under fast cook-off. The results show that the thermal conductivity of the outer combustion-insulating material is increased and its thermal insulation is weakened due to the burning and denaturation of the material during the process of fast cook-off experiment. This effect should be considered in numerical simulation. The ignition response time of explosive charge is delayed with the increase in the coating thickness of both heat-insulating and combustion-insulating materials, whether using separate insulating/combustion-insulating materials or inner and outer heat-insulating composite structures. The inner and outer heat-insulating composite structures have better thermal protection ability and can significantly delay the ignition response time of the charge. The ignition position all occurs at the corner of the end face of the charge, and the reaction intensity after ignition is not affected by the inner and outer heat-insulating composite structures and is always the deflagration. For insulating/combustion-insulating materials within a certainprotection performance range, the composite structure has the best heat-insulating effect when the coating material on the outer surface of the shell is HGN and the coating material on the inner surface of the shell is GXTI, and when the required heat-insulating effect is given, it is possible to consider increasing the coating thickness of the outer surface coating of the shell first to achieve the optimal thermal protection effect of inner and outer heat-insulating composite structures with minimum coating thickness . The research results provide reference for improving ammunition thermal safety design.
万方数据
维普
