Research On The Sensitivity Characteristics Of The Detection And Control Device To The Burning Heat

In order to avoid the occurrence of the ammunition explosion caused by a fire or enemy strike,the research and development of Insensitive Munition(IM)have drawn wide attention from all over the world.The article focuses on IM high requirements for fuze technology.Based on the standard of non-sensitive ammunition burning experiment,the fuze structure was numerically simulated and the thermal desensitization of fuze was designed.It provides theoretical support for the research of insensitive ammunition fuze technology.The main contents of this paper are as follows:The temperature and environmental indexes of non-sensitive ammunition burning experiment were analyzed.Fast burning require temperature is quickly heated to 1073K and maintained 20min.Slow burning require temperature is heated to 638K at a rate of less than 3K/min.According to the experimental environment of cook-off,a mathematical model of fuze heat transfer is established.The thermal explosion model as an internal heat source is added to the heat transfer model.Electronic devices inside the hood are prone to wrong signals during the firing process.Fluent software is used to simulate the temperature of the hood with different heating rates.The thermal failure of typical electronic devices inside Fuze is analysed.The results show the temperature inside the hood and the ambient temperature is almost the same with the heating rate of 3.3K/h;When the heating rate is increased to 1.5K/s,the temperature difference inside the hood is very large,potting material shows a strong thermal insulation.The smaller crust thermal resistance is,the smaller the pin number is,the lower the line maturity is,the greater the temperature failure rate of microprocessor will be.The working voltage and rated voltage of the resistance and capacitor are selected as the best of 0.4-0.6.Fuze booster and detonator in the burning process are prone to exploding.The heat transfer model and the judgment basis of firing response of fuze booster are established.The influence of heating rate,shell material,shell thickness and explosives phase transition on the combustion response of fuze was analyzed.The results are compared with the others'experiment.The results show the higher heating rate is,the earlier the fuze booster explode,the higher hot ignition temperature is,the hot ignition position is shifted toward the charging shell and the internal temperature gradient is increased.In this paper,when the shell material is steel,it has the best thermal protection;when shell material is aluminum,it has the worst thermal protection.Low-melting explosive TNT in the firing process is prone to melting,.When TNT is melting,the temperature of fuze changes a little and the hot ignition position inside fuze booster moves up.The thermal insulation design enhance the heat safety of fuze.The influence of heat insulation material and insulating layer thickness on the ignition response of fuze is analyzed.The results show when the insulation material is airgel mat,it has the best insulation.The thicker the outer wall of the fuze is,the better the heat protection will be.