Research On DNAN Based Melt-cast Explosive Charge And Lunching Safety

Explosives charge quality is a key factor of explosives launch safety impact,improving explosive charge quality is the most fundamental way to ensure the safety of the launch.DNAN base because of its high-energy cast insensitive explosives characteristics widely at home and abroad are active substituent group cast TNT explosives.Therefore,to cast explosive charge DNAN group safety study emission can provide key technical support for the development of a new generation of insensitive munitions,it has great military value.For the bottom gap defect,the paper use numerical simulation method to study the DNAN group cast explosive charge in typical formula(a formula:(DNAN 39.1 / RDX 57 / aids 3.9);two formulations:(DNAN 34.1 / RDX 62 / aids 3.9);three formulations:(DNAN 29.1 / RDX 67 / aids 3.9))emission safety conditions,the main contents include:(1)measuring the DNAN cast explosives based thermodynamic parameters provide the necessary material parameters for the numerical simulation DNAN group cast explosive emission security;(2)The effect of base gap temperature model and explosive thermal decomposition reaction mechanism functions to launch safety numerical simulation results;(3)to simulate the base gap thickness and chamber pressure conditions DNAN group cast explosive charge emission security studied.The results obtained and the main conclusions include:(1)Different substrate gap temperature model Explosive launch safety of simulation results a tremendous impact.This paper compares the two substrates gap temperature model,a model that will be the end of the compression process gap with the ideal gas equation of state to describe another model is with BKW equation.Compared with the BKW equation of state model,the ideal gas equation of state model ignores the volume and intermolecular forces between the molecules,so that the bottom gap temperature model calculates the ideal gas equation of state is much higher.(2)Different explosive thermal decomposition reaction mechanism functions in the form of numerical simulation of small explosive charge emission security impact.In the numerical simulation of the actual launch safety,you can assume that the mechanism of function()= 1,that is treated as zero order reaction.(3)The thickness of the larger base gap,the lower the drug loading launch safety.In a recipe,for example,in a typical chamber pressure(= 720MPa,= 10ms)under conditions when the base gap thicknesses of 1 mm,1.5 mm and 2 mm,the maximum temperature of the bottom gap was 485 K,515 K and 540 K.(4)In a typical chamber pressure = 720MPa,= 10ms conditions,DNAN group cast explosive charge in the bottom three formulations critical gap thickness was 2.526 mm(formula I),1.641 mm(formula II)and 1.575 mm(formula III).(5)Chamber pressure conditions have a major impact on the transmission security.Under certain conditions bore stress rate,peak chamber pressure,the lower the emission safety;under certain conditions,the peak chamber pressure,chamber pressure stress rate is higher,launch safety also lower.However,compared with the peak chamber pressure,chamber pressure stress rate of emission is small explosive charge security impact.