Characteristics Of Explosion Cavity And Temperature For Fuel Dispersal Driven By Explosively

The way of center charge, explosive cavity and temperature in cavity were researchedin this paper. Through researching, the factors affecting fuel symmetry and stabledispersion were found. And the results provide theoretical foundation for FAE devicedesign and have a certain guiding significance.Firstly, through the determination of high speed photography, the maximum dispersalvelocity of the coupling charge FAE device is408.5m s-1and the calculation is412.5m s-1by LS-DYNA, hence, the method is accurate and reliable. Using the same method, weresearch the dispersal velocity, explosive cavity and temperature of FAE devices withdifferent center explosive charges. The results show that in case of uncoupling FAE devices,the dispersal velocity distribution is uniform and the fuel efficiency is high while theexplosion cavity radius presents a distribution of large in the middle and small in the endswhich makes the position of second ignition equipment have more choices, at the sametime, the maximum cavity radius is as33～34times as the radius of center charge, thus, wecan judge the maximum radius of different center charge, and the temperature in cavity ofthe FAE devices using uncoupling center explosive charge drops quickly and the timedecrease with the uncoupling coefficient exponentially.Secondly, the explosive process of center explosive charge of FAE devices issimulated and the influence of the way of center explosive charge and the ratio between theouter radius of the FAE device and center pipe on the explosive cavity and the dissipationof temperature in the cavity are discussed. The analysis of results indicate both usinguncoupling center explosive and increasing the ratio between the outer radius and the radiusof center pipe can decrease the cavity of center explosive charge, which and also acceleratedissipation of temperature in explosive cavity.Thirdly, the offset of the center charge and shell weakening in one side for fueldispersal were studied by using LS-DYNA. The calculation results show that axial offsetswould cause radial dispersal velocity uniformity in the axial. The results indicate the radialoffsets of center explosive charge would promote the same direction fuel dispersal andinhibition of reverse direction fuel dispersal, which is same for the explosive cavity. Andwhen unilateral weakening occurs, the dispersal velocity of fuel in both sides decrease, under the same condition, the reduce of dispersal velocity in both sides of the FAE deviceusing PVC shell is less than the FAE device using steel shell. This suggests the decrease ofvelocity is obvious when using high strength shell while was slight when using low strengthshell.This study is preliminary work and the research results can provide certain referencevalue to the post-specific outdoor test study.