爆炸箔起爆器发火阈值影响因素的数值模拟

To study the influence of the transducer component composed of bridge foil, flyer and accelerating chamber on the exploding foil initiator (EFI) ignition performance and achieve the goal of reducing the ignition threshold, ANSYS/AUTODYN software was used to simulate the process that bridge foil driven flyer to detonate HNS-Ⅳ. The influence of bridge foil thickness on flyer speed was studied, and the influences of bridge area width, flyer material(organic glass, ceramic and polyimide), flyer thickness and accelerating chamber length on EFI ignition threshold were investigated. Results show that reducing the width of bridge area is helpful to reduce the ignition threshold of exploding foil initiator. Under the same input voltage, the speed of flyer driven by bridge foil with thickness of 2 μm is maximum. The ignition voltage of exploding foil initiator decreases firstly and then increases with the increase of flyer thickness, and the ignition voltage is lowest when the thickness is 10 μm. Compared with 0.225 mm, 0.250 mm and 0.275 mm accelerating chamber, ignition voltage of 0.125 mm one is lowest, so reducing the acceleration chamber length is beneficial for reducing ignition threshold of exploding foil initiator. Under the condition of determinig the accelerating bore aperture, "infinite" accelerating chamber is better than "finite" accelerating chamber for reducing firing voltage of EFI. Polyimide has better mechanical properties, lower ignition voltage and lower kinetic energy compared with other two materials (organic glass and ceramic).