Abstract:

The influence of aluminum powder content on the energy output characteristics of RDX-based aluminized explosives is studied.The free-field static explosion tests are conducted on aluminized explosives with aluminum powder contents of 20%,30%,and 40%.The overpressure-time curves of free-field and ground shock waves are measured using overpressure sensors,and the propagation processes of incident waves,reflected waves,and Mach waves,as well as the changes in the explosion fireball are captured using a high-speed camera.The JWL-Miller parameters of the aluminized explosives are calibrated based on the test results.The test results show that the peak overpressure and specific impulse of ground reflected wave of the aluminized explosive are slightly affected when the aluminum powder content increases from 20% to 30%.When the aluminum powder content increases from 30% to 40%,the peak overpressure of ground reflected wave is decreased by 2.17% to 7.81%,and the specific impulse is decreased by 0.29% to 12.17%.When the aluminum powder content increases from 20% to 40%,the maximum diameter of explosion fireball increases from 6.48m to 7.12m,and the time when the explosion fireball begins to shrink increases from 20ms to 60ms.The maximum errors of the blast shock wave parameters (peak overpressure and specific impulse) of 30% and 40% aluminized explosives predicted using the JWL-Miller parameters are 16.75% and -8.51%,respectively,compared with the test results,and the average absolute percentage errors are 6.76% and 4.14%,respectively.This study can provide reference and guidance for the prediction of the power field of aluminized explosives.

Key words: aluminized explosive, peak overpressure, specific impulse, explosion fireball, JWL-Miller parameter