舱室内爆炸压力载荷测试方法研究

A method of testing the first reflected shock wave and the quasi-static pressure is proposed for the explosion test of the charge in a closed or quasi-sealed cabin. The frequency and amplitude characteristics of the first reflected shock wave and the quasi-static pressure formed by the in-chamber charge explosion are analyzed, and the necessity and rationality of using the different frequency response sensors to measure are illustrated. A sensor selection method is presented for using a high frequency piezoelectric sensor to measure the first reflected shock wave and a low frequency piezoelectric sensor to measure the quasi-static pressure. A special process tooling design and a sensor placement method, of which nylon sleeve tooling plays the role of insulatng and attenuating the stress wave, are presented. The design of the inner chamber pressure transmission tube can effectively eliminate the high-frequency signal generated by explosion and the interference of the optical and thermal signals on the piezoresistance sensor, thereby ensuring the test accuracy. A charge explosion experiment was conducted in the simulated cabin, and the test data is in good agreement with the calculated results of the classical formula. The research results show that the parallel test method for explosion-induced pressure load and the process tooling design is reasonable and feasible. It is recommended that the test sampling rate of the first reflected shock wave is in the order of MHz and the sampling rate of quasi-static pressure test is in the order of KHz under the premise of reasonable estimation of amplitude range of a signal to be tested. The effect of interference signal on the test is prevented using nylon sleeve tooling and an interference fit installation method.