Preprocessing analysis of free-field pressure data in explosive power testing of underwater weapons
Abstract
<p indent="0mm">Experimental measurements in the explosive testing of underwater weapons are important tactics to obtain the explosive power of a weapon. Preprocessing measurement data in the free-field pressure test is an important basis for approaching and extracting the true values of the measurement signals. By analyzing and calculating characters from the processed data, the explosive power value of weapons can be reasonably assessed. In this paper, we investigated preprocessing methods to eliminate common interference noise in free-field pressure tests, such as time-domain curve tendency, power frequency interference, interference between test channels, and rising edge error of shock wave impulses. The underwater free-field pressure data tested by the pressure sensor obtained in the explosion test was used to study the preprocessing flow design. It was processed by polynomial fitting to remove tendency item, serial conjugate gradient method to remove power frequency interference, moving window medial filtering to reduce pulse interference, and exponential function fitting to correct the rising edge of shock wave impulses. A preprocessing flow was designed for underwater free-field pressure measurement data. Its validity was evaluated by the comparative analysis of time domain and frequency domain characteristics and statistical characteristics of the data before and after preprocessing. The serial conjugate gradient method significantly reduces power frequency interference at certain frequencies and affects signals with other frequencies scarecely. In the exponential fitting of shock wave impulses, the relevant parameters of the fitting curve were optimized by the truncated Newton method. The effect of the exponential fitting of the peak value correction was evaluated by power error and peak value error.</p>
