Comparison of blast pressure profile for military and commercial explosive with different point of initiation.

Abstract

A blast wave profile caused by an explosive explosion has been thoroughly studied for several decades. The propagation profile of the blast wave under circumstances has been predicted based on a sizable amount of experimental data. However, most investigations have merely considered the explosive's centre point of initiation. In this study, the goal has been designed to compare the detonation velocities of commercial explosive (Emulex) and military explosive (PE-4), as well as to examine how different initiation points for the two types of explosives affects the blast peak overpressure value. Three points of initiation have been set to each charge which is top, centre and bottom. Experimentally, 500 g of PE-4 and 500g of Emulex were hung in the air and detonated at 1.2 metres above the ground. At various distances of 0.5 m, 1.0 m, 1.5 m, 2.0 m, 2.5 m, 3.0 m, 3.5 m, and 4.0 m, pencil probes were set pointing at the explosive to capture the data from the explosion. With high accuracy of high-speed data acquisition system (DAQ) and free field pencil probe at each distance, the blast peak overpressure was recorded. In this experiment, the fibre optic cable technology was used to measure the detonation velocity (VOD) for each explosive to validate the strength of the explosive before the blast took place. From the reading, the PE-4 was measured at 8,400 m/s whereas 5117 m/s for Emulex. The findings indicate that the PE-4 has a higher detonation velocity compared to Emulex. During the experiment, each explosive's peak overpressure has been recorded. The PE-4 explosives produced the highest among all with a top point initiation of 4.21 MPa. With respect to the commercial explosive Emulex, the highest pressure of 3.12 MPa has been recorded also at the top point of initiation. The findings demonstrate that for both types of explosives, the top point of initiation produces the largest peak overpressure, followed by the bottom point, while the centre point of the explosion recorded the lowest peak over pressure.