Study of continuous velocity probe method for the determination of the detonation pressure of commercial explosives

ABSTRACT

A novel velocity probe, which permits recording the continuous velocities of detonations and shock waves, has been developed based on the transition of operation principle from ionization to pressure-conduction. Using the new probe and the impedance matching method, a series of measuring devices were set up to obtain the shock wave velocities in different inert materials, i.e., water, Plexiglas and paraffin wax. Two test types of powder ammonium nitrate/fuel oil (ANFO), exposed on the ground and tamped in the blast hole, were performed, from which we calculated their detonation pressures, with a density of approximately 0.86 g·cm⁻³, ranged from 3.52 GPa to 3.65 GPa, and the adiabatic exponents from 2.24 to 2.30. The results show that the present velocity probe-based method can be used to determine the detonation pressure of commercial explosives conveniently and reliably, which is an important supplement for the testing techniques of explosive performance.

KEYWORDS:

• Aquarium test
• continuous velocity probe
• detonation pressure
• impedance matching
• inert materials

Acknowledgments

The authors would like to express gratitude to Senior Engineer Sun Junpeng, Drs. Miao Yusong, and Chen Xiang for their assistance in performing the experiments of the present work.

Additional information

Funding

This study is financially supported by National Natural Science Foundation of China [grant number 11272081], [grant number 11672067].