A Hotspot Model for PBX Explosive Charge Ignition in a Launch Environment

ABSTRACT

The research of explosive ignition mechanisms in the launch environment is significant to determine the launch safety of explosive charge. Based on the two-phase flow theory, the internal ballistic process and the projectile base pressures are calculated accurately. The stress history of PBX explosive during the 155 mm howitzer launching process is obtained based on the finite element method, and then the 1D hollow sphere pore-collapse model considering explosive chemical reaction, heat conduction, phase transition, and viscoplastic deformation processes can be developed, to describe the hot spot formation in explosive charge. Finally, a quantitative determination method with initial porosity as the index for explosive ignition is proposed, contributing to the launch safety determination and performance evaluation of explosive change.

KEYWORDS:

• Launch environment
• launch safety
• pore collapse
• pore temperature
• initial porosity

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research work was supported by the Fundamental Research Funds for the Central Universities [Grant No. 30919011287] and the Institute of Launch Dynamic, Nanjing University of Science and Technology, Nanjing, China.