Computational Study of Water Mitigation Effects On An Explosion Inside A Vented Tunnel System

摘要

The effects of water in close contact with detonating high explosives have been studied experimentally by numerous researchers, such as Eriksson (1974), Keenan & Wager (1992) and etc. These tests series had demonstrated that when water was stored closed to the high explosives, both the maximum overpressure and impulse density could be reduced significantly. This reduction has been attributed to the loss of energy from the shock into breaking up the water into droplets and the process of phase change of water from liquid to gas due to shock vaporization which subsequently, reduces the surrounding temperature. The purpose of the present work is to study computationally the mitigation effects of water to an explosion inside a tunnel system with venting. A series of three-dimensional numerical calculations using a Multimaterial Eulerian Finite Element code, MSC-Dytran, has been conducted. In order to capture the behavior of water subjected to shock loading, appropriate equation of state for water has to be determined. This is based on experimental data for shock Hugoniot for water and the Mie-Gruneisen equation of state for water has been chosen. Results from the present study show that water is capable of reducing the peak pressure due to an explosion and the configuration of water surrounding the explosive is important for water mitigation to be effective.