Measurement of Transient Thermal Effects of Explosion Using Slug Calorimeter

Measuring thermal damage caused by explosion is crucial for ammunition research and safety protection engineering. However, the transient characteristics and harsh environment of the explosion pose challenges to measuring this process. In order to measure the heating effect of explosion on the target, based on one-dimensional heat conduction in a flat plate, a new slug calorimeter was developed. The basic structure of the calorimeter consists of a copper plate with a thickness of 0.2mm and an infrared thermopile, by measuring the temperature and temperature rise rate on the back of copper plate, the heat dose(J/m<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</i>) and heat flux(W/m<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</i>) are obtained respectively. The use of an infrared thermopile instead of a thermocouple for temperature measurement minimizes heat loss from the copper plate. The sensitivity and response time of calorimeter are obtained on a large-area optical fiber laser heat flux calibration platform. The calibration results demonstrate that the calorimeter's response time to a step heat flux is better than 4 ms. The explosion experiment of 17.5 kg TNT was carried out in open space, regarding the calorimeter's measurement results, the heat dose is not only more accurate than the heat flux, but also more in line with the damage mode of transient thermal action. The proposed calorimeter provides an effective method for measuring the transient thermal effect of explosion on targets.