Light emission from high explosive samples in a detonation chamber

Abstract. Dynamic measurement of high temperatures in explosives testing is usually performed using multi-channel pyrometry, i.e. by analyzing the intensities of emitted light at different wavelengths. One of the key issues in pyrometry is the correct selection of spectral bands ensuring that the captured light is of thermal origin and atomic and molecular emission peaks are excluded. Four explosive samples were involved in this study: PETN-based moldable plastic explosive, liquid explosive based on nitromethane, powdered PETN and its mixture with aluminium powder. The light emission was collected simultaneously by a time-integrating spectrometer and a time-resolved multi-band pyrometer. The tests were performed in a lab-scale detonation chamber and the light was captured by fiber optic probes mounted at a distance from the sample to collect the light originating from the expanding fireball of detonation products. The pyrometric results are discussed with respect to the observed spectral features.