HOME

Science and Technology of Energetic Materials

Vol.71, No.4 (2010)

Research paper

A numerical model of laser-induced ignition of boron / potassium nitrate pyrotechnic incorporating temperature dependence of thermophysical properties(*in Japanese)
Hisahiro Nakayama, Tomonori Miyashita, Naohiko Yoshitake, and Ritsuo Orita
p.98-105

Abstract

A numerical calculation model of the laser-induced ignition of boron / potassium nitrate pyrotechnic under the condition of one-dimensional heat input was discussed. The governing equation was derived by incorporating an Arrhenius type chemical reaction source and temperature dependence of thermophysical properties of the pyrotechnic. Since the equation was nonlinear, the surface temperature profile was obtained by solving the equation numerically. The surface temperature, at which the exothermic chemical reaction could be sustained without the heat input by laser irradiation, was theoretically derived. In the process of the derivation, the exothermic chemical reaction of boron and potassium nitrate was assumed to occur in the immediate vicinity of the surface heated up by laser irradiation. Since the derived surface temperature agreed with the surface temperature measured at the onset of ignition in the laser ignition test, it was found that the derived surface temperature could be used as the laser ignition criterion. The ignition delay derived from this technique was in good agreement with the test result in the range of the laser power density utilized in the test.

Keywords

boron, potassium nitrate, laser-induced ignition, ignition temperature, thermophysical property.

© Copyright 1999-2017 Japan Explosives Society. All right reserved.