Laser Ignition of Propellants and Explosives

Abstract

Laser and radiative ignition of 24 solid propellants and explosives was analyzed. The effect of ignition criterion used to calculate ignition delays from models was evaluated. Values for the optical parameters reflection, R A and absorption, k^ coefficients at wavelengths 0.36-1,1.06 and 10.6 urn were summarized. Effects of in-depth absorption and vaporization were considered. Methods for determining the relation of ignition delays for conductive heating (R x = 1, k A = infinity) and radiative heating at various wavelengths are presented. Methods for deriving kinetic parameters for the ignition and vaporization mechanisms for RDX-based materials were developed. Changes in the ignition mechanism at high radiative flux levels are discussed. A summary of the minimum flux levels needed for ignition and the Arrhenius kinetic parameters determined from ignition delay measurements with several energetic materials is presented. List of Figures viiList of Tables ix IX INTENTIONALLY LEFT BLANK.

Mid-IR enhanced laser ablation molecular isotopic spectrometry

“…These results suggest that chemical reactions with atmosphere initiated by the addition of the long IR pulse of DP-LIBS can create enhanced molecular emission [43,44], but enhancement may depend on the initial mechanisms of breakdown [39]. For the two cases here, a given IR power density likely facilitated the evaporation and explosive decomposition or burning of TNT, which has been personally observed by the current authors and others studying this effect [45][46][47], but polystyrene simply fragmented due to better chemical stability, as evidenced by the melting and boiling points of these two materials. Trinitrotoluene has an 80 °C melting point and a 240°C explosive boiling point; polystyrene has a melting point greater than 100°C m.p.…”

Laser‐induced Deflagration for the Characterization of Energetic Materials

“…In particular, the replacement of gun igniter systems with lasers has been investigated by the U.S. Army Research Laboratory [5,6] since laser ignition has many advantages relative to percussive ignition, with the most significant being repeatability and the possibility to eliminate primers and igniters (thus decreasing the probability for accidental initiation). In addition, basic research on laser radiation interaction with energetic materials has been explored by many groups [7][8][9][10][11][12][13][14]. Generally, as the pulse length of the laser is increased, the energy threshold required for ignition decreases.…”

Modeling of combustion and ignition of solid-propellant ingredients

“…Calculated [6,11,23,92,102] burning rates of mono-and pseudo-propellants as function of pressure. 24 solid energetic materials, with emphasis on work performed in the Former Soviet Union, was provided by Strakouskiy et al [185].…”