Modeling of high energy laser ignition of energetic materials

Abstract

We present a model for simulating high energy laser heating and ignition of confined energetic materials. The model considers the effect of irradiating a steel plate with long laser pulses and continuous lasers of several kilowatts and the thermal response of well-characterized high explosives for ignition. Since there is enough time for the thermal wave to propagate into the target and to create a region of hot spot in the high explosives, electron thermal diffusion of ultrashort (femto- and picosecond) lasing is ignored; instead, heat diffusion of absorbed laser energy in the solid target is modeled with thermal decomposition kinetic models of high explosives. Numerically simulated pulsed-laser heating of solid target and thermal explosion of cyclotrimethylenetrinitramine, triaminotrinitrobenzene, and octahydrotetranitrotetrazine are compared to experimental results. The experimental and numerical results are in good agreement.

Thermal management of GaInNAs/GaAs VECSELs

“…However, such values are unrealistic. Generally, in semi− conductor lasers and different electronic devices, h from the 0−500 W/(m 2 K) range is assumed [12][13][14][15]. Then no change in the maximal temperature increase has been noticed (see Fig.…”

Sensitivity and Performance of Energetic Materials

“…The Al particle composites showed significantly reducedi gnition times that varied from 12 ms up to 6s,r espectively,f or nanometer scale particle size compared with the micrometer scale Al particle composites. Lee et al have rigged up am odelf or simulating high energy laser heatinga nd ignitiono fc onfined EMs [124]. The modelc onsiders the effect of irradiatingasteel plate with long laser pulsesa nd continuous lasers of several kilowatts and also the thermal response of well-characterized EMs for ignition; the final model was verified on RDX, HMX, and TATB [124].B hattacharya et al [125] used ultraviolet lasers at different wavelengths, such as 226, 236, and 193 nm, to prepare the exciteds tates of nitromethane (NM), dimethylnitramine (DMNA), and isopropyl nitrate (IPN) which are used as model molecules for CÀNO 2 ,N À NO 2 ,a nd OÀNO 2 activem oieties, respectively.T he major decompositionp athway of electronic excitationa t1 93 nm of NM and IPN involves fissiono ft he XÀNO 2 bond to form an electronically excited NO 2 product, which further dissociates to generate NO.…”

“…Lee et al have rigged up am odelf or simulating high energy laser heatinga nd ignitiono fc onfined EMs [124]. The modelc onsiders the effect of irradiatingasteel plate with long laser pulsesa nd continuous lasers of several kilowatts and also the thermal response of well-characterized EMs for ignition; the final model was verified on RDX, HMX, and TATB [124].B hattacharya et al [125] used ultraviolet lasers at different wavelengths, such as 226, 236, and 193 nm, to prepare the exciteds tates of nitromethane (NM), dimethylnitramine (DMNA), and isopropyl nitrate (IPN) which are used as model molecules for CÀNO 2 ,N À NO 2 ,a nd OÀNO 2 activem oieties, respectively.T he major decompositionp athway of electronic excitationa t1 93 nm of NM and IPN involves fissiono ft he XÀNO 2 bond to form an electronically excited NO 2 product, which further dissociates to generate NO. The production of NO molecules from electronically excited DMNAi sp roposed to go through an itro-nitrite isomerization pathway.A bdulazeem et al [126] have dealt theoretically with the behavior of b-lead azide when heated by continuous and pulsed laser;i th as been arguedt hat this azidei nitiationw ith low energy laser is thermali no rigin.C iviš et al [127] have studied 2,2-dinitroethylene-1,1-diamine (FOX-7) under the influence of ac ombination of laser-induced breakdown spectroscopy (LIBS) and selected ion flow tube mass spectrometry (SIFT-MS) and they tried to formulate the chemical mechanism of the FOX-7 molecule fission.…”

Effect of Decomposition of CuO Film on Ignition of Organic Explosives by a Laser Pulse

“…Interest in the ignition of energetic materials by the luminous flux has continued to this day. The emergence of experimental and theoretical work is associated with the use of laser systems for EM initiation, as well as studying the mechanism of EM ignition for the purpose of directional control of the EM threshold initiation energy by laser radiation [1][2][3][4][5][6][7][8].…”