Laser-Induced Ignition of RDX Monopropellant

The physical problem of concern is the ignition of a strand of RDX monopropellant induced by a continuous and radially uniform CO2 laser. The physiochemical processes involved are schematically illustrated in Fig. 5. The propellant and the ambient gas are initially at room temperature. Once the laser is activated, volumetric absorption of laser energy in the solid phase takes place, as shown in Fig. 5a. In the gas phase, only certain gaseous species, such as vapor RDX, absorbs a noticeable amount of laser energy at the wavelength of 

When a pure liquid layer is formed, the solid-liquid interface starts to move due to conductive and radiative heat transfer (Fig. 5c). 

In the liquid, thermal decomposition and subsequent reactions, as well as phase transition, take place, generating gas bubbles and forming a two-phase region. The propellant then undergoes a sequence of rapid evaporation at the surface (Fig. 5d). Ignition occurs if the heat flux is sufficiently large to initiate the subsequent self-accelerated exothermic reactions which result in substantial heat release (in the gas phase) and emission of light. A luminous flame is 

Steady-State Combustion of Nitramine/GAP Pseudo-Propellants 

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The theoretical model and numerical method outlined in the above sections were implemented to study steady-state combustion of nitramine monopropellants [33.34], laser-induced ignition of RDX [39,40], and steady-state combustion of nitramine/GAP pseudo-propellants [37-39]. The analyses were carried out over a broad range of operating conditions. Various important burning and ignition characteristics were investigated systematically, with emphasis placed on the detailed flame structure and the effect of the subsurface two-phase layer on propellant deflagration. 

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