Laser-Induced Breakdown and Detonation in Particle-Laden Systems

Abstract

Simulation of the interaction of a laser pulse with gas-droplet and gas-particle mixtures plays an important role in environmental and engineering applications. The injection of liquid droplets or metal particle causes optical breakdown on the individual droplet or particle and leads to a drop of the detonation minimum pulse energy of the mixture. Mathematical models of various stages of the optical breakdown are developed and applied to the analysis of laser-induced breakdown in particle-laden systems. The numerical calculations are based on an in-house computer code using the finite-volume method and high-resolution scheme. The threshold of optical breakdown and its dependence on contributing factors (droplet radius, location of droplet, total energy and time of laser pulse, radius of laser spot) has been studied. Minimum pulse energy of detonation was computed in the hydrogen-oxygen mixture with metal particles and liquid droplets.

Multi-point ignition of air/fuel mixture by the initiated subcritical streamer discharge

“…The main problem of the development of ignition systems is the need to improve the reliability of ignition without significantly increasing the energy consumption for the ignition process [10]. The use of microwave radiation, high-power lasers and corona discharges seems to be unattractive, due to the low efficiency of such systems [19,20]. Nevertheless, the volumetric plasma ignition of the fuel mixture has undeniable advantages [21][22][23], allowing it to be used not only in detonation engines, but also in traditional internal combustion engines for boosting the speed or reducing nitrogen oxide emissions due to significant increasing the combustion rate, as well as for stabilizing combustion in a supersonic flow [24].…”

“…For the case of ignition by a laser discharge, the values of the minimum ignition energy are higher than those for ignition by a spark discharge, and significantly depend on the duration, energy, wavelength of the laser pulse [19,33]. Potential advantages of using combustion stimulated by non-equilibrium plasma of a pulsed discharge in various applications are discussed in [34,35].…”