Scenarios of combustion of plane hydrogen microjets at sub- and supersonic velocities

Abstract

Experimental data on diffusion combustion of plane hydrogen microjets emanating from a slotted micronozzle at subsonic and supersonic velocities are reported. Four scenarios of diffusion combustion of the hydrogen microjets are presented. As is found, the stabilization of subsonic combustion of the hydrogen microjet is related to the origination of a “bottle-neck” configuration of flame while in supersonic conditions the flow pattern is dominated by supersonic cells. Hysteresis of the diffusion combustion of plane hydrogen microjet is found depending on its ignition far from or close to the nozzle exit and velocity variation.