关键词: 超声速燃烧, 预燃室, 波瓣掺混器, 流向涡掺混, 双燃式冲压发动机

Abstract: To investigate the principle and parameters of the flying Mach number 5-7 hydrocarbon fueled dual-combustor scramjet engine, the authors performed the experimental studies of both cold flow field mixing and combustion on a direct-connected combined supersonic-combustor with a flame holding torch formed by a small pilot burner and a streamwise vortices generator. Three pilot burners and one supersonic combustor were taken into the experiment of cold through flow, fuel injection and ignition under the condition of combustor inlet Mach number 2.5, total pressure 15atm/10atm, total temperature 285K. The experiment and CFD calculation indicate four results. The main flow in the supersonic combustor keeps supersonic, though the oblique shock train slightly moved while dual-combustor ignited. There are four kinds of vortices phenomena which enhanced the mixing between sub- and super-sonic flows. The combination of a triple-shock inlet and a small volumetric-heat-intensity combustor with the lobed mixer could realize a stable torch flame as a stabilized holder of the supersonic combustion. In this combustor, the second area of flame has been found in the original cold flow region of subsonic and low-supersonic flows within the supersonic combustor, without the destruction of the supersonic flow state of the upper flow-layers.

Key words: supersonic combustion, pilot burner, lobed mixer, streamwise vortices mixing, dual-combustor ramjet