Effect of Pressure on Hydrogen Enriched Natural Gas Jet Flames in Crossflow

Abstract

AbstractThe effect of pressure on hydrogen (H2) enriched natural gas jet flames in crossflow is experimentally investigated here. Simultaneously acquired high speed OH* chemiluminescence, OH planar laser induced fluorescence (PLIF), and stereoscopic particle image velocimetry are used to study flames at conditions typical of a gas turbine premixer, i.e. at elevated pressure, preheated crossflow, and in confinement. Two different H2 enrichment levels (40% and 20%, by volume) and pressures (10 bar and 15 bar) were studied here. Flames at the higher H2 enrichment level were found to be stabilized on the windward side, while the flames at the lower H2 enrichment were found to be stabilized only on the leeward side. Increased H2 enrichment was also associated with greater sootiness in the measured region. Jet centerline trajectories showed greater penetration for the higher H2 enrichment flames, which is in agreement with existing theories on the effect of heat release from a flame on crossflow entrainment. There were no significant changes observed in the mean OH* chemiluminescence, OH-PLIF, velocity fields, and velocity fluctuation fields with changes in pressure.