EFFECTS OF BACK-PRESSURE IN A LEAN BLOWOUT RESEARCH COMBUSTOR

Experimental information is presented on the effects of back-pressure on flame-holding in a gaseous fuel research combustor. Data for wall t emperatures and static pressures are used to infer behavior of the maj or recirculation zones, as a supplement to some velocity and temperatu re profile measurements using LDV and CARS systems. Observations of fl ame behavior are also included. Lean blowout is improved by exit block age, with strongest sensitivity at high combustor loadings. It is conc luded that exit blockage exerts its influence through effects on the j et and recirculation zone shear layers.