Combustion Stability and Emissions in a Lean Premixed Industrial Gas Turbine Burner Due to Changes in the Fuel Profile

Abstract

This paper deals with an experimental investigation of dry low emission (DLE) burners for industrial gas turbines. Changes in the fuel profile, pressure drop over the burner and external pilot flame stabilization have been investigated regarding combustion stability and emissions. This has been achieved by parallel experimental work in a water rig and a newly commissioned atmospheric combustion test rig. Some verifying tests in a high pressure rig were also conducted. The work in the water rig has been directed towards evaluating different fuel profiles at the burner exit due to changes in the fuel outlet geometry. Variations of the fuel outlet geometry were achieved by altering the effective area of the hardware configuration of the fuel outlet ports or by moving or adding fuel outlet ports. A few of the tested configurations in the water rig was chosen for further evaluation by atmospheric combustion tests with respect to combustion stability and emissions. A more general study on combustion stability and emissions was also performed for different burners, burner configurations and variations in pressure drop over the burner. The pressure drop over the burner in the test corresponds very well to the pressure drop measured over a single burner in an annular combustion chamber of an industrial gas turbine at different loads. The combustion was monitored by a high speed video camera equipped with an image intensifier. Simultaneously the dynamic pressure was measured by a piezoelectric pressure transducer, making it possible to know when each image was taken relative to the pressure. Results for different hardware configurations will be shown considering the frequency response from the flame and the dynamic pressure as well as the characteristic combustion instability close to lean blowout.

Investigation of Hydrogen Enriched Natural Gas Flames in a SGT-700/800 Burner Using OH PLIF and Chemiluminescence Imaging

“…In all experiments, the DLE burner was mounted in an atmos pheric combustion test rig that has also been used in previous stud ies [19][20][21]. The combustion chamber consists of a casing and a liner that is cooled convectively and has a single can configuration, see Fig.…”

“…Emission probes, pressure transducers, and thermocou ples is used for monitoring and measuring emissions, the dynamic pressure and temperatures at different positions in the combustion chamber, see Ref. [19] for further details.…”