Investigation of a Premixed Gas Turbine Combustor Central Body Burner Using OH Planar Laser Induced Fluorescence at Elevated Pressures Available to Purchase

Experiments were performed on the central body rich-pilot-lean (RPL) burner of a Siemens Industrial Turbomachinary 4th generation DLE combustor to observe the combustion changes that may occur when using fuels other than natural gas. Measurements were taken of temperatures at multiple points along the RPL body while hydroxyl (OH) radical distribution extending from the dump plane of the burner was imaged by planar laser induced fluorescence (PLIF). The RPL burner was run using four fuels; methane, a generic syngas (67.5% H₂, 22.5% CO and 10% CH₄) and dilutions of these with nitrogen to a Wobbe index of 15 MJ/m³. Each of the fuels was operated at several equivalence ratios ranging from ϕ = 0.80 to ϕ = 1.80, for combustion pressures of 3, 6 and 9 bar. It was found that the flame position in the RPL, determined from temperature measurement at the thermocouple positions, was dependent on the fuel, equivalence ratio and to a lesser extent pressure. A link was established between the OH distribution in the post burner region and RPL temperature profiles based on the expected flame behavior inside the RPL. For all measurement points some combustion occurred within the burner volume, indicated by thermocouples at the burner exit.