| 摘要 |
In a gas turbine having a plurality of combustors, each having an annular array of outer fuel nozzles arranged about a center axis, an improved construction is provided wherein each combustor has a center nozzle located on the center axis. Various methods of operating the improved combustor are also disclosed. For example, one method of operating a combustor for a gas turbine wherein the combustor has a plurality of fuel nozzles in an annular array arranged about a center axis and has a center nozzle located on the center axis, and wherein the annular array is supplied with fuel from at least one pre-mix fuel manifold, and further wherein the center nozzle is supplied with fuel from a center nozzle pre-mix fuel manifold includes the steps of: a) at ignition, supplying the center nozzle with fuel from the center nozzle pre-mix fuel manifold and two of the outer fuel nozzles in line with cross-fire tubes with fuel from at least one pre-mix fuel manifold; b) after detecting cross-fire with flame detectors, turning off fuel to the outer two cross-fire nozzles, supplying all fuel to the center nozzle, and accelerating through FSNL to a part load by increasing fuel flow to the center nozzle; c) at the part load, begin transferring some pre-mix fuel away from the center nozzle and staging it to the outer fuel nozzles in the following sequence as total fuel flow is increased: 1) center nozzle+two cross-fire nozzles, 2) center nozzle+non-cross-fire nozzles, 3) all outer fuel nozzles in annular array (no center nozzle), and 4) center nozzle+all outer fuel nozzles.
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