Apparatus and method for a combustor

摘要

A combustor includes an end cover and a combustion chamber downstream of the end cover. The combustor further includes nozzles disposed radially in the end cover and a shroud surrounding at least one of the nozzles and extending downstream into the combustion chamber. The shroud includes an inner wall surface and an outer wall surface. A method for operating a combustor includes flowing compressed working fluid through nozzles into a combustion chamber, flowing fuel through each nozzle in a first subset of the nozzles into the combustion chamber, and igniting the fuel from each nozzle in the first subset of nozzles in the combustion chamber. In addition, the method includes extending into the combustion chamber a separate shroud around each nozzle in a second subset of the nozzles and isolating fuel to each nozzle in the second subset of nozzles.