COMBUSTION STAGING SYSTEM

摘要

A combustion staging system for fuel injectors of a multi-stage combustor of a gas turbine engine has pilot and mains fuel manifolds distributing fuel to the injectors. A splitting unit splits a fuel flow and sends portions of the flow to pilot and mains fuel manifolds to perform staging control of the combustor. The splitting unit can deselect the mains manifold so that there is no flow into the combustor from the mains manifold. A cooling flow recirculation line provides a cooling flow of fuel to the mains manifold when that manifold is deselected so that the mains manifold remains primed with relatively cool fuel. A return section collects the cooling flow from the mains manifold. One or more fuel pressure sensors detect pressure of the cooling flow on the recirculation line. A control arrangement closes off the recirculation line when the pressure sensor(s) indicates failure of the cooling flow.

主权项

1. A combustion staging system for fuel injectors of a multi-stage combustor of a gas turbine engine, the system having:
pilot and mains fuel manifolds respectively distributing fuel to pilot and mains stages of the injectors; a splitting unit which controllably splits a metered fuel flow and sends respective portions of the metered flow to the pilot and mains fuel manifolds to perform staging control of the combustor, the splitting unit being able to deselect the mains manifold so that there is no flow into the combustor from the mains manifold; a cooling flow recirculation line having a delivery section arranged to provide a cooling flow of fuel to the mains manifold when that manifold is deselected so that the deselected mains manifold remains primed with relatively cool fuel, and a return section arranged to collect the cooling flow from the mains manifold; wherein the system further has: one or more fuel pressure sensors which detect the pressure of the cooling flow on the recirculation line; and a control arrangement which is adapted to close off the recirculation line when the pressure sensor(s) indicates a failure of the cooling flow.