Abstract: A method of analysing a spray of liquid from a nozzle comprises: receiving a fluorescent liquid composition comprising fluorophores of a first type and fluorophores of a second type, wherein the fluorophores of the first type are excitable by absorption of electromagnetic radiation in a first absorption wavelength band and are configured to emit electromagnetic radiation, following excitation, in a first emission wavelength band, and wherein the fluorophores of the second type are excitable by absorption of electromagnetic radiation in a second absorption wavelength band and are configured to emit electromagnetic radiation, following excitation, in a second emission wavelength band, wherein the first emission wavelength band overlaps with the second absorption wavelength band; ejecting the fluorescent liquid composition from the nozzle to generate a spray; projecting, within a sheet plane, a sheet of light through the spray, wherein the light comprises wavelengths within the first absorption wavelength band a

Abstract: A direct injection fuel system is shown for injecting hydrogen fuel into a gas turbine combustor. The fuel injection system includes a plurality of fuel injector blocks. Each fuel injector block includes a fuel admission duct having an inlet for receiving hydrogen fuel from a fuel supply, an outlet for delivering hydrogen fuel into the combustor and a central axis extending from said inlet to said outlet. Each fuel injector block also includes an air admission duct located around the periphery of the fuel admission duct, having an inlet for receiving air from a diffuser and an outlet for delivering air into the combustor for mixing with the hydrogen fuel.

Abstract: A direct fuel injection system (206) is shown for injecting hydrogen fuel into a gas turbine combustor, the fuel injection system comprising a plurality of fuel injector blocks (1202). Each fuel injector block includes one or more air admission ducts (1603) for receiving air from a diffuser and an air outlet for delivering air into a mixing zone for combustion with fuel. Each fuel injector block also includes a fuel admission duct or aperture having a fuel inlet for receiving fuel (F) from a manifold, and a fuel outlet for delivering fuel into the mixing zone.

Abstract: A direct injection fuel system is shown for injecting hydrogen fuel into a gas turbine combustor. The fuel injection system includes a plurality of fuel injector blocks. Each fuel injector block includes a fuel admission duct having an inlet for receiving hydrogen fuel from a fuel supply, an outlet for delivering hydrogen fuel into the combustor and a central axis extending from said inlet to said outlet. Each fuel injector block also includes an air admission duct located around the periphery of the fuel admission duct, having an inlet for receiving air from a diffuser and an outlet for delivering air into the combustor for mixing with the hydrogen fuel.