Abstract: A combustion chamber system has pilot and main fuel manifolds, and pilot and main fuel nozzles. Each pilot nozzle is connected to the pilot manifold. Each main nozzle is connected to the main manifold. A greater total amount of fuel is supplied to the pilot nozzles than to the main nozzles. A greater amount of fuel is supplied to pilot nozzles at, or in, a first region of the combustion chamber than to pilot fuel nozzles at, or in, a second region. A greater amount of fuel is supplied to the main nozzles at, or in, the first region than to the main nozzles at, or in, the second to improve combustion efficiency, weak extinction and relight of the combustion chamber in a first mode of operation. A greater total amount of fuel is supplied to the main nozzles than to the pilot nozzles in a second mode of operation.

Abstract: Combustion chamber includes a primary stage fuel burner to supply fuel into a primary combustion zone and secondary stage fuel burner supplies fuel into a secondary combustion zone. A sensor is positioned downstream from combustion chamber measuring concentration of one or more compounds. The sensor sends measurements of the concentration of compounds to a processor. The processor compares the measured concentration of the compound with a first threshold value and a second threshold value. The processor supplies more fuel to the primary stage fuel burner if the measured concentration is higher than the first threshold value, supplies more fuel to the secondary stage fuel burner if the measured concentration is higher than the second threshold value, maintaining fuel supply to the primary and secondary stage fuel burners if the measured concentration is lower than the first threshold value and lower than the second threshold value.

Abstract: A fuel supply system for fuel injectors of a multi-stage combustor of a gas turbine engine. The fuel supply system includes a metering and splitting arrangement which receives a total fuel flow and controllably meters and splits the received total fuel flow into metered pilot and mains flows. The fuel supply system further includes a de-priming sub-system, one or more fuel lines of a mains fuel distribution pipework being fluidly connected to the mains fuel discharge orifices and extending to the de-priming sub-system, and the de-priming sub-system being configured to remove the mains fuel from the injectors. A re-priming sub-system, the one or more fuel lines of the mains fuel distribution pipework also extending to the re-priming sub-system, and the re-priming sub-system being configured to refill the injectors with mains fuel through the one or more fuel lines when the mains distribution pipework is selected for pilot and mains operation.

Abstract: A combustion chamber system has pilot and main fuel manifolds, and pilot and main fuel nozzles. Each pilot nozzle is connected to the pilot manifold. Each main nozzle is connected to the main manifold. A greater total amount of fuel is supplied to the pilot nozzles than to the main nozzles. A greater amount of fuel is supplied to pilot nozzles at, or in, a first region of the combustion chamber than to pilot fuel nozzles at, or in, a second region. A greater amount of fuel is supplied to the main nozzles at, or in, the first region than to the main nozzles at, or in, the second to improve combustion efficiency, weak extinction and relight of the combustion chamber in a first mode of operation. A greater total amount of fuel is supplied to the main nozzles than to the pilot nozzles in a second mode of operation.

Abstract: Combustion chamber includes a primary stage fuel burner to supply fuel into a primary combustion zone and secondary stage fuel burner supplies fuel into a secondary combustion zone. A sensor is positioned downstream from combustion chamber measuring concentration of one or more compounds. The sensor sends measurements of the concentration of compounds to a processor. The processor compares the measured concentration of the compound with a first threshold value and a second threshold value. The processor supplies more fuel to the primary stage fuel burner if the measured concentration is higher than the first threshold value, supplies more fuel to the secondary stage fuel burner if the measured concentration is higher than the second threshold value, maintaining fuel supply to the primary and secondary stage fuel burners if the measured concentration is lower than the first threshold value and lower than the second threshold value.

Abstract: A fuel injector includes pilot and main fuel injectors. The pilot fuel injector includes at least one pilot air swirler and the main fuel injector includes a main air blast fuel injector located between inner main and outer main air swirlers. A first air splitter is located between the pilot and inner main air swirlers and a second air splitter is located between the pilot and inner main air swirlers. The first air splitter has a downstream portion converging to a downstream end. The second air splitter has a downstream portion diverging to a downstream end. The second air splitter downstream end is downstream of the first air splitter downstream end and the ratio of the distance from the first air splitter downstream end to the second air splitter downstream end to the diameter of the second air splitter downstream end is in the range of 0.22 to 0.30.

Abstract: A combustion chamber for a gas turbine engine comprising at least one Helmholtz resonator having a resonator cavity and a resonator neck in flow communication with the interior of the combustion chamber. The cavity extends around at least part of the neck and is spaced apart therefrom to define a cooling chamber therebetween. The cooling chamber allows the neck and the cavity to be cooled with a flow of cooling air. The sunken neck allows the resonator to be located within enclosures with minimal volume without compromising on the damping properties afforded.

Abstract: A combustor wall of a gas turbine engine is provided with an acoustic damper component. The component has a first metering passage, a first damping chamber, a first damping passage, a second damping chamber and a second damping passage. Air flows through the damper to be ejected into the combustion chamber from the second damping passage at a selected velocity and volumetric flow. The flow being sufficient to damp instabilities from the combustion process.

Abstract: A combustion chamber suitable for a gas turbine engine is provided with at least one Helmholtz resonator having a resonator cavity and a resonator neck in flow communication with the chamber interior. The resonator neck is provided with at least cooling holes extending through its wall for improved damping and cooling, at least one of the holes is directed towards the resonator cavity.

Abstract: A combustion chamber for a gas turbine engine comprising at least one Helmholtz resonator having a resonator cavity and a resonator neck in flow communication with the interior of the combustion chamber. The cavity extends around at least part of the neck and is spaced apart therefrom to define a cooling chamber therebetween. The cooling chamber allows the neck and the cavity to be cooled with a flow of cooling air. The sunken neck allows the resonator to be located within enclosures with minimal volume without compromising on the damping properties afforded.

Abstract: A method of non-thermal annealing of a silicon wafer comprising irradiating a doped silicon wafer with electromagnetic radiation in a wavelength or frequency range coinciding with lattice phonon frequencies of the doped semiconductor material. The wafer is annealed in an apparatus including a cavity and a radiation source of a wavelength ranging from 10-25 ?m and more particularly 15-18 ?m, or a frequency ranging from 12-30 THz and more particularly 16.5-20 THz.

Abstract: A combustor wall of a gas turbine engine is provided with an acoustic damper component. The component has a first metering passage, a first damping chamber, a first damping passage, a second damping chamber and a second damping passage. Air flows through the damper to be ejected into the combustion chamber from the second damping passage at a selected velocity and volumetric flow. The flow being sufficient to damp instabilities from the combustion process.

Abstract: A combustion chamber suitable for a gas turbine engine is provided with at least one Helmholtz resonator having a resonator cavity and a resonator neck in flow communication with the chamber interior. The resonator neck is provided with at least cooling holes extending through its wall for improved damping and cooling, at least one of the holes is directed towards the resonator cavity.

Abstract: A method of non-thermal annealing of a silicon wafer comprising irradiating a doped silicon wafer with electromagnetic radiation in a wavelength or frequency range coinciding with lattice phonon frequencies of the doped semiconductor material. The wafer is annealed in an apparatus including a cavity and a radiation source of a wavelength ranging from 10-25 ?m and more particularly 15-18 ?m, or a frequency ranging from 12-30 THz and more particularly 16.5-20 THz.