Abstract: A leakage mitigation system includes a leakage detection device having a canister configured to: (i) contain a first reactant and a second reactant and, (ii) based on a volume of liquid leaked from a tank, allow the first reactant and the second reactant to react with each other to produce a gas. A shut-off valve coupled to an inlet pipe of the tank is configured to actuate between an open condition and a closed condition. Further, a conduit extending between the leakage detection device and the shut-off valve allows flow of the gas from the leak detection device to the shut off valve. In order to mitigate the leakage of water, the shut-off valve is actuated between the open condition and the closed condition based on the pressure exerted thereon by the flow of the gas.

Abstract: A gas turbine engine (1) has a centrifugal compressor (4) and a radial turbine (14) mounted to a turbine shaft (2) for rotation with the shaft about the shaft axis Z. A number of combustion chambers (10) in the air/gas flow path between the compressor and the turbine are spaced circumferentially about the shaft axis. The combustion chambers (10) are elongate in the direction of air/gas flow and the longitudinal axis of each combustion chamber is skewed transversely relative to the axis Z of the turbine shaft. The combustion chambers (10) may be curved longitudinally about the shaft axis and may be aligned concentric about the axis. The engine may have a recuperator (8) radially outboard the compressor, the recuperator having radially directed flow passages through which air from the compressor is directed.

Abstract: A leakage mitigation system includes a leakage detection device having a canister configured to: (i) contain a first reactant and a second reactant and, (ii) based on a volume of liquid leaked from a tank, allow the first reactant and the second reactant to react with each other to produce a gas. A shut-off valve coupled to an inlet pipe of the tank is configured to actuate between an open condition and a closed condition. Further, a conduit extending between the leakage detection device and the shut-off valve allows flow of the gas from the leak detection device to the shut off valve. In order to mitigate the leakage of water, the shut-off valve is actuated between the open condition and the closed condition based on the pressure exerted thereon by the flow of the gas.

Abstract: A gas bearing system has at least one gas bearing (30, 32, 34) with a moving part and a static part and which can be operated in both aero-dynamic and aero-static modes. The system has a source (36) of pressurised gas fluidly connected with the bearing and a control system (134) for regulating the supply of pressurised gas to the bearing in dependence on the rotational speed of the moving part. The system has particular application in a turbocharger (1) where a flow of pressurised gas from the source is introduced into the bearing at the start-up and slow down phases of operation of the turbocharger, the flow being stopped, or reduced, when the turbocharger has reached normal operating speeds.

Abstract: A gas turbine engine (1) has a centrifugal compressor (4) and a radial turbine (14) mounted to a turbine shaft (2) for rotation with the shaft about the shaft axis Z. A number of combustion chambers (10) in the air/gas flow path between the compressor and the turbine are spaced circumferentially about the shaft axis. The combustion chambers (10) are elongate in the direction of air/gas flow and the longitudinal axis of each combustion chamber is skewed transversely relative to the axis Z of the turbine shaft. The combustion chambers (10) may be curved longitudinally about the shaft axis and may be aligned concentric about the axis. The engine may have a recuperator (8) radially outboard the compressor, the recuperator having radially directed flow passages through which air from the compressor is directed.

Abstract: A gas bearing system has at least one gas bearing (30, 32, 34) with a moving part and a static part and which can be operated in both aero-dynamic and aero-static modes. The system has a source (36) of pressurized gas fluidly connected with the bearing and a control system (134) for regulating the supply of pressurized gas to the bearing in dependence on the rotational speed of the moving part. The system has particular application in a turbocharger (1) where a flow of pressurized gas from the source is introduced into the bearing at the start-up and slow down phases of operation of the turbocharger, the flow being stopped, or reduced, when the turbocharger has reached normal operating speeds.

Abstract: A gas bearing system has at least one gas bearing (30, 32, 34) with a moving part and a static part and which can be operated in both aero-dynamic and aero-static modes. The system has a source (36) of pressurised gas fluidly connected with the bearing and a control system (134) for regulating the supply of pressurised gas to the bearing in dependence on the rotational speed of the moving part. The system has particular application in a turbocharger (1) where a flow of pressurised gas from the source is introduced into the bearing at the start-up and slow down phases of operation of the turbocharger, the flow being stopped, or reduced, when the turbocharger has reached normal operating speeds.

Abstract: The present invention provides a lithographic process for producing high aspect ratio parts from an epoxy-type negative photoresist comprising the steps of: (i) irradiating a prebaked masked epoxy-type negative photoresist on a substrate with light at a total energy density of from 18,000 to 35,000 mJ/cm2, (ii) post-baking the exposed photoresist at elevated temperature, and (iii) developing the exposed photoresist in a solvent, wherein no more than 15% of the energy density is contributed by light having a wavelength of 400 nm or less. The invention also discloses a reciprocating microengine (10) comprising a cylinder (14), piston (12) and crankshaft made by the process.

Abstract: The present invention provides a lithographic process for producing high aspect ratio parts from an epoxy-type negative photoresist comprising the steps of: (i) irradiating a prebaked masked epoxy-type negative photoresist on a substrate with light at a total energy density of from 18,000 to 35,000 mJ/cm2, (ii) post-baking the exposed photoresist at elevated temperature, and (iii) developing the exposed photoresist in a solvent, wherein no more than 15% of the energy density is contributed by light having a wavelength of 400 nm or less. The invention also discloses a reciprocating microengine (10) comprising a cylinder (14), piston (12) and crankshaft made by the process.