Abstract: A power production system is provided that includes: a hydraulic turbine, installable in a penstock and being rotatable in a first rotation direction by effect of a flow of fluid flowing in the penstock in a downward direction; an energy converter group; an accumulator; a control unit, configured to operate the system in a power generation mode, in which the energy converter group receives an input mechanical power from the hydraulic turbine rotating in the first rotation direction, generates an output electric power and supplies said output electrical power to an external grid and/or to the accumulator, and in a downward pushing mode, in which the energy converter group absorbs an input electrical power from the accumulator and generates an output mechanical power to move the hydraulic turbine.

Abstract: A connecting duct for providing a fluid pathway between an outlet of a low pressure compressor and an inlet of a high pressure compressor is provided. The connecting duct includes a main body that defines a fluid pathway adapted to direct a flow of fluid between a main body inlet and a main body outlet. The main body also includes a diffusing section that decreases a velocity of the flow of fluid. A flow de-swirling section is disposed between the diffusing section and the outlet of the main body. The flow de-swirling section straightens the flow of fluid.

Abstract: A hydraulic turbine has a gas distribution manifold mounted to an inside wall of a draft tube downstream from a turbine runner. The gas distribution manifold extends at least substantially around the first inside wall of the draft tube. The gas distribution manifold has a plurality of gas outlet ports for discharging oxygen into the water as the oxygen containing gas passes there around. An oxygen containing gas supply extends along a person access passageway and through the wall of the draft tube into the gas distribution manifold adjacent a man hole door.

Abstract: An actuator having a body defining an internal cavity and a gland disposed within the cavity, the gland being secured against movement relative to the actuator body in a direction along the internal cavity by a securing element located in an opening of which respective parts are defined by the actuator body and the gland, and which allows insertion of the securing element into the opening along a substantially linear path.

Abstract: A draft tube for a reaction turbine is formed of two gutter-shaped members of semi-circular transverse cross-section which are secured along their edges to a dividing plate. Flat guide plates are secured in the gutters to permit flattening the stream of water during its passage through the curved part of the draft tube.

Abstract: Hydraulic turbo machines are provided with air admitting and inducing arrangements in the draft tube, below the runner. This permits the admission of air in flow stabilizing relation, particularly at partial loads so as to diminish noise, vibration and cavitation, and to stabilize machine operation.

Abstract: A hydraulic turbo-machine such as a Francis turbine has a draft tube with air admission provision, to stabilize flow. A plurality of air boxes are provided having a long upstream surface and a short downstream surface to provide an inductive effect with the flow of water downwardly thereover. A non-return valve at the box downstream face substantially precludes the ingress of water within the box during conditions of disturbed flow, so that the breathing capability of the box is optimized.

Abstract: An arrangement for introducing air into the draft tube of turbo-hydraulic machines, in order to promote smooth running at part-load and to facilitate the achievement of full load, relies upon the use of a protective plate in covering relation with the air admission opening and cooperating with the structure located within the draft tube to act as an air eductor, in the manner of a venturi.

Abstract: A hydraulic turbine having means for admitting air to the turbine draft tube. An annular air chamber about the draft tube has a plurality of circumferentially spaced openings into the interior of the draft tube. The pressure of the air in the air chamber is maintained below the maximum pressure of the water in the draft tube and above the minimum pressure of the water in the draft tube. This results in air entering the draft tube only at the areas of lowest water pressure and water entering the air chamber at areas of highest water pressure.