An apparatus is provided for modifying the geometry of at least one part of a turbine, which can include a shell assembly that includes an outer shell that is shaped to modify the shape of a pre-existing element of a turbine. The outer shell of the shell assembly can be composed of a fiber-reinforced polymeric material and can at least partially define an inner cavity. The outer shell can be bonded to a structure to modify the geometrical shape of that structure. Thereafter, a polymer casting can be injected into the inner cavity via at least one injection port attached to the shell assembly. In some embodiments, one or more stiffeners and/or a core can be positioned within the inner cavity to help improve the bonding of the polymer casting to the shell and/or improve a structural property of the apparatus.

An apparatus is provided for modifying the geometry of at least one part of a turbine, which can include a shell assembly that includes an outer shell that is shaped to modify the shape of a pre-existing element of a turbine. The outer shell of the shell assembly can be composed of a fiber-reinforced polymeric material and can at least partially define an inner cavity. The outer shell can be bonded to a structure to modify the geometrical shape of that structure. Thereafter, a polymer casting can be injected into the inner cavity via at least one injection port attached to the shell assembly. In some embodiments, one or more stiffeners and/or a core can be positioned within the inner cavity to help improve the bonding of the polymer casting to the shell and/or improve a structural property of the apparatus.

An oscillating water column (OWC) turbine and method of extracting energy therefrom is provided. The OWC turbine includes a shaft (101) rotatable about a central axis (103), and first and second ports (112, 114) disposed around the central axis. A flow passage (104) extends radially-inward from the ports and extends axially therebetween. Rotor blades (120) are coupled to the shaft, intersect the flow passage, and are offset from the central axis by a first distance. First guide vanes (116) intersect the flow passage and are disposed proximal the first port. The first guide vanes (116) include first and second stators (116a, b), the first stators (116a) being positioned between the first port (112) and the second stators (116b). Second guide vanes (118) intersect the flow passage and are disposed proximal the second port. The first and second guide vanes are offset from the central axis by a second distance that is greater than the first distance.

An oscillating water column (OWC) turbine and method of extracting energy therefrom is provided. The OWC turbine includes a shaft (101) rotatable about a central axis (103), and first and second ports (112, 114) disposed around the central axis. A flow passage (104) extends radially-inward from the ports and extends axially therebetween. Rotor blades (120) are coupled to the shaft, intersect the flow passage, and are offset from the central axis by a first distance. First guide vanes (116) intersect the flow passage and are disposed proximal the first port. The first guide vanes (116) include first and second stators (116a, b), the first stators (116a) being positioned between the first port (112) and the second stators (116b). Second guide vanes (118) intersect the flow passage and are disposed proximal the second port. The first and second guide vanes are offset from the central axis by a second distance that is greater than the first distance.

A hydraulic turbo machine has a runner that is impinged by water. A diffuser has a multiplicity of guide blades. The diffuser includes a regulating ring for rotating the guide blades. At least one hydraulic servomotor is connected to the regulating ring or to the runner blades. The servomotor has a multiple stage configuration. The housings of the stages are fixedly connected to one another and the pistons of the stages interact only in a part range of the entire adjusting range of the servomotor.

A wind turbine blade device includes a rotating unit including a blade module concentrically connected to a rotating shaft thereof and having a plurality of radially curved channels each having inlet and outlet ends. The inlet and outlet ends of the radially curved channels are configured to respectively permit flow of the flow body into and out thereof. An outer tube includes a tube body surrounding the rotating unit, and a plurality of rib plates provided in the tube body. The outlet end of each radially curved channel corresponds to one of the rib plates, and each radially curved channel forms an included angle with a corresponding rib plate such that the flow body flowing out of the outlet end can impact upon the corresponding rib plate.

A vane body of a guide vane includes a leading edge, and a trailing edge which is located closer to a runner than the leading edge, when located radially outside the runner. A projection extending in a direction from the trailing edge toward the leading edge is provided on an internal-diameter side blade face of the vane body, at least in any one of one side area of the internal-diameter side blade face and the other side area thereof in an axial direction of a guide vane rotation shaft, the internal-diameter side blade face being disposed on a side of the runner. The projection has a projection rear end of an arcuate shape, which projection rear end is formed to extend along a rotation trajectory which is drawn by the trailing edge when the vane body is rotated about the guide vane rotation shaft.

This method allows determining the operating point of a hydraulic machine in a considered operating range, such as turbine mode, and comprises steps that consist in a) determining two coordinates (N′11, T′11) of a first series of potential operating points of the hydraulic machine for the orientation affected to guide vanes of the machine, b) measuring the rotation speed of the machine, and c) determining the torque exerted by water flow on the machine. The method further includes steps consisting in d) calculating two coordinates (N11, T11) of a second series of potential operating points of the machine in function of the rotation speed (N) measured at step b) and the torque determined at step c), and e) deducing the two coordinates (N11_real, T11_real) of operating point that belongs both to the first and the second series in the said considered operating range of the machine.

A startup method of a Francis turbine according to an embodiment includes: a first rotation-speed increasing step in which a rotation speed of the runner is increased by opening the guide vane at a first opening; a second rotation-speed increasing step in which the increase in the rotation speed of the runner is accelerated by opening the guide vane at a second opening that is larger than the first opening after the first rotation-speed increasing step; and a rotation-speed regulating step in which the rotation speed of the runner is regulated to a rated rotation speed by opening the guide vane at a no-load opening after the second rotation-speed increasing step. The first opening is an opening that is half or less than the no-load opening.

A startup method of a Francis turbine according to an embodiment includes: a bypass-valve opening step of opening the bypass valve with the inlet valve closed; an inlet-valve opening step of opening the inlet valve after the bypass-valve opening step; and a first rotation-speed increasing step of increasing a rotation speed of the runner by opening the guide vane at an opening that is 50% or more of a maximum opening before a flow velocity of a swirling flow flowing around the runner reaches 90 m/sec.