A fluid power generation device is configured to provide electric power generation using fluid action, and comprises multiple power generation mechanisms. Each power generation mechanism comprises: a casing that allows a fluid to pass through its internal space; and a power generation unit arranged within the casing, and configured to perform electric power generation using the fluid action. The casing is configured to generate vortexes in the vicinity of its fluid outlet. The multiple casings are arranged with spaces as intervals between them. Each casing generates vortexes in the vicinity of its fluid outlet. Furthermore, such an arrangement provides an interaction effect between the vortexes generated in the vicinity of the fluid outlets of the multipole casings arranged with the spaces as intervals between them. This provides a synergistic effect for accelerating the inner flow based on the interaction between the power generation mechanisms.

Methods and systems are provided for mitigating noise generated by a compressor operating at low flow rates. A swirl device with two concentric flow passages upstream of the compressor directs intake air flow to the compressor through two different flow paths, depending on air flow rates. Angled swirl vanes at an outlet of the swirl device pre-whirl the air flowing to the compressor to reduce noise generation at low air flow rates.

A method of retrofitting vortex generators on a wind turbine blade is disclosed, the wind turbine blade being mounted on a wind turbine hub and extending in a longitudinal direction and having a tip end and a root end, the wind turbine blade further comprising a profiled contour including a pressure side and a suction side, as well as a leading edge and a trailing edge with a chord having a chord length extending there between, the profiled contour, when being impacted by an incident airflow, generating a lift. The method comprises identifying a separation line on the suction side of the wind turbine blade, and mounting one or more vortex panels including a first vortex panel comprising at least one vortex generator on the suction side of the wind turbine blade between the separation line and the leading edge of the wind turbine blade.

A vortex generator for a wind turbine blade includes: a platform portion to be fixed to a surface of the wind turbine blade; and at least one fin erected on the platform portion. The platform portion includes marks disposed on a pair of opposite positions in an outer edge region of the platform portion and indicating orientation of the vortex generator.

A method of mounting a vortex generator to a wind turbine blade includes: a step of specifying positions of at least two reference points at different coordinates in a blade spanwise direction of the wind turbine blade on the wind turbine blade; and a step of adjusting a mounting direction of the vortex generator and mounting the vortex generator to the wind turbine blade, with reference to a line connecting the reference points. The step of specifying the positions of the reference points comprises specifying the position of each of the reference points on the basis of: a length along a surface of the wind turbine blade in a chordwise direction from a trailing edge of the wind turbine blade or from a blade spanwise directional line extending along the blade spanwise direction on the surface of the wind turbine blade; and a distance in the blade spanwise direction from a blade root or from a blade tip of the wind turbine blade.

A tip structure may be arranged for example on a rotor blade (12) of a HAWT (10). The tip structure comprises a pressure side structure (50) arranged on a pressure side (43) of the blade, and a suction side structure (60) arranged on a suction side (44) of the blade (12). The pressure side and suction side structures (50, 60) have different pitch angles (αP, αS) so that the chord (CP2) of the pressure side structure (50) extends forwardly in the direction of motion (D) and relatively more radially outwardly away from the blade root, or less radially inwardly towards the blade root, than the chord (CS2) of the suction side structure (60), defining a relative twist angle (αT) between the two structures (50, 60).

An accelerated and/or redirected flow arrangement, optimally serving as a wildlife and/or debris excluder (WDE), is used in combination with a turbine-like device having an inlet end and an outlet end for fluid flowing therethrough, e.g., a hydro-turbine. The arrangement includes at least a forward part designed to be placed in front of a fluid inlet of a turbine-like device and configured to produce at least one of the following effects on the fluid: (a) imparting a re-direction of the fluid; and/or (b) accelerating the flow velocity of the fluid, as it flows through the forward part. Turbine-like devices having both a forward part and a rearward part of flow arrangement are disclosed, as well as a method of enhancing turbine performance.

A wind turbine blade (10, 610) for a rotor of a wind turbine (2) having a substantially horizontal rotor shaft is described. A surface mounted device (70, 70′, 170, 270, 370, 470, 570, 670, 770) is attached to a surface of the wind turbine blade (10). The surface mounted device (70, 70′, 170, 270, 370, 470, 570, 670, 770) is attached to the surface of the wind turbine blade (10, 610) via at least a first attachment part (77, 77′), which is connected to a part of the surface mounted device (70, 70′, 170, 270, 370, 470, 570, 670, 770). The attachment part (77, 77′) comprises a flexible housing (80, 80′, 680, 780) that forms a cavity (81, 81′, 681, 781) between at least the housing (80, 80′, 680, 780) and the surface of the wind turbine blade (10, 610). The cavity (80, 80′, 680, 780) is filled with an adhesive that provides an adhesive bonding to the surface of the wind turbine blade (10, 610).

A wind turbine blade vortex generator unit and a method for installing it, where a wind turbine blade has at least one series of vortex generator units formed of fins extending substantially perpendicular to the surface of the airfoil and substantially in a direction from the leading edge towards the trailing edge of the wind turbine blade. The vortex generator units each comprises a fin connected to an outer side of the fin base, and where the fin is delta shaped tapering from a trailing edge towards a leading edge and where each of the vortex generator units has a layer of adhesive on an inner side of the base that extends to an outermost periphery of the base. The vortex generator unit has exactly one fin, and the base has an airfoil shaped periphery with a rounded leading edge and a trailing edge.

A method for manufacturing a tower structure of a wind turbine includes printing, via an additive printing device, the tower structure of the wind turbine of a cementitious material. The method also includes printing, via the additive printing device, one or more additional airflow modifying features on an outer surface the tower structure of the wind turbine so as to reduce and/or prevent vortex shedding, excitation, and/or drag of the tower structure. Further, the method includes curing the cementitious material so as to form the tower structure.