A vortex suppression device (10) for a fluid flowing along a pathway (A-E), including: an elongate body with an outer surface having an elongate leading section and an elongate trailing section along the length of the elongate body, in relation to a direction of fluid flow (A-E) when the device is located in the pathway, the elongate body having at least one channel (24a-24d, 26a, 26b) which extends from the elongate leading section to the elongate trailing section of the elongate body, the channel (24a-24d, 26a, 26b) being configured so that in use, when the device is in the pathway, the channel (24a-24d, 26a, 26b) allows fluid flow (J) towards the trailing section that disrupts the formation of vortices (D).

A vortex suppression device (10) for a fluid flowing along a pathway (A-E), including: an elongate body with an outer surface having an elongate leading section and an elongate trailing section along the length of the elongate body, in relation to a direction of fluid flow (A-E) when the device is located in the pathway, the elongate body having at least one channel (24a-24d, 26a, 26b) which extends from the elongate leading section to the elongate trailing section of the elongate body, the channel (24a-24d, 26a, 26b) being configured so that in use, when the device is in the pathway, the channel (24a-24d, 26a, 26b) allows fluid flow (J) towards the trailing section that disrupts the formation of vortices (D).

A system includes a surface having a fluid flowing over the surface. The fluid includes a flow regime having a streamwise length scale greater than about 100 times η and less than about 100,000 times η, where η is a viscous length scale of the flow regime, and a convective time scale greater than about 10η′ and less than about 10,000η′, where η′ is a viscous time scale of the flow regime. The system includes a controller that causes at least one of motion the surface to modify fluid flow in the flow regime based on the streamwise length scale and the convective time scale or motion of the flow regime based on the streamwise length scale and the convective time scale.

A system includes a surface having a fluid flowing over the surface. The fluid includes a flow regime having a streamwise length scale greater than about 100 times η and less than about 100,000 times η, where η is a viscous length scale of the flow regime, and a convective time scale greater than about 10η′ and less than about 10,000η′, where η′ is a viscous time scale of the flow regime. The system includes a controller that causes at least one of motion the surface to modify fluid flow in the flow regime based on the streamwise length scale and the convective time scale or motion of the flow regime based on the streamwise length scale and the convective time scale.

Described herein is a process for producing a structured article (A1M1) in which a material (M1) including at least one micro- and/or nanostructured surface (SU1) containing a plurality of micro-scale and/or nano-scale surface elements is covered with an at least partially cured coating layer (C2) to provide a composite (M1C2), said composite (M1C2) is attached to an object (A1) and the coating layer (C2) is at least partially peeled off to provide the structured article (A1M1). Also described herein is a composite (M1C2) in which the surface elements of the material (M1) are covered by a protective coating layer (C2).

An enclosure with a vortex-induced vibration suppression function and a method for suppressing vortex-induced vibration are provided. The enclosure is provided with suction through holes extending through a peripheral wall thereof, the suction through holes are distributed in a circumferential direction of the enclosure. The enclosure is further provided with a suction apparatus, and the suction apparatus can perform suctioning to the suction through holes from outside to inside, to restrain a boundary layer at an outer surface of the enclosure from being detached from the outer surface. By the suctioning, the boundary layer can be “adsorbed” on the outer surface of the tower, thereby restraining or directly preventing the boundary layer from being detached from the outer surface of the tower, and reducing or eliminating the cause of the vertex-induced vibration.

A method for producing an object with riblets on and/or in the surface, around which object a fluid flows during use. A frictional resistance acting on a surface region along a flow direction during a flow around the object in the fluid is calculated and added up to a cumulative frictional resistance over a length of the surface region in the flow direction, after which the riblets are provided on and/or in a partial region of the surface in which an increase in the cumulative frictional resistance is at least 0.9, in particular greater than 1.0 to 0.9. Moreover, a method is provided for modifying a surface of an object around which a fluid flows during use, such as a foil. A structure having riblets is created on and/or in the surface, which structure reduces flow resistance of the object. Furthermore, a fluid flows around an object during use.

A method for producing an object with riblets on and/or in the surface, around which object a fluid flows during use. A frictional resistance acting on a surface region along a flow direction during a flow around the object in the fluid is calculated and added up to a cumulative frictional resistance over a length of the surface region in the flow direction, after which the riblets are provided on and/or in a partial region of the surface in which an increase in the cumulative frictional resistance is at least 0.9, in particular greater than 1.0 to 0.9. Moreover, a method is provided for modifying a surface of an object around which a fluid flows during use, such as a foil. A structure having riblets is created on and/or in the surface, which structure reduces flow resistance of the object. Furthermore, a fluid flows around an object during use.

In one aspect of the present disclosure, a streamlined body for passing through a fluid is provided. The streamlined body includes an outer surface defining a leading edge and a trailing edge. The leading edge is oriented to pass through the fluid before the trailing edge during movement of the body through the fluid. The streamlined body further includes a plurality of fibers coupled to the outer surface. Each fiber of the plurality of fibers projects away from the outer surface.

In one aspect of the present disclosure, a streamlined body for passing through a fluid is provided. The streamlined body includes an outer surface defining a leading edge and a trailing edge. The leading edge is oriented to pass through the fluid before the trailing edge during movement of the body through the fluid. The streamlined body further includes a plurality of fibers coupled to the outer surface. Each fiber of the plurality of fibers projects away from the outer surface.