A layout for asymmetric trip strips including a flow passage having a lower wall and an upper wall opposite the lower wall, each of the lower wall and the upper wall including an inner surface, the flow passage having a passage inlet and a length L and a diameter d; multiple skewed trip strips extending from at least one inner surface of the lower wall or the upper wall; and at least one periodic reflection of the skewed trip strips along the flow passage downstream of the passage inlet at a frequency with a length-to-diameter ratio of L/d20.

A structural element for attachment to an outer skin of a vehicle, in particular a transport vehicle, a passenger car, a rail vehicle, an aircraft and/or a watercraft, includes a main fin and a first and a second secondary fin. These secondary fins are arranged next to the main fin such that a first channel is formed between the first secondary fin and the main fin and a second channel is formed between the second secondary fin and the main fin. The first channel and the second channel each have a change in cross-section such that when a fluid flows through the first channel or the second channel, a change in the flow velocity of the fluid occurs. In this way, the flow behavior of a fluid around the vehicle can be influenced and the flow resistance acting on the vehicle can be effectively reduced.

A magnetic insertion meter is disclosed herein. Disclosed insertion meters include in some examples, a sensor head tube having a textured front surface and at least two electrodes. Disclosed insertion meters include a textured front surface adapted to move the separation point of a fluid flowing over the sensor head tube towards the upstream surface as compared to the same sensor head tube without the textured front surface. Methods of measuring flow are also disclosed herein using example magnetic insertion meters.

A method of forming a microstructured surface includes the operations of depositing electrodes on a surface of a substrate and securing a mold against the surface of the substrate containing the electrodes with a tight contact with the electrodes, the mold containing a plurality of cavities therein. Pressure is applied between the mold and the substrate to force material from the substrate into the plurality of cavities around the electrodes to form a plurality of microfeatures. The mold is separated from the substrate.

A hydrofoil cavitating flow control structure includes a hydrofoil. A primary protuberant stripe is disposed in a middle position of a suction side of the hydrofoil, a plurality of symmetrically-distributed secondary protuberant stripes are disposed obliquely at both sides of the primary protuberant stripe, and the plurality of secondary protuberant stripes are uniformly and equidistantly distributed along the length direction of the primary protuberant stripe. By changing geometric parameters such as an included angle between the primary protuberant stripe and the second protuberant stripe, a ratio of cross section diameters and a distribution spacing of the second protuberant stripes along a chord length direction of the hydrofoil and the like, the shedding of cloud cavitation on a hydrofoil surface is effectively suppressed, and cavitation erosion and pressure pulsation generated by cavitation collapse is reduced, thus improving the operation efficiency and the service life of hydraulic machinery.