Friction resistance reducing layer for object e.g. vehicle, building, has repetitive waveform-like approach flow surface which has overhanging wave tops and cavities and grooves for transporting fluid from fluid boundary layer into cavities

摘要

A friction resistance reducing layer has a repetitive waveform-like approach flow surface (1) with overhanging wave tops (2) and cavities (4) located downstream. The approach flow surface also has grooves (6) located close to the wave tops. The grooves accelerate and guide the fluid e.g. air, in the desired direction, forming parallel oriented air flows (10a,10b). The air flows are rotated to form tornadoes, setting into motion the air present under air flows in the cavities. An independent claim is also included for a method for manufacturing a layer for the purpose of reducing the friction resistance of a fluid relative to an object.