Abstract: The invention relates to a device for conveying heated air to a person and comprises an air-permeable inner sheet and an air-impermeable outer sheet which are connected to one another by welds in order to form a panel-like shape in the inflated state. The welds produce a main duct having, viewed at the inlet end and in the non-inflated state, a main duct width. The main duct is delimited by at least one first series of elongate first welded strips, the first intermediate spaces which are in line with one another. The length of each of these first intermediate spaces, viewed in the non-inflated state, is in each case smaller than the main duct width. The length of each first welded strip is at least 15% of the main duct width and at most 80% of the main duct width.

Abstract: The invention relates to a wind turbine comprising a rotor with a hub and turbine blades, and further comprising a boundary layer control system for the turbine blades. A plurality of pressure chambers is located in the blade distributed over the length of the blade. Each pressure chamber is in communication with the outside of the blade through one or more corresponding openings in the outer surface of the turbine blade. Furthermore a suction channel and a blow channel extend inside the blade for supplying an underpressure and an overpressure respectively to the pressure chamber, each pressure chamber being connected to at least one of said channels through an air passage in which an actively operable valve is located. The valve is connected to a control unit for selectively bringing the pressure chamber into communication with or close it off from said channel(s) so as to blow air out of the pressure chamber or suck air into the pressure chamber through the corresponding opening(s) in the blade surface.

Abstract: The present invention provides an apparatus to increase stability of sports cars equipped with an underbody plate by means of active boundary layer suction applied to the car's underbody panelling (6). The apparatus of the invention comprises one suction device (4) to which ducts are connected coming from a structure of pressure chambers (9) attached to the underbody panelling of the car. The underbody panelling of the car comprises a special porous plastic material (8) to suck air from the boundary layer flowing under the car bottom plate.