The invention discloses an aircraft generating a larger lift from its interior. The fluid channel inside the aircraft communicates with the engine and the ports on the upper surface of the outer shell. With the powerful suction of the engine, the fluid on the upper surface of the outer shell is quickly sucked into the fluid channel via respective ports under conditions of long path, large area, high speed and low air pressure, which results in large lift from the interior of the aircraft. In the course of generating the lift, the fluid resistances of the fluid wall and the fluid hole are sucked into the fluid channel through the ports at the front and the surrounding area of the aircraft, then high-speed fluid is emitted from the rear port. This approach contributes greatly to the transformation of the existing aircraft. The unified big wing significantly improves the lift, the speed and the carrying capacity of the existing aircraft with lowered energy consumption.

A system and method for controlling hypersonic boundary layer transition for a hypersonic flight vehicle are disclosed. The reduction or elimination of hot streaks that naturally occurs in the boundary layer transition process during hypersonic flight is achieved by utilizing various techniques. One such technique utilizes roughness elements to counteract streak development. The techniques for reducing or eliminating the streaks are tailored such that the nonlinear stages of transition are profoundly altered. This results in significant drag reduction, and consequently an increase in range of the vehicle, and also a reduction of the weight penalty due to the Thermal Protection Systems (TPS) as less protective material would be required, thus allowing for an increased payload and/or range of the vehicle.

A system and method for controlling hypersonic boundary layer transition for a hypersonic flight vehicle are disclosed. The reduction or elimination of hot streaks that naturally occurs in the boundary layer transition process during hypersonic flight is achieved by utilizing various techniques. One such technique utilizes roughness elements to counteract streak development. The techniques for reducing or eliminating the streaks are tailored such that the nonlinear stages of transition are profoundly altered. This results in significant drag reduction, and consequently an increase in range of the vehicle, and also a reduction of the weight penalty due to the Thermal Protection Systems (TPS) as less protective material would be required, thus allowing for an increased payload and/or range of the vehicle.

Provided is the film that can reduce aerodynamic drag and enhance aerodynamic performance. The film according to an embodiment is a film (1) to be attached to a moving body that moves in a predetermined moving direction, extends along a second direction (D2) being the moving direction, and includes recesses and protrusions (2A) configured to enhance aerodynamic performance of the moving body on a surface of the film.

Provided is the film that can reduce aerodynamic drag and enhance aerodynamic performance. The film according to an embodiment is a film (1) to be attached to a moving body that moves in a predetermined moving direction, extends along a second direction (D2) being the moving direction, and includes recesses and protrusions (2A) configured to enhance aerodynamic performance of the moving body on a surface of the film.

An apparatus configured to reduce acoustic interactions between a propeller and a surface of an aircraft positioned downstream of the propeller includes a surface modification element of the surface of the aircraft. The surface modification element defines a modified contour of the surface. The modified contour is configured to decorrelate a phase distribution of a plurality of sound sources within a source field positioned on at least a portion of the surface.

An apparatus configured to reduce acoustic interactions between a propeller and a surface of an aircraft positioned downstream of the propeller includes a surface modification element of the surface of the aircraft. The surface modification element defines a modified contour of the surface. The modified contour is configured to decorrelate a phase distribution of a plurality of sound sources within a source field positioned on at least a portion of the surface.

A profiled element used is disclosed for generating a force, the profiled element comprising a material having an active surface; a plurality of cavities located on the active surface of the material, the plurality of cavities comprising pin holes, each pin hole having an opening of a micrometric size on the active surface and a depth of a micrometric size greater than its diameter; wherein each pin hole is hermetically sealed on the opposite side of the cavity; and further wherein an airflow circulation against the active surface of the material causes a pressure change on the active surface and inside each of the plurality of cavities thereby generating a force.

A cross-flow fan includes a plurality of fan blades provided to be circumferentially spaced apart from each other. The fan blade has an inner edge portion arranged on the radially inner side to/from which air flows in/out, and an outer edge portion arranged on the radially outer side to/from which air flows in/out. Fan blade has a blade surface extending between the inner edge portion and the outer edge portion. The blade surface includes a pressure surface arranged on the rotation direction side of the cross-flow fan and a suction surface arranged on the back side of the pressure surface. When cut along a plane orthogonal to the rotation axis of the cross-flow fan, the fan blade has a blade cross-sectional shape in which a concave portion concave from the pressure surface is formed.

A cross-flow fan includes a plurality of fan blades provided to be circumferentially spaced apart from each other. The fan blade has an inner edge portion arranged on the radially inner side to/from which air flows in/out, and an outer edge portion arranged on the radially outer side to/from which air flows in/out. Fan blade has a blade surface extending between the inner edge portion and the outer edge portion. The blade surface includes a pressure surface arranged on the rotation direction side of the cross-flow fan and a suction surface arranged on the back side of the pressure surface. When cut along a plane orthogonal to the rotation axis of the cross-flow fan, the fan blade has a blade cross-sectional shape in which a concave portion concave from the pressure surface is formed.