37results about How to "Increase the maximum lift coefficient" patented technology

The invention provides a high-efficiency pneumatic layout structure of synergistic jet for a high-altitude propeller and a control method. The high-efficiency pneumatic layout structure is characterized in that a plurality of synergistic jet devices are distributed along propeller blades of the propeller in a spanwise sectional manner; each synergistic jet device comprises an air blowing opening formed in a negative-pressure area of the front edge of the upper surface of the propeller, an air suctioning opening formed in a high-pressure area of the rear edge of the upper surface of the propeller, an airflow pipeline arranged in the paddle and an air pump arranged in the airflow pipeline; the air blowing opening and the air suctioning opening are communicated by the airflow pipeline to form an air-blowing and air-suctioning loop; the air pump is used for driving air suctioning and air spraying to be implemented simultaneously, and by control of the air pump, the air suctioning amount and the air spraying amount are same. The high-efficiency pneumatic layout structure provided by the invention has the advantages that the defects of the traditional propeller layout and the common flow control technology can be made up, and the working efficiency of a propelling system of the high-altitude propeller can be improved.

The invention discloses a method for designing a special wind turbine airfoil profile and a special wind turbine wing profile obtained by the designing method. In the invention, a corresponding airfoil profile can be obtained by expressing the geometrical shape of an airfoil profile with a simple high-order polynomial shape function and altering the coefficient of the shape function polynomial according to a special constraint condition. The special wind turbine airfoil profile is in a Reynolds number range with Re=1*106-3*106, has low-airfoil profile surface roughness sensitivity, higher lift coefficient and maximum lift drag ratio, as well as high lift drag ratio and favorable structural property in a larger attack angle range, and has favorable compatibility and acoustical property compared with other wind turbine airfoil profiles.

The invention discloses a dynamic base station for AUV recovery, belongs to the technical field of underwater robot recovery, and aims to solve the problems of instability in docking recovery, difficulty in operation, large drag resistance and certain potential safety hazards existing in the prior art. The dynamic base station comprises a recovery base station body, two attitude regulators symmetrically arranged on the recovery base station body, a connecting ring fixed on the recovery base station body, a guide cover, a locking device, a position detector, and a main controller, wherein one end of the guide cover is coaxially and fixedly connected with one end of the connecting ring, and the other end of the guide cover is a free end with opening adjustable; one end of the locking deviceis fixedly connected with the other end of the connecting ring, and an underwater robot which enters the dynamic base station is clamped or loosened through the locking device; the position detector is fixedly connected with the other end of the locking device; and the main controller is arranged in the recovery base station body, the rotating speed of the two attitude regulators is controlled through the main controller, and the main controller receives the detection signals of the position detector to control the locking device to clamp or release the underwater robot.

The invention provides a high lift and low torque characteristic 12%-thickness rotor-wing airfoil suitable for all working conditions, The 12%-thickness rotor-wing airfoil is characterized in that the radius of a front edge is reduced, so that shock-wave strength is reduced, the resistance is further reduced, and a lift-drag ratio is increased; the thickness of the lower part of the airfoil is increased to some extent, so that the torque is reduced. Compared with a high lift drag ratio and high resistance divergence Mach number 12%-relative-thickness rotor-wing airfoil OA312 disclosed abroad at present, the rotor-wing airfoil provided by the invention completely meets design indexes under multiple working conditions, and has a high lift drag ratio, a high resistance divergence Mach number, a high maximum lift coefficient and a smaller torque coefficient; when Ma is equal to 0.77, the zero lift drag is lower, so that the performance requirements of a high performance helicopter rotor blade design can be met.

The invention relates to a three-section type fixed wing unmanned aerial vehicle provided with a sprinkling system. Each wing of the unmanned aerial vehicle is of a three-section type wing-type structure and comprises a slat arranged at the front edge of the wing, a main wing arranged in the middle of the wing and a wing flap arranged at the rear edge of the wing. Each main wing comprises a central wing body and outer wing bodies arranged on the two sides of the central wing body, and each wing flap comprises a wing flap body arranged at the rear edge of the corresponding central wing body and flaperons arranged at the rear edges of the corresponding outer wing bodies; and the sprinkling system comprises a container, a pump, a spray pipe and a spray head, the spray head is connected with the pump through the spray pipe, and the pump is connected with the container through the spray pipe. The three-section type fixed wing unmanned aerial vehicle provided with the sprinkling system has the higher maximum lift coefficient so as to have higher maximum lift; and meanwhile, the weight-carrying, flying and sprinkling performance of the fixed wing unmanned aerial vehicle is improved, and thus the fixed wing unmanned aerial vehicle has the higher sprinkling efficiency.

The invention belongs to the technical field of aircrafts, and particularly relates to a wing with pits. The wing comprises a front edge, an upper surface, a lower surface, a rear edge and a wing body. The front edge is thick and round, the upper surface is an upwards-protruding curved surface, the lower surface of a plane or a curved surface which slightly protrudes downwards or a curved surface which is slightly concaved upwards, the identical small pits are evenly distributed in all the area, from the thickest portion of the wing to the rear edge, of the upper surface in the wing chord direction, the average depth of the small pits is about 0.25 mm, the largest boundary dimension of the small pits is between 1 mm and 10 mm, and the clear distance between every two adjacent small pits is between 1 mm and 3 mm. The largest lift-drag ratio of the wing is large, the range of the effective angle of incidence is large, and the wing is not prone to stalling, high in efficiency and high in strength.

The invention discloses a special-shaped wing profile, belongs to the technical field of air vehicles and particularly relates to a wing. The special-shaped wing profile comprises a leading edge, an upper surface, a lower surface, a trailing edge, a wing root, a wing tip and a wing body, wherein the leading edge is a combination of an oblique S-shaped curve and a straight line, the trailing edge is straight, and the wing tip is sharp. A wing is divided into three portions by a plane parallel to the wing root end face along the wingspan direction: the first portion refers to a portion close to the wing root and is roughly a profile with a convex upper and a flat lower and with medial relative thickness, the radius of the leading edge is medial, and a position with maximum thickness is in the back; a second portion refers to a middle portion and is a thick profile with a convex upper and a concave lower, the radius of the leading edge is large, and a position with maximum thickness is in the front; a third portion is a portion close to the wing tip and is roughly a thin profile with double convex surfaces, the radius of the leading edge is small, and a position with maximum thickness is in the middle; the three portions are in smooth connection. The wing with the special-shaped wing profile is large in effective incidence, less prone to stalling and high in efficiency.

The invention relates to a three-section type fixed-wing unmanned aerial vehicle provided with a protection device. A wing of the fixed-wing unmanned aerial vehicle is of a three-section type wing-shaped structure and comprises a slat which is arranged at the front edge of the wing, a main wing which is arranged in the middle of the wing and a wing flap which is arranged at the rear edge of the wing; the main wing comprises a central wing and outer wings located at two sides of the central wing; the wing flap comprises a wing flap arranged at the rear edge of the central wing and secondary wing flaps arranged at the outer edges of the outer wings; a forward pull type screw propeller is arranged at the front end of a fuselage; a protection device comprises a screw propeller protection device, a wingtip protection device and an empennage protection device. The three-section type fixed-wing unmanned aerial vehicle provided by the invention has the advantages that the three-section type fixed-wing unmanned aerial vehicle has a higher lift coefficient and the aerial vehicle has higher maximum lift; meanwhile, the fuselage and the screw propeller can be reasonably protected.

The invention discloses a canard flying wing aerodynamic layout unmanned aerial vehicle, and the unmanned aerial vehicle comprises main wings, full-motion canard wings, a full-motion vertical tail wing and a vehicle body, and the flying performance of a fixed wing aircraft is well improved by fusing flying wing aerodynamic layout and canard aerodynamic layout. The main wings adopt flying wing structures, so that the structural mass can be reduced, the effective lift area is increased, and the immersion area is reduced. The full-motion canard is added in front of the main wing, so that the pitching control range of the unmanned aerial vehicle is widened, and meanwhile, the maximum lift coefficient of the flying wing is increased. Compared with the performances of a conventional aerodynamiclayout fixed-wing unmanned aerial vehicle, the lifting force is improved by about 13.3%, the effective load is improved by about 8.6%, the unmanned aerial vehicle has outstanding performance in the aspect of low speed, the minimum flight speed can be reduced to 6 m/s, and the flight speed is reduced by about 37% compared with a single-flying-wing type aerodynamic layout unmanned aerial vehicle. Compared with a single-flying-wing type aerodynamic layout unmanned aerial vehicle, a pair of canard wings is additionally arranged on the structure, so that the lift-drag ratio of the unmanned aerial vehicle is reduced by about 5.25%.

The invention relates to a three-stage fixed-wing unmanned aerial vehicle. A wing of the unmanned aerial vehicle is of a three-stage wing shaped structure, the wing comprises a slat arranged at the front edge of the wing, a main wing arranged in the middle of the wing and a flap arranged at the rear edge of the wing, the main wing comprises a central wing and outer wings arranged on both sides of the central wing, the flap comprises a flap body arranged at the rear edge of the central wing and auxiliary flaps arranged at the rear edges of the outer wings. An advantage of the three-stage fixed-wing unmanned aerial vehicle is that use of the three-stage wing airfoil is an innovate point. Compared with an existing single-stage or two-stage airfoil used in the unmanned aerial vehicle, the three-stage airfoil has a higher maximum lift coefficient, so that the unmanned aerial vehicle has a higher maximum lift. The increase in maximum lift allows the unmanned aerial vehicle to have a higher load and a lower stalling speed, take off and land on shorter runways, and have better low-speed flight performance.