91results about How to "Reduce induced drag" patented technology

Systems and methods for providing variable geometry winglets to an aircraft are disclosed. In one embodiment, a winglet includes a base portion configured to attach to a wing. The winglet further includes a body portion. In turn, the body portion includes at least one of a deflectable control surface, a shape memory alloy (SMA) bending plate, and a SMA torque tube. The base portion is configured to attach to the wing such that the body portion projects at an upward angle from the wing.

The invention provides an unmanned aerial vehicle with variable sweepbacks and spans of wings, which comprises a vehicle body, the wings and a tail wing, wherein a cross beam is arranged in the middle of the vehicle body; a mechanism for controlling sweepback changes is arranged between the wings and the cross beam; the mechanism for controlling sweepback changes is a four-bar linkage mechanism which comprises a stepping motor, a driving rod and a pushing rod; and the wings include main wings and auxiliary wings. The auxiliary wings can freely move in or out of the main wings by means of relative displacement between the rack and the gear, resulting in the changes of span. Further, the main and the auxiliary wings are provided with friction wheels to achieve the limiting and vibration-reducing effects. The mechanism for controlling sweepback changes has a small size and light weight and can meet the requirements for unmanned aerial vehicles. Besides, the span change is achieved by therelative displacement between the rack and the gear, the running is stable, and no response lag influence exists.

The invention provides an airplane with a combined-wing layout of a flying wing and forward-swept wings. The airplane is characterized in that thin-wing type vertical columns A and B are additionally arranged at the 70% wingspan positions of the outer sides of two side wings of a flying-wing airplane with backward-swept wings, a thin-wing type vertical column C is additionally arranged at the tail part of the flying-wing airplane, and horizontal forward-swept wings are additionally arranged at the top ends of the three thin-wing type vertical columns A, B and C so as to form the combined-wing layout of the flying wing and the forward-swept wings; elevators are arranged on the horizontal forward-swept wings and a rudder is arranged on the vertical column C; a duct type air inlet channel is adopted on the upper wing surface of the flying wing, and cracking type drag rudders are distributed at the thin-wing type vertical columns A and B. The airplane provided by the invention has the advantages that under the condition that the structure strength is effectively guaranteed, the effective aspect ratio of the wings is increased, the induced drag is reduced, the lift-drag characteristics of the airplane are improved, the stealth performance of the airplane is improved, direct-force control of the airplane in the vertical direction is realized and the detecting accuracy under the maneuvering condition is improved.

A wing for an aircraft includes a non-balanced lift gradient because as a result of at least one propeller slipstream flowing onto the wing the induced drag of the wing is increased. To reduce the increased induced drag, the wing comprises a first region with a reduced local wing camber and/or reduced local twist, and a second region with an increased local wing camber and/or increased local twist. The first region is defined as a wing surface situated downstream of the propeller slipstream, upstream of which wing surface the blades of the propeller move upwards. The second region is defined as a wing surface situated downstream of the propeller slipstream, upstream of which wing surface the blades of the propeller move downwards.

The invention discloses an inclined fixed wing unmanned plane. The inclined fixed wing unmanned plane comprises a plane body and a wing inclined mechanism which can incline the wings, wherein the two sides of the plane body are provided with at least one pair of wings, and the tail of the plane body is also provided with a tail wing; and each wing is fixedly provided with a power device, each power device is connected with a screw propeller, the wings and the power devices are fixedly arranged together and can simultaneously move, and the rotation surfaces of the screw propellers are perpendicular to the horizontal planes of the wings all the time. The inclined fixed wing unmanned plane adopting the technical scheme can vertically take off and land and can realize high the cruising speed and power utilization efficiency and reasonable structure of a fixed wing plane; as the preferred technical scheme, the wings are both provided with subsidiary wings which are controlled by the wing inclined mechanism, and the power devices are all fixedly arranged on the middle parts of the wings; and the wings have enough rigidity and intensity, the wings are prevented from deforming because the power devices are fixedly arranged, and the localization of the wings is exact in revolution and fixation.

The invention provides a multi-rotor wing unmanned aerial vehicle, and a system and a flight control method thereof. The unmanned aerial vehicle comprises a machine frame and a horizontal driving device; a main rotor swing and a main rotor swing motor which is connected with the main rotor swing are arranged on the machine frame; the rotating axis direction of the main rotor swing is perpendicular to the horizontal plane of the machine frame; the horizontal driving device is arranged below the machine frame, and the direction of the driving force provided by the horizontal driving device is perpendicular to the rotating axis direction of the main rotor wing, wherein the main rotor wing motor and the horizontal driving device are both connected with a flight control board. No matter the multi-rotor wing unmanned aerial vehicle is in a hovering state or a running state, the attitude angle of the multi-rotor wing unmanned aerial vehicle is kept near zero all the time, and the problem of instantaneous height falling of the unmanned aerial vehicle caused by the inclining of the attitude angle can be avoided; the running power can be provided by the horizontal driving device without relying on the inclining of an attitude; therefore, the attitude of the unmanned aerial vehicle is stilled kept horizontally in the running process.

The present invention discloses a high-aspect-ratio wing frame architecture design method and relates to the technical field of aircrafts. The design method comprises a rigid wing optimization step and an elastic wing optimization step. The rigid wing optimization step comprises generating an initial population of the wing architecture, performing lift-drag ratio calculation to obtain a local optimal solution, then carrying out optimizing calculation, performing lift-drag ratio calculation on the local optimal solution and comparing with the local optimal solution obtained after the initial population is subjected to the lift-drag ratio calculation, and finally judging the globally optimal solution; and the elastic wing optimization step comprises calculating the aerodynamic load borne by an elastic wing during an flight, then calculating the elastic deformation of the wing, solving the true form of the wing structure under elastic balance at the flight state through multiple iterative computations to obtain the flight load after the elastic deformation and acquire the twist angle of a wing profile architecture, and thus completing the design of the wing frame architecture. The wings designed through the high-aspect-ratio wing frame architecture design method have good geometrical aerodynamic twist angle distribution, the lift distribution is better, the smaller induced resistance can be produced, the best lift-drag ratio is obtained, and thus the cruising efficiency is improved.

The invention relates to a composite material air propeller and a preparation die and a preparation method thereof. The composite material air propeller comprises an upper wall plate and a lower wall plate, wherein the upper surface and the lower surface of the upper wall plate are respectively an upper wall plate outer appearance surface and an upper wall plate inner appearance surface; the upper surface and the lower surface of the lower wall plate are respectively a lower wall plate inner appearance surface and a lower wall plate outer appearance surface; the upper wall plate outer appearance surface and the upper wall plate inner appearance surface are fixedly connected with each other through peripheral glue to form a composite material air propeller whole body; and a cavity is formed inside the composite material air propeller whole body. The composite material air propeller is of a split type structure, and the composite material air propeller is hollow; therefore, the composite material air propeller is simple in structure, easy to manufacture, low in cost and light in weight and has the structural characteristic that the tip is bent up, so that the inducing resistance of the composite material air propeller is greatly reduced; and the composite material air propeller is very favorable for application and development of multi-rotor-wing aircrafts.

The invention relates to a wind turbine blade with a split winglet at the apex, which belongs to the field of wind power generation and comprises a winglet (1), a root connecting part (2) and a main blade (3), wherein the winglet (1) is composed of n sub wings, n is 2 or 3, and all the sub wings are trapezoid-shaped with the same taper and sweepback (12), the n sub wings are provided with different anhedrals; the root connecting part (2) extends out of a main blade apex (11) and is an irregular sphere in shape by taking the wing section of the main blade apex as the standard; the irregular sphere wraps the main blade apex (11) and is connected with the sub wings. According to the invention, the spanwise flow of the blade apex can be reduced, the vortice density of the blade apex without the winglet is dispersed, the induced resistance exerted by the blade apex vortex to the blade is weakened, and the purposes of improving the aerodynamic performance of the wind turbine and restraining the effect of the blade vortex in wake flow are realized, so that the aerodynamic performance is brought into play to the greatest degree.

The flapping-wing fling water automobile includes engine, double-blade air screw propeller, right and left hydraulic screw propellers, right and left wings, control system, safety lifesaving equipment, and four-wheel undercarriage, hanging damper and fuselage, with the wings being connected to the fuselage via mechanical and hydraulic mechanism. The present automobile is one traffic facility for land, water and air use simultaneously, and has high efficiency and maneuverability. Its wings may be folded for land running.

The invention discloses a flying wing type aircraft with a variable wing outer wing sweep back angle and a tiltable small wing. The flying wing type aircraft with the variable wing outer wing sweep back angle and the tiltable small wing comprises an inner wing leading edge, outer wing leading edges, small wings, outer wing trailing edges, an inner wing trailing edge and elevons; outer wings are arranged on the two sides of an inner wing; the small wings are arranged at the tips of the outer wings; the outer wings and the small wings all adopt flexible skin structures; first acting mechanisms are arranged between the outer wings and the inner wing; and second acting mechanisms are arranged between the small wings and the outer wings. The flying wing type aircraft with the variable wing outer wing sweep back angle and the tiltable small wing has the advantages that higher lift drag characteristic of the aircraft is guaranteed, the reachable maximum flying speed of the flying wing type aircraft is increased, and meanwhile, the drag in each speed stage is reduced so that the aircraft can preferably develop the efficiency on a fighter plane.

The invention discloses a high-invisibility lifting-body configuration aircraft without a horizontal tail. The high- invisibility lifting-body configuration aircraft comprises a fuselage(1), a left main wing (21) and a right main wing (22) on both sides of the fuselage (1), a nozzle (3) located on the rear part of the fuselage, and air inlet ducts (41,42)located on the side parts of the fuselage (1), wherein a left winglet (51) is arranged at one end, away from the fuselage (1), of the left main wing (21), and a right winglet (52) is arranged at one end, away from the fuselage (1), of the right main wing (21); the appearance of the left winglet (51) is the same as the appearance of the right winglet (52); the camber angle of left winglet (51) is parallel to the camber angle of the lip of the air inlet duct (41) on the left part of the fuselage (1); and the camber angle of the right winglet (52) is parallel to the camber angle of the lip of the air inlet duct (42) on the right part of the fuselage (1). The high-invisibility lifting-body configuration aircraft without the horizontal tail disclosed by the invention is high in aerodynamic performance and good in invisibility effect.

The invention relates to a technology of an electromagnetic driving aerodynamic vehicle provided with tandem wings, and belongs to the technical field of direct drive between vehicle dynamic devices and wing hub of rotors. The technology of the electromagnetic driving aerodynamic vehicle provided with the tandem wings is mainly applied in spacecraft vehicles and aims at improving aerodynamic efficiency of flight vehicles, at the same time solves the practical application problems of the flight vehicles. The technology of the electromagnetic driving aerodynamic vehicle provided with the tandem wings comprises an electromagnetic driving aerodynamic device provided with the tandem wings. The electromagnetic driving aerodynamic device provided with the tandem wings comprises the tandem wings, a magnetic suspension supporting system, an electromagnetic motor driving system, a duct and a machine frame. The electromagnetic driving aerodynamic device provided with the tandem wings is characterized in that a rotating magnetic field driven by electric energy through the electromagnetic motor driving system directly drives the tandem wings, which are supported and confined by the magnetic suspension supporting system, to generate lifting force by moving in the annular duct formed between the inner wall and the outer wall of the duct, so that the flight vehicle gains lifting force or thrust. The electromagnetic driving aerodynamic vehicle provided with the tandem wings has properties of full electric drive, acetabuliform integrated wing body, vertical lift, safe low altitude flight, high-efficient overload, and long hang time.

The invention relates to an upright grid type net plate which comprises an upper flow guide plate, a plurality of wing plates with large span-chord ratios, steel warp reinforcement plates and a lower flow guide plate. The upright grid type net plate is characterized in that the wing plates with the large span-chord ratios are arranged between the upper flow guide plate and the lower flow guide plate, the upper ends and the lower ends of the wing plates with the large span-chord ratios are connected with the upper flow guide plate and the lower flow guide plate along angles of wedges at the front end of the upper flow guide plate and the front end of the lower flow guide plate, are equidistantly rearwards arrayed and are parallel to one another, the steel warp reinforcement plates are arranged between the upper flow guide plate and the lower flow guide plate and are connected and combined with the various wing plates to form a net plate body which is of a structure with a small span-chord ratio, and the upright grid type net plate is integrally in a grid form. The upright grid type net plate has the advantages that merits of low induced drag and high lift-drag ratios of the wing plates with the large span-chord ratios can be sufficiently played, and the upright grid type net plate is applicable to fishing boats with different gross tons and operation on water of different water layers and is high in water power efficiency.

The invention relates to an upright hook-surface grid-type screen which is composed of an upper diversion plate, a plurality of high-aspect-ratio hook-surface wing plates, drag-steel reinforcing plates and a lower diversion plate. The upright hook-surface grid-type screen is characterized in that the high-aspect-ratio hook-surface wing plates are arranged between the upper diversion plate and the lower diversion plate and are parallelly, backwardly and equidistantly arrayed starting from outer arcs of the front end of the upper diversion plate and the lower diversion plate, and the drag-steel reinforcing plates are connected with the high-aspect-ratio hook-surface wing plates to integrally form a grid type. The low-aspect-ratio upright hook-surface grid-type screen is formed by combination of the high-aspect-ratio hook-surface wing plates, thereby being better in stability and recovery performance, higher in hydrodynamic efficiency and suitable for use of different fishing boats different in gross ton and water operation different in drainage layer.

The invention belongs to the field of wind power generation, and discloses a blade tip winglet, a wind turbine blade and a blade synergy calculation method. The blade tip winglet is arranged at the end part of the wind turbine blade and is used for increasing a power coefficient by reducing induced drag of the wind turbine blade. The blade tip winglet comprises a connecting section and a blade tipsection, and further comprises an arc-shaped section used for smoothly connecting the connecting section with the blade tip section in a transition mode, wherein a sweepback wing structure is formedon the windward side of the blade tip section; parameters of the blade tip section are defined, wherein the parameters comprise a mounting angle, height, an inclination angle, a torsion angle and a sweepback angle; the parameters further comprise an initial position L of the leading edge, and the initial position L is a distance value between the windward leading edge of the connecting section andthe most front end of the bottom of the blade tip section; and the initial position L is set between 0 and 0.20<c> to increase the power coefficient of the blade tip winglet and the connected wind turbine blade. According to the blade tip winglet, the wind turbine blade and the blade synergy calculation method, by defining multiple parameter sizes, the induced drag is integrally reduced, so thatthe lift force is improved, and the power coefficient is increased.