165results about How to "Improve aerodynamic performance" patented technology

The invention discloses a rotor aerodynamic force and flow field simulation method, and relates to the field of aerospace, and the method comprises the steps: generating a blade skin grid according to rotor configuration parameters, and constructing a Cartesian background grid; constructing a calculation model of variable-diameter rotor flow field simulation based on the blade skin grid and the Cartesian background grid; and in the constructed calculation model for variable-diameter rotor flow field simulation, a high-precision CFD method suitable for variable-diameter rotor flow field solving is established, rotor aerodynamic force and a flow field in the dynamic diameter changing process are simulated, and a CFD calculation result is output. The aerodynamic performance of the rotor wing can be improved by simulating the variable-diameter rotor wing flow field.

The invention discloses a distributed electric propulsion box type wing ground effect aircraft which comprises a main fuselage, the two sides of the main fuselage are connected with one ends of sweepback wing main wings, one ends of two empennages above the tail of the main fuselage are connected with the main fuselage through vertical tails, and the other ends of the two empennages are connected with the other ends of the two main wings through end plates respectively. The empennage is connected with a plurality of high ducted fans directly driven by a motor, an elevator and an aileron are arranged at the rear part of the empennage, a rudder is arranged at the rear part of the vertical fin, and the elevator, the aileron and the rudder are controlled by a flight control system and are mutually independent. The ground-effect aircraft provided by the invention adopts a box-type wing structure formed by combining the sweepback main wing and the sweepforward empennage, has better aerodynamic performance in a take-off and climbing low-speed flight state, and can provide larger lift force and better maneuvering characteristics.

The invention discloses a multi-degree-of-freedom morphing wing based on a zero poisson ratio superstructure, and belongs to the technical field of morphing wings. The wing comprises a front edge section, a wing body and a rear edge section which are sequentially connected, the front edge section comprises an inner side front edge plate, a middle front edge plate and an outer side front edge plate, the wing body comprises a plurality of zero-Poisson-ratio honeycomb structures, each zero-Poisson-ratio honeycomb structure is formed by arraying a plurality of zero-Poisson-ratio unit cell cubic structures, and the adjacent zero-Poisson-ratio unit cell cubic structures share a connecting rod; the rear edge section comprises an inner side rear edge plate, a middle rear edge plate and an outer side rear edge plate; the inner-side front edge plate and the inner-side rear edge plate, the middle front edge plate and the middle rear edge plate, and the outer-side front edge plate and the outer-side rear edge plate are respectively connected through zero-Poisson-ratio honeycomb structures which are arranged along the chord length direction of the wing; the two sides of the middle front edge plate are connected with the inner side front edge plate and the outer side front edge plate through zero-Poisson-ratio honeycomb structures arranged in the extension direction of the wing correspondingly, and the two sides of the middle rear edge plate are connected with the inner side rear edge plate and the outer side rear edge plate through zero-Poisson-ratio honeycomb structures arranged in the extension direction of the wing correspondingly. The wing has four deformation functions of variable elongation, chord length, dihedral angle and camber, so that the aircraft can adapt to different flight environments and tasks.

The invention discloses a four-flapping-wing aircraft and an attitude control system thereof, and relates to the technical field of micro aircrafts, and the four-flapping-wing aircraft comprises a fixed rack, a guide rod, a slide block mechanism, a pitching frame, a rolling frame, a pulley and a chord driving system. The fixed rack is provided with four cantilevers, a sliding block mechanism is installed on a guide rod, and the pitching frame and the rolling frame control pitching and rolling actions through steering engines respectively. The four pulleys are connected to the pitching frame, and each pulley is hinged to one wing. The string driving system comprises a guide wheel, a string and a crank, one end of the string is connected with the slider mechanism, and the other end bypasses the guide wheel and is connected with the pulley to realize wing flapping. Through the deflectable spars and fine steering engine control, efficient aerodynamic performance, enhanced thrust output and excellent flight flexibility and adaptability are achieved, meanwhile, due to the design of the crank sliding blocks, structural stress is relieved, the service life is prolonged, the aircraft adapts to multiple flight modes, and the environment adaptability and task execution efficiency of the aircraft are improved.

The invention discloses a ducted fan design method and device based on a similarity criterion, and the method comprises the steps: taking a small ducted fan as a prototype, obtaining basic aerodynamic performance information of the small ducted fan through aerodynamic performance simulation, and obtaining a similarity relation of the aerodynamic performance of the ducted fan through a dimension analysis method in combination with a similarity theory; basic information such as the geometric dimension, the rotating speed and the incoming flow speed of the target large ducted fan is rapidly predicted; then, numerical simulation is conducted on the predicted large ducted fan, the aerodynamic performance of the large ducted fan is further verified, and therefore rapid design and performance prediction of the large ducted fan are achieved. According to the method, the large ducted fan is designed by utilizing the existing mature small ducted fan based on the similarity criterion, so that the scientificity and accuracy of the design are improved, the test and calculation cost is remarkably reduced, and the research and development period is shortened. And meanwhile, the aerodynamic performance and efficiency of the ducted fan can be improved.

The invention belongs to the technical field of dynamic temperature testing, and particularly relates to a dynamic total temperature probe based on double film platinum resistors, which comprises a probe head, a probe support rod, two film platinum resistors and two lead holes. The head of the probe is in a semi-spherical shape and directly faces a main stream to form a vertical section, the two thin-film platinum resistors are arranged on the section along the axis of the probe, leads of the thin-film platinum resistors are led out through lead holes located behind the thin-film platinum resistors, a four-wire system connection mode is adopted, and a cylindrical surface of a supporting rod of the probe and the vertical section are in a Vitdosski curve shape. The calibration and measurement data processing method provided by the invention greatly improves the measurement frequency response and the measurement precision of the probe, is suitable for measuring the transient temperature fields of the inlet, the outlet and the interstage of the turbomachinery, can quickly and accurately measure the transient temperature change of the turbomachinery under different working conditions, and provides a technical means for the transient temperature measurement of the turbomachinery.

The invention discloses a flight-oriented fan wing trailing edge adjusting device, and relates to the technical field of aircrafts, the flight-oriented fan wing trailing edge adjusting device comprises a trailing edge angle adjusting mechanism, a rectification angle adjusting mechanism, a circular end plate and a rectification plate, the trailing edge angle adjusting mechanism comprises a steering engine, a first connecting rod mechanism, a trailing edge plate and a rotating shaft; the steering engine is fixedly installed on the circular end plate and controls the rear edge plate to move through the first connecting rod mechanism, the rotating shaft is arranged on one side of the rear edge plate, and the rear edge plate is hinged to the rectifying plate through the rotating shaft. By freely adjusting the trailing edge angle and the rectification angle, the aerodynamic force of the fan-wing aircraft is changed, the lift force and thrust distribution is improved, the aerodynamic effect is enhanced, the energy consumption is reduced, and the flight efficiency is improved. The fan wing trailing edge adjusting device is applied to a serial fan wing, forward coupling gain between two wings is achieved by changing the size of a trailing edge angle and a rectification angle, different flight conditions are met, various flight requirements are flexibly met, and the load performance and the endurance are optimized.

The invention discloses a wide-adaptability variable-geometry turbine of a variable-cycle aero-engine and a flow adjusting structure of the wide-adaptability variable-geometry turbine of the variable-cycle aero-engine, a turbine guider in the structure is integrally arranged at the upstream position of a turbine rotor and is provided with a plurality of guider blades, each blade is provided with a front cavity and a rear cavity, the cavities are connected with the last stage of an air compressor through an air entraining connector, and the air entraining connector is connected with the tail stage of the air compressor. And high-pressure airflow is guided in. The suction face front airflow nozzle and the pressure face tail airflow nozzle are used for jetting airflow to the main flow channel, the pneumatic blocking effect with the local flow speed reduced is formed, and the throat area and the airflow angle characteristic of the guider are adjusted. The airflow adjusting device comprises a flow adjusting valve and a pressure adjusting valve, the flow and pressure of airflow are controlled, the airflow injection characteristic is accurately adjusted, and the turbine flow and efficiency are optimized. The turbine flow adjusting precision can be effectively improved, the mechanical complexity is reduced, the turbine efficiency is improved, the service life of an engine is prolonged, the requirements under different flight working conditions are met, and the important application value is achieved.

The invention provides a precision forging method for an adjustable blade of an aero-engine based on titanium alloy, which can realize precision forging forming of the blade of the titanium alloy aero-engine, enables the blade profile size of a blade forging to directly reach the size of a finished product, does not need to be machined again, is high in product percent of pass and good in air passage consistency, also can keep the continuity of a metal flow line, and is suitable for large-scale production. The mechanical property and the aerodynamic performance are high, and the surface integrity and the metallographic structure meet the design requirements. The method comprises the following steps of blanking, surface cleaning, glass lubricant spraying, heating blank making, surface cleaning, glass lubricant spraying and forging, and is characterized in that the forging procedure comprises heating upsetting, heating pre-forging and heating finish forging, and the surface cleaning and glass lubricant spraying are respectively carried out after each procedure of heating upsetting, heating pre-forging and heating finish forging.

The invention provides a design method of an asymmetric guide vane diffuser for a centrifugal compressor, and belongs to the technical field of distributed new energy and aviation power. The method comprises the steps that the basic size and shape of the diffuser are determined based on the outlet airflow condition of the centrifugal compressor; according to the connecting mode of the diffuser and the volute, the design requirement of the asymmetric guide vane is determined; according to the number of the blades, the numbers and initial positions of the blades are determined, and according to airflow conditions and blade outlet boundary requirements, the angles and the positions of the blades are adjusted; based on the preliminary design, geometric parameters of the blade are calculated, and the geometric parameters comprise the trailing edge distance, the included angle and the mean camber line coordinate; and gradually optimizing the geometric parameters through an iterative calculation method. Through iterative optimization and CFD simulation, the aerodynamic performance of the diffuser can be remarkably improved, the flow loss is reduced, and the overall efficiency of a gas compressor is improved.

The invention discloses an axial flow fan, an injection system and a range hood, and relates to the technical field of kitchen electric appliances. The axial flow fan comprises a rectification air duct and a movable blade assembly, and a noise reduction groove penetrating in the circumferential direction is formed in the inner wall of the rectification air duct; the movable blade assembly comprises a movable impeller, the movable impeller is rotationally arranged in the rectification air duct, the movable impeller comprises a plurality of movable blades arranged at intervals in the circumferential direction, and the blade tops of the movable blades are located in the noise reduction grooves. The axial flow fan can reduce noise and improve aerodynamic performance so as to improve user experience.

The invention relates to the field of aircrafts, in particular to a portable single-person low-altitude vector jet aircraft with a folding wing structure, the portable single-person low-altitude vector jet aircraft comprises a rack part, a power part and a load part, the power part is arranged below the rack part, and the load part is arranged below the power part; according to the portable single-person low-altitude vector jet aircraft with the folding wing structure, through the design of the telescopic framework of a multi-connecting-rod structure, the aircraft can be easily folded when not used, the occupied space is small, carrying and storage are convenient, and the problems that a traditional single-person aircraft is large in size and difficult to carry are solved; the applicability and convenience of the aircraft are improved; meanwhile, the structural strength of the wings in the unfolded state is ensured through the multi-point supporting design of the telescopic framework, the stability and safety of the aircraft are improved, the air resistance of the aircraft is reduced through the design of the wing skin, the protective cover, the conical cover, the wind tunnel and the fairing, the aerodynamic performance is effectively improved, and the aircraft is more efficient in the flight process.

The invention relates to the technical field of silencing sheets, in particular to a comprehensive type super-structure sound absorption silencing sheet which comprises a suction skin and an outer cover and further comprises a low-frequency sound absorption structure arranged in the suction skin, and the low-frequency sound absorption structure comprises a first micro-perforated plate, a second micro-perforated plate, a third micro-perforated plate, a first support and a partition plate. The number of the first supports is multiple, the two sides of each first support are fixed to the inner wall of the suction skin, the partition plates are fixed between the adjacent first supports, the third micro-perforated plate and the second micro-perforated plate are fixed to the inner sides of the front partition plate and the rear partition plate respectively, and the first micro-perforated plate is fixed to the inner side of the suction skin. A first sound absorption module is filled between the micro-perforated plate II and the micro-perforated plate III; the sound absorption material has good sound absorption performance for low frequency, intermediate frequency and high frequency, and can be applied to a complex sound environment, so that good full-frequency noise reduction can be achieved.

The invention discloses a turbine device for improving the sealing performance of a rim and the aerodynamic performance of a turbine, which comprises a static-turntable cavity and a rotor hub end wall, and the rotor hub end wall is arranged above the static-turntable cavity; the static-rotating disc cavity comprises a static disc wall face, a jet flow groove is formed in the position, close to the wheel flange, of the static disc wall face, and the end wall of the rotor hub is a non-axisymmetric end wall. The vortex structure in the rim gap is broken through the jet flow groove, so that the rim sealing performance of the static-rotating disc cavity is improved, the vortex strength of an inlet of the downstream rotor is reduced, and a good air inlet condition is provided for the non-axisymmetric end wall of the downstream rotor to control secondary flow; the end wall of the rotor hub is arranged to be a non-axisymmetric end wall, so that the development of secondary flow of the hub in the flow direction is delayed, and the aerodynamic performance of the turbine is integrally enhanced. By means of the combined structure, the turbine aerodynamic performance can be improved while the sealing performance of the static-rotating disc cavity rim is improved.

The invention relates to a high-temperature alloy solid blade wax mold reversible deformation tool design method, belongs to the technical field of precision casting, and solves the problems that the correction precision is limited during reversible deformation of an existing blade wax mold; and a specific, simple and standardized blade wax mold reversible deformation method does not exist. The invention provides a specific, simple and standardized blade wax mold reversible deformation method, which comprises the following steps: firstly, analyzing according to a cross section to obtain a blade body size deformation rule, then designing a blade wax mold reversible deformation tool according to the deformation rule, and finally, carrying out reversible deformation on the blade wax mold by virtue of the tool. According to the method, the deformation difference between the air inlet and exhaust edges of the blade wax mold and the middle of the blade body is considered, cracks on the air inlet and exhaust edges of the blade wax mold are avoided, the correction precision is improved, and the purpose of effective deformation is achieved.

The invention discloses a fan and an air duct type air conditioner. The fan comprises a volute. The volute comprises a volute body and a movable inner shell. The volute body is provided with a side air outlet located in the side face and a lower air outlet located in the bottom face. The movable inner shell is arranged on the inner side of the volute body and provided with a ventilation opening. The movable inner shell is rotatably arranged around the axis of the fan relative to the volute body so that the fan can be switched between the side air outlet state and the lower air outlet state. In the side air outlet state, the ventilation opening communicates with the side air outlet to form a side air outlet channel used for supplying cold air. In the lower air outlet state, the ventilation opening communicates with the lower air outlet to form a lower air outlet channel used for supplying hot air. On the plane perpendicular to the axis of the draught fan, the projection of the side air outlet channel forms a side air outlet volute molded line. And the projection of the lower air outlet duct forms a lower air outlet volute molded line. The shape of the side air outlet volute molded line is different from that of the lower air outlet volute molded line. The working noise of the fan is effectively reduced.

The invention discloses a joint control wing design method for broadband shock wave buffeting, and belongs to the field of flow cooperative control, and the joint control wing design method comprises the steps: designing a sweepback wing geometric model, simulating to obtain a flow field snapshot and a response curve of a sweepback wing, processing by using DMD dynamic modal decomposition to obtain a first-order dominant modal structure cloud picture, and calculating the flow field snapshot and the response curve of the sweepback wing according to the first-order dominant modal structure cloud picture. Determining a buffeting type, a control device and a position parameter design method of the sweepback wing to obtain an updated sweepback wing geometric model; and verifying according to the updated buffeting type and the updated response curve to complete the design of the sweepback wing. Based on the DMD dynamic mode decomposition technology, the buffeting type is obtained by analyzing the flow field data of the sweepback wing, the corresponding control device and the position parameter design method are selected according to the flow characteristics of the wing, wing buffeting can be restrained and eliminated in a targeted mode, the parameter optimization difficulty in wing design is reduced, and the design efficiency is improved.

The invention provides a posaconazole dry powder inhalant and a preparation method thereof, and relates to the technical field of medicine preparation. The posaconazole dry powder inhalant provided by the invention comprises posaconazole, a space stabilizer and a surfactant, has excellent aerodynamic performance, good redispersibility, higher solubility and dissolution rate and excellent antifungal activity, and in-vivo pharmacokinetic evaluation shows that the lung concentration is higher and the whole-body exposure is lower. The posaconazole dry powder inhalant is prepared by adopting a wet medium grinding and spray drying technology, and a nanocrystal technology is combined with pulmonary administration, so that the obtained posaconazole dry powder inhalant has excellent aerodynamic performance, good redispersibility, higher solubility and dissolution rate, and can be used for preparing a medicine for preventing and treating diseases. And a strategy with a wide prospect is provided for targeted delivery of a drug with poor solubility to an infected part deep in the lung.

The invention provides an indoor unit of an embedded air conditioner and the embedded air conditioner. The indoor unit comprises an indoor fan, an air inlet is formed in the lower side of the indoor fan, and an air outlet is formed in the periphery of the indoor fan; the indoor heat exchanger extends in the peripheral direction of the indoor fan and is arranged opposite to the air outlet, and the indoor heat exchanger is arranged around the indoor fan; the side wall face, facing the air outlet, of the indoor heat exchanger forms a heat exchange face, and an air guide mounting plate is arranged on the heat exchange face, extends in the width direction of the indoor heat exchanger and is parallel to the central axis of the indoor fan. And at least the part, connected to the heat exchange surface, of the air guide mounting plate is perpendicular to the heat exchange surface. According to the indoor unit and the embedded air conditioner provided by the invention, the aerodynamic performance between the fan blade air outlet and the indoor heat exchanger can be effectively improved, the generation of vortexes is reduced, and the generation of fin noise at the indoor heat exchanger is reduced.

The invention relates to the field of unmanned aerial vehicles, in particular to a tandem dual-rotor unmanned aerial vehicle structure which comprises an unmanned aerial vehicle body, a mounting plate slidably connected to the unmanned aerial vehicle body, spiral wings rotatably connected to the two ends of the unmanned aerial vehicle body and a driving device used for driving each spiral wing to rotate. The two spiral wings are located at the front end and the rear end of the unmanned aerial vehicle body correspondingly, the mounting plate slides in the width direction of the unmanned aerial vehicle body, and a plurality of mounting holes used for mounting an operation platform are formed in the mounting plate. The application has the advantages that the application range of the unmanned aerial vehicle can be widened, and the flight stability of the unmanned aerial vehicle can be guaranteed when different operation platforms are installed on the unmanned aerial vehicle.

The utility model discloses a hovercraft fan device with a pre-dust-fall function, which comprises a fan shell, a dust-fall spraying ring seat is detachably and fixedly connected to the front end part of the fan shell, and a dust-fall atomizing nozzle is fixedly connected to the inner side part of the dust-fall spraying ring seat corresponding to the circumference of the dust-fall spraying ring seat; a water supply pipe is communicated with the dust-falling atomizing nozzle through the dust-falling spraying ring seat, and a water supply pump is communicated with the water supply pipe; a first fan blade set and a second fan blade set are sequentially assembled in the fan shell, and the first fan blade set and the second fan blade set are coaxially arranged in a propeller reversing mode. The technical problems that in the prior art, dust is prone to being accumulated during operation of a fan for a hovercraft, so that the propelling efficiency and the function stability of the fan are reduced, the overall maintenance cost is increased, and the application economical efficiency is poor are solved.

The invention relates to the technical field of design of centripetal turbines of micro gas turbines, in particular to a design method for a volute and a nozzle ring of a centripetal turbine of a micro gas turbine. One-dimensional design of a volute and a nozzle ring is carried out by adopting a near-zero vortex design method, after a three-dimensional model is established, three-dimensional flow analysis and structure optimization are carried out, and the blade profile design of the nozzle ring adopts an integer operation mode in the design of an axial flow plane cascade gas turbine under the framework of the near-zero vortex design. The required annular blade grid is obtained through shape-preserving transformation, the blade profile can achieve a better pneumatic effect, and the energy conversion rate is increased; ribs are additionally arranged at an outlet in the volute design, and the problem that static strength of the volute is insufficient possibly is solved. Due to the design of the nozzle ring and the volute, the overall design requirement of the centripetal turbine of the micro gas turbine is met, the aerodynamic performance of the turbine is further improved, and the flowing loss of airflow is reduced.

The utility model relates to the field of antenna support discloses an unmanned aerial vehicle antenna support including low shelter bionical support structure, low shelter bionical support structure includes support frame, the inner wall fixedly connected with support rod of support frame, the inner wall fixedly connected with mounting rod of support frame, the bottom outer wall rotationally connected with gyroscope structure of mounting rod, the gyroscope structure includes first ring, the inner wall rotationally connected with second ring of first ring, the inner wall rotationally connected with third ring of second ring, the inner wall rotationally connected with signal receiver of third ring through pivot. In the utility model, through setting up low shelter bionical support structure, reduce the support to the signal shelter, and reduce the weight of self, through setting up gyroscope structure, realize antenna real -time attitude compensation, make signal receiver always steady point to target, solve the problem that the antenna is easy to disconnect with ground because of fuselage attitude change.

The utility model discloses a turbine rotor blade, a turbine rotor and an engine turbine, which belong to the technical field of turbine engines and are used for solving the problem of insufficient connecting strength of an extension root and a tenon caused by overweight of the turbine blade. The turbine rotor blade provided by the utility model comprises a cavity, one end, positioned at the blade tip, of the cavity is provided with an opening, and the other end of the cavity is closed; the cavity sequentially comprises a first cavity section, a second cavity section, a third cavity section and a fourth cavity section in the radial direction of the blade. The first cavity section and the second cavity section are formed in the center of the interior of the tenon; the third cavity section and the fourth cavity section are respectively arranged in the extension root and the blade body and are respectively matched with the extension root and the blade body in appearance; the chordwise width of the first cavity section and the second cavity section along the blade is smaller than the chordwise width of the third cavity section along the blade. According to the turbine rotor blade, the strength and the rigidity of the blade are effectively considered, and the overall performance of an engine turbine is improved.

Tractor (2) of a commercial vehicle (1) comprising lateral fairings (20) each having a fixed portion (21) attached to a chassis (5), a movable portion (22), and a mounting arrangement (25) to vary a fairing height of the movable portion (22) in accordance with a fifth-wheel height (Hfw) of a fifth-wheel coupling (15), wherein the mounting arrangement (25) is chosen between: - a discontinuous mounting arrangement (25) comprising a first mounting member and a series of second mounting members, the series of second mounting members comprising separate second members aligned at different mounting heights, - a continuous mounting arrangement (25) comprising a pinion and a rack configured to cooperate with each other to move the movable portion (22) with respect to the fixed portion (21) within a range of mounting heights when the pinion (30) is driven in rotation.

The invention discloses a two-section type flapping wing bionic bird which is provided with a lightweight fuselage 1, wings 2 and an empennage 3, the wings 2 are driven by a wing driving mechanism to imitate the action of flapping the wings when birds fly, and the empennage 3 is driven by an empennage driving mechanism to imitate the action of adjusting the tails when the birds fly. The two-section type flapping wing bionic bird is further provided with an electric control system module used for controlling the wing driving mechanisms and the empennage driving mechanism. The invention provides a design of a two-section type flapping wing bionic bird (aircraft) structure, the operation is convenient, the flight attitude is close to that of a normal bird, and free steering in the air can be realized. The purposes of light weight and pneumatic performance improvement are achieved, the flight maneuverability is improved, and the control convenience is further improved; due to the improvement of light weight and aerodynamic performance, the two-section type flapping wing bionic bird can be suitable for various use environments.

This invention discloses an optimization design method for S-curve nozzles used in aero-engines that considers structural deformation, belonging to the field of aero-engines. The method selects key geometric parameters of the S-curve nozzle as characteristic parameters, chooses the structural deformation value at a characteristic location and two aerodynamic performance parameters as objective functions, then conducts orthogonal experimental design and constructs a response surface model based on the characteristic parameters and objective functions. After each optimization step, a cyclical evaluation is performed to obtain the final optimization result. This invention solves the problem of high aerodynamic performance loss caused by large structural deformation in S-curve nozzles used in aero-engines in existing technologies.

The application discloses a design method of a fan blade, the fan blade, a fan and an extractor hood. The fan blade is arranged in a fan impeller. The design method comprises the following steps: taking a plane perpendicular to the rotating axis of the fan impeller as a characteristic plane, defining the blade profile of the fan blade on the characteristic plane as a characteristic curve, and the characteristic curve is a double circular arc curve; taking the blade profile of a single circular arc blade on the characteristic plane as a first circular arc of the characteristic curve, taking the inlet angle of the characteristic curve, the outlet angle of the characteristic curve and the radius of a second circular arc of the characteristic curve as three factors, obtaining a linear regression equation about the flow of the fan and a linear regression equation about the total pressure efficiency, and taking the optimal solution as the size parameter of the fan blade. The design method of the fan blade obtains the design parameters of the double circular arc curve on the basis of the current single circular arc blade, improves the internal flow state of the fan and improves the aerodynamic performance of the fan.

The invention discloses an aircraft connecting assembly and an aircraft, and relates to the technical field of aircrafts, the aircraft connecting assembly comprises a fixing shell, the fixing shell is connected with a pair of connecting rods, one side of each connecting rod is slidably connected with an inserting block, the bottom end of each connecting rod is provided with an inserting groove, and one connecting rod is internally and rotatably connected with a wind shielding cloth roll; the aircraft connecting assembly comprises a fixing shell, two pairs of connecting rods are slidably connected to the fixing shell, the connecting rods are slidably connected to a fixing frame through sliding grooves, a supporting rod is slidably connected to the fixing shell, a sliding block is slidably connected to the supporting rod, and a pull rod is rotatably connected between the sliding block and the fixing frame. The sliding block pushes the fixing frame through the pull rod, so that the two pairs of connecting rods rotate oppositely and are aligned and closed together, the two pairs of connecting rods are pulled to be slowly retracted into the two fixing shells through rotation of the lead screw, fixation is firm, looseness is not likely to happen, the wind blocking cloth roll is pulled out and unfolded during landing, and therefore wind resistance is increased and the sliding distance is reduced during landing of the unmanned aerial vehicle.