9results about How to "Improve aerodynamics" patented technology

A self-adaptive control method of an aircraft wing and the aircraft wing wherein the self-adaptive control method comprises: constructing a prediction model, inputting a real-time external aerodynamic disturbance parameter to the prediction model, predicting a predicted disturbance error at a next moment, and realizing feedforward prediction compensation of external aerodynamic disturbance. The influence of predictable disturbance on the airfoil profile is eliminated in advance; and then monitoring the airfoil pose to obtain tracking airfoil parameters, and carrying out deviation calculation on the tracking airfoil parameters and the target airfoil parameters to obtain an actual tracking error so as to provide a real-time airfoil pose feedback signal. And finally, the control assembly generates a control instruction based on the predicted disturbance error, the actual tracking error and the target airfoil profile parameter, the control instruction acts on the mechanical neural network to realize adaptive adjustment of the airfoil profile, and the airfoil profile continuously approaches the target airfoil profile neighborhood through a feedforward and feedback composite control mechanism.

The application relates to an aerodynamic profile suitable for a wind tunnel and a design method thereof, and belongs to the technical field of aviation aerodynamic wind tunnel tests. The front end surface of the aerodynamic profile is a square section, the rear end surface of the aerodynamic profile is a circular section, the middle part of the aerodynamic profile is a transition section, and the front and rear sections are connected through the change of the section shape from front to back. The research and development purpose is to provide a novel aerodynamic profile design method for the transition from a square section to a circular section, the flow field can be smoothly transitioned from a square to a circle, the influence on the flow field quality is minimized, the pressure loss is reduced, and the method of rounding the right angle and gradually increasing the rounding radius is adopted to realize the smooth transition from the square section to the circular section. The circular arc curve is gradually lengthened, the right angle side is gradually shortened, and finally the profile line is completely changed into a circular shape. The transition mode is natural and smooth, the change is gentle, the aerodynamic performance is good, and the interference on the flow field due to the change of the section shape can be obviously reduced.

This utility model belongs to the field of amphibious unmanned surface vessels (USVs), specifically relating to a folding airfoil sail amphibious USV. It includes a base, with a hydraulic telescopic rod at the upper end of the base, a mast at the upper end of the hydraulic telescopic rod, an upper sail on the upper outer side of the mast, a lower sail on the lower outer side of the mast, and a stepper motor at the upper end of the mast. This utility model features a unique folding mechanism, allowing the sail to be folded and stored when not in use. This not only improves the portability and storage efficiency of the equipment but also reduces wind and water resistance in adverse weather conditions or when underwater operations are required, lowering the risk of equipment damage. Using a symmetrical airfoil sail maintains good aerodynamic performance under different wind directions and angles, providing stable and continuous aerodynamic propulsion. This design not only improves wind energy utilization efficiency but also enhances the USV's adaptability to complex and changing environmental conditions.

The backward centrifugal wind wheel comprises a wheel cover, a wheel disc and a plurality of blades, and the blades are arranged between the wheel cover and the wheel disc at equal intervals; an air inlet is formed in the center of the wheel cover; an air outlet is formed between adjacent blades; the wheel disc comprises a wheel disc center part and a plurality of wheel disc wing parts, and a hollow part is formed between every two adjacent wheel disc wing parts; the blade top is connected with the wheel cover, the blade front edge is close to the air inlet, the blade tail edge is close to the air outlet, and the blade roots of the blades are connected with the wheel disc wing parts in a one-to-one correspondence mode. Under the axial projection of the wind wheel, the projection area of the hollow part and the projection area of the air inlet are at least partially overlapped. The hollow part is ingeniously arranged on the wheel disc, on one hand, the problems that a traditional integrally-formed wind wheel is difficult to demould and a mould is complex are solved, and low-cost and high-efficiency integrated production is achieved; and on the other hand, the excellent wing-shaped design of the blades is reserved, it is ensured that the wind wheel has excellent aerodynamic performance, and the dual requirements for efficient production and excellent performance of the backward centrifugal wind wheel in the field are really met.

This invention discloses a variable center of gravity twin-arm aircraft with a rectified wing and its control method, belonging to the field of low-altitude unmanned aerial vehicle (UAV) technology. The aircraft has only two supporting arms, front and rear. The ends of the arms are equipped with fixed-pitch propeller power units without variable pitch structures. Each arm has an independently driven, fully movable rectified wing hinged below it. The aircraft has no external tail or various independent control surfaces. The rectified wing integrates multiple functions, including airflow rectification, counteracting propeller anti-torque, dynamically adjusting the aircraft's center of gravity, and outputting attitude torque. The hardware of this invention relies on the lift difference between the two propellers and the synchronous or differential deflection of the two wings to coordinate and control the flight attitude. The control method enables vertical takeoff and landing, forward and backward level flight, lateral translation, and stationary spin flight in all attitudes. This invention features fewer structural components and lower manufacturing costs. The streamlined wing effectively reduces aerodynamic drag and increases cruising speed. It avoids the drawbacks of complex pitch control mechanisms in helicopters and redundant frames in multi-rotor aircraft. It offers flexible vertical takeoff and landing capabilities and can be widely used in various fields such as aerial photography, plant protection, surveying and mapping, and low-altitude inspection. It solves the technical pain points of existing aircraft in achieving low cost, high speed, and omnidirectional maneuverability.

The invention discloses a predetermined time adaptive control method for a wing-riding separation variant gliding aircraft, and the method specifically comprises the following steps: firstly, constructing a time scale function, and effectively avoiding the problems of unlimited increase of control quantity and singularity; secondly, designing a preset time sliding mode surface based on the time scale function; thirdly, providing a neural network parameter identification strategy, and converting a system identification problem into a parameter estimation problem so as to adapt to a flight scene with uncertain aerodynamic parameters; and finally, designing a preset time self-adaptive sliding mode controller, and realizing convergence in specified time under the condition of ensuring that the system state is not dependent on an initial condition. The adaptive gain of the controller can be dynamically adjusted according to the system environment, jitter can be inhibited, tracking errors can be reduced, and the influence caused by centralized uncertainty can be weakened; in conclusion, the control method not only realizes accurate attitude tracking, but also achieves preset time convergence characteristics irrelevant to initial conditions and control parameters, and has excellent quick responsiveness, stability and robustness.

The application discloses a kind of blade aerodynamic-structure multidisciplinary optimization design method and system based on turbulent flow discrete companion method and equivalent stress model.The method comprises the following steps: constructing the equivalent stress model of blade, calculating the maximum equivalent stress of blade using the equivalent stress model;According to the maximum equivalent stress of blade, set the objective function of aerodynamic-structure multidisciplinary optimization design;Based on turbulent flow discrete companion method, the design variables of blade are optimized, so that the objective function reaches minimum value, and the optimized blade shape is obtained according to the design variables of blade.The application can significantly improve the aerodynamic performance of blade, reduce the maximum structural stress, has the characteristics such as high efficiency and high precision, and can be widely applied to the aerodynamic-structure multidisciplinary optimization design problem of blade.

According to the improvement scheme of the file 2021102473141, left-right convection impact energy of fluid on the two sides of the stern is obtained through the upper inclined face and the lower inclined face of the stern to obtain power assisting force, resistance is reduced, energy is saved, consumption is reduced, and the speed is increased; water cannot enter the ship when the ship wall does not have a drain opening and swings left and right greatly, the ship bottom drain cylinder is arranged on the central axis, only drains water and cannot enter the ship, the ship bottom drain cylinder is provided with draft scales, sailors can observe the real-time draft depth conveniently, and the wind-resistant, wave-resistant and left-right-swing-resistant capacity is high. The bow is provided with an anti-collision rod, so that the safety is high. The anti-collision rod is divided into an upper section and a lower section, and an air duct of a bow pneumatic device is arranged in the middle; the pneumatic device provides power and accelerates flowing of gas at the bow so as to reduce pressure and drag. A low-pressure area is formed behind the anti-collision rod together with the tip circle of the prow, and water and air resistance is reduced.

The invention relates to the technical field of aerodynamic optimization of wind turbine airfoils, and particularly discloses an airfoil coupling optimization method based on vortex generator flow control and molded line optimization, which comprises the following steps: S1, determining design variables and corresponding value ranges according to task requirements, and generating an initial sample point set; s2, generating airfoil geometry according to the initial sample point set; s3, performing CFD simulation on each airfoil geometry to obtain a training data set; step S4, constructing a Kriging agent model based on the training data set; s5, taking the Kriging agent model as a fitness evaluation function, and performing global optimization search in the budget design space by adopting a particle swarm optimization algorithm to obtain an optimal design parameter combination; s6, CFD verification is conducted on the optimal design parameter combination, and the optimal design parameter combination with the verification result meeting the preset precision and performance requirements serves as a final scheme to be output. According to the method, the limitation that airfoil optimization and VG flow control are mutually independent and a synergistic effect is not considered is solved.