A ducted fan wind-resistant control method based on fluidic oscillator

Abstract

The application provides a ducted fan wind resistance control method based on a fluidic oscillator, comprising: obtaining a target separation line of an inner wall of a duct lip of a target ducted fan under a preset crosswind working condition; constructing a mapping relationship model among a fluidic angle, a position of a fluidic outlet relative to the target separation line, and a target influence width based on the target separation line through single-oscillator excitation experiments; according to the mapping relationship model and a preset criterion, under circumferential uniform geometric constraints, taking the fluidic position, angle, spacing, and number as coupled parameters to cooperatively solve and obtain initial arrangement parameters; taking the initial arrangement parameters as inputs, taking minimum residual overturning moment under crosswind as a target to perform multiple fine-tuning verification to output final arrangement parameters; and setting the oscillators on the target ducted fan according to the final arrangement parameters to realize adaptive wind resistance control. The application solves the problem of lacking a ducted fan wind resistance control method based on a fluidic oscillator with simple system structure, low cost, and high efficiency in the prior art.

Description

Technical Field

[0001] This invention relates to the field of wind resistance control technology, and in particular to a wind resistance control method for ducted fans based on jet oscillators. Background Technology

[0002] Ducted fans, with their advantages of high aerodynamic efficiency, high thrust density, low operating noise, and good safety, are widely used in various light power equipment such as small UAVs and vertical takeoff and landing aircraft. During actual flight, ducted fans are highly susceptible to interference from external wind fields such as crosswinds and gusts, leading to distortion of the airflow inside the duct, increased aerodynamic interference between the propeller tip vortex and the duct wall, and uneven circumferential pressure. This results in thrust loss, flight attitude deviation, and in severe cases, even loss of control. Wind resistance has become a key technical bottleneck restricting the application range of ducted fan equipment. Currently, existing wind resistance control methods for ducted fans mainly focus on passive control methods such as fan speed regulation and control surface deflection, or improving wind resistance by optimizing the duct geometry. These methods suffer from slow response, poor wind resistance adaptability, and inability to cope with complex and changing wind field interference in real time. Furthermore, most require additional electronic control components, leading to complex system structure, increased cost, and decreased reliability.

[0003] Jet oscillators, as a simple aerodynamic control element with no moving parts, have been attempted for application in the field of airflow control. However, in existing technologies, exciters are mostly driven by high-pressure air sources and are not designed to adapt to the low-pressure conditions of ducted fans; at the same time, exciters are mostly arranged independently, which cannot fully utilize their airflow regulation potential under low-pressure conditions, making it difficult to achieve efficient wind resistance control. Summary of the Invention

[0004] Therefore, the purpose of this invention is to provide a ducted fan wind resistance control method based on a jet oscillator, aiming to solve the problem in the prior art of lacking a ducted fan wind resistance control method based on a jet oscillator that has a simple system structure, low cost, and high efficiency in wind resistance.

[0005] A ducted fan wind resistance control method based on a jet oscillator according to an embodiment of the present invention includes: Obtain the target separation line of the inner wall of the duct lip of the target ducted fan under a preset crosswind condition. Based on the target separation line, construct a mapping relationship model between the jet angle and the position of the jet outlet relative to the target separation line, and the target influence width, through an excitation experiment with a single oscillator. Based on the mapping relationship model and preset criteria, and combined with the geometric constraint that the oscillators are uniformly arranged circumferentially on the inner wall of the duct lip, the jet position, jet angle, spanwise spacing and number of oscillators are used as a set of coupling parameters for collaborative solution to obtain the initial arrangement parameters. Using the initial arrangement parameters as input, and with the goal of minimizing the residual overturning moment under crosswind, multi-parameter fine-tuning verification is performed, and the final arrangement parameters of each oscillator on the target ducted fan are output. Based on the final arrangement parameters, each oscillator is set on the target ducted fan to achieve adaptive wind resistance control of the target ducted fan. The target influence width is the arc length span of the controlled separation zone induced by the jet of a single oscillator in the circumferential direction on the inner wall of the duct when the oscillator operates at a specific jet angle and jet position. The preset criterion is that the target influence widths of adjacent excitation units should maintain a preset overlap ratio.

[0006] In addition, the ducted fan wind resistance control method based on a jet oscillator according to the above embodiments of the present invention may also have the following additional technical features: Furthermore, the steps for obtaining the target separation line on the inner wall of the duct lip of the target ducted fan under preset crosswind conditions include: Under the preset crosswind conditions, the streamline map of the inner wall of the target ducted fan lip is obtained through oil flow experiments or computational fluid dynamics. The circumferential line connecting the starting positions of flow separation is extracted from the wall streamline diagram and used as the target separation line.

[0007] Furthermore, based on the excitation experiment of the target separation line using a single oscillator, the steps of constructing a mapping model between the jet angle and the position of the jet outlet relative to the target separation line, and the target influence width include: Using the target separation line as a position reference, install a single oscillator at one or more circumferential positions on the inner wall of the duct lip; By changing the jet angle of the individual oscillator and the flow direction distance of the jet outlet center relative to the target separation line, the target influence width is measured under various parameter combinations; Using the jet angle and the flow direction distance as inputs, and the target influence width as output, an interpolation table or response surface function is constructed as the mapping relationship model.

[0008] Furthermore, based on the aforementioned mapping relationship model and preset criteria, and combined with the geometric constraint of the oscillators being uniformly arranged circumferentially on the inner wall of the duct lip, the steps of obtaining the initial arrangement parameters by co-solving the jet position, jet angle, spanwise spacing, and number of oscillators as a set of coupled parameters include: Scan the jet angle and the flow direction distance within the preset jet angle range, substitute them into the mapping relationship model to obtain the corresponding target influence width, and determine the spanwise spacing by the preset overlap ratio and the target influence width; Using the relationship between the target influence width and spanwise spacing given by the mapping model, and the geometric constraints as constraints, the number of oscillators is determined according to the spanwise spacing and perimeter. Candidate parameter combinations with an integer number of oscillators are selected. The number is rounded down and the spanwise spacing is calculated. The overlap ratio is then verified to still meet the preset conditions. If so, the angle, position, spacing, and number at this time are output as the initial arrangement parameters.

[0009] Furthermore, the steps of performing multi-parameter fine-tuning verification with the initial arrangement parameters as input and the goal of minimizing the residual overturning moment under crosswinds, and outputting the final arrangement parameters of each oscillator on the target ducted fan, include: Based on the jet angle, flow distance and spanwise spacing in the initial arrangement parameters, multiple horizontal values ​​are selected near their respective initial values ​​and combined to form multiple sets of experimental parameters. Based on the experimental parameters described in multiple sets, crosswind conditions were tested in a wind tunnel using an orthogonal experimental method, and the residual overturning moment corresponding to each set of experimental parameters was measured using a six-component balance. The set of experimental parameters that minimizes the residual overturning moment is selected as the final arrangement parameters output.

[0010] Furthermore, the adaptive wind resistance control steps for the target ducted fan include: After setting each oscillator according to the final arrangement parameters, the duct fan operates, and a basic pressure difference is formed inside and outside the duct lip, driving each oscillator to self-excite and generate an unsteady jet. When a crosswind blows, the pressure difference between the inside and outside of the duct lip on the windward side increases, and the supply pressure difference received by the oscillator on the windward side increases accordingly, causing the jet intensity and frequency output by the oscillator to be adaptively enhanced, inducing controlled flow separation locally on the inner wall of the lip, generating a restoring torque opposite to the direction of the crosswind overturning moment, and achieving attitude correction. When the crosswind weakens or the airflow stabilizes, the pressure difference between the inside and outside of the duct lip on the windward side returns to normal, and the jet intensity and frequency of the oscillator adaptively decrease, returning to the basic working state.

[0011] Furthermore, the preset overlap ratio is characterized by an overlap coefficient, which is the difference between the target influence width of the previous oscillator and the spanwise spacing of the adjacent oscillators, divided by the target influence width.

[0012] Another objective of this invention is to provide a ducted fan wind resistance control system based on a jet oscillator, for implementing the aforementioned ducted fan wind resistance control method based on a jet oscillator, the system comprising: The model building module is used to obtain the target separation line of the target duct fan on the inner wall of the duct lip under a preset crosswind condition. Based on the target separation line, through an excitation experiment of a single oscillator, a mapping relationship model is constructed between the jet angle and the position of the jet outlet relative to the target separation line, and the target influence width. The target influence width is the arc length span of the controlled separation zone induced by the jet on the inner wall of the duct when the single oscillator operates at a specific jet angle and jet position. The initial parameter determination module is used to obtain the initial arrangement parameters by combining the mapping relationship model and preset criteria with the geometric constraints of the oscillators being uniformly arranged in the circumferential direction on the inner wall of the duct lip, and by using the jet position, jet angle, spanwise spacing and number of oscillators as a set of coupling parameters. The preset criteria is to maintain a preset overlap ratio between the target influence widths of adjacent excitation units. The final parameter determination module is used to perform multi-parameter fine-tuning verification with the initial arrangement parameters as input and the goal of minimizing the residual overturning moment under crosswinds, and outputs the final arrangement parameters of each oscillator on the target ducted fan, so as to set each oscillator on the target ducted fan according to the final arrangement parameters, so as to realize the adaptive wind resistance control of the target ducted fan.

[0013] Another objective of this invention is to provide a storage medium storing a computer program that, when executed by a processor, implements the steps of the above-described ducted fan wind resistance control method based on a jet oscillator.

[0014] Another objective of this invention is to provide an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of the above-described ducted fan wind resistance control method based on a jet oscillator.

[0015] Another objective of this invention is to provide a ducted fan equipped with an oscillator, wherein the oscillator is configured according to the aforementioned ducted fan wind resistance control method based on a jet oscillator.

[0016] This invention establishes a quantitative correlation between oscillator excitation parameters and their spanwise control range on the inner wall of the duct lip by obtaining the target separation line and constructing a mapping model between the jet angle, jet position, and target influence width. Based on this, and using the criterion that the spanwise influence ranges of adjacent oscillators maintain a preset overlap ratio, the jet position, jet angle, spanwise spacing, and number of oscillators are used as a set of coupling parameters for collaborative solution. This achieves an integrated arrangement design of multiple oscillators on the inner wall of the duct lip, solving the problem in existing technologies where parameters cannot be matched collaboratively when oscillators are arranged independently, making it difficult to adapt to the specific structure of the duct fan. Simultaneously, the initial arrangement parameters are fine-tuned and verified with the goal of minimizing the residual overturning moment, further ensuring the actual wind resistance effect of the arrangement scheme under crosswind conditions. This method incorporates the oscillator excitation characteristics and duct geometric constraints into a unified collaborative design framework, achieving integrated adaptation of the oscillator and duct fan without relying on a high-pressure air source or additional electrical control components. The system has a simple structure, low cost, and high wind resistance efficiency. Therefore, this invention solves the problem in the prior art of lacking a simple, low-cost, and highly efficient wind-resistant ducted fan wind-resistant control method based on jet oscillators. Attached Figure Description

[0017] Figure 1 This is a flowchart of the ducted fan wind resistance control method based on a jet oscillator in the first embodiment of the present invention; Figure 2 This is a schematic diagram of the ducted fan wind-resistant control system based on a jet oscillator in the second embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of the electronic device in the third embodiment of the present invention; The following detailed description, in conjunction with the accompanying drawings, will further illustrate the present invention. Detailed Implementation

[0018] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Several embodiments of the invention are illustrated in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0020] Example 1 Please see Figure 1 The figure shows a ducted fan wind resistance control method based on a jet oscillator in the first embodiment of the present invention, which specifically includes S01-S03.

[0021] S01, Obtain the target separation line of the inner wall of the duct lip under the preset crosswind condition. Based on the target separation line, construct a mapping relationship model between the jet angle and the position of the jet outlet relative to the target separation line, and the target influence width, through an excitation experiment of a single oscillator. The target influence width is the arc length span of the controlled separation zone induced by the jet on the inner wall of the duct when the single oscillator operates at a specific jet angle and jet position.

[0022] Specifically, under the preset crosswind condition, the streamline profile of the inner wall of the target ducted fan lip is obtained through oil flow experiments or computational fluid dynamics. The circumferential line connecting the starting positions of flow separation is extracted from the streamline profile and used as the target separation line. In practice, when using an oil flow experiment, an oil mixture (such as a mixture of titanium dioxide and kerosene) is coated on the inner wall of the duct lip. The ducted fan is started, and a preset crosswind is applied in the wind tunnel. After the oil flow pattern stabilizes, the streamline distribution on the wall is recorded. When using computational fluid dynamics, a three-dimensional model of the ducted fan is established, and steady or unsteady numerical simulations are performed under the preset crosswind condition to extract the limiting streamlines of the inner wall of the lip. The circumferential line connecting the starting positions of flow separation is extracted from the streamline profile and used as the target separation line. The target separation line serves to provide a unified circumferential reference for the positioning of the jet outlet in subsequent single-oscillator excitation experiments, ensuring that the mapping model accurately reflects the influence of the excitation position on the spanwise control range.

[0023] Additionally, using the target separation line as a positional reference, one or more individual oscillators are installed at selected circumferential positions on the inner wall of the duct lip; the jet angle and the flow distance of the jet outlet center relative to the target separation line are changed, and the target influence width is measured under various parameter combinations; using the jet angle and the flow distance as inputs, and the target influence width as output, an interpolation table or response surface function is constructed as the mapping relationship model. In specific implementation, the jet angle, i.e. , is the angle between the jet centerline and the local mainstream direction, with a recommended range of 40° to 80°, and the flow direction distance, i.e. Based on the characteristic scale of the jet outlet, i.e. Dimensionless transformation is performed, and the dimensionless flow direction distance is defined as follows: The characteristic scale is the narrow side height of the rectangular outlet or the diameter of the circular outlet. Multiple sampling points are selected within the parameter space of jet angle and flow direction distance; for example, jet angles of 40°, 50°, 60°, 70°, and 80°, and flow direction distances of 0, 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0, forming a parameter combination matrix. Under each parameter combination, the circumferential boundary of the controlled separation zone is measured using wall streamline maps or particle image velocimetry to obtain the corresponding target influence width, i.e. And calculate the dimensionless target influence width. Using the jet angle and dimensionless flow direction distance as inputs, and the dimensionless target influence width as output, an interpolation table or response surface function is constructed as the mapping relationship model. This mapping relationship model is used to quantitatively characterize the impact of excitation parameter changes on the spanwise control range, providing a calculation basis for directly obtaining the corresponding dimensionless target influence width from any set of jet angle and flow direction distance parameters in the collaborative solution step, avoiding the tedious process of having to re-experiment every time the parameters are adjusted. Simultaneously, the dimensionless processing frees the model from dependence on specific feature scales, allowing it to be extended to ducted fan configurations of different sizes.

[0024] S02, based on the mapping relationship model and preset criteria, and combined with the geometric constraints of the oscillators being uniformly arranged circumferentially on the inner wall of the duct lip, the jet position, jet angle, spanwise spacing and number of oscillators are used as a set of coupling parameters for collaborative solution to obtain the initial arrangement parameters. The preset criteria is to maintain a preset overlap ratio between the target influence widths of adjacent excitation units.

[0025] In practical implementation, based on the mapping relationship model, four parameters—jet position, jet angle, spanwise spacing, and number of oscillators—are incorporated into a unified coupled solution framework to avoid local optima problems caused by step-by-step isolated optimization. A preset criterion ensures that the spanwise control range of adjacent oscillators neither produces uncovered strips nor causes vorticity accumulation due to excessive overlap, leading to a decrease in control efficiency.

[0026] Specifically, the collaborative solution steps include: scanning the jet angle and the flow direction distance within a preset jet angle range; substituting these into the mapping relationship model to obtain the corresponding target influence width; and determining the spanwise spacing based on the preset overlap ratio and the target influence width; using the relationship between the target influence width and the spanwise spacing given by the mapping relationship model, as well as the geometric constraints, as constraints; determining the number of oscillators based on the spanwise spacing and perimeter; selecting candidate parameter combinations where the number of oscillators is an integer; rounding the number and then calculating the spanwise spacing; and verifying whether the overlap ratio still meets the preset conditions. If so, the angle, position, spacing, and number at this point are output as the initial arrangement parameters. The preset overlap ratio is characterized by an overlap coefficient, which is the difference between the target influence width of the previous oscillator and the spanwise spacing of the adjacent oscillators, divided by the target influence width. In specific implementation, the jet angle and dimensionless flow direction distance are scanned within a preset jet angle range of 40° to 80°, substituting them into the mapping relationship model to obtain the dimensionless target influence width, and then restoring it to a dimensional target influence width based on the characteristic scale. Overlap coefficient, i.e. Defined as The recommended value range is 10% to 25%, with an initial value of 15% being preferred. (Using the formula...) Calculate the spanwise spacing, i.e. The circumference is obtained from the inner diameter of the duct, and the number of oscillators is calculated. Where D is the inner diameter of the duct, combinations of oscillators with an integer or near-integer number are selected, and the spanwise spacing is calculated after rounding the number. Then, it is verified whether the overlap ratio at this point meets the requirement of 10%–25%.

[0027] Furthermore, the preset overlap ratio is characterized by an overlap coefficient, which is the difference between the target influence width of the previous oscillator and the spanwise spacing of the adjacent oscillators, divided by the target influence width.

[0028] In practical implementation, the overlap coefficient, i.e. The value of is determined by: when When the overlap is less than 10%, the small overlap between adjacent spanwise control areas may lead to uncontrolled stripes in the circumferential cover, reducing wind resistance; when When the vortex overlaps to >25%, the induced separation zone vortex system overlaps excessively, generating disturbances that are detrimental to the control effect and increasing the system complexity. Taking 15% can achieve a good balance between coverage continuity and control efficiency.

[0029] S03, using the initial arrangement parameters as input, perform multi-parameter fine-tuning verification with the goal of minimizing the residual overturning moment under crosswind, and output the final arrangement parameters of each oscillator on the target ducted fan. Based on the final arrangement parameters, set each oscillator on the target ducted fan to achieve adaptive wind resistance control of the target ducted fan.

[0030] This step uses the initial layout parameters as a benchmark and compensates for the deviation between the model and the actual working conditions through a small number of verification experiments to ensure that the final solution has the best wind resistance effect under real crosswind conditions.

[0031] Specifically, based on the jet angle, flow distance, and spanwise spacing in the initial arrangement parameters, multiple horizontal values ​​are selected near their respective initial values ​​to form multiple sets of experimental parameters. Based on these multiple sets of experimental parameters, an orthogonal experimental method is used to conduct crosswind experiments in a wind tunnel, and a six-component balance is used to measure the residual overturning moment corresponding to each set of experimental parameters. The set of experimental parameters that minimizes the residual overturning moment is selected as the final arrangement parameter output. In specific implementation, based on the jet angle, dimensionless flow distance, and spanwise spacing in the initial arrangement parameters, the jet angle is set with a step size of ±5°, the dimensionless flow distance with a step size of ±0.2, and the spanwise spacing with a step size of ±(0.2·d). Each factor has 2-3 levels. An orthogonal experimental matrix is ​​designed using the orthogonal experimental method. For example, for three factors and three levels, an L9(3³) orthogonal array can be used, resulting in a total of 9 sets of experiments. A preset crosswind condition is applied in the wind tunnel, and the overturning moment under each set of experimental parameters is measured using a six-component balance. The residual overturning moment is calculated as the response index, and the set that minimizes the residual overturning moment is selected as the final layout parameter output. This allows for the coverage of the multi-factor parameter space with the fewest number of experiments, and rapid convergence to the globally optimal layout.

[0032] Furthermore, after setting each oscillator according to the final arrangement parameters, the duct fan operates, creating a basic pressure difference inside and outside the duct lip, driving each oscillator to self-excite and generate unsteady jets. When a crosswind blows, the pressure difference inside and outside the duct lip on the windward side increases, and the air supply pressure difference received by the corresponding oscillator on the windward side increases accordingly, causing the jet intensity and frequency output by the oscillator to adaptively increase. This induces controlled flow separation locally on the inner wall of the lip, generating a restoring torque opposite to the crosswind overturning moment, thus achieving attitude correction. When the crosswind weakens or the airflow stabilizes, the pressure difference inside and outside the duct lip on the windward side returns to normal, and the jet intensity and frequency of the oscillator adaptively decrease, returning to the basic operating state. In practical implementation, since the air supply of the oscillator depends entirely on the pressure difference inside and outside the duct lip, no external high-pressure air source or electronic control adjustment components are required. The stronger the wind field interference, the greater the pressure difference on the windward side, and the more adaptively the oscillator jet intensity increases. This has the advantages of rapid response, simple structure, and maintenance-free operation. Furthermore, it can maintain its working state even when the flight control or power supply fails, thus improving the fault tolerance of the aircraft.

[0033] In summary, this invention establishes a quantitative correlation between oscillator excitation parameters and their spanwise control range on the duct inner wall by obtaining the target separation line on the inner wall of the duct and constructing a mapping model between the jet angle, jet position, and target influence width. Based on this, and using the criterion that the spanwise influence ranges of adjacent oscillators must maintain a preset overlap ratio, the jet position, jet angle, spanwise spacing, and number of oscillators are used as a set of coupling parameters for collaborative solution. This achieves an integrated arrangement design of multiple oscillators on the inner wall of the duct lip, solving the problem in existing technologies where parameters cannot be matched collaboratively when oscillators are arranged independently, making it difficult to adapt to the specific structure of the duct fan. Simultaneously, the initial arrangement parameters are fine-tuned and verified with the goal of minimizing the residual overturning moment, further ensuring the actual wind resistance effect of the arrangement scheme under crosswind conditions. This method incorporates the oscillator excitation characteristics and duct geometric constraints into a unified collaborative design framework, achieving integrated adaptation of the oscillator and duct fan without relying on a high-pressure air source or additional electrical control components. The system structure is simple, low-cost, and highly efficient in wind resistance. Therefore, this invention solves the problem in the prior art of lacking a simple, low-cost, and highly efficient wind-resistant ducted fan wind-resistant control method based on jet oscillators.

[0034] Example 2 Please see Figure 2 The diagram shown is a structural block diagram of the ducted fan wind-resistant control system based on a jet oscillator proposed in the second embodiment of the present invention. This ducted fan wind-resistant control system 200 based on a jet oscillator includes: a model building module 21, an initial parameter determination module 22, and a final parameter determination module 23, wherein: Model building module 21 is used to obtain the target separation line of the target duct fan under a preset crosswind condition, and to build a mapping relationship model between the jet angle and the position of the jet outlet relative to the target separation line and the target influence width based on the excitation experiment of a single oscillator through the target separation line. The target influence width is the arc length span of the controlled separation zone induced by the jet on the inner wall of the duct when the single oscillator works at a specific jet angle and jet position. The initial parameter determination module 22 is used to obtain the initial arrangement parameters by combining the mapping relationship model and preset criteria, and the geometric constraints of the oscillators being uniformly arranged in the circumferential direction on the inner wall of the duct lip, with the jet position, jet angle, spanwise spacing and number of oscillators as a set of coupling parameters. The preset criteria is to maintain a preset overlap ratio between the target influence widths of adjacent excitation units. The final parameter determination module 23 is used to perform multi-parameter fine-tuning verification with the initial arrangement parameters as input and the goal of minimizing the residual overturning moment under crosswinds, and outputs the final arrangement parameters of each oscillator on the target ducted fan, so as to set each oscillator on the target ducted fan according to the final arrangement parameters, so as to realize the adaptive wind resistance control of the target ducted fan.

[0035] Example 3 In another aspect, the present invention also proposes an electronic device, please refer to [link to relevant documentation]. Figure 3 The diagram shows an electronic device according to the third embodiment of the present invention, including a memory 20, a processor 10, and a computer program 30 stored in the memory and executable on the processor. When the processor 10 executes the computer program 30, it implements the ducted fan wind resistance control method based on the jet oscillator as described above.

[0036] In some embodiments, the processor 10 may be a central processing unit (CPU), controller, microcontroller, microprocessor or other data processing chip, used to run program code stored in memory 20 or process data, such as executing access restriction programs.

[0037] The memory 20 includes at least one type of readable storage medium, such as flash memory, hard disk, multimedia card, card-type memory (e.g., SD or DX memory), magnetic memory, magnetic disk, optical disk, etc. In some embodiments, the memory 20 can be an internal storage unit of an electronic device, such as the hard disk of the electronic device. In other embodiments, the memory 20 can also be an external storage device of the electronic device, such as a plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, etc. Furthermore, the memory 20 can include both internal and external storage units of the electronic device. The memory 20 can be used not only to store application software and various types of data of the electronic device, but also to temporarily store data that has been output or will be output.

[0038] It should be pointed out that, Figure 3 The structure shown does not constitute a limitation on the electronic device. In other embodiments, the electronic device may include fewer or more components than shown, or combine certain components, or have different component arrangements.

[0039] This invention also proposes a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described ducted fan wind resistance control method based on a jet oscillator.

[0040] This invention also proposes a ducted fan, which is equipped with an oscillator, and the oscillator is configured according to the above-described ducted fan wind resistance control method based on jet oscillator.

[0041] Those skilled in the art will understand that the logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can mean any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device.

[0042] More specific examples of computer-readable media (a non-exhaustive list) include: electrical connections (electronic devices) having one or more wires, portable computer disk drives (magnetic devices), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Furthermore, computer-readable media can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in computer memory.

[0043] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0044] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0045] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A ducted fan wind resistance control method based on a jet oscillator, characterized in that, The method includes: Obtain the target separation line of the duct lip inner wall under a preset crosswind condition. Based on the target separation line, construct a mapping model between the jet angle and the position of the jet outlet relative to the target separation line, and the target influence width, through an excitation experiment with a single oscillator. The target influence width is the circumferential arc length span of the controlled separation zone induced by the jet on the inner wall of the duct when the single oscillator operates at a specific jet angle and jet position. Based on the mapping relationship model and preset criteria, and combined with the geometric constraint that the oscillators are uniformly arranged circumferentially on the inner wall of the duct lip, the jet position, jet angle, spanwise spacing and number of oscillators are used as a set of coupling parameters for collaborative solution to obtain the initial arrangement parameters. The preset criteria is that the target influence width between adjacent excitation units maintains a preset overlap ratio. Using the initial arrangement parameters as input, and with the goal of minimizing the residual overturning moment under crosswind, multi-parameter fine-tuning verification is performed, and the final arrangement parameters of each oscillator on the target ducted fan are output. Based on the final arrangement parameters, each oscillator is set on the target ducted fan to achieve adaptive wind resistance control of the target ducted fan. Based on the mapping relationship model and preset criteria, and combined with the geometric constraint of the oscillators being uniformly arranged circumferentially on the inner wall of the duct lip, the steps to obtain the initial arrangement parameters by co-solving the jet position, jet angle, spanwise spacing, and number of oscillators as a set of coupled parameters include: Scan the jet angle and flow direction distance within the preset jet angle range, substitute them into the mapping relationship model to obtain the corresponding target influence width, and determine the spanwise spacing by the preset overlap ratio and the target influence width, wherein the flow direction distance is the distance between the jet outlet center of the oscillator and the target separation line; Using the relationship between the target influence width and spanwise spacing given by the mapping model, and the geometric constraints as constraints, the number of oscillators is determined according to the spanwise spacing and perimeter. Candidate parameter combinations with an integer number of oscillators are selected. The number is rounded down and the spanwise spacing is calculated. The overlap ratio is then verified to still meet the preset conditions. If so, the angle, position, spacing, and number at this time are output as the initial arrangement parameters.

2. The ducted fan wind resistance control method based on jet oscillator according to claim 1, characterized in that, The steps for obtaining the target separation line of the duct lip inner wall of the target ducted fan under preset crosswind conditions include: Under the preset crosswind conditions, the streamline map of the inner wall of the target ducted fan lip is obtained through oil flow experiments or computational fluid dynamics. The circumferential line connecting the starting positions of flow separation is extracted from the wall streamline diagram and used as the target separation line.

3. The ducted fan wind resistance control method based on jet oscillator according to claim 1, characterized in that, The steps for constructing a mapping model between the jet angle and the position of the jet outlet relative to the target separation line, and the target influence width, based on the excitation experiment of the target separation line through a single oscillator, include: Using the target separation line as a position reference, install a single oscillator at one or more circumferential positions on the inner wall of the duct lip; By changing the jet angle of the individual oscillator and the flow direction distance of the jet outlet center relative to the target separation line, the target influence width is measured under various parameter combinations; Using the jet angle and the flow direction distance as inputs, and the target influence width as output, an interpolation table or response surface function is constructed as the mapping relationship model.

4. The ducted fan wind resistance control method based on a jet oscillator according to claim 3, characterized in that, The steps of performing multi-parameter fine-tuning verification with the initial arrangement parameters as input and the goal of minimizing the residual overturning moment under crosswinds, and outputting the final arrangement parameters of each oscillator on the target ducted fan, include: Based on the jet angle, the flow direction distance and the spanwise spacing in the initial arrangement parameters, multiple horizontal values ​​are selected near their respective initial values ​​and combined to form multiple sets of experimental parameters. Based on the experimental parameters described in multiple sets, crosswind conditions were tested in a wind tunnel using an orthogonal experimental method, and the residual overturning moment corresponding to each set of experimental parameters was measured using a six-component balance. The set of experimental parameters that minimizes the residual overturning moment is selected as the final arrangement parameters output.

5. The ducted fan wind resistance control method based on jet oscillator according to claim 1, characterized in that, The steps of adaptive wind resistance control for the target ducted fan include: After setting each oscillator according to the final arrangement parameters, the duct fan operates, and a basic pressure difference is formed inside and outside the duct lip, driving each oscillator to self-excite and generate an unsteady jet. When a crosswind blows, the pressure difference between the inside and outside of the duct lip on the windward side increases, and the supply pressure difference received by the oscillator on the windward side increases accordingly, causing the jet intensity and frequency output by the oscillator to be adaptively enhanced, inducing controlled flow separation locally on the inner wall of the lip, generating a restoring torque opposite to the direction of the crosswind overturning moment, and achieving attitude correction. When the crosswind weakens or the airflow stabilizes, the pressure difference between the inside and outside of the duct lip on the windward side returns to normal, and the jet intensity and frequency of the oscillator adaptively decrease, returning to the basic working state.

6. The ducted fan wind resistance control method based on a jet oscillator according to claim 1, characterized in that, The preset overlap ratio is characterized by an overlap coefficient, which is the difference between the target influence width of the preceding oscillator and the spanwise spacing of the adjacent oscillators, divided by the target influence width.

7. A ducted fan wind-resistant control system based on a jet oscillator, characterized in that, For implementing the ducted fan wind resistance control method based on a jet oscillator according to any one of claims 1 to 6, the system comprises: The model building module is used to obtain the target separation line of the duct lip inner wall under the preset crosswind conditions. Based on the target separation line, through the excitation experiment of a single oscillator, a mapping relationship model is constructed between the jet angle and the position of the jet outlet relative to the target separation line, and the target influence width. The target influence width is the arc length span of the controlled separation zone induced by the jet on the inner wall of the duct when the single oscillator works at a specific jet angle and jet position. The initial parameter determination module is used to obtain the initial arrangement parameters by combining the mapping relationship model and preset criteria with the geometric constraints of the oscillators being uniformly arranged in the circumferential direction on the inner wall of the duct lip, and by using the jet position, jet angle, spanwise spacing and number of oscillators as a set of coupling parameters. The preset criteria is to maintain a preset overlap ratio between the target influence widths of adjacent excitation units. The final parameter determination module is used to perform multi-parameter fine-tuning verification with the initial arrangement parameters as input and the goal of minimizing the residual overturning moment under crosswinds, and outputs the final arrangement parameters of each oscillator on the target ducted fan, so as to set each oscillator on the target ducted fan according to the final arrangement parameters, so as to realize the adaptive wind resistance control of the target ducted fan.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by the processor, it implements the steps of the ducted fan wind resistance control method based on a jet oscillator as described in any one of claims 1 to 6.

9. A ducted fan, characterized in that, The ducted fan is equipped with an oscillator, which is configured according to the ducted fan wind resistance control method based on a jet oscillator as described in any one of claims 1-6.

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