Laminar / turbulent friction integrated control device and method based on micro-blowing surface

Abstract

The present invention relates to the technical field of aircraft wall friction resistance control, and discloses a laminar / turbulent friction resistance integrated control device and method based on a micro-blowing surface. Multiple components of the control device work together to intelligently adjust the opening and closing of the micro-blowing unit under laminar or turbulent conditions, and dynamically adjust the working mode of the micro-blowing unit by real-time monitoring the boundary layer state of the aircraft surface. Under laminar conditions, the micro-blowing unit does not generate micro-blowing, and reduces drag through the porous surface; under turbulent conditions, the micro-blowing unit generates micro-blowing, and isolates the turbulent structure from the wall through micro-airflow, thereby reducing turbulent friction. Through this intelligent adjustment, the system can optimize the drag performance according to the actual flight environment, thereby improving flight efficiency and saving energy.

Description

Technical Field

[0001] The present invention relates to the technical field of aircraft wall friction resistance control, and in particular to a laminar / turbulent friction resistance integrated control device and method based on a micro-blowing surface. Background Art

[0002] When an aircraft flies in the atmosphere, a thin (millimeter-level) air adhesion layer will form on its surface, called the boundary layer. In the boundary layer, the air velocity changes rapidly from the relative wall static at the bottom of the boundary layer to the free flow velocity of the outer layer, resulting in strong velocity shear, which in turn generates friction resistance on the wall, i.e., friction drag. As the air moves downstream from the head of the aircraft, unstable disturbance waves will be generated in the boundary layer. The amplitude of these disturbance waves will gradually increase, forming flow structures with limited amplitudes downstream of the boundary layer, such as strips and hairpin vortices. These structures will distort the originally smooth boundary layer, making it more unstable, resulting in secondary instability of the flow and fragmentation of the flow structure, and finally turning into a turbulent state. Once the boundary layer flow enters the turbulent state, its wall friction will increase sharply, usually up to 3 to 5 times the friction of the laminar boundary layer.

[0003] Since the principles of drag reduction in laminar boundary layer and turbulent boundary layer are different, it is difficult to achieve simultaneous control of laminar / turbulent boundary layer friction with a single control method. However, when an actual aircraft is flying in the atmosphere, due to changes in its flight attitude, speed, and altitude, the flow state of its surface boundary layer is usually dynamically changing. It can be full laminar, full turbulent, or a mixture of laminar and turbulent, and a mixture of laminar and turbulent is a more common state. At present, all single friction control methods for laminar or turbulent flow, if installed on an aircraft, will only work effectively in some states, so there are great limitations. Summary of the invention

[0004] The purpose of the present invention is to provide a laminar / turbulent friction integrated control device and method based on a micro-blowing surface to address the above-mentioned problems, in order to improve the problem in the prior art that a single drag reduction control method is difficult to achieve simultaneous control of laminar / turbulent boundary layer friction and has great limitations.

[0005] The technical solution adopted by the present invention is as follows: a laminar / turbulent friction integrated control device and method based on the micro-blowing surface, wherein multiple components of the control device work in coordination, intelligently adjust the opening and closing of the micro-blowing unit in the laminar or turbulent state, and dynamically adjust the working mode of the micro-blowing unit by real-time monitoring the boundary layer state (laminar or turbulent) on the surface of the aircraft. In the laminar state, the micro-blowing unit does not generate micro-blowing, and reduces drag through the porous surface; in the turbulent state, the micro-blowing unit generates micro-blowing, and isolates the turbulent structure at the bottom of the boundary layer from the wall through the micro-airflow, thereby reducing turbulent friction. Through this intelligent adjustment, the system can optimize the drag performance according to the actual flight environment, thereby improving flight efficiency and saving energy.

[0006] In order to enable the aircraft to work effectively in both laminar and turbulent states, various components are integrated into one device, a laminar / turbulent friction integrated control device based on the micro-blowing surface, multiple components of the control device work together to intelligently adjust the closing and opening of the micro-blowing unit in laminar and turbulent states, and the control device specifically includes a micro-blowing surface, a high-frequency pressure pulsation sensor, a high-pressure gas storage tank, a control chip and a control valve; the micro-blowing surface is the control excitation unit of the control device, the micro-blowing surface is connected to the control chip and the control valve, the high-frequency pressure pulsation sensor is a pressure pulsation detection sensor, and the high-frequency pressure pulsation sensor is arranged on the micro-blowing surface Inside the surface, the high-frequency pressure pulsation sensor is used to transmit the monitored pressure pulsation timing signal to the control chip in real time for boundary layer laminar / turbulent flow state analysis; the high-pressure gas tank is connected to the micro-blowing surface through a control valve, and the high-pressure gas tank is used to provide a high-pressure gas source for the micro-blowing surface; the control chip is connected to the high-frequency pressure pulsation sensor, and the boundary layer flow state is judged by reading the high-frequency pressure pulsation signal measured in real time by the high-frequency pressure pulsation sensor, and the opening and closing command signal is transmitted to the control valve according to the judgment result; the control valve is connected to the micro-blowing surface, the control chip and the high-pressure gas tank, and the high-pressure gas source of the high-pressure gas tank is controlled by the opening and closing of the control valve.

[0007] Furthermore, in order to better adjust the air flow speed and stability, ensure the stability of the air flow and adapt to the needs of different flow states, the micro-blowing surface is configured as a sandwich composite structure, which is divided into three layers: upper, middle and lower; the upper layer is a uniformly distributed circular hole layer; the middle layer is a buffer layer, which is composed of a low permeability material and is used to adjust the seepage rate; the lower layer is an air retention chamber, which is connected to a high-pressure gas storage tank through a control valve, and a high-pressure gas source in the high-pressure gas storage tank enters the micro-blowing surface through the air retention chamber, and the high-pressure gas source forms a stable gas layer at the bottom of the air retention chamber.

[0008] It should be noted that the circular hole layer can be processed by laser drilling, with the hole diameter being on the order of tens of microns and the depth being on the order of several millimeters.

[0009] Furthermore, in order to improve control efficiency and accuracy, the micro-blowing surface is installed in a distributed manner to improve the flexibility of friction control, and the micro-blowing surface is divided into areas. Each micro-blowing surface is provided with a high-frequency pressure pulsation sensor, and each micro-blowing surface area and the high-frequency pressure pulsation sensor in its area constitute a basic control unit. According to the division of the micro-blowing surface areas, multiple basic control units are provided, and multiple basic control units share a control chip.

[0010] Furthermore, in the basic control unit, a high-frequency pressure pulsation sensor is used as a signal detection input, and a micro-blowing surface is used as a control excitation output.

[0011] A further technical solution is to dynamically adjust the working mode of the micro-blowing unit by real-time monitoring of the boundary layer state (laminar or turbulent) on the aircraft surface. Through this method of intelligent adjustment, the system can optimize the drag performance according to the actual flight environment, thereby improving flight efficiency and saving energy.

[0012] An integrated control method for laminar / turbulent friction resistance based on a micro-blowing surface, the control method comprising: starting the device, providing an air source through a high-pressure gas tank; initializing the system to ensure that each component of the device can work normally; pressure signal acquisition and flow state analysis, a high-frequency pressure pulsation sensor monitors the pressure pulsation signal on the surface of the aircraft in real time, the signal is transmitted to the control chip in a time sequence, the control chip determines the flow state of the boundary layer by analyzing the received pressure pulsation signal; judging the flow state and control decision, making a decision on whether to start micro-blowing according to the analysis result of the control chip; continuous monitoring and adjustment, the system continuously monitors the state change of the boundary layer through a high-frequency pressure pulsation sensor; when the flight mission ends or the system enters the standby state, the micro-blowing unit is closed to stop the infiltration of airflow.

[0013] Furthermore, the control chip determines the flow state of the boundary layer according to the received pressure pulsation signal, which is specifically: laminar state: if the signal indicates that the boundary layer is in a laminar state, the pressure pulsation signal is stable and has no violent fluctuations, and there are no or only a limited number of isolated dominant frequency signals in the frequency domain; turbulent state: if the signal indicates that the boundary layer is in a turbulent state, the pressure pulsation signal has strong irregular pulsations, and there are a series of continuous frequency signals in the frequency domain, which conforms to the law of turbulent energy spectrum.

[0014] Furthermore, the flow state judgment and control decision specifically include the following steps: in the laminar flow state: the control chip sends a closing command to the control valve, the micro-blowing unit turns off the blowing, and the circular hole layer on the micro-blowing surface does not generate airflow; in the turbulent flow state, the control chip sends an opening command to the control valve, the control valve opens, the micro-blowing unit turns on the blowing, and the high-pressure air source flows into the air chamber through the control valve, and forms a tiny airflow through the buffer layer and the circular hole layer, which seeps out perpendicular to the surface of the aircraft.

[0015] Furthermore, in order to ensure that the aircraft always maintains the best resistance characteristics during flight, the continuous monitoring and adjustment includes the following steps: the control chip processes the pressure pulsation signal in real time, dynamically judges the state of the aircraft surface, and adjusts the working state of the micro-blowing unit according to the state of the aircraft surface; the micro-blowing unit switches the working state to open or close the blowing according to changes in the flight environment.

[0016] Furthermore, shutting down the micro-blowing unit requires closing the control valve to cut off the air supply, and the micro-blowing unit enters a non-blowing working state.

[0017] Furthermore, in order to reduce the friction resistance of the laminar boundary layer and the turbulent boundary layer, under the laminar state, the circular hole layer on the micro-blowing surface acts as a porous surface structure, which suppresses the unstable disturbance waves in the boundary layer through the acoustic feedback mechanism to achieve the drag reduction effect; under the turbulent state, the micro-blowing unit provides a small airflow, and the seeping airflow forms an isolation layer between the bottom of the turbulent boundary layer and the wall, suppressing the development of turbulence, thereby achieving turbulent drag reduction.

[0018] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. By installing a boundary layer laminar / turbulent flow state detector on the surface of the aircraft to control the excitation timing of the micro-blowing unit, the actual flow state on the aircraft surface, i.e. laminar or turbulent state, is judged according to a single pressure pulsation sensor, the working mode of the micro-blowing unit is intelligently and dynamically adjusted, and the working mode of the friction controller is started in a targeted manner to ensure that the control is always in the best working state, thereby achieving the purpose of maximizing the reduction of friction; 2. By setting up a multi-hole and micro-blowing combined device, the instability of the laminar boundary layer is suppressed by the multi-holes in the non-blowing mode, and the turbulent boundary layer flow structure is suppressed in the blowing mode, so that two control modes are realized with the same set of devices, and multiple devices are integrated into one device to save resources; and the device only starts blowing when the boundary layer is in a turbulent state, and does not start blowing in the laminar state, which can greatly save the consumption of the control air source, save precious mass load for the aircraft, and thus extend the working time of the controller. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the device of the present invention; Figure 2 It is a schematic diagram of the layout of the device of the present invention on the surface of an aircraft; Figure 3 The present invention is a flow chart of the method. DETAILED DESCRIPTION

[0020] The present invention will be described in detail below in conjunction with the accompanying drawings.

[0021] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0022] like Figure 1 and Figure 2 As shown, a laminar flow / turbulent flow friction integrated control device based on a micro-blowing surface, the control device specifically includes a micro-blowing surface, a high-frequency pressure pulsation sensor, a high-pressure gas storage tank, a control chip and a control valve; The micro-blowing surface is a control excitation unit of the control device, and the micro-blowing surface is connected to the control chip and the control valve respectively; Among them, the micro-blowing surface is set as a sandwich composite structure, and the sandwich composite structure is divided into three layers: upper, middle and lower; The upper layer is a layer of evenly distributed circular holes; The middle layer is a buffer layer, which is composed of low-permeability materials and is used to adjust the seepage rate; The lower layer is the air chamber, which is connected to the high-pressure gas storage tank through a control valve. The high-pressure gas source in the high-pressure gas storage tank enters the micro-blowing surface through the air chamber, and the high-pressure gas source forms a stable air layer at the bottom of the air chamber.

[0023] The high-frequency pressure pulsation sensor is a pressure pulsation detection sensor, and the high-frequency pressure pulsation sensor is arranged inside the micro-blowing surface. The high-frequency pressure pulsation sensor is used to transmit the monitored pressure pulsation timing signal to the control chip in real time for boundary layer laminar flow / turbulent flow state analysis; Among them, the high-frequency pressure pulsation sensor can judge the boundary layer flow state based on the following two methods: (1) Based on the pressure pulsation frequency, the laminar boundary layer is a flow dominated by discrete modes, and its spectrum usually has only a few discrete peaks; while the turbulent boundary layer has a broadband characteristic due to its strong nonlinearity. Based on this, the control chip only needs to perform a fast Fourier transform (FFT, as shown below) on the real-time pressure pulsation time series signal collected by the high-frequency pressure pulsation sensor to obtain the pressure pulsation spectrum, and then the laminar / turbulent state of the boundary layer can be identified. The pressure pulsation frequency formula is:

[0024] in, is the spectrum function of pressure pulsation, is the pressure pulsation timing signal, that is, the difference between the actual pressure signal and the average pressure. is the angular frequency, satisfying , is the frequency, is the time variable, is the kernel function of Fourier transform, which means projecting the signal onto different frequency components.

[0025] (2) Based on the pressure pulsation amplitude, in the laminar boundary layer, since the disturbance is in the early stage of growth, its amplitude is small relative to the boundary layer flow, while in the late transition and turbulent boundary layer, since the disturbance has grown to saturation and has strong nonlinear effects, the disturbance amplitude is of the same order of magnitude relative to the boundary layer flow and cannot be ignored. Therefore, the root mean square (RMS, as shown below) of the real-time pressure signal can be calculated, and a threshold can be set. If it is higher than this threshold, it can be considered that turbulence occurs; otherwise, it is laminar flow; the formula for the pressure pulsation amplitude is:

[0026] in, is the root mean square value of the pressure pulsation amplitude, is the starting time of integration, is the end time of integration, is the pressure pulsation signal, , is the average pressure.

[0027] Combining the two parameters of frequency and amplitude, using Fourier transform and root mean square (RMS) method to judge the boundary layer flow state is a method widely used in the prior art.

[0028] The high-pressure gas storage tank is connected to the micro-blowing surface through a control valve, and the high-pressure gas storage tank is used to provide a high-pressure gas source for the micro-blowing surface; Among them, the high-pressure gas storage tank is the largest mass load of this device. Its mass needs to be reduced as much as possible in the design to achieve the purpose of maximizing the reduction of friction resistance.

[0029] The control chip is connected to the high-frequency pressure pulsation sensor, and the boundary layer flow state is judged by reading the high-frequency pressure pulsation signal measured in real time by the high-frequency pressure pulsation sensor, and the opening and closing command signal is transmitted to the control valve according to the judgment result; The control valve is connected with the micro-blowing surface, the control chip and the high-pressure gas storage tank, and the high-pressure gas source of the high-pressure gas storage tank is controlled by opening and closing the control valve.

[0030] like Figure 3 As shown, a laminar / turbulent friction integrated control method based on a micro-blowing surface, the control method comprises: Start the device and provide gas source through the high-pressure gas tank; initialize the system to ensure that all components of the device can work normally; Pressure signal acquisition and flow state analysis: The high-frequency pressure pulsation sensor monitors the pressure pulsation signal on the aircraft surface in real time. The signal is transmitted to the control chip in a time sequence. The control chip determines the flow state of the boundary layer by analyzing the received pressure pulsation signal. Among them, the control chip determines the boundary layer flow state according to the received pressure pulsation signal, which is specifically: laminar state: if the signal indicates that the boundary layer is in a laminar state, the pressure pulsation signal is stable and has no violent fluctuations, and there are no or only a limited number of isolated dominant frequency signals in the frequency domain; turbulent state: if the signal indicates that the boundary layer is in a turbulent state, the pressure pulsation signal has strong irregular pulsations, and there are a series of continuous frequency signals in the frequency domain, which conforms to the law of turbulent energy spectrum.

[0031] Judge the flow state and control decision, and make a decision on whether to start micro-blowing based on the analysis results of the control chip; In the laminar flow state: the control chip sends a closing command to the control valve, the micro-blowing unit turns off the blowing, and the circular hole layer on the micro-blowing surface does not generate airflow; in the laminar flow state, the circular hole layer on the micro-blowing surface acts as a porous surface structure, suppressing unstable disturbance waves in the boundary layer through the acoustic feedback mechanism, thereby achieving a drag reduction effect; In the turbulent state, the control chip sends an opening command to the control valve, the control valve opens, the micro-blowing unit starts blowing, and the high-pressure air source flows into the air chamber through the control valve, and forms a tiny airflow through the buffer layer and the circular hole layer, which seeps out perpendicular to the surface of the aircraft. In the turbulent state, the micro-blowing unit provides a small airflow, and the seeping airflow forms an isolation layer between the bottom of the turbulent boundary layer and the wall, inhibiting the development of turbulence, thereby achieving turbulent drag reduction.

[0032] Continuous monitoring and adjustment: the system continuously monitors the state changes of the boundary layer through high-frequency pressure pulsation sensors; Among them, the control chip processes the pressure pulsation signal in real time, dynamically determines the state of the aircraft surface, and adjusts the working state of the micro-blowing unit according to the state of the aircraft surface; The micro-blowing unit switches its working state to open or close the blowing according to the changes in the flight environment.

[0033] According to the real laminar / turbulent state of the aircraft surface during actual flight, two working modes, with and without blowing, are realized: when the boundary layer is laminar, the micro-blowing unit does not blow air, and the circular hole layer on the micro-blowing surface constitutes a porous surface structure, which can suppress the unstable disturbance waves in the laminar boundary layer based on the acoustic feedback mechanism to achieve laminar drag reduction; when the boundary layer is turbulent, the micro-blowing unit performs micro-blowing, and the circular hole layer has a small speed airflow perpendicular to the wall, forming an isolation between the bottom of the turbulent boundary layer and the wall, thereby achieving turbulent drag reduction.

[0034] When the flight mission ends or the system enters standby mode, the micro-blowing unit is turned off to stop the airflow.

[0035] To shut down the micro-blowing unit, you need to close the control valve and cut off the air supply. The micro-blowing unit will enter sleep mode and will be reactivated the next time the aircraft flies.

[0036] Example like Figure 2 As shown, taking a conical shape aircraft as an example, Figure 2 The schematic diagram of the installation of the laminar / turbulent boundary layer friction integrated control device on the conical surface. Since the transition of the surface of a real aircraft (especially a complex three-dimensional configuration) occurs in partitions, in order to improve the control efficiency and accuracy, the micro-blowing surface is installed in a distributed manner to improve the flexibility of friction control. A high-frequency pressure pulsation sensor is installed in the middle of each micro-blowing surface area to monitor whether the flow in the micro-blowing surface arrangement area is in a laminar or turbulent state. In this way, a micro-blowing surface and a high-frequency pressure pulsation sensor constitute a basic control unit, in which the high-frequency pressure pulsation sensor is a signal detection input, and the micro-blowing surface is a control excitation output. Multiple control units can share a control chip and be equipped with a multi-way control valve to realize the coordinated control of the micro-blowing surfaces arranged in multiple different areas.

[0037] By dividing the micro-blowing surface into areas, the efficiency and accuracy of device control are improved.

[0038] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A laminar / turbulent friction integrated control device based on a micro-blowing surface, characterized in that: The control device has multiple components that work together to intelligently adjust the opening and closing of the micro-blowing unit under laminar or turbulent conditions. The control device specifically includes a micro-blowing surface, a high-frequency pressure pulsation sensor, a high-pressure gas storage tank, a control chip, and a control valve. The micro-blowing surface is a control excitation unit of the control device, and the micro-blowing surface is connected to the control chip and the control valve respectively; A high-frequency pressure pulsation sensor is arranged inside the micro-blowing surface. The high-frequency pressure pulsation sensor is used to transmit the monitored pressure pulsation timing signal to the control chip in real time for boundary layer laminar flow / turbulent flow state analysis; The high-pressure gas storage tank is connected to the micro-blowing surface through a control valve, and the high-pressure gas storage tank is used to provide a high-pressure gas source for the micro-blowing surface; The control chip is connected to the high-frequency pressure pulsation sensor, and the boundary layer flow state is judged by reading the pressure pulsation signal measured in real time by the high-frequency pressure pulsation sensor, and the opening and closing command signal is transmitted to the control valve according to the judgment result; The control valve is connected with the micro-blowing surface, the control chip and the high-pressure gas storage tank, and the high-pressure gas source of the high-pressure gas storage tank is controlled by opening and closing the control valve.

2. The laminar / turbulent friction integrated control device based on micro-blowing surface according to claim 1 is characterized in that: The micro-blowing surface is configured as a sandwich composite structure, and the sandwich composite structure is divided into three layers: upper, middle and lower; The upper layer is a layer of evenly distributed circular holes; The middle layer is a buffer layer, which is composed of low-permeability materials and is used to adjust the seepage rate; The lower layer is the air chamber, which is connected to the high-pressure gas storage tank through a control valve. The high-pressure gas source in the high-pressure gas storage tank enters the micro-blowing surface through the air chamber, and the high-pressure gas source forms a stable air layer at the bottom of the air chamber.

3. The laminar / turbulent friction integrated control device based on micro-blowing surface according to claim 1 is characterized in that: The micro-blowing surface is divided into areas, and each micro-blowing surface is provided with a high-frequency pressure pulsation sensor. The area of ​​each micro-blowing surface and the high-frequency pressure pulsation sensor in its area constitute a basic control unit. According to the division of the micro-blowing surface area, multiple basic control units are provided, and multiple basic control units share a control chip.

4. The laminar / turbulent friction integrated control device based on micro-blowing surface according to claim 3 is characterized in that: In the basic control unit, a high-frequency pressure pulsation sensor is used as a signal detection input, and a micro-blowing surface is used as a control excitation output.

5. A laminar flow / turbulent flow friction integrated control method based on a micro-blowing surface, using a laminar flow / turbulent flow friction integrated control device based on a micro-blowing surface according to any one of claims 1 to 4, characterized in that: The control method comprises: Start the device and provide gas source through the high-pressure gas tank; initialize the system to ensure that all components of the device can work normally; Pressure signal acquisition and flow state analysis: The high-frequency pressure pulsation sensor monitors the pressure pulsation signal on the aircraft surface in real time. The signal is transmitted to the control chip in a time sequence. The control chip determines the flow state of the boundary layer by analyzing the received pressure pulsation signal. Judge the flow state and control decision, and make a decision on whether to start micro-blowing based on the analysis results of the control chip; Continuous monitoring and adjustment: the system continuously monitors the state changes of the boundary layer through high-frequency pressure pulsation sensors; When the flight mission ends or the system enters standby mode, the micro-blowing unit is turned off to stop the airflow.

6. The laminar / turbulent friction integrated control method based on micro-blowing surface according to claim 5 is characterized in that: The control chip determines the boundary layer flow state according to the received pressure pulsation signal, which is specifically: Laminar flow state: If the signal indicates that the boundary layer is in a laminar flow state, the pressure pulsation signal is stable without violent fluctuations, and there are no or only a limited number of isolated dominant frequency signals in the frequency domain; Turbulent state: If the signal indicates that the boundary layer is in a turbulent state, the pressure pulsation signal has strong irregular pulsations, and there is a series of continuous frequency signals in the frequency domain, which conforms to the law of turbulent energy spectrum.

7. The laminar / turbulent friction integrated control method based on micro-blowing surface according to claim 5 is characterized in that: The flow state determination and control decision making specifically include the following steps: In the laminar flow state: the control chip sends a closing command to the control valve, the micro-blowing unit turns off the blowing, and the circular hole layer on the micro-blowing surface does not generate airflow; Under turbulent state: the control chip sends an opening command to the control valve, the control valve opens, the micro-blowing unit starts blowing, the high-pressure air source flows into the air chamber through the control valve, and forms a tiny airflow through the buffer layer and the circular hole layer, seeping out perpendicular to the surface of the aircraft.

8. The laminar / turbulent friction integrated control method based on micro-blowing surface according to claim 5, characterized in that: The continuous monitoring and adjustment includes the following steps: The control chip processes the pressure pulsation signal in real time, dynamically determines the state of the aircraft surface, and adjusts the working state of the micro-blowing unit according to the state of the aircraft surface; The micro-blowing unit switches its working state to open or close the blowing according to the changes in the flight environment.

9. The laminar / turbulent friction integrated control method based on micro-blowing surface according to claim 5, characterized in that: The closing of the micro-blowing unit requires closing the control valve to cut off the air supply, and the micro-blowing unit enters a non-blowing working state.

10. The laminar / turbulent friction integrated control method based on micro-blowing surface according to claim 7, characterized in that: Under laminar flow conditions, the circular hole layer on the micro-blowing surface acts as a porous surface structure, which suppresses unstable disturbance waves in the boundary layer through the acoustic feedback mechanism; under turbulent flow conditions, the micro-blowing unit provides a small airflow, and the seepage airflow forms an isolation layer between the bottom of the turbulent boundary layer and the wall, suppressing the development of turbulence.

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