Intelligent plasma flow control device and method for incident shock wave boundary layer interference

Abstract

The present application provides an intelligent plasma flow control device and method for incident shock wave boundary layer interference, relating to the field of flow control technology. The device includes a controller, a high-voltage pulse power supply, a flat plate, a plasma synthetic jet actuator, a first wall-surface hot wire module, a second wall-surface hot wire module, a shock generator, a grating, and a bracket. The plasma synthetic jet actuator, the first wall-surface hot wire module, and the second wall-surface hot wire module are sequentially installed on the flat plate in an upstream-to-downstream direction. The grating is installed perpendicularly on the bracket. The shock generator is connected to the bracket. A first inclination structure is provided at the upstream end of the shock generator, and the shock generator is located above the first wall-surface hot wire module and the second wall-surface hot wire module. The actuator is electrically connected to the high-voltage pulse power supply, and the controller is electrically connected to the high-voltage pulse power supply, the first wall-surface hot wire module, and the second wall-surface hot wire module, respectively. The present application has the advantages of greater robustness and adaptability.

Description

Technical Field

[0001] The present application relates to the field of flow control technology, and in particular to an intelligent plasma flow control device and method for incident shock wave boundary layer interference. Background Art

[0002] Shock wave / boundary layer interference is an unfavorable phenomenon in supersonic flight, widely present on aircraft surfaces and within air intake systems. When flight speeds exceed Mach 1, the incoming airflow inevitably encounters irregularities such as corners and wedges on the aircraft's fuselage. Unable to smoothly pass through these areas, the forward airflow is obstructed, while the rearward airflow maintains a constant velocity, causing compression of the gas within this area and forming multiple compression waves. Induced by pressure gradients, these multiple compression waves combine into one, known as a shock wave. Shock waves cause significant changes in air pressure, often strongly interfering with other flow field structures and profoundly impacting the supersonic flow field.

[0003] On the one hand, the strong adverse pressure gradient induced by the shock wave will cause boundary layer flow separation, resulting in a decrease in the total pressure recovery coefficient and flow coefficient of the inlet system; on the other hand, the low-frequency oscillation caused by the interference between the shock wave and the boundary layer will cause additional pulsating pressure loads on the aircraft structure, causing resonance and fatigue.

[0004] Currently, the main methods for suppressing shock wave / boundary layer interference include vortex generators, bulge deformation, wall suction, and plasma excitation. Both vortex generators and bulge deformation are passive flow control methods. Their basic principle is to induce streamwise vortices to promote mixing within the boundary layer, thereby improving the boundary layer's ability to resist adverse pressure gradients and achieving the purpose of reducing flow separation caused by shock waves. While these two passive control methods are effective, they can cause additional drag when there is no shock wave / boundary layer interference. Wall suction, as an active flow control method, can be freely turned on and off according to flight conditions, offering greater adaptability and no additional drag. However, to achieve air suction, components such as air ducts, suction pumps, and valves must be arranged within the aircraft, increasing the aircraft's structural weight coefficient.

[0005] Plasma aerodynamics is a novel active flow control method that exerts controllable disturbances on the flow field through the directional motion and heat release of plasma under the influence of an electromagnetic field. It boasts a simple structure, fast response, and high frequency response. However, existing plasma aerodynamics systems generally operate in an open-loop mode, requiring extensive debugging to select the optimal excitation voltage and frequency, which is time-consuming and laborious. Furthermore, due to open-loop control, the excitation voltage and frequency cannot be adaptively adjusted if the flight state changes, resulting in poor robustness and adaptability. Summary of the Invention

[0006] The purpose of the present application is to provide an intelligent plasma flow control device and method for incident shock wave boundary layer interference, so as to solve the problems of poor robustness and insufficient adaptability of plasma aerodynamic excitation in the prior art.

[0007] In order to achieve the above objectives, the technical solutions adopted in the embodiments of the present application are as follows:

[0008] On the one hand, an embodiment of the present application provides an intelligent plasma flow control device for incident shock wave boundary layer interference, the device comprising a controller, a high-voltage pulse power supply, a flat plate, a plasma synthetic jet actuator, a first wall hot wire module, a second wall hot wire module, a shock generator, a grating, and a bracket, the bracket being connected to the flat plate, the plasma synthetic jet actuator, the first wall hot wire module, and the second wall hot wire module being installed on the flat plate in sequence from upstream to downstream, the grating being installed vertically on the bracket, the shock generator being connected to the bracket, the upstream end of the shock generator being provided with a first inclination structure, and the shock generator being located above the first wall hot wire module and the second wall hot wire module;

[0009] The plasma synthetic jet actuator is electrically connected to the high-voltage pulse power supply, and the controller is electrically connected to the high-voltage pulse power supply, the first wall heat wire module and the second wall heat wire module respectively; wherein,

[0010] When in a supersonic flight environment, the airflow flows from upstream to downstream, and the shock wave generator is used to generate an incident oblique shock wave, and hit the area between the first wall heat line module and the second wall heat line module;

[0011] The plasma synthetic jet actuator is used to form a jet circulation to suppress shock wave boundary layer interference;

[0012] The first wall heat line module and the second wall heat line module are used to obtain the air status at corresponding positions;

[0013] The controller is used to adjust the supply voltage and / or supply frequency of the high-voltage pulse power supply according to the air state, so as to adjust the discharge voltage and / or discharge frequency of the plasma synthetic jet actuator.

[0014] Optionally, the upstream end of the flat plate is provided with a second inclination structure, the downstream end of the shock wave generator is provided with a third inclination structure, and the inclination angle of the second inclination structure is the same as that of the third inclination structure.

[0015] Optionally, the inclination angle of the first inclination structure is 5°~20°.

[0016] Optionally, a long strip-shaped mounting groove is provided on the side of the shock wave generator, the length of the mounting groove is greater than the length of the cradle, and the cradle is installed at any position of the mounting groove and fixed by a fixing member.

[0017] Optionally, the plasma synthetic jet actuator includes a cathode, an anode, an isolation boss and a main body, the main body is provided with a jet cavity, each cathode and an anode form an electrode pair arranged in the jet cavity, and the isolation boss is located between the cathode and anode of each motor pair, and the cathode and anode of each electrode pair are connected to the high-voltage pulse power supply.

[0018] Optionally, the distance between two adjacent electrode pairs is set to 3-5 mm.

[0019] Optionally, the first wall hot wire module and the second wall hot wire module have the same structure, and the first wall hot wire module includes a hot wire probe, a top screw, a fastening screw and a base, the base is arranged in an inverted T-shaped structure, and a mounting hole is provided on the top of the base, the hot wire probe is installed in the mounting hole and fixed by the top screw; mounting holes are provided on both sides of the base, the fastening screws are located in the mounting holes, and the base is fixed to the flat plate.

[0020] Optionally, the plasma synthetic jet actuator, the first wall hot line module, and the second wall hot line module are all installed at the bottom of the flat plate, and the surfaces of the plasma synthetic jet actuator, the first wall hot line module, and the second wall hot line module are flush with the surface of the bracket.

[0021] On the other hand, an embodiment of the present application further provides an intelligent plasma flow control method for incident shock wave boundary layer interference, which is applied to the above-mentioned intelligent plasma flow control device for incident shock wave boundary layer interference, and the method includes:

[0022] controlling the supply voltage and / or supply frequency of the high-voltage pulse power supply to operate the plasma synthetic jet actuator;

[0023] Acquiring the state of air transmitted by the first wall heat line module and the second wall heat line module;

[0024] The supply voltage and / or supply frequency of the high-voltage pulse power supply is adjusted based on the reinforcement learning model and the air state until the shock wave boundary layer interference is completely suppressed.

[0025] Optionally, the step of adjusting the supply voltage and / or supply frequency of the high-voltage pulse power supply based on the reinforcement learning model and the air state includes:

[0026] determining the size of the flow separation zone according to the state of air transmitted by the first wall heat line module and the second wall heat line module;

[0027] determining whether a difference between a flow separation zone size in a current cycle and a flow separation zone size in a previous cycle is positive, and if so, increasing a reward of the reinforcement learning model;

[0028] Based on the reinforcement learning model combined with the adjusted reward and the air state, the supply voltage and / or supply frequency of the next cycle of the high-voltage pulse power supply is generated.

[0029] Compared with the prior art, this application has the following beneficial effects:

[0030] The present application provides an intelligent plasma flow control device and method for incident shock wave boundary layer interference, the device includes a controller, a high-voltage pulse power supply, a flat plate, a plasma synthetic jet exciter, a first wall hot wire module, a second wall hot wire module, a shock wave generator, a grating and a bracket, the bracket is connected to the flat plate, the plasma synthetic jet exciter, the first wall hot wire module, and the second wall hot wire module are installed on the flat plate in sequence from upstream to downstream, the grating is vertically installed on the bracket, the shock wave generator is connected to the bracket, the upstream end of the shock wave generator is provided with a first inclination structure, and the shock wave generator is located above the first wall hot wire module and the second wall hot wire module; the plasma synthetic jet exciter It is electrically connected to the high-voltage pulse power supply, and the controller is electrically connected to the high-voltage pulse power supply, the first wall hot wire module and the second wall hot wire module respectively; wherein, when in a supersonic flight environment, the airflow flows from upstream to downstream, and the shock wave generator is used to generate an incident oblique shock wave and hit the area between the first wall hot wire module and the second wall hot wire module; the plasma synthetic jet actuator is used to form a jet circulation to suppress shock wave boundary layer interference; the first wall hot wire module and the second wall hot wire module are used to obtain the air state at corresponding positions; the controller is used to adjust the power supply voltage and / or power supply frequency of the high-voltage pulse power supply according to the air state, so as to adjust the discharge voltage and / or discharge frequency of the plasma synthetic jet actuator.

[0031] The new intelligent plasma flow control device for incident shock wave boundary layer interference provided in this application can measure the air state through the first wall hot wire module and the second wall hot wire module. At the same time, the controller can adjust the discharge voltage and / or discharge frequency of the plasma synthetic jet actuator in real time according to the air state, so that when the flight state changes, the excitation voltage and frequency can be adaptively adjusted, thereby improving the robustness of the entire device.

[0032] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0034] Figure 1 This is a schematic structural diagram of the intelligent plasma flow control device for incident shock wave boundary layer interference provided in this application.

[0035] Figure 2 Bottom view of the intelligent plasma flow control device for incident shock wave boundary layer interference provided by this application.

[0036] Figure 3 This is a top view of the intelligent plasma flow control device for incident shock wave boundary layer interference provided by the present application after removing the flat plate.

[0037] Figure 4 This is a module schematic diagram of the intelligent plasma flow control device for incident shock wave boundary layer interference provided in this application.

[0038] Figure 5 This is a schematic structural diagram of the plasma synthetic jet actuator provided in this application.

[0039] Figure 6 for Figure 5 Schematic diagram of the cross section of the structure along lines AA and BB.

[0040] Figure 7 This is a structural schematic diagram of the first wall heating wire module provided in this application.

[0041] Figure 8 for Figure 7 Schematic diagram of the cross section of the structure along line AA.

[0042] Figure 9 for Figure 7 Schematic diagram of the cross section of the middle structure along line BB.

[0043] Figure 10 This is an exemplary flow chart of the intelligent plasma flow control method for incident shock wave boundary layer interference provided in this application.

[0044] Figure 11 This is a schematic diagram of the processing logic of the intelligent plasma flow control method for incident shock wave boundary layer interference provided in this application.

[0045] In the picture:

[0046] 100-flat plate; 110-second inclination structure; 120-plasma synthetic jet hole; 200-plasma synthetic jet actuator; 201-anode; 202-cathode; 203-isolation boss; 204-jet cavity; 205-potting cavity; 310-first wall hot wire module; 320-second wall hot wire module; 301-hot wire probe; 302-top screw; 303-fastening screw; 304-base; 400-shock wave generator; 410-first inclination structure; 420-mounting slot; 430-third inclination structure; 510-left lattice frame; 520-right lattice frame; 600-bracket; 610-base plate; 620-cylindrical tail support rod; 630-top screw hole; 640-connection structure; 700-controller; 800-high-voltage pulse power supply. DETAILED DESCRIPTION

[0047] To make the objectives, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Generally, the components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0048] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for protection, but merely represents selected embodiments of the present application. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments in the present application without creative work are within the scope of protection of the present application.

[0049] It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and should not be understood as indicating or implying relative importance.

[0050] It should be noted that, in this document, relational terms such as first and second, etc. are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations.

[0051] As described in the background art, current plasma aerodynamic excitation generally adopts open-loop control, and the optimal excitation voltage and frequency cannot be adaptively adjusted, resulting in poor robustness.

[0052] In view of this, the present application provides an intelligent plasma flow control device for incident shock wave boundary layer interference, which adaptively adjusts the discharge voltage and / or discharge frequency of the plasma synthetic jet actuator 200 through a new structure and controller to achieve the purpose of improving the robustness of the entire device.

[0053] The following is an exemplary description of the intelligent plasma flow control device for incident shock wave boundary layer interference provided by the present application:

[0054] As an optional implementation, see Figure 1-Figure 4 The device includes a controller 700, a high-voltage pulse power supply 800, a flat plate 100, a plasma synthetic jet actuator 200, a first wall hot wire module 310, a second wall hot wire module 320, a shock wave generator 400, a grating and a bracket 600. The bracket 600 is connected to the flat plate 100. The plasma synthetic jet actuator 200, the first wall hot wire module 310, and the second wall hot wire module 320 are installed on the flat plate 100 in sequence from upstream to downstream. The grating is vertical. It is installed on the bracket 600, the shock wave generator 400 is connected to the bracket 600, a first inclined structure 410 is set at the upstream end of the shock wave generator 400, and the shock wave generator 400 is located above the first wall hot wire module 310 and the second wall hot wire module 320; the plasma synthetic jet exciter 200 is electrically connected to the high-voltage pulse power supply 800, and the controller 700 is electrically connected to the high-voltage pulse power supply 800, the first wall hot wire module 310 and the second wall hot wire module 320 respectively. Among them, when in a supersonic flight environment, the airflow flows from upstream to downstream, and the shock wave generator 400 is used to generate an incident oblique shock wave and hit the area between the first wall hot wire module 310 and the second wall hot wire module 320; the plasma synthetic jet actuator 200 is used to form a jet circulation to suppress shock wave boundary layer interference; the first wall hot wire module 310 and the second wall hot wire module 320 are used to obtain the air state at the corresponding position; the controller 700 is used to adjust the supply voltage and / or supply frequency of the high-voltage pulse power supply 800 according to the air state to adjust the discharge voltage and / or discharge frequency of the plasma synthetic jet actuator 200.

[0055] The intelligent plasma flow control device for incident shock wave boundary layer interference provided herein enables the controller 700 to flexibly adjust the discharge voltage and / or discharge frequency of the plasma synthetic jet actuator 200 based on the air conditions detected by the first wall hot wire module 310 and the second wall hot wire module 320, until the incident shock wave boundary layer interference is completely suppressed. In other words, the controller 700 can implement closed-loop control, improving the robustness of the entire device.

[0056] The upstream and downstream mentioned in this application are directions defined for the direction of airflow. When in flight, the airflow flows from upstream to downstream. Figure 1 Shown in the middle perspective, the left side of the figure is upstream and the right side is downstream.

[0057] In addition, the flat plate 100 described in the present application is mainly used to install the structure of the plasma synthetic jet actuator 200, the first wall hot wire module 310, and the second wall hot wire module 320. Since the plasma synthetic jet actuator 200 is driven by high-voltage pulses when in operation, in order to prevent creepage with the actuator under high-voltage conditions, the material of the flat plate 100 is preferably a high-strength non-metallic material Peek (polyetheretherketone).

[0058] At the same time, to reduce wind resistance across the entire device, a second angled structure 110 is provided at the upstream end of the flat plate 100. The angled structure described herein refers to a situation where both the top and bottom surfaces of the flat plate 100 are flat, with the bottom surface of the flat plate 100 being shorter than the top surface. This creates an inclined surface on the side of the upstream end of the flat plate 100. This inclined surface forms an acute angle with the surface of the flat plate 100 and an obtuse angle with the bottom surface of the flat plate 100, thereby forming a downward-sloping wedge structure (angled structure) across the entire upstream end. To enhance wind resistance reduction, the angle of inclination of the upstream end of the flat plate 100 is set between 10° and 20°.

[0059] Furthermore, the bottom of the flat panel 100 is connected to the bracket 600, which primarily serves as a support. To further reduce wind resistance, the bottom of the flat panel 100 is configured as a stepped structure, meaning that the upstream end of the flat panel 100 is lower than the rest of the bottom surface of the flat panel 100, creating a height difference. The thickness of the bracket 600 at the connection between the flat panel 100 and the bracket 600 is equal to this height difference, so that after the bottom of the flat panel 100 is secured to the bracket 600, the bottom surface of the bracket 600 is flush with the bottom surface of the upstream end of the flat panel 100. Therefore, the connection between the flat panel 100 and the bracket 600 is located on the bottom surface of the flat panel 100, and the bottom surfaces between the two are flush, effectively preventing surface clutter from affecting the flow field.

[0060] In order to ensure the firmness of the fixation between the tablet 100 and the bracket 600, Figure 2 As shown, the tablet 100 is connected to the bracket 600 via a bottom connection structure 640. In this application, the connection structure 640 includes four groups of eight screws. Since the plasma synthetic jet actuator 200, the first wall heat line module 310, and the second wall heat line module 320 are mounted in the middle of the bottom surface of the tablet 100, eight screws are sufficient to secure the tablet 100 to both sides, four screws per side, to achieve a stable connection between the tablet 100 and the bracket 600.

[0061] In order to facilitate the installation of the plasma synthetic jet actuator 200, the first wall hot line module 310, and the second wall hot line module 320, corresponding installation slots are reserved on the flat panel 100. Of course, in order to match the installation slots, a hollow structure is also adopted at the corresponding position of the bracket 600.

[0062] A row of plasma synthetic jet holes 120 is reserved in the center of the plate 100, corresponding to the plasma synthetic jet actuator 200. The aperture diameter can range from 1 to 3 mm, with a preferred aperture of 3 mm to maximize jet mass flow. The spanwise spacing (i.e., the width of the plate 100) between two adjacent holes should be 5 to 10 times the hole diameter. The number of plasma synthetic jet holes 120 is determined by the spanwise dimensions of the plate 100 and the spanwise spacing between the holes, as shown in Figure 1. Figure 3 The flat plate 100 provided herein has a span dimension of 100 mm, corresponding to five plasma synthetic jet orifices 120. Downstream of the orifices, two sets of mounting slots are reserved for mounting the first wall heating module 310 and the second wall heating module 320. Screws securely fasten the first and second wall heating modules 310, 320, and the flat plate 100.

[0063] As an implementation, see Figure 5-Figure 6 , Figure 6 a in the middle is Figure 5 The cross-sectional diagram of the structure along line AA. Figure 6 b in the middle Figure 5 Schematic cross-sectional view of the structure along line BB. The plasma synthetic jet actuator 200 is configured as a T-shaped, elongated structure that fits into a reserved slot in the flat plate 100, tightly fitting with the flat plate 100 to form a flat bottom surface. The primary function of the plasma synthetic jet actuator 200 is to generate a synthetic jet through high-voltage plasma discharge, thereby suppressing shock wave boundary layer interference. Because high temperatures are generated during plasma discharge, the actuator is preferably made of non-metallic, high-temperature-resistant ceramic materials such as alumina and zirconia.

[0064] The plasma synthetic jet actuator 200 mainly includes a cathode 202, an anode 201, an isolation boss 203 and a main body. The main body is provided with a jet cavity 204. Each cathode 202 and an anode 201 form an electrode pair and are arranged in the jet cavity 204. The isolation boss 203 is located between the cathode 202 and the anode 201 of each motor pair. The cathode 202 and the anode 201 of each electrode pair are connected to the high-voltage pulse power supply 800. Figure 5As shown, in the plasma synthetic jet actuator 200 provided by the present application, 5 pairs of positive and negative high-voltage electrodes are evenly distributed along the span direction in the jet cavity 204. Of course, the number of electrode pairs can be adjusted according to the actual size of the jet cavity 204. In addition, the electrode material of the anode 201 and the cathode 202 is selected to be a high-temperature resistant tungsten needle with a diameter of 1 mm. At the same time, the spacing between two adjacent electrode pairs is also determined by the lateral width of the jet cavity 204. In order to ensure that the breakdown voltage is between 10kV and 20kV, the spacing between two adjacent electrode pairs is set to 3-5mm, for example, it can be set to 4mm.

[0065] Among them, the isolation boss 203 is used to prevent the ablation of the cavity material. Specifically, during the operation of the exciter, the anode 201 and the cathode 202 are respectively connected to the high-voltage pulse power supply 800 through high-voltage resistant wires. Ideally, the tips of the anode 201 and the cathode 202 will form a discharge arc to heat the gas inside the jet cavity 204. However, in the actual operation process, the roots of the anode 201 and the cathode 202 will form a surface discharge on the bottom surface of the cavity, causing ablation of the cavity material. Therefore, in order to avoid this situation, the exciter provided in the present application is provided with an isolation boss 203, which increases the total length of the discharge path along the bottom surface, thereby effectively avoiding the ablation of the cavity material. Optionally, the width of the isolation boss 203 is 1 mm and the height is 2 mm.

[0066] In addition, to achieve electrode fixation and high-voltage insulation, a rectangular potting cavity 205 is provided at the bottom of the main body. After the tungsten needle electrode and the metal wire are connected, epoxy potting glue is injected into the potting cavity 205 to seal the potting cavity 205.

[0067] In this application, the basic operating principle of the plasma synthetic jet actuator 200 for jet generation is as follows: pulsed high voltage (ranging from 5kV to 30kV) is applied to the actuator's electrodes, causing the gas between the electrodes to break down and form a high-temperature plasma. A transient high pressure is generated within the jet cavity 204, forcing a high-temperature, high-pressure gas mass to be ejected at high speed from the plasma synthetic jet orifice 120. After the jet is ejected, the pressure differential between the cavity and the outside causes the external gas to be refilled through the orifice, thus forming a periodic synthetic jet cycle of "injection-intake-injection-intake." This synthetic jet can, on the one hand, inject momentum into the shock boundary layer interference region, enhancing the kinetic energy of the boundary layer fluid to resist the adverse pressure gradient. On the other hand, the periodic jet perturbs the local high-speed flow field structure, forming a streamwise vortex structure in the shock-induced separation region, effectively suppressing the formation of turbulent separation bubbles and enhancing the suppression of shock boundary layer interference.

[0068] The first wall heating module 310 and the second wall heating module 320 provided in this application are identical in structure. Figure 7-Figure 9 The first wall hot wire module 310 includes a hot wire probe 301, a top screw 302, a fastening screw 303 and a base 304. The base 304 is arranged in an inverted T-shaped structure. A mounting hole is provided on the top of the base 304. The hot wire probe 301 is installed in the mounting hole and fixed by the top screw 302; mounting holes are provided on both sides of the base 304. The fastening screws 303 are located in the mounting holes on both sides and fix the base 304 on the flat plate 100.

[0069] The substrate 304 is made of a high-temperature-resistant, high-strength non-metallic material, such as Peek or polyimide. Furthermore, the first wall hot wire module 310 provided herein includes three hot wire probes 301, which are used to measure the air velocity attached to the wall, thereby measuring the spanwise frictional resistance distribution of the flat plate 100's boundary layer. The hot wire probes 301 are cylindrical, with a diameter of 3 mm to 5 mm.

[0070] In this application, a ±0.05mm assembly tolerance is reserved between the hot-wire probe 301 and the base 304. Top screw holes are provided on the front and back sides of the base 304. Once the hot-wire probe 301 is installed in the mounting hole at the top of the base 304, the distance between the hot-wire probe 301 and the collective wall is only 0.2mm. The hot-wire probe 301 is secured with top screws 302. After the first wall-mounted hot-wire module 310 is mounted on the tablet 100, it can be secured using the mounting holes on both sides of the base 304 and the fastening screws 303.

[0071] It should be noted that although the first wall heating module 310 and the second wall heating module 320 have the same structure and are both used to measure air conditions (ie, air velocity), their locations and purposes of measuring air conditions are different.

[0072] Specifically, the first wall heat line module 310 is installed in the center of the flat plate 100, upstream of the shock boundary layer interference region (the shock boundary layer interference region is located between the first wall heat line module 310 and the second wall heat line module 320). Its function is to detect and determine whether flow separation has occurred at its location, providing status input for the subsequent intelligent control of the controller 700. The second wall heat line module 320 is installed downstream of the flat plate 100, corresponding to the downstream of the shock boundary layer interference region. Its function is to assess whether the plasma synthetic jet has completely eliminated flow separation in the downstream boundary layer. The combination of the first wall heat line module 310 and the second wall heat line module 320 can complete the evaluation of the extent of flow separation induced by shock boundary layer interference and the control effectiveness of the plasma actuator.

[0073] It should also be noted that after installation, the plasma synthetic jet actuator 200, the first wall heat line module 310, and the second wall heat line module 320 are all installed on the bottom of the flat plate 100, and the surfaces of the plasma synthetic jet actuator 200, the first wall heat line module 310, and the second wall heat line module 320 are flush with the surface of the bracket 600 to avoid the generation of clutter that affects the flow field. For example, please refer again Figure 2 and Figure 3 , Figure 2 In the embodiment, after the plasma synthetic jet actuator 200 , the first wall heating module 310 , and the second wall heating module 320 are installed, they are embedded in the structure of the flat plate 100 and the bracket 600 , and their surfaces are flush with the bottom surface of the bracket 600 . Figure 3 In the example, only the jet holes, the top surface of the base 304 of the first wall-mounted hot-wire module 310, and the second wall-mounted hot-wire module 320 are exposed on the surface of the flat plate 100. The mounting holes on the top surface of the base 304 are exposed, exposing the hot-wire probes 301. Furthermore, the exposed top surface of the base 304 is flush with the surface of the flat plate 100, thus preventing the generation of clutter.

[0074] The bracket 600 provided in this application includes a base plate 610 and a cylindrical tail support rod 620, both of which are made of high-strength metal materials to support the entire device. The base plate 610 is connected to the flat plate 100 via four groups of eight screws, and the middle portion is hollowed out to facilitate the assembly of the exciter, wall heating module, and flat plate 100. At the same time, the downstream end of the base plate 610 is provided with a mounting portion for fixing the lattice. The mounting portion forms a height difference with the rest of the base plate 610, which is equal to the thickness of the flat plate 100. After the bracket 600 and flat plate 100 are assembled, the mounting portion is flush with the surface of the flat plate 100.

[0075] The cylindrical tail support rod 620 provides an external interface and fixed end for the entire device. The circuit wiring of the plasma synthetic jet actuator 200, the first wall hotline module 310, and the second wall hotline module 320 can be led out through the hollow area of ​​the cylindrical tail support rod 620. At the same time, when the device is placed in a wind tunnel measurement system for testing, the cylindrical tail support rod 620 can be used to fix the entire device, thereby preventing it from shaking. The cylindrical tail support rod 620 has a diameter of 20mm and is provided with a screw hole 630. When using the cylindrical tail support rod 620 for fixing, the cylindrical tail support rod 620 and the external environment are fixed by two groups of four screws.

[0076] The lattice is mainly used to support the shock wave generator 400, and a high-strength metal material such as stainless steel can be selected. In the present application, the lattice includes a left lattice 510 and a right lattice 520, and the structures of the left lattice 510 and the right lattice 520 are exactly the same. The height of the two is 30 mm, and the upper and lower surfaces are respectively fixed to the shock wave generator 400 and the bracket 600 by 4 fastening screws, playing a vertical support role. Among them, the upstream and downstream ends of the left lattice 510 and the right lattice 520 are set to a wedge shape, thereby achieving the purpose of reducing wind resistance.

[0077] In the present application, a first angled structure 410 is provided at the upstream end of the shock generator 400. As an implementation, the angle of the first angled structure 410 is 5° to 20°, for example, 10 degrees, thereby generating an incident shock wave, which strikes the area between the first wall-surface hot wire module 310 and the second wall-surface hot wire module 320. The shock generator 400 can also be made of a high-strength metal material such as stainless steel.

[0078] In addition, a long strip-shaped mounting groove 420 is provided on the side of the shock wave generator 400. The length of the mounting groove 420 is set to 50-100 mm, and the length of the mounting groove 420 is greater than the length of the crochet, so that the crochet can be installed at any position of the mounting groove 420 and fixed by a fixing part. By providing the mounting groove 420 on the side of the shock wave generator 400, on the one hand, it is convenient to connect to the crochet through countersunk fastening screws. On the other hand, it can facilitate the shock wave generator 400 to move forward and backward along the direction of the flat plate 100. That is, during the test process, the position of the shock wave generator 400 can be manually adjusted, and then the position of the incident shock wave can be adjusted, so as to simulate different working conditions during the flight process.

[0079] At the same time, a third inclination structure 430 is provided at the downstream end of the shock wave generator 400, and the inclination angle of the upstream end of the flat plate 100 is the same as the inclination angle of the downstream end of the shock wave generator 400, generally set to 10°~20°, thereby effectively reducing the wind resistance as a whole.

[0080] It is understandable that the intelligent plasma flow control device for incident shock wave boundary layer interference provided by the present application can create an effective flow field environment for shock wave boundary layer interference in a wind tunnel measurement system. In this environment, the supply voltage and / or supply frequency of the high-voltage pulse power supply 800 can be adjusted by the controller 700, ultimately achieving complete suppression of shock wave boundary layer interference. At the same time, when creating a flow field environment for shock wave boundary layer interference, the first inclination structure 410 degrees of the upstream end of the shock wave generator 400 can be adjusted, as well as the installation position of the shock wave generator 400 and the gantry, so as to simulate different operating conditions during normal flight and enhance the flexibility of the simulation.

[0081] After the device is installed in the supersonic wind tunnel, when the wind tunnel is started, when the supersonic airflow flows over the surface of the flat plate 100, a boundary layer with a relatively low speed is formed under the action of viscosity; at the same time, the supersonic airflow is compressed by the wedge of the shock wave generator 400 (i.e., the first inclined structure 410 at the upstream end), generating an incident oblique shock wave with a deflection angle, which hits the area between the first wall hot line module 310 and the second wall hot line module 320 (i.e., the experimental observation area); under the action of the strong adverse pressure gradient of the shock wave, the kinetic energy in the boundary layer is rapidly dissipated and flow separation occurs, forming features such as unsteady separation bubbles, creating effective shock wave boundary layer interference.

[0082] After creating the flow field environment, the controller 700 can implement closed-loop control through the device's plasma synthetic jet actuator 200, first wall heat wire module 310, and second wall heat wire module 320. This adjusts the supply voltage and / or frequency of the high-voltage pulse power supply 800, thereby regulating the discharge voltage and / or frequency of the plasma synthetic jet actuator 200 to fully suppress shock wave boundary layer interference. The closed-loop control of the controller 700 can be implemented in conjunction with machine learning methods, which are not limited herein.

[0083] Based on the above implementation, the present invention also provides an intelligent plasma flow control method for incident shock wave boundary layer interference, which is applied to the controller in the above device. Figure 10 , methods include:

[0084] S102, controlling the supply voltage and / or supply frequency of the high-voltage pulse power supply to operate the plasma synthetic jet actuator.

[0085] S104: Acquire the state of air transmitted by the first wall heating module and the second wall heating module.

[0086] S106 , adjusting the supply voltage and / or supply frequency of the high-voltage pulse power supply based on the reinforcement learning model and the air state until the shock wave boundary layer interference is completely suppressed.

[0087] The step of S106 includes:

[0088] S1061: Determine the scale of the flow separation zone according to the state of air transmitted by the first wall heat line module and the second wall heat line module.

[0089] S1062: Determine whether the difference between the flow separation area scale of the current cycle and the flow separation area scale of the previous cycle is positive. If so, increase the reward of the reinforcement learning model.

[0090] S1063 , generating a supply voltage and / or supply frequency of the next cycle of the high-voltage pulse power supply based on the reinforcement learning model in combination with the adjusted reward and the air state.

[0091] Please combine Figure 11 After creating the shock wave flow field environment, sensing is performed via the first and second wall hotline modules 310, 320 located upstream and downstream, enabling state monitoring and generating a flow field state s. The corresponding flow field state s consists of two components: the boundary layer separation point measured by the first wall hotline module 310 and the boundary layer attachment point measured by the second wall hotline module 320. (Both the first and second wall hotline modules 310, 320 measure air velocity, but the meanings of their measurements differ.) Action a represents the supply voltage and discharge frequency of the plasma synthetic jet actuator 200, which can be adjusted using a high-voltage pulse power supply. The reward r is defined as the difference between the flow separation zone scale (the area between the first and second wall hotline modules 310, 320 affected by the shock wave boundary layer) in the current control cycle and the flow separation scale in the previous control cycle. A positive difference indicates that the separation zone has decreased after applying flow control in a given state, and therefore a higher reward should be given. The control law for active flow control is a functional mapping from state s to action a, which can be optimized using a reinforcement learning framework, for example, a neural network framework.

[0092] The specific process of control law optimization using reinforcement learning is as follows: the control law is randomly initialized; then, the current state s is monitored and a control command (i.e., action a) is output according to the preset control law. The control reward r is then evaluated, and experience samples (including the action a previously taken for state s and the reward r) are stored in an experience pool. The order of the experience samples is shuffled to make them independent and facilitate subsequent network updates. After a specified number of steps, the execution network is updated using PPO, actor-criticism, or other learning frameworks. Furthermore, to ensure stable network training, a target network is introduced whose update is delayed a certain number of steps from the execution network, ranging from 2 to 32. Alternatively, gradient descent can be used to update parameters using a loss function (such as the mean squared error function). Simultaneously, experience samples are randomly fed into the network from the experience pool. Finally, after multiple iterations, the instantaneous actuator input frequency is modified to control the actuator jet flow, thereby obtaining more rewards and achieving optimal shock wave separation suppression with minimal effort.

[0093] In summary, the present application solves the limitations of traditional fixed-position shock wave impact through a structural design in which the position of the incident shock wave can be adjusted along the flow direction, and flexibly adapts to the actual separation areas of different wind tunnel test models; uses two wall hot wire modules to obtain the flow field state in real time, and combines the reinforcement learning algorithm to autonomously optimize the excitation voltage and / or frequency of the plasma synthetic jet actuator 200 to achieve the best shock wave separation suppression effect, solving the problems of low efficiency of traditional manual parameter adjustment, high cost of wind tunnel testing, and difficulty in quantifying the control effect.

[0094] At the same time, the intelligent plasma flow control device for incident shock wave boundary layer interference provided by the present application has at least the following advantages:

[0095] 1. This application provides stronger plasma excitation: Traditional incident shock wave models based on synthetic jet actuators often use single-point or dual-point jet layouts, and their jet intensity and range are limited by local flow field characteristics. This application uses five jet ports arranged equidistantly along the span to actively control the flow in the incident shock wave separation region, improving the control effect in the shock wave separation region.

[0096] 2. More flexible control and position adjustment: The shock wave position in traditional incident shock wave wind tunnel test models is relatively fixed, making it difficult to accurately match the actual separation area under different wind tunnel test conditions. This invention achieves a dual design of on-demand angle adjustment and flexible flow-direction position adjustment in the incident shock wave generator structure. This achieves dynamic matching of the incident shock wave intensity with the model test area, improving the model's compatibility under different wind tunnel test conditions.

[0097] 3. High Optimization Efficiency: Traditional methods for active flow control involving incident shock waves suffer from low manual parameter adjustment efficiency, high wind tunnel testing costs, and difficulty quantifying control effects. This application utilizes a first and second wall hotline module to acquire flow field information in real time, combined with a reinforcement learning algorithm to autonomously optimize the excitation voltage and / or frequency of the plasma synthetic jet actuator, achieving optimal shock wave separation suppression. This method significantly reduces labor and testing costs, and by evaluating control effects through hotline data, it holds significant value in advancing the development of intelligent high-speed flow control.

[0098] 4. Strong Adaptability: In this application, the plasma synthetic jet actuator operates in a closed-loop state. As flight conditions change, the flow field information measured by the first and second wall-mounted hot-wire modules will change, causing adaptive adjustments to the actuator control instructions. Compared to conventional open-loop fixed-parameter control, this system offers greater adaptability and robustness.

[0099] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

[0100] It will be apparent to those skilled in the art that the present application is not limited to the details of the exemplary embodiments described above and that the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present application is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. An intelligent plasma flow control device for incident shock wave boundary layer interference, characterized in that: The device includes a controller, a high-voltage pulse power supply, a flat plate, a plasma synthetic jet actuator, a first wall hot wire module, a second wall hot wire module, a shock wave generator, a grating and a bracket, wherein the bracket is connected to the flat plate, the plasma synthetic jet actuator, the first wall hot wire module, and the second wall hot wire module are sequentially installed on the flat plate at intervals from upstream to downstream, the grating is vertically installed on the bracket, the shock wave generator is connected to the bracket, the upstream end of the shock wave generator is provided with a first inclination structure, and the shock wave generator is located above the first wall hot wire module and the second wall hot wire module; The plasma synthetic jet actuator is electrically connected to the high-voltage pulse power supply, and the controller is electrically connected to the high-voltage pulse power supply, the first wall heat wire module and the second wall heat wire module respectively; wherein, When in a supersonic flight environment, the airflow flows from upstream to downstream, and the shock wave generator is used to generate an incident oblique shock wave, and hit the area between the first wall heat line module and the second wall heat line module; The plasma synthetic jet actuator is used to form a jet circulation to suppress shock wave boundary layer interference; The first wall heat line module and the second wall heat line module are used to obtain the air status at corresponding positions; The controller is used to adjust the supply voltage and / or supply frequency of the high-voltage pulse power supply according to the air state, so as to adjust the discharge voltage and / or discharge frequency of the plasma synthetic jet actuator; The first wall hot wire module has the same structure as the second wall hot wire module, and the first wall hot wire module includes a hot wire probe, a top screw, a fastening screw and a base. The base is arranged in an inverted T-shaped structure, and a mounting hole is provided on the top of the base. The hot wire probe is installed in the mounting hole and fixed by the top screw; mounting holes are also provided on both sides of the base. The fastening screws are located in the mounting holes on both sides and fix the base to the flat plate.

2. The intelligent plasma flow control device for incident shock wave boundary layer interference according to claim 1, characterized in that: The upstream end of the flat plate is provided with a second inclination structure, the downstream end of the shock wave generator is provided with a third inclination structure, and the inclination degree of the second inclination structure is the same as that of the third inclination structure.

3. The intelligent plasma flow control device for incident shock wave boundary layer interference according to claim 1, characterized in that: The inclination angle of the first inclination structure is 5°~20°.

4. The intelligent plasma flow control device for incident shock wave boundary layer interference according to claim 1, characterized in that: A long strip-shaped mounting groove is provided on the side of the shock wave generator. The length of the mounting groove is greater than the length of the cradle. The cradle is installed at any position of the mounting groove and fixed by a fixing piece.

5. The intelligent plasma flow control device for incident shock wave boundary layer interference according to claim 1, characterized in that: The plasma synthetic jet actuator includes a cathode, an anode, an isolation boss and a main body. The main body is provided with a jet cavity. Each cathode and an anode form an electrode pair and are arranged in the jet cavity. The isolation boss is located between the cathode and anode of each motor pair. The cathode and anode of each electrode pair are connected to the high-voltage pulse power supply.

6. The intelligent plasma flow control device for incident shock wave boundary layer interference according to claim 5, characterized in that: The distance between two adjacent electrode pairs is set to 3~5mm.

7. The intelligent plasma flow control device for incident shock wave boundary layer interference according to claim 1, characterized in that: The plasma synthetic jet actuator, the first wall hot line module, and the second wall hot line module are all installed at the bottom of the flat plate, and the surfaces of the plasma synthetic jet actuator, the first wall hot line module, and the second wall hot line module are flush with the surface of the bracket.

8. An intelligent plasma flow control method for incident shock wave boundary layer interference, characterized in that: The intelligent plasma flow control device for incident shock wave boundary layer interference according to any one of claims 1 to 7, wherein the method comprises: Controlling the supply voltage and / or supply frequency of the high-voltage pulse power supply to operate the plasma synthetic jet actuator; Acquiring the state of air transmitted by the first wall heat line module and the second wall heat line module; The supply voltage and / or supply frequency of the high-voltage pulse power supply is adjusted based on the reinforcement learning model and the air state until the shock wave boundary layer interference is completely suppressed.

9. The intelligent plasma flow control method for incident shock wave boundary layer interference according to claim 8, characterized in that: The step of adjusting the supply voltage and / or supply frequency of the high-voltage pulse power supply based on the reinforcement learning model and the air state includes: determining the size of the flow separation zone according to the state of air transmitted by the first wall heat line module and the second wall heat line module; determining whether a difference between a flow separation zone size in a current cycle and a flow separation zone size in a previous cycle is positive, and if so, increasing a reward of the reinforcement learning model; Based on the reinforcement learning model combined with the adjusted reward and the air state, the supply voltage and / or supply frequency of the next cycle of the high-voltage pulse power supply is generated.

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