Long-time drag reduction method for transonic morphing aircraft

Abstract

The application discloses a long-time drag reduction method for a cross-domain variable-configuration aircraft. On the cross-domain variable-configuration aircraft, the differential pressure drag of the aircraft is reduced by high-momentum wall reverse energy self-sustaining synthetic jets, and / or the frictional drag of the aircraft is reduced by low-momentum wall tangential energy self-sustaining synthetic jets. The application is applied to the field of fluid mechanics active flow control, and based on the high-momentum wall reverse energy self-sustaining synthetic jets and / or the low-momentum wall tangential energy self-sustaining synthetic jets, control is exerted on a flow field, thereby reducing the differential pressure drag and / or the frictional drag of the aircraft. The application has the advantages of low energy consumption, no need of additional air source / power source, long-time working in a flight state, strong self-adaptive characteristics for cross-domain non-steady flow fields, controllable and adjustable tangential / reverse jets, and diversified control on the frictional drag and the differential pressure drag of the aircraft.

Description

Technical Field

[0001] This invention relates to the fields of aircraft design, aerodynamics, active flow control in fluid mechanics, and gas discharge technology, specifically a long-term drag reduction method for cross-domain variable-configuration aircraft. Background Technology

[0002] The rapid development of aerospace technology has led to increasingly higher performance requirements for space transportation systems, rendering traditional fixed-configuration aircraft inadequate for the complex space missions of the future. With the advancement of key technologies such as lightweight deformable materials and structures, intelligent sensing and flight control, and active flow regulation, cross-domain variable-configuration aircraft have become a key research area of ​​focus both domestically and internationally in recent years. Cross-domain variable-configuration aircraft refer to a class of aircraft capable of achieving efficient and intelligent, repeatable flight across large airspaces, wide speed ranges, and long distances through continuous configuration changes combined with active flow regulation and intelligent control. This field is one of the most likely to bring about significant changes and disruptive impacts to aerospace technology, and is of great significance for meeting the critical national needs of high-speed civil aviation and scheduled space-to-ground transportation within approximately one hour of global reach.

[0003] To improve the efficiency and accessibility of future civil aviation and air-to-ground transportation, high payload-to-length ultra-long-range flight is one of the key performance characteristics that cross-domain variable-configuration aircraft must possess. The key to achieving high payload-to-length ultra-long-range flight lies in maintaining low-drag, high-efficiency flight under various configurations and environments. Therefore, research on drag reduction technology for cross-domain variable-configuration aircraft is crucial. Active flow control technology, with its wide adaptability, flexible control, and certain adaptive capabilities, is an effective method for solving the drag reduction problem of cross-domain variable-configuration aircraft; however, high energy consumption is its fatal weakness. Cross-domain variable-configuration aircraft typically need to maintain high-speed flight within the atmosphere for extended periods. The cumulative effect of aerodynamic drag results in significant energy loss, so drag reduction technology must also be able to generate a long-term cumulative effect. Short-term local drag reduction is not significant for improving the overall performance of the aircraft, requiring drag reduction methods that can sustain long-term operation. However, active flow control technology often suffers from high power / air consumption and limited operating time due to the need for continuous additional energy injection. This is particularly prominent for active flow control actuators that require drag reduction under high-speed incoming flow conditions and over large areas of different parts of the aircraft. Summary of the Invention

[0004] To address the shortcomings of the prior art, this invention provides a long-term drag reduction method for cross-domain variable-structure aircraft, which enables diversified control of the frictional drag and pressure drag of cross-domain variable-structure aircraft.

[0005] To achieve the above objectives, the present invention provides a long-term drag reduction method for a transdomain variable-structure aircraft. In the transdomain variable-structure aircraft, the pressure drag is reduced by a high-momentum wall reverse energy self-sustaining synthetic jet, and / or the friction drag is reduced by a low-momentum wall tangential energy self-sustaining synthetic jet.

[0006] In one embodiment, the total pressure of the high-momentum wall reverse energy self-sustaining synthetic jet is higher than the total pressure of the incoming flow from the aircraft; and / or

[0007] The total pressure of the low-momentum wall tangential energy self-sustaining synthetic jet is lower than the total pressure of the incoming flow from the spacecraft.

[0008] In one embodiment, a first energy-sustaining synthetic jet exciter is arranged at the leading edge of the aircraft to generate the high-momentum wall-reverse energy-sustaining synthetic jet. This high-momentum wall-reverse energy-sustaining synthetic jet is used to regulate the unsteady airflow and flow field discontinuities at the leading edge, thereby reducing the pressure drag of the aircraft; and / or

[0009] A second energy-sustaining synthetic jet exciter is arranged on the fuselage surface of the aircraft to generate the low-momentum wall tangential energy-sustaining synthetic jet. Based on the low-momentum wall tangential energy-sustaining synthetic jet, the flow vortex, strip structure, and hairpin vortex of the boundary layer under multiphysics field environment are controlled, thereby reducing the frictional drag of the aircraft.

[0010] In one embodiment, when flying within the altitude range of 0-40 km, the unsteady airflow and flow field discontinuity on the windward side are controlled by a high-momentum wall reverse energy self-sustaining synthetic jet, which focuses on reducing the pressure drag of the aircraft.

[0011] When flying at altitudes between 40 and 100 kilometers, the flow vortices, strip structures, and hairpin vortices of the boundary layer in a multiphysics environment are controlled by a low-momentum wall tangential energy self-sustaining synthetic jet, which focuses on reducing the frictional drag of the aircraft.

[0012] In one embodiment, the triggering method for the high-momentum wall reverse energy self-sustaining synthetic jet is as follows:

[0013] The high-momentum wall-side reverse energy self-sustaining synthetic jet is generated by perturbing the flow field through high-frequency anomalous glow discharge and high-frequency laser-induced plasma to produce local high temperatures; and / or

[0014] A mixture of free electrons and positive ions is generated through normal glow discharge. A Lorentz force is generated by the coupling of a magnetic field with this mixture, applying an unsteady, high-repetition-rate directional volume force to the boundary layer sublayer fluid, thus producing the high-momentum wall-side reverse energy self-sustaining synthetic jet; and / or

[0015] The gas is heated and pressurized by spark discharge or arc discharge, and the heated and pressurized gas is ejected at high speed, forming a high-temperature and high-speed jet in the flow field discontinuity interference zone, generating the high-momentum wall reverse energy self-sustaining synthetic jet; and / or

[0016] The high-temperature, high-pressure carbon dioxide gas generated by the semi-Breen cycle active cooling and power generation system of the aircraft forms a high-temperature, high-speed jet in the flow field discontinuity interference zone, thereby generating the high-momentum wall reverse energy self-sustaining synthetic jet.

[0017] In one embodiment, the triggering method for the low-momentum wall tangential energy self-sustaining synthetic jet is as follows:

[0018] A pressurized airflow duct is installed at the nose of the aircraft to introduce the incoming airflow at high altitude, which is then stored in a gas tank for deceleration and cooling. The airflow is then guided to the fuselage surface via a flow valve, forming the low-momentum wall tangential energy self-sustaining synthetic jet; and / or

[0019] The high-temperature, high-pressure carbon dioxide gas generated by the semi-Breen cycle active cooling and power generation system of the aircraft is stored in a gas tank for deceleration and cooling, and then guided to the fuselage surface of the aircraft through a flow valve to form the low-momentum wall tangential energy self-sustaining synthetic jet.

[0020] Compared with the prior art, the present invention has the following beneficial technical effects:

[0021] This invention controls the flow field based on high-momentum wall reverse energy self-sustaining synthetic jets and / or low-momentum wall tangential energy self-sustaining synthetic jets, thereby reducing the pressure drag and / or friction drag of the aircraft. It not only has low energy consumption, but also does not require an additional air source / power source, and has the advantage of long-term operation in flight. It also has strong adaptive characteristics to trans-domain unsteady flow fields. The controllable and adjustable tangential / reverse jets generated can respectively provide diversified control over the friction drag and pressure drag of the aircraft. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the long-term drag reduction structure of the transdomain variable-structure aircraft in an embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of the layout structure of the first energy self-sustaining synthetic jet exciter at the nose of the aircraft in an embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of the layout structure of the first energy self-sustaining synthetic jet exciter on the leading edge of the wing in an embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram of the layout structure of the second energy self-sustaining synthetic jet exciter on the fuselage underside in an embodiment of the present invention;

[0027] Figure 5 This is a first isometric view of the jet generator in an embodiment of the present invention;

[0028] Figure 6 This is a second isometric view of the jet generator in an embodiment of the present invention;

[0029] Figure 7 This is a cross-sectional view of the jet generator in an embodiment of the present invention;

[0030] Figure 8 This is a schematic diagram of the internal structure of the jet generator in an embodiment of the present invention.

[0031] Reference numerals: Structure 1, First plane 101, Second plane 102, Third plane 103, Fourth plane 104, Fifth plane 105, Sixth plane 106, Inlet channel 201, Gas collection chamber 202, First jet channel 203, Second jet channel 204, Third jet channel 205, Discharge electrode 206.

[0032] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0034] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0035] This embodiment discloses a long-term drag reduction method for a cross-domain variable-structure aircraft. On the cross-domain variable-structure aircraft, pressure drag is reduced by a high-momentum wall-end self-sustaining synthetic jet with reverse energy, and / or friction drag is reduced by a low-momentum wall-end self-sustaining synthetic jet with tangential energy. Specifically, the high-momentum wall-end self-sustaining synthetic jet and the low-momentum wall-end self-sustaining synthetic jet reduce drag through coupling with multiple physical fields such as the unsteady pressure field, velocity field, vortex field, and high-temperature field of the aircraft wall. The method focuses on reducing pressure drag in the 0-40 km altitude range and friction drag in the 40-100 km altitude range.

[0036] In this embodiment, the total pressure of the high-momentum wall-backed self-sustaining composite jet is higher than the total pressure of the incoming airflow from the aircraft, while the total pressure of the low-momentum wall-tangentially self-sustaining composite jet is lower than the total pressure of the incoming airflow from the aircraft. Specifically, the total pressure of the high-momentum wall-backed self-sustaining composite jet is 10-20 times the total pressure of the incoming airflow from the aircraft, and the total pressure of the low-momentum wall-tangentially self-sustaining composite jet is 0.5-0.7 times the total pressure of the incoming airflow from the aircraft, or the total pressure of the low-momentum wall-tangentially self-sustaining composite jet is one order of magnitude lower than the total pressure of the incoming airflow from the aircraft.

[0037] In practical implementation, a first energy-sustaining synthetic jet exciter can be arranged on the leading edge of the aircraft (e.g., the nose or wing leading edge) to generate a high-momentum wall-reverse energy-sustaining synthetic jet. This high-momentum wall-reverse energy-sustaining synthetic jet can then be used to regulate the unsteady airflow and flow field discontinuities on the windward side, thereby reducing the pressure drag of the aircraft. Specifically, the jet can weaken the intensity of the flow field discontinuities, reducing the pressure behind the discontinuities, thus lowering the pressure on the aircraft surface and reducing drag. Simultaneously, the jet can interact with the unsteady airflow on the windward side, creating a recirculation zone on the aircraft surface, which can also reduce the surface pressure and drag.

[0038] A second energy-sustaining synthetic jet exciter can also be deployed on the fuselage surface of the aircraft to generate a low-momentum wall tangential energy-sustaining synthetic jet. This low-momentum wall tangential energy-sustaining synthetic jet can then be used to modulate the flow vortices, strip structures, and hairpin vortices of the boundary layer under multiphysics field conditions, thereby reducing the frictional drag of the aircraft. Specifically, the modulating effect of the low-momentum tangential jet increases the boundary layer thickness, thickens the buffer layer, and shifts the logarithmic region outward, resulting in a decrease in average viscous shear stress and thus reducing the frictional drag of the boundary layer.

[0039] Both the first energy-sustaining synthetic jet exciter and the second energy-sustaining synthetic jet exciter consist of several isomorphic and heterogeneous distributed exciter arrays.

[0040] Since the primary drag experienced by a trans-domain variable-structure aircraft varies across different altitude ranges, in this embodiment, when the trans-domain variable-structure aircraft flies within the 0-40 km altitude range, the unsteady airflow and flow field discontinuities on the windward side are controlled by a high-momentum wall-side reverse energy self-sustaining synthetic jet, i.e., the aforementioned first energy self-sustaining synthetic jet exciter is activated to primarily reduce the pressure drag of the aircraft. When the trans-domain variable-structure aircraft flies within the 40-100 km altitude range, the aforementioned second energy self-sustaining synthetic jet exciter is activated, and the flow vortices, strip structures, and hairpin vortices in the boundary layer under a multiphysics environment are controlled by a low-momentum wall-side tangential energy self-sustaining synthetic jet to primarily reduce the frictional drag of the aircraft.

[0041] It is worth noting that both the first and second self-sustaining synthetic jet exciters are arrayed. Specifically, in this embodiment, the first self-sustaining synthetic jet exciters are respectively located at the nose of the aircraft and the leading edge of the wing. At the nose of the aircraft, several first self-sustaining synthetic jet exciters are arranged in a ring array, located within a radius of 15-25 mm from the stagnation point at the nose of the aircraft. Figure 2 As shown; at the leading edge of the wing, several first-energy self-sustaining synthetic jet exciters are distributed in a rectangular or linear array, located within 20mm above and below the windward line at the leading edge of the wing, such as... Figure 3 As shown. The second energy-sustaining synthetic jet exciter is arranged in a matrix array on the underside of the fuselage, positioned relatively close to the nose of the aircraft, specifically within approximately 20%-40% of the aircraft's length. Figure 4 As shown.

[0042] Furthermore, the magnitudes of pressure drag and friction drag experienced by the cross-domain variable-structure aircraft change in real time with variations in flight altitude and operating conditions. Therefore, when the cross-domain variable-structure aircraft flies within an altitude range of 0-40 km, activating part or all of the first energy-sustainable synthetic jet exciter, or optionally activating part of the second energy-sustainable synthetic jet exciter, focuses on reducing both pressure drag and friction drag. When the cross-domain variable-structure aircraft flies within an altitude range of 40-100 km, activating part or all of the second energy-sustainable synthetic jet exciter, or optionally activating part of the first energy-sustainable synthetic jet exciter, focuses on reducing both friction drag and pressure drag. This achieves low-energy active drag reduction. In this embodiment, a neural network algorithm combining RNS / LES hybrid numerical simulation data and shock wave polarimetric analysis model is used to coordinate and match the activation of the first and second energy-sustainable synthetic jet exciters. The specific implementation process is as follows:

[0043] The first step is for the aircraft to obtain information on its flight speed, attitude, and altitude through sensors and then transmit this information to the central processing unit.

[0044] The second step is for the central processing unit to quickly obtain the inviscid flow field structure of the aircraft using the shock wave polar line theory analysis model.

[0045] The third step is to quickly obtain the accurate flow field structure of the aircraft based on the inviscid flow field structure using the RNS / LES hybrid numerical simulation method, thereby obtaining the distribution and proportion of pressure drag and friction drag.

[0046] The fourth step involves substituting the resistance distribution characteristic data into the algorithm and using a data-driven neural network to determine the opening ratio and position of the first and second energy-sustaining synthetic jet exciters.

[0047] refer to Figure 1 In practical implementation, a pressurized airflow duct can be installed at the nose of the aircraft to introduce the incoming airflow at high altitude, which is then stored in a gas tank for deceleration and cooling. The airflow is then guided to the fuselage surface through a flow valve, forming a low-momentum wall tangential energy self-sustaining synthetic jet. Simultaneously, an initial heat collection and power generation module installed at the nose of the aircraft, in the pressurized airflow duct, and in the gas tank generates electrical energy. This energy is then used by a battery and a high-voltage discharge target to act on the motor exciter, causing the gas to heat up and pressurize through spark discharge or arc discharge. The heated and pressurized gas is then ejected at high speed, forming a high-temperature, high-speed jet in the flow field discontinuity interference zone, generating a high-momentum wall reverse energy self-sustaining synthetic jet.

[0048] Of course, in specific applications, other methods can also be used to trigger the self-sustaining composite jet of high momentum wall reverse energy and low momentum wall tangential energy, for example:

[0049] By using high-frequency anomalous glow discharge and high-frequency laser-induced plasma to generate local high temperature, the flow field is disturbed, resulting in a high-momentum wall reverse energy self-sustaining synthetic jet.

[0050] A mixture of free electrons and positive ions is generated by normal glow discharge. The Lorentz force is generated by the coupling effect of the magnetic field with the mixture, and an unsteady high repetition rate directional volume force is applied to the fluid at the bottom of the boundary layer, resulting in a high momentum wall reverse energy self-sustaining synthetic jet.

[0051] The high-temperature, high-pressure carbon dioxide gas generated by the semi-Breen cycle active cooling and power generation system of the aircraft forms a high-temperature, high-speed jet in the flow field discontinuity interference zone, generating a high-momentum wall reverse energy self-sustaining synthetic jet.

[0052] The high-temperature, high-pressure carbon dioxide gas generated by the semi-Breen cycle active cooling and power generation system of the aircraft is stored in a gas tank for deceleration and cooling, and then guided to the fuselage surface of the aircraft through a flow valve to form a low-momentum wall tangential energy self-sustaining synthetic jet.

[0053] This embodiment also discloses a jet exciter for generating low-momentum tangential jets from walls. Specifically, refer to... Figures 5 to 8 In this embodiment, the jet exciter includes a structure 1 comprising a jet structure and a flat wedge structure. The structure 1 includes a first plane 101 at the bottom, a second plane 102 and a third plane 103 at the top, a fourth plane 104 at the tail, and a fifth plane 105 and a sixth plane 106 on the sides. The first plane 101, second plane 102, third plane 103, and fourth plane 104 are connected end-to-end, forming a closed annular structure. The fifth plane 105 and sixth plane 106 cover both sides of the annular structure, and the first plane 101 and third plane 103 are perpendicular to the fourth plane 104, i.e., the first plane 101 and third plane 103 are parallel to each other. The jet structure includes an air intake channel 201, an air collection chamber 202, and a first jet channel 203 disposed inside the structure 1. The air collection chamber 202 is a rectangular cavity, disposed inside the structure 1 and near the tail end of the third plane 103 and the fourth plane 104. The air intake channel 201 also has a rectangular cross-section, with its length parallel to the first plane 101. The first end of the air intake channel 201 is located on the second plane 102, and the second end of the air intake channel 201 is connected to the air collection chamber 202. The length of the first jet channel 203 is perpendicular to the fourth plane 104. Its first end is connected to the air collection chamber 202, and its second end is located in the central region of the fourth plane 104. This allows the airflow to enter the air collection chamber 202 through the air intake channel 201 and then form a low-momentum tangential jet on the surface of the aircraft through the third jet channel 205 in the central region of the fourth plane 104. This results in an increase in the boundary layer thickness, a thicker buffer layer, and an outward shift of the logarithmic region. Consequently, the average viscous shear stress decreases, thus reducing the frictional drag of the boundary layer.

[0054] In a preferred embodiment, the jet structure further includes a second jet channel 204 and a third jet channel 205 disposed inside the structure 1. The first end of the second jet channel 204 is connected to the gas collection chamber 202, and the second end of the second jet channel 204 is located on the fifth plane 105. The first end of the third jet channel 205 is connected to the gas collection chamber 202, and the second end of the third jet channel 205 is located on the sixth plane 106. The second ends of the second jet channel 204 and the third jet channel 205 are inclined towards the top and tail directions of the structure 1, respectively, so that after the airflow enters the gas collection chamber 202 through the air inlet channel 201, it also generates an upwardly inclined entrained jet downstream of the jet exciter on the fifth plane 105 and the sixth plane 106 through the second jet channel 204 and the third jet channel 205, respectively. This, combined with the wall tangential jet generated by the first jet channel 203, further increases the boundary layer thickness, thickens the buffer layer, and shifts the logarithmic region outward, thereby improving the drag reduction effect of the jet exciter.

[0055] More preferably, the jet structure also includes a discharge electrode 206, which is disposed within the gas collecting cavity 202 and electrically connected to an external control device via a pre-embedded wire. By placing the discharge electrode 206 within the gas collecting cavity 202, high-voltage discharge can be selectively controlled during specific applications, thereby controlling the jet effect of the jet structure. For example, when the incoming Mach number of the aircraft is low, the drag reduction requirement of the aircraft is low, and high-voltage discharge by the discharge electrode 206 is not required; the jet generated by the air intake channel 201 itself is sufficient to meet the requirements. When the incoming Mach number of the aircraft is high, the drag reduction requirement of the aircraft is high, and the jet generated by the air intake channel 201 itself is insufficient to meet the requirements. In this case, the discharge electrode 206 can be controlled to perform high-voltage discharge, and the energy and frequency of the discharge can be modulated according to the requirements, thereby controlling the jet energy and frequency of the jet structure to meet the current drag reduction requirements of the aircraft.

[0056] It is worth noting that, in specific applications, the connection between the air intake channel 201 and the air collection chamber 202 should be set as a stepped structure, and the height of the bottom wall of the air collection chamber 202 should be lower than the bottom wall of the air intake channel 201. At the same time, the discharge electrode 206 should be fixed to the bottom wall or the stepped wall of the air collection chamber 202, keeping the height of the discharge electrode 206 lower than the bottom wall of the air intake channel 201 to prevent the air intake airflow from interfering with the discharge of the discharge electrode 206.

[0057] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A long-duration drag reduction method for a transdomain variable-structure aircraft, characterized in that, In a cross-domain variable-structure aircraft, pressure drag is reduced by high-momentum wall reverse energy self-sustaining synthetic jet, and friction drag is reduced by low-momentum wall tangential energy self-sustaining synthetic jet. The total pressure of the high-momentum wall reverse energy self-sustaining synthetic jet is higher than the total pressure of the incoming flow from the aircraft. The total pressure of the low-momentum wall tangential energy self-sustaining composite jet is lower than the total pressure of the incoming flow from the aircraft; A first energy-sustaining synthetic jet exciter is arranged at the leading edge of the aircraft to generate the high-momentum wall reverse energy-sustaining synthetic jet. Based on the high-momentum wall reverse energy-sustaining synthetic jet, the unsteady airflow and flow field discontinuity on the windward side are controlled, thereby reducing the pressure drag of the aircraft. A second energy-sustaining synthetic jet exciter is arranged on the fuselage surface of the aircraft to generate the low-momentum wall tangential energy-sustaining synthetic jet, so as to regulate the flow vortex, strip structure and hairpin vortex of the boundary layer under the multiphysics field environment based on the low-momentum wall tangential energy-sustaining synthetic jet, thereby reducing the frictional drag of the aircraft. A pressurized airflow duct is installed at the nose of the aircraft to introduce the incoming airflow at high altitude, which is stored in a gas tank for deceleration and cooling. The airflow is then guided to the fuselage surface of the aircraft through a flow valve to form the low-momentum wall tangential energy self-sustaining synthetic jet. Simultaneously, the starting heat collection power generation module installed in the aircraft's nose, pressurized airflow pipeline, and gas storage tank generates electrical energy, and the battery and high-voltage discharge target act on the motor exciter, so that the gas is heated and pressurized through spark discharge or arc discharge. The heated and pressurized gas is ejected at high speed, forming a high-temperature and high-speed jet in the flow field discontinuity interference zone, generating a high-momentum wall reverse energy self-sustaining synthetic jet. When flying within the altitude range of 0-40 km, the unsteady airflow and flow field discontinuity on the windward side are controlled by high momentum wall reverse energy self-sustaining synthetic jet, which focuses on reducing the pressure drag of the aircraft. When flying at altitudes between 40 and 100 kilometers, the flow vortices, strip structures, and hairpin vortices of the boundary layer in a multiphysics environment are controlled by a low-momentum wall tangential energy self-sustaining synthetic jet, which focuses on reducing the frictional drag of the aircraft.

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