High-speed aircraft based on micro-scale tangential gas film and drag reduction and heat reduction design method thereof

Abstract

The invention discloses a high-speed aircraft based on a micro-scale tangential gas film and a resistance and heat reduction design method of the high-speed aircraft. The high-speed aircraft based on the micro-scale tangential gas film comprises a first gas film generator, the first gas film generator is laid at a first thermal protection position on the surface of the high-speed aircraft, a first spraying seam with a first height is formed in the surface of the first gas film generator and the surface of the high-speed aircraft, and a second spraying seam with a second height is formed in the surface of the high-speed aircraft; the first gas film generator injects a gaseous or liquid coolant into the first spray seam to form a gaseous film, and the effective cooling length of the gaseous film is a first length.

Description

Technical Field

[0001] The present invention relates to the field of aerospace technology, and in particular to a high-speed aircraft based on a micro-scale tangential air film and a drag and heat reduction design method thereof. Background Art

[0002] Hypersonic aircraft refers to aircraft with a flight speed greater than Mach 5. When a hypersonic aircraft flies at a hypersonic speed in a dense atmosphere, the airflow in the atmosphere will produce strong friction with the surface of the hypersonic aircraft, and the kinetic energy lost by the airflow in the boundary layer on the surface of the hypersonic aircraft will be converted into heat energy, causing the gas temperature in the boundary layer on the surface of the hypersonic aircraft to rise.

[0003] However, the higher temperature in the boundary layer of the hypersonic aircraft surface will ablate the surface material of the hypersonic aircraft, thereby reducing the strength and structural integrity of the hypersonic aircraft surface. At the same time, the ablation caused by the higher temperature in the boundary layer of the hypersonic aircraft surface will also change the shape and texture of the hypersonic aircraft surface, thereby affecting its aerodynamic performance (including reducing lift and increasing drag), flight performance and fuel efficiency. In addition, for reusable hypersonic aircraft, the ablation caused by the higher temperature in the boundary layer of the hypersonic aircraft surface will also increase the maintenance and repair costs of the hypersonic aircraft, and may pose a potential threat to the flight safety of hypersonic aircraft.

[0004] Therefore, how to take safe, effective and low-cost thermal protection measures on the surface of a hypersonic vehicle is a technical problem to be solved by the present invention. Summary of the invention

[0005] The purpose of the present invention is to provide a high-speed aircraft based on micro-scale tangential air film and a design method for reducing drag and heat thereof. A gaseous film is applied to the wall of a hypersonic (supersonic) aircraft, which not only reduces heat and drag on the surface of the hypersonic (supersonic) aircraft, but also safely, efficiently and cost-effectively thermally protects the outer surface of the hypersonic (supersonic) aircraft.

[0006] According to one aspect of the present invention, at least one embodiment provides a method for designing drag reduction and heat reduction, comprising: obtaining a thermal protection area on the surface of a high-speed aircraft based on a microscale tangential air film; determining the type and number of air film generators arranged in the thermal protection area based on at least one effective cooling length of at least one air film generator.

[0007] According to another aspect of the present invention, at least one embodiment further provides a thermal protection device, comprising: a processor, suitable for implementing various instructions; and a memory, suitable for storing multiple instructions, wherein the instructions are suitable for being loaded and executed by the processor: the drag reduction and heat reduction design method of the present invention.

[0008] According to another aspect of the present invention, at least one embodiment further provides a computer-readable non-volatile storage medium storing computer program instructions, and when the computer executes the program instructions, the drag reduction and heat reduction design method of the present invention is executed.

[0009] According to another aspect of the present invention, applying the drag reduction and heat reduction design method of the present invention, at least one embodiment of the present invention further provides a high-speed aircraft based on a micro-scale tangential air film, comprising: a first air film generator, wherein the first air film generator is laid at a first heat protection position on the surface of the high-speed aircraft, a first spray gap of a first height is provided between the first air film generator and the surface of the high-speed aircraft, the first air film generator injects a gaseous or liquid coolant at the first spray gap to form a gaseous film, and the effective cooling length of the gaseous film is a first length.

[0010] The present invention designs a tangential spray seam of a certain thickness on the surface of the hypersonic aircraft in the above manner, and injects a gaseous or liquid coolant into the spray seam to form a tangential gaseous film. The gaseous film can lift the boundary layer on the surface of the hypersonic aircraft, and better avoid the direct friction between the high-speed mainstream and the surface of the hypersonic aircraft in the flight state, thereby achieving the purpose of cooling. At the same time, the original friction between the high-speed mainstream and the solid wall of the hypersonic aircraft in the flight state is transformed into friction between the high-speed mainstream and the low-speed gaseous film; since the friction between gas and gas is much smaller than the friction between gas and solid wall, applying a gaseous film on the surface of the hypersonic aircraft can also achieve the effect of reducing resistance, thereby improving the fuel efficiency of the hypersonic aircraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0012] Figure 1 is a schematic diagram of a thermal protection device according to an embodiment of the present invention;

[0013] Figure 2 is a flow chart of a drag reduction and heat reduction design method according to an embodiment of the present invention;

[0014] Figure 3 is a top view of the outer surface of a high-speed aircraft based on a micro-scale tangential air film to which an air model generating device is applied according to an embodiment of the present invention;

[0015] Figure 4is a schematic diagram of a high-speed aircraft surface based on a micro-scale tangential air film with a tangential air model according to an embodiment of the present invention;

[0016] Figure 5 Schematic diagram of gas film cooling principle according to an embodiment of the present invention. DETAILED DESCRIPTION

[0017] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Generally speaking, the thermal protection measures taken on the surface of hypersonic aircraft can be divided into passive thermal protection and active thermal protection. Passive thermal protection is to select high temperature resistant and ablation resistant materials and install them on the surface of hypersonic aircraft to reduce heat conduction on the surface of hypersonic aircraft and provide protection and heat insulation effects. Active thermal protection refers to the use of some active mechanisms to control the heat transfer on the surface of hypersonic aircraft and reduce the degree of heat exposure of materials to provide more effective thermal protection.

[0019] Passive thermal protection, commonly used methods are: (1) coating thermal protection coatings, these thermal protection coatings are usually composed of ceramic materials or metal materials, and can work stably in high temperature environments; (2) installing thermal insulation corrugated boards, the internal structure of these thermal insulation corrugated boards is usually made of thermal insulation materials, which can reduce heat conduction and heat insulation, while providing a certain structural strength. The inventors found that: thermal protection coatings or thermal insulation corrugated boards are usually made of high-density materials and are relatively heavy. If these materials are added to the surface of hypersonic aircraft, the total weight of the hypersonic aircraft will increase, which will have a negative impact on the flight performance and fuel efficiency of the hypersonic aircraft; thermal protection coatings or thermal insulation corrugated boards are expensive, and the installation of these materials will increase manufacturing costs and maintenance costs. In addition, for reusable hypersonic aircraft, the thermal protection coatings or thermal insulation corrugated boards installed are affected by environmental factors such as wind, sun, high temperature, and high-speed flight, and their durability will deteriorate, requiring regular inspection, maintenance and replacement.

[0020] Active thermal protection is commonly used in the following ways: (1) Transpiration cooling, which sprays cooling gas or liquid onto the surface of a hypersonic vehicle through a small hole array or breathable material to absorb heat and reduce the surface temperature; (2) Convection cooling, which allows cooling gas or liquid to flow through a channel designed under the surface of the hypersonic vehicle, and removes heat from the surface of the hypersonic vehicle through convection heat transfer. The inventors found that for transpiration cooling, it is a challenge to ensure uniform cooling on the entire hot surface of a hypersonic vehicle, because the transpiration of the small hole array may cause uneven temperature on the hot surface of the hypersonic vehicle, thereby affecting the effect of thermal protection; and the breathable material is easily blocked by impurities or other impurities generated by ablation of other parts, resulting in cooling failure. The inventors found that: for convection cooling, since the channels on the lower surface of the hypersonic aircraft cannot be arranged continuously, uniform cooling cannot be guaranteed. If there are too many channels, the structural strength of the aircraft surface will be affected. When the flight speed of the hypersonic aircraft is too high, that is, the temperature of the outer surface of the hypersonic aircraft is too high, the effect of controlling the surface temperature of the hypersonic aircraft through convection heat transfer of the coolant is poor.

[0021] Based on in-depth research on thermal protection measures for hypersonic vehicles, at least one embodiment of the present invention provides a thermal protection device, such as Figure 1 As shown, it includes: a processor 101, suitable for implementing various instructions; and a memory 103, suitable for storing multiple instructions, and the instructions are suitable for being loaded and executed by the processor 101: the drag reduction and heat reduction design method developed by the present invention (or referred to as the thermal protection method of the aircraft surface, or referred to as the hypersonic drag reduction and heat reduction design method, or referred to as the high-speed aircraft drag reduction and heat reduction design method based on micro-scale tangential air film, which will be described in detail later in this article). The high-speed aircraft can also be referred to as a hypersonic aircraft or a high-sonic aircraft or a high-speed aircraft based on a micro-scale tangential air film.

[0022] The processor 101 may be any applicable processor, such as a central processing unit, a microprocessor, an embedded processor, etc., and may adopt an architecture such as X86 or ARM. The memory 103 may be any applicable storage device, such as a non-volatile storage device, including but not limited to a magnetic storage device, a semiconductor storage device, an optical storage device, etc., and may be arranged as a single storage device, a storage device array, or a distributed storage device, which is not limited in the embodiments of the present invention.

[0023] In addition, the present invention can also include a computer-readable non-volatile storage medium in the thermal protection device. The embodiment of the present invention also provides at least a computer-readable non-volatile storage medium that stores computer program instructions. When the computer executes the program instructions, it executes: the drag reduction and heat reduction design method developed by the present invention (or the thermal protection method for the surface of the aircraft, or the drag reduction and heat reduction design method for high-speed aircraft based on micro-scale tangential air film, which will be described in detail later in this article).

[0024] In the operating environment of the above-mentioned thermal protection device and / or computer-readable non-volatile storage medium of the present invention, at least one embodiment of the present invention further provides a drag reduction and heat reduction design method, such as Figure 2 It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order from that here, which may include the following steps:

[0025] Step S202, obtaining a thermal protection area on the surface of a high-speed aircraft based on a micro-scale tangential air film;

[0026] Step S204: determining the type and quantity of the air film generators arranged in the heat protection area according to at least one effective cooling length of at least one air film generator.

[0027] The present invention is not only for the flat-plate-shaped high-speed aircraft surface, but also for various complex high-speed aircraft surfaces such as arc-shaped (such as cylinders) and surfaces with curvature (such as spheres). Through the above method, the type and number of air film generators (i.e., gaseous film generators) that need to be arranged in the thermal protection area of ​​the hypersonic aircraft surface are determined, and then the thermal protection position can be selected in the thermal protection area of ​​the high-speed aircraft surface based on the micro-scale tangential air film to apply and lay the air film generator. The air film generator injects a very small mass flow of gaseous or liquid coolant into the inner layer of the boundary layer on the surface of the hypersonic aircraft, which can achieve the cooling and drag reduction of the hypersonic aircraft surface. At the same time, arranging an air film generator on the surface of a hypersonic aircraft is a safe, effective and low-cost thermal protection measure.

[0028] By applying the hypersonic drag reduction and heat reduction design method of the present invention, after laying at least one (assuming that there are N, N ≥ 1) air film generator on the surface of a high-speed aircraft based on a micro-scale tangential air film, a high-speed aircraft based on a micro-scale tangential air film of the present invention can be formed, wherein the air film generator is a device that generates a gas film. At least one embodiment of the present invention also provides a high-speed aircraft based on a micro-scale tangential air film, such as Figure 3 As shown, including:

[0029] The first air film generator 301 is laid at a first heat protection position on the surface of the high-speed aircraft, and a first spray gap of a first height is arranged between the first air film generator 301 and the surface of the high-speed aircraft. The first air film generator 301 injects gaseous or liquid coolant into the first spray gap to form a gaseous film, and the effective cooling length of the gaseous film is a first length.

[0030] The second air film generator 303 is arranged at a second heat protection position on the surface of the high-speed aircraft, the second air film generator 303 is separated from the first air film generator 301 by a first length, and the opening of the first spray gap faces the second air film generator 303; a second spray gap of a second height is arranged between the second air film generator 303 and the surface of the high-speed aircraft, and the second air film generator 303 injects a gaseous or liquid coolant into the second spray gap to form a gaseous film, and the effective cooling length of the gaseous film is the second length.

[0031] A third air film generator 305, wherein the third air film generator 305 is laid at a third heat protection position on the surface of the high-speed aircraft, the third air film generator 305 is separated from the second air film generator 303 by a second length, and the opening of the second spraying slot is oriented toward the third air film generator 305; a third spraying slot at a third height is provided between the third air film generator 305 and the surface of the high-speed aircraft, the third air film generator 305 injects a gaseous or liquid coolant into the third spraying slot to form a gaseous film, and the effective cooling length of the gaseous film is a third length;

[0032] …

[0033] The Nth air film generator 30 (2N-1) is arranged at the Nth heat protection position on the surface of the high-speed aircraft, the Nth air film generator 30 (2N-1) is separated from the N-1th air film generator 30 (2N-3) by the N-1th length, and the opening of the N-1th spray seam faces the Nth air film generator 30 (2N-1); the Nth air film generator 30 (2N-1) and the surface of the high-speed aircraft are provided with an Nth spray seam at an Nth height, the Nth air film generator 30 (2N-1) injects a gaseous or liquid coolant into the Nth spray seam to form a gaseous film, and the effective cooling length of the gaseous film is the Nth length.

[0034] The present invention designs a tangential spray seam of a certain thickness on the surface of the hypersonic aircraft in the above manner, and injects a gaseous or liquid coolant into the spray seam to form a tangential gaseous film. The gaseous film can lift the boundary layer on the surface of the hypersonic aircraft, and better avoid the direct friction between the high-speed mainstream and the surface of the hypersonic aircraft in the flight state, thereby achieving the purpose of cooling. At the same time, the original friction between the high-speed mainstream and the solid wall of the hypersonic aircraft in the flight state is transformed into friction between the high-speed mainstream and the low-speed gaseous film; since the friction between gas and gas is much smaller than the friction between gas and solid wall, applying a gaseous film on the surface of the hypersonic aircraft can also achieve the effect of reducing resistance, thereby improving the fuel efficiency of the hypersonic aircraft.

[0035] It should be noted that the first air film generator 301, the second air film generator 303, ..., the Nth air film generator 30 (2N-1) can be the same type of air film generator, that is, the spray gap heights and effective cooling lengths of the multiple air film generators can be completely consistent. If the first air film generator 301, the second air film generator 303, ..., the Nth air film generator 30 (2N-1) are of different types, the various types of air film generators can refer to the method / principle for calculating the spray gap height and effective cooling length of the first air film generator 301, and adaptively calculate their respective spray gap heights and effective cooling lengths. At the same time, for each air film generator, such as Figure 4 As shown, 1 is an air film generator for generating a gaseous film, 2 is a gaseous film, 3 is a high-speed aircraft wall based on a micro-scale tangential air film, 4 is a pressure sensor, 5 is a pipeline (for transporting a coolant), 6 is a control system, 7 is an electromagnetic valve (for controlling the mass flow rate of the coolant), and 8 is a coolant storage system (for storing the coolant); the control system 6 controls the opening and closing degree of the electromagnetic valve 7 according to the pressure measured by the pressure sensor 4, thereby controlling the mass flow rate of the coolant.

[0036] For example, the first air film generator 301 obtains the first height of the first nozzle by the following method: obtaining the first boundary layer of the first thermal protection position in the flight state, wherein the first boundary layer includes an inner layer and an outer layer, and the inner layer includes a troposphere and a viscous bottom layer; determining the first height by the thickness of the inner layer or the thickness of the viscous bottom layer, wherein the thickness of the inner layer or the thickness of the viscous bottom layer is corrected by combining theoretical calculation, wind tunnel test and / or numerical simulation. The thickness of the inner layer is about 10% to 20% of the thickness of the first boundary layer, and the thickness of the inner layer is in the sub-millimeter order, and the thickness of the viscous bottom layer is about 1% of the thickness of the first boundary layer, and the thickness of the viscous bottom layer is in the micrometer order.

[0037] It can be seen that the most critical thing in applying and laying an air film generator on the surface of a hypersonic aircraft is to determine the height of the spray seam of the air film generator, which is determined by the height of the internal stratification of the boundary layer at the thermal protection position (sub-millimeter or tens of micrometers). In other words, the spray seam can also be called a tangential groove on the surface of a high-speed aircraft based on a micro-scale tangential air film, and the tangential groove is not easily blocked by upstream ablation impurities or other impurities. Example: First, the present invention obtains the boundary layer thickness (such as the thickness of the inner layer or the thickness of the viscous bottom layer) at the position requiring thermal protection under flight conditions according to the boundary layer thickness calculation formula, numerical simulation or wind tunnel experiment; secondly, the present invention determines the spray seam height according to the thickness of the inner layer or the thickness of the viscous bottom layer, that is, sub-millimeter / micrometer level.

[0038] For example, the first air film generator 301 obtains the first length by: using Determine a first length, wherein the first length is corrected by combining theoretical calculation, wind tunnel test and / or numerical simulation, x represents the first length, h represents the first height, δ 1 is the compressible mixing layer growth rate at the first thermal protection position in flight, δ 2 is the laminar boundary layer thickness at the first thermal protection position in flight, r = u 1 / u 2 ,u 1 is the velocity of the external mainstream at the first thermal protection position in the flight state, u 2 is the velocity of the gas film ejected by the first air film generator in the flight state, s = ρ 1 / ρ 2 , ρ 1 is the density of the external mainstream at the first thermal protection position in the flight state, ρ 2 is the density of the gaseous film ejected by the first air film generator in flight, v is the kinematic viscosity coefficient of the high-speed aircraft, u e is the velocity of the gaseous film ejected by the first air film generator.

[0039] It can be seen that when applying and laying an air film generator on the surface of a hypersonic aircraft, it is also necessary to determine the effective cooling length of the air film generator to form a gaseous film by injecting gaseous or liquid coolant at the nozzle. In other words, the gaseous film is also called a tangential air film on the surface of a high-speed aircraft based on a micro-scale tangential air film. The tangential air film can achieve cooling of a certain distance downstream (unlike the existing sweating cooling technology that only achieves cooling of the sweating area), and the consumption of the mass flow rate of the cooling fluid is relatively small. For example: First, the effective cooling length of the gaseous film is the horizontal coordinate of the intersection of the lower boundary of the mixing layer and the boundary layer of the hypersonic aircraft in flight. The analysis is as follows: From Figure 5It can be seen from the diagram of the principle of gas film cooling that the gas film and the external mainstream shear each other to produce a mixing layer, which is approximately considered to develop from the position where the two contact each other; due to the existence of viscosity, the gas film produces a boundary layer on the surface of the hypersonic aircraft. When the boundary layer on the surface of the hypersonic aircraft intersects with the lower boundary of the mixing layer, the high-temperature mixed gas begins to contact the surface of the hypersonic aircraft. At this time, the surface temperature of the hypersonic aircraft rises and the cooling of the gas film fails. Therefore, the horizontal coordinate of the intersection of the lower boundary of the mixing layer and the boundary layer on the surface of the hypersonic aircraft can be regarded as the effective cooling length of the gas film. Secondly, the theoretical prediction of the effective cooling length of the gas film: (1) The development of the mixing layer thickness with the flow distance is clarified. Through a large number of experiments and numerical calculations, the incompressible mixing layer growth rate λ is determined. 1 The empirical calculation formula Constant C δ ≈0.17. The above formula is only applicable to the calculation of the growth rate of the incompressible mixing layer. In reality, the mixing layer generated by the interaction between the hypersonic mainstream and the gas film is highly compressible. (2) The calculation formula for the growth rate of the compressible mixing layer is clarified. Given that the growth rate λ of the compressible mixing layer is 2 and the growth rate λ of the incompressible mixing layer 1 There is also the following relationship: in, a 1 and a 2 are the sound velocities of the mainstream and gaseous film, respectively. When Mc>2, f(Mc)≈0.2, so the growth rate of the compressible mixing layer can be approximately expressed as: The formula for calculating the thickness of the laminar boundary layer is: (3) In summary, the equation set developed by the present invention can be obtained to calculate the effective cooling length of the gas film.

[0040] The present invention arranges spray slots reasonably on the wall of a hypersonic aircraft according to the effective cooling length of a gaseous film in the above manner, injects a gaseous or liquid coolant into the inner layer of the wall boundary layer, that is, injects the gaseous film tangentially into the inner layer of the hypersonic aircraft wall boundary layer, that is, applies a gaseous film on the wall of the hypersonic aircraft, and forms a high-speed aircraft based on a micro-scale tangential gas film, which not only reduces heat and drag on the surface of the hypersonic aircraft, but also safely, efficiently and cost-effectively thermally protects the outer surface of the hypersonic aircraft.

[0041] The present invention has been verified through relevant wind tunnel tests and numerical calculations, indicating that the surface temperature of the optical window can be reduced, while the wall friction of the hypersonic vehicle can be reduced, thus achieving the expected design goals and being technically feasible.

[0042] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0043] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0044] As used herein, the term "and / or" placed between a first entity and a second entity means (1) the first entity, (2) the second entity, and (3) one of the first entity and the second entity. Multiple entities listed with "and / or" should be interpreted in the same manner, that is, "one or more" of the connected entities. Other entities may exist outside the entities specifically identified by the "and / or" clause, whether related or unrelated to those entities specifically identified. Therefore, as a non-limiting example, when used in conjunction with open language such as "includes", a reference to "A and / or B" may refer to only A (optionally including entities other than B) in one specific instance; only B (optionally including entities other than A) in another specific instance; and both A and B (optionally including other entities) in another specific instance. The entities may refer to components, actions, structures, steps, operations, values, etc.

[0045] As used herein, the phrase "at least one" in relation to a list of one or more entities should be understood to mean selecting at least one entity from any one or more entities in the list of entities, but not necessarily including at least one entity from each or every entity specifically listed in the list of entities, and not excluding any combination of entities in the list of entities. This definition also allows that entities may optionally exist other than the entities specifically identified in the list of entities referred to by the phrase "at least one", whether related or unrelated to those entities specifically identified. Thus, as a non-limiting example, "at least one of A and B" (or equivalently, "at least one of A or B" or equivalently "at least one of A and / or B") may refer in one specific instance to at least one A, optionally including more than one A, without B (and optionally including entities other than B); in another specific instance, at least one B, optionally including more than one B, without A (and optionally including entities other than A); in another specific instance, at least one A, optionally including more than one A, and at least one B, optionally including more than one B (and optionally including other entities). In other words, the phrases "at least one", "one or more", and "and / or" are conjunctive and disjunctive open-ended expressions in operation. For example, "at least one of A, B, and C", "at least one of A, B, or C", "one or more of A, B, and C", "one or more A, B, or C", and "A, B, and / or C" may represent A alone, B alone, C alone, A and B together, A and C together, B and C together, A, B, and C together, and any of the above in combination with at least one other entity, as appropriate.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A drag reduction and heat reduction design method, characterized in that: include: Obtain the thermal protection area of ​​the high-speed aircraft surface based on micro-scale tangential air film; The type and quantity of the air film generators arranged in the heat protection area are determined according to at least one effective cooling length of at least one air film generator.

2. A thermal protection device comprising: a processor adapted to implement the instructions; And a memory, suitable for storing a plurality of instructions, wherein the instructions are suitable for being loaded and executed by a processor: the drag reduction and heat reduction design method as claimed in claim 1.

3. A computer-readable non-volatile storage medium storing computer program instructions, when the computer executes the program instructions, it executes: the drag reduction and heat reduction design method as claimed in claim 1.

4. A high-speed aircraft based on micro-scale tangential air film, using the drag reduction and heat reduction design method as claimed in claim 1, characterized in that: include: A first air film generator, wherein the first air film generator is laid at a first heat protection position on the surface of the high-speed aircraft, a first spray gap of a first height is arranged between the first air film generator and the surface of the high-speed aircraft, the first air film generator injects a gaseous or liquid coolant into the first spray gap to form a gaseous film, and the effective cooling length of the gaseous film is a first length.

5. The high-speed flying vehicle based on micro-scale tangential air film according to claim 4, characterized in that: The first height is obtained by: Acquire a first boundary layer at a first thermal protection position in a flight state, wherein the first boundary layer includes an inner layer and an outer layer, and the inner layer includes a logarithmic layer and a viscous bottom layer; The first height is determined by the thickness of the inner layer or the thickness of the adhesive bottom layer, wherein the thickness of the inner layer or the thickness of the adhesive bottom layer is obtained and corrected by combining theoretical calculation, wind tunnel test and / or numerical simulation.

6. The high-speed flying vehicle based on micro-scale tangential air film according to claim 5, characterized in that: The thickness of the inner layer is 10% to 20% of the thickness of the first boundary layer, which is in the sub-millimeter order. The thickness of the viscous bottom layer is 1% of the thickness of the first boundary layer, which is in the micrometer order.

7. The high-speed flying vehicle based on micro-scale tangential air film according to claim 4, characterized in that: Obtaining the first length includes: use Determine a first length, wherein the first length is corrected by combining theoretical calculation, wind tunnel test and / or numerical simulation, x represents the first length, h represents the first height, δ1 is the compressible mixing layer growth rate of the first thermal protection position in the flight state, δ2 is the laminar boundary layer thickness of the first thermal protection position in the flight state, r=u1 / u2, u1 is the velocity of the external mainstream at the first thermal protection position in the flight state, u2 is the velocity of the gas film ejected by the first air film generator in the flight state, s=ρ1 / ρ2, ρ1 is the density of the external mainstream at the first thermal protection position in the flight state, ρ2 is the density of the gas film ejected by the first air film generator in the flight state, v is the kinematic viscosity coefficient of the high-speed aircraft, u e is the velocity of the gaseous film ejected by the first air film generator.

8. The high-speed flying vehicle based on micro-scale tangential air film according to claim 4, characterized in that: Also includes: A second air film generator, wherein the second air film generator is laid at a second heat protection position on the surface of the high-speed aircraft, the second air film generator is separated from the first air film generator by a first length, and the opening of the first spray slot faces the second air film generator.

9. The high-speed flying vehicle based on micro-scale tangential air film according to claim 8, characterized in that: The second air film generator and the surface of the high-speed aircraft are provided with a second spray gap at a second height. The second air film generator injects gaseous or liquid coolant into the second spray gap to form a gaseous film. The effective cooling length of the gaseous film is a second length.

10. The high-speed flying vehicle based on micro-scale tangential air film according to claim 9, characterized in that: Also includes: A third air film generator, wherein the third air film generator is laid at a third heat protection position on the surface of the high-speed aircraft, the third air film generator is separated from the second air film generator by a second length, and the opening of the second spray slot faces the third air film generator.

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