CN116186904B

CN116186904B - Mechanical overall aerodynamic layout method with lifting surface moving in fluid

Info

Publication number: CN116186904B
Application number: CN202310399807.6A
Authority: CN
Inventors: 朱上翔
Original assignee: Beijing Zhongjia Technology Co ltd
Current assignee: Beijing Zhongjia Technology Co ltd
Priority date: 2023-04-14
Filing date: 2023-04-14
Publication date: 2023-07-21
Anticipated expiration: 2043-04-14
Also published as: CN116186904A

Abstract

The invention provides a mechanical overall aerodynamic layout method with lifting surfaces moving in a fluid, comprising: solving a Navier-Stokes equation according to Bernoulli's formula or by utilizing CFD software, or through wind tunnel experiments and flight tests, the load distribution, the pneumatic resultant force and the direction and speed direction relation of the wing airfoil are obtained, the front edge and the rear edge of the wing airfoil are reversely distributed, the airfoil is inverted by 180 degrees, and the zero-lift resistance and the induced resistance of the whole machine are calculated; calculating the lift-drag ratio and the residual thrust coefficient of the whole computer; and calculating the flight performance, the maneuverability, the stability and the flight quality. The invention relatively changes the direction of the wing profile or the projection component force of the wing induced force in the flying speed direction, under the same forward flying speed and the same attack angle, the aerodynamic resultant force vector on the wing profile and the direction relative to the chord line of the wing profile are not changed, but the direction of the projection component force of the resultant force in the speed direction is changed by 180 degrees, and the induced resistance is changed into the induced thrust, so that the total resistance of the aircraft is greatly reduced.

Description

Mechanical overall aerodynamic layout method with lifting surface moving in fluid

Technical Field

The invention relates to the technical field of aerodynamic layout design, in particular to an overall aerodynamic layout method provided with an airfoil lifting surface device; and more particularly to a mechanical overall aerodynamic layout method with lifting surfaces moving in a fluid.

Background

Machines moving in fluids (air and water), such as various types of aircraft, underwater craft, submarines, etc., have been invented and used for a long time in human history, and the application scenarios are very wide. The moving machinery in the fluid such as the airplane, the ship and the like provides an extremely important tool for the travel of human beings, the economic development and the military use.

At present, the method for designing the transportation devices is mature and perfect, and particularly various aircrafts flying in the atmosphere, and the method has been developed for hundreds of decades. In addition to power systems, materials, avionics, automatic control, artificial intelligence, and communication technologies, the overall layout is also changing day by day, wherein the overall aerodynamic layout has a development course from a normal aircraft layout, a tailless layout, a duck-type layout, a flying wing type layout to a recently published wing body combined aircraft, the aerodynamic layout occupies a very important position in the overall layout, and the advantages and disadvantages of the aerodynamic layout design are directly related to the performance, efficiency, economy and safety of the whole aircraft.

To optimize performance and improve efficiency, scientists have first focused on developing wing airfoils, and universities or institutional scientists have developed hundreds to thousands of very good airfoils. The requirements of various purposes and various application scenes are met, and the main purpose of the device is to increase lift and drag resistance and increase lift-drag ratio.

However, current research on wing airfoils has almost reached an upper limit, the potential has almost been dug out, and further performance is improved in terms of increasing lift or reducing drag, requiring additional paths.

The overall aerodynamic layout is generally defined today as: "mainly selects the layout form of airfoil, wing and tail and its geometric parameters". The layout of the wings and the tail wings is also limited to the front and back positions and the high and low positions. In the history of aircraft design, the birds of the da vinci must fly freely in the sky, and he has carefully studied the birds for the reason of flying in the air due to the wings of the birds. He asserts: if a human being is able to design a machine with a device resembling a bird wing, and with a tail that ensures stable flying behind, it is possible for the human being to achieve a flying dream by means of such a man-machine. The da vinci then designed the first bird-like fixed wing aircraft for humans, see fig. 1.

The appearance of a da vinci aircraft is shown in fig. 1 as a bird and a modern fixed wing aircraft after 500 years. Although 500 years have passed, the general structure, layout (relative positions of wings and fuselage and tail wing, and fore-aft arrangement of wings, bodies and tails of birds, positions and directions of wings and fore-aft edges of wings) of normal fixed-wing aircraft is now almost completely similar! In particular, the position (i.e., relative orientation) of the wing and the wing leading and trailing edges has never changed for 500 years. After da vinci, the uk aviation predecessor, aerodynamic founder kerr mines (1773-1857) proposed the principle of modern fixed wing aircraft in 1853, indicating that: fixed wing aircraft must possess independent lift generating mechanisms, independent thrust generating mechanisms, and independent control surfaces. The current layout of fixed wing aircraft derives from simulating the flying of bird wings. After 36 years, german engineers Li Lin Dall (1848-1896) written in 1889 as a well-known "bird flight-aviation foundation" which discusses the characteristics of bird flight, point out that the wing also has an arcuate section like a wing to obtain a larger lift force, thereby confirming the reasonable form of a curved wing.

Compared with all modern normal fixed wing aircraft, the front and rear edges of the wing section of the overall aerodynamic layout are the same as the front and rear edges of the aircraft body of the Davinci aircraft before 500 years, and the front aircraft is unchanged, which is an inertial thinking, and the mode of simulating birds to place the front and rear edges of the wing is considered to be astronomical, reasonable, free from errors, and free from trying to use the custom layout of five centuries.

Because the bernoulli principle was born in 1738 years, more than 200 years later than the first fixed wing aircraft of the da vinci design, the da vinci was not likely to apply to the bernoulli principle to direct the aerodynamic layout of the aircraft he designed. Kley and Li Lin dar, although they last more than 100 years after bernoulli, are faithful followers to the da vinci and also guide them on the design of an aircraft using the principle of avian flight, so no study was made on the relative orientation of the wing bodies, but rather the aerodynamic layout of the da vinci aircraft was followed. As to the pneumatic layout of the wing body relative orientation, the latter general designer is not engaged in the study due to the inertial thinking.

The traditional aerodynamic layout has been unchanged following the da vinci layout for 500 years, i.e. the front-to-back definition of the fuselage (or aircraft pilot) and the definition of the wing airfoil front-to-back edges have remained consistent. The conventional airfoil orientation is to define the large curvature change and relatively thick portion of the airfoil as the "leading edge"; the flat, relatively thin portion is defined as the "trailing edge". The fore-aft orientation of the fuselage or driver is defined as: the forward eye viewing orientation is defined as forward; the direction of the hindbrain scoop is defined as the rear; the streamline smooth part of the machine body is defined as a machine head, and the other end is a machine tail; the front and rear edges of the wing and the horizontal tail wing, the front and rear ends of the fuselage and the front and rear sides of the driver are placed in a consistent manner. Moreover, since the design of the airfoil always has a nose with a straight trailing edge, the upper airfoil surface has a nose and the lower airfoil surface has a straight trailing edge, resulting in a aerodynamic resultant force vector that is generally inclined toward the trailing edge, and the effect of a washdown in combination with a three-dimensional effect further increases the extent of the resultant force vector camber. The result of this aerodynamic layout orientation is that the projection of the aerodynamic resultant force vector in the horizontal velocity direction always points in the opposite direction to the flight velocity, creating "induced drag", resulting in a considerable total drag for the whole aircraft. In the flight process, the induced resistance sometimes accounts for a considerable part of the total resistance, and therefore, a large amount of fuel is consumed, a large amount of waste gas such as carbon dioxide is discharged, and the environment is polluted.

In summary, since aircraft were recently developed, the industry has been developing, without undue effort, for increasing lift and drag, increasing lift-drag ratio, and reducing weight per gram! So far, the design difficulty is getting larger and larger. Even if only a few percent of the efficiency is improved, a huge amount of engineering is required.

Disclosure of Invention

In view of this, the present invention aims to propose a new method for greatly improving the flight efficiency: the reverse pneumatic layout method changes the induced resistance into the induced thrust by the total pneumatic layout of the new design, thereby greatly reducing the pneumatic resistance and further increasing the lift-drag ratio.

The inventor is deeply researching the basic stone of modern fluid mechanics: following Bernoulli's principle, the existing aerodynamic layout of the leading and trailing edges of the conventional airfoils with respect to fuselage orientation was found to be not the best layout. There is a considerable efficiency difference if the layout of the wing is put against its way. Meanwhile, the existing knowledge of "induced resistance" was found to have a misregion, even a wrong knowledge.

The invention provides a mechanical overall aerodynamic layout method with a lifting surface moving in a fluid, comprising the following steps:

S1, deducing the relation between the load distribution, the aerodynamic force and the direction of the wing airfoil and the speed direction according to a Bernoulli formula, wherein the Bernoulli formula is as follows:

1/2*ρ*V ² +p _h +ρgh=constant (1)

In the formula (1), ρ is the fluid density, g is the gravitational acceleration, h is the height of the point, and the ρgh term can be omitted when the height is not changed greatlyV is the speed, p _h Is a local static pressure;

the present invention uses the aerodynamic generation principle of wing airfoils to analyze aerodynamic layout according to the Bernoulli principle and all basic assumptions deriving the Bernoulli equation, and illustrates the following 2 basic concepts.

Concept 1: the energy conservation is only related to the square of the speed and is not related to the direction of the speed vector;

concept 2: if all conditions are unchanged, including the geometric shape of the airfoil (relative thickness and camber at various points of the airfoil), the attack angle relative to the incoming flow, the incoming flow speed is unchanged, and only the direction of the incoming flow speed is changed by 180 degrees, the pressure distribution, the action point of the pneumatic resultant force, the magnitude of the resultant force and the orientation and the included angle of the resultant force vector relative to the chord line of the airfoil are unchanged.

From formula (1): for each point on the wing airfoil, dynamic pressure + static pressure = total pressure = constant, i.e.: the sum of kinetic energy and pressure energy is constant, which is determined by the law of conservation of energy;

From equation (1) it can be demonstrated that concept 1, whether velocity V is positive or negative (i.e. 180 degrees out of phase), the equation is true, the energy is scalar rather than vector, in classical mechanical systems there is only positive energy, no negative energy;

secondly, proving the concept 2, calculating the pressure coefficient of each point on the wing airfoil, wherein the pressure coefficient P refers to the ratio of the residual pressure (the difference between the local static pressure and the atmospheric pressure) to the flowing pressure far ahead, and the calculation formula is as follows:

P=P / (1/2*ρ _∞ *V _∞ ² )；

P= 1 - V ² /V _∞ ² ；

P= 1 - A ² _∞ /A ² ；

P= 1 - F ² (t,f)/F ² (t,f) _∞ （2）

in the formula (2), ρ _∞ And V _∞ The density and velocity of the fluid flowing far ahead;

a and A _∞ Is the flow tube cross-sectional area through which local and far forward flows;

f (t, F) and F (t, F) _∞ Is a function of the local and far forward shape of the fluid passing through the airfoil, including thickness t and camber f; since there is no airfoil far ahead, set F ² (t,f) _∞ For 1.0, the expression for P is derived as:

P= 1 - F ² (t,f)（3）

from formula (3): the pressure coefficient at each point on the wing airfoil is dependent only on the geometry at each point on the airfoil (airfoil local thickness and camber), independent of the direction of velocity; [ due to F ² (t, f) is a dimensionless quantity, not showing the velocity magnitude, in fact V has been included into the reference shorthand]。

From the above expression process of deriving the pressure coefficient P, the conclusion is:

The pressure coefficient at each point on the airfoil is dependent only on the geometry at each point on the airfoil (local airfoil thickness and camber) and is independent of the direction of velocity. (due to F ² (t, f) is a dimensionless quantity, not showing the velocity magnitude, and in fact V has been included into the reference shorthand).

From the above analysis, it follows that: the aerodynamic load distribution (magnitude and direction) on an airfoil, or wing, moving in a fluid is dependent only on the geometry of the airfoil, the magnitude of the velocity, and the direction of flight, so that the magnitude and orientation of the aerodynamic resultant force vector is constant relative to the airfoil or wing.

And/or solving a Navier-Stokes equation by utilizing CFD software, or obtaining the load distribution, the aerodynamic force and the direction of the wing airfoil by wind tunnel experiments and flight tests;

experiments are carried out on the concepts 1 and 2 through wind tunnel tests, blowing is carried out on a given wing section from the front, blowing is carried out on the wing section from the tail after the wing section rotates 180 degrees, and the change curves of the wing section lifting force and the wing section resistance along with the attack angle under the two conditions are measured and are basically the same.

The soviet union, also known from the literature, has once performed a 0-360 degree rotary blowing test on a certain airfoil, and discloses a set of experimental curves drawn manually, see fig. 3, limited to no computer data processing and computer aided drawing technique at the time, which are rough, possibly less accurate, but should be in acceptable error range, plus Su Lian a of reputation and credibility worldwide, which have important reference values, at least in terms of trend, without errors, and without errors exceeding 20% in accuracy. As can be seen from fig. 3: if the longitudinal axis is ranging from 0 degrees to 360 degrees, it is split into two segments: 0 degrees-180 degrees and 180 degrees-360 degrees. It is clear that the two graphs are very similar in terms of morphology, trend and magnitude. In particular, in the two subdivision ranges of 0-40 degrees and 180-220 degrees, the variation trend of the lift coefficient and the resistance coefficient along with the attack angle is quite similar, the values are quite similar, the resistance coefficient is better matched, the maximum lift coefficient is about 20% smaller in the rear blowing state than in the positive blowing state, and the influence of boundary layer generation and trailing edge separation caused by the viscosity of real gas is possible. However, this difference does not radically change the conclusion.

S2, reversely laying out the front and rear edges of the wing airfoil based on the load distribution, the aerodynamic resultant force and the relation between the direction and the speed direction of the wing airfoil obtained in the step S1, inverting the phase of the wing airfoil by 180 degrees, placing the rear edge of the wing airfoil in front of a machine body or a driver, leading the front edge of the wing airfoil to point to the rear of the machine body or the driver, and calculating zero lift resistance C of the whole machine _D0 Projection C of lift-induced force in the velocity direction _Di The method comprises the steps of carrying out a first treatment on the surface of the Converting components of aerodynamic force on a coordinate system among a machine body coordinate system, an airflow coordinate system and a ground coordinate system;

airfoil pressure profile, represented by vectors, with arrows outward representing suction; the arrows indicate positive pressure inwardly. R is the aerodynamic resultant force obtained by integrating the pressure along the airfoil surface. The resultant force R is the sum of all the pressure vectors on the airfoil. In general, the angle θ between R and the chord line of the airfoil is not always 90 degrees (chord line perpendicular), which is a function of three factors: the geometry of the airfoil, the chord line and the angle of attack of the incoming flow; in the three-dimensional case, θ is also related to the angle of under wash caused by wingtip vortices.

When the three-dimensional wing is considered, the wingtip vortex at the wingtip enables the airflow of the lower wing surface to return to the upper wing surface through the wingtip, so that the pressure difference between the upper wing surface and the lower wing surface is reduced, and the lift force of the wing is reduced. Meanwhile, the upward flow changes the flow direction of the upper airfoil surface air flow, generates the downward washing air flow and changes the direction of the incoming flow. The effect of the under wash is that the attack angle of the airfoil is reduced by the under wash angle, namely The projection component of the resultant force R on the chord line is increased by decreasing the inclination angle theta of the resultant aerodynamic force R on the airfoil to a direction more toward the trailing edge of the airfoil. The influence of three factors on the inclination of the resultant force vector azimuth should include three angles in combination: />，/>And->。

Table 1 below shows aerodynamic total force after three-dimensional wing wash-down effect versus wing chord angle of incidence θ versus angle of attack for low, medium and high Reynolds number wind tunnel experimental data (two-dimensional) and for medium aspect ratio wing design according to two wing profiles provided by university of Gettingen and NACA, U.S. GermanyIs a variation of (2). Wherein θ is the experimental data C of the wind tunnel _L And C _D (two-dimensional) calculation of lift-to-drag ratio k=c _L /C _D Then, θ=tan is calculated ^-1 K. The relationship between the mid-aspect ratio wing wash angle and the angle of attack is determined using the following equation:

。

table 1: the angle between the aerodynamic resultant force of two airfoils and the chord varies with the angle of attack

As can be seen from the data in table 1: the wind tunnel experimental data are aerodynamic lift, resistance and other experimental data obtained by data processing after the pressure is measured on the surface of the airfoil, and are converted into a dimensionless quantity C _L 、C _D， Typically expressed using a coordinate system attached to the airfoil. On board the aircraft is the machine body coordinate system, C _L And C _D Is the projection component of the aerodynamic force resultant force vector on the Y axis and the X axis of the machine body coordinate system. Known C _L And C _D The magnitude of the resultant force vector and its angle θ with the X-axis can be found in reverse. The angle θ does not include the angle of attackAnd air flow downward wash angle caused by three-dimensional effect. When aerodynamic force is used for flight mechanics calculation, conversion among a machine body coordinate system, an airflow coordinate system and a ground coordinate system is needed, and included angles between the machine body coordinate system and the airflow coordinate system are considered to comprise an attack angle +.>At the same time consider the angle of wash->The projected component of the aerodynamic force resultant force in the X direction of the airflow coordinate system is increased. It can also be seen from table 1 that: because of the airfoil front-to-back geometry asymmetry, even in the two-dimensional case, the aerodynamic resultant force is not perpendicular to the aerodynamic chord.

At small Reynolds numbers, the resultant force deviates far from the vertical line of the airfoil aerodynamic chord, at about 30-40 degrees.

Under the condition of large Reynolds number, when the attack angle is smaller, the resultant force is almost perpendicular to the aerodynamic chord, the projection in the X-axis direction is small, namely the resistance is small, the corresponding lift-drag ratio K is large, and the maximum value is reached.

In other cases, the aerodynamic force resultant force is always off vertical, leaning towards the airfoil trailing edge, causing considerable induced drag. The three-dimensional generation of wingtip vortices, which are washed down on the wing, further worsen the situation, see fig. 5.

The technical scheme of the invention clarifies the conceptual error area of resistance and induced resistance at the present stage. The resistance force means a force in a direction opposite to the forward motion velocity vector. Currently, aerodynamic drag is generally divided into two main categories, the first category refers to drag that is independent of lift, called zero-liter drag C _D0 The method comprises the steps of carrying out a first treatment on the surface of the The second type refers to the drag related to lift, called induced drag C _Di 。

The mathematical expression of the total resistance of the whole machine is: c (C) _D = C _D0 + C _Di ；

C _D0 This term is always opposite to the direction of motion, always positive, positive resistance. C (C) _Di The mechanism of this generation and C _D0 Quite differently, drag or thrust is defined with respect to the direction of movement velocity, and any external force that is consistent with the direction of movement of the aircraft that helps to accelerate the movement is called thrust or pull. Any external force that resists forward movement in the direction opposite to the direction of movement of the aircraft is called drag. On an aircraft, thrust or pull is provided by an engine or propeller mounted at the rear or front of the fuselage, which is always directed in front of the pilot or fuselage.

The present so-called "induced drag" recognizes that the projection of the force associated with lift in the horizontal direction must be opposite to the speed direction. This is essentially one-sided knowledge of the first place. Through detailed technical research, the accurate definition of the induction resistance is obtained as follows: the projected component of the aerodynamic force vector in the horizontal direction or close to the horizontal direction (usually the direction of the flight speed), or the horizontal projected component of the lift induced force, obtained by the pressure difference of the upper and lower wing surfaces generated on the wing profile by the bernoulli principle during the movement of the wing profile, is called "induced drag" if the projected component is directed opposite to the direction of the aircraft movement speed vector. Conversely, if the projected component is pointed at the same direction as the aircraft motion velocity vector, it is referred to as "induced thrust". This concept of subdivision induced forces will bring about a huge, revolutionary change in the future aerodynamic overall layout. The method is simple, and finding the correct direction is more important than finding a specific method. The idea of the invention is to make the harm more favorable. The induced resistance is changed into the induced thrust, so that the wing body azimuth consistency method in the traditional overall pneumatic layout is thoroughly changed, and the wing body azimuth inversion method is changed.

The conventional airfoil orientation is to define the large curvature change and relatively thick portion of the airfoil as the "leading edge"; the flat, relatively thin portion is defined as the "trailing edge". The fore-aft orientation of the fuselage or driver is defined as: the forward eye viewing orientation is defined as forward. The direction of the hindbrain scoop is defined as the posterior direction. The streamline smooth part of the machine body is defined as a machine head, and the other machine head is a machine tail. The existing overall aerodynamic layout azimuth is that the front and rear edges of wings and horizontal tail wing sections, the front and rear ends of a fuselage and the front and rear sides of a driver are placed consistently. This aerodynamic layout orientation creates "induced drag". Resulting in a considerable total drag for the whole machine, see fig. 4.

The new aerodynamic layout orientation of the present invention is primarily to reverse the layout of the leading and trailing edges of the wing so that the trailing edge of the wing or wing is placed in front of the fuselage or pilot with the leading edge of the wing pointing to the rear of the fuselage or pilot, i.e., the wing is inverted 180 degrees.

The wing profile phase-inverted by 180 degrees and the incidence angle of the wing profile relative to the airflow is ensured to be unchanged (or the installation angle is unchanged), and the position of the focus of the wing on the airframe is preferably kept at the original position; if the wing focus position has to be changed, the gravity center position of the whole machine and the position of the horizontal tail wing should be recalculated and laid out so as to ensure that the whole machine has reasonable static stability.

S3, calculating the lift-drag ratio K and the residual thrust coefficient n of the whole computer and other related parameters, wherein the calculation expressions of K and n are as follows:

K= C _L / C _D ；C _D = C _Do ±C _Di ；

is an error correction coefficient, and when the layout is forward, the plus sign is taken,/->Taking 1.0; in the reverse layout, take the minus sign +.>The value range of (2) is 0.8-0.95, and is reasonably selected according to the accuracy of the utilized data;

n = (σ- C _D0 /C _L - f *0.5) ±*1.05/(A*π)*C _L ；

σ= T/W ；

sigma is the thrust-weight ratio;the value method of (2) is the same as that of calculating K.

S4, calculating the flight performance, operability, stability and flight quality of the whole computer.

After aerodynamic layout of the wing-body reverse direction, the aerodynamic resultant force vector magnitude and the direction relative to the chord line of the wing are not changed under the same forward flying speed and the same attack angle condition because the geometrical shape of the wing is not changed. However, the projection component force direction of the resultant force in the speed direction is changed by 180 degrees, and the forward movement of the airplane is prevented, namely the forward movement of the airplane is assisted, namely the induced resistance is changed into the induced thrust, so that the total resistance of the airplane is greatly reduced, and the flight efficiency is greatly improved.

Further, the method of reverse layout of the leading and trailing edges of the wing airfoil of step S2 further comprises:

the airflow angle of attack or the mounting angle of the reverse layout wing airfoil is unchanged relative to the existing forward layout wing airfoil.

the position of the wing focus of the wing airfoil with the reverse layout on the aircraft body is the same as that of the existing wing airfoil with the forward layout, so that the complete aircraft has proper static stability.

Further, if the position of the wing focus of the reverse layout wing airfoil is changed, the position of the center of gravity of the whole aircraft (the center of gravity of the aircraft with the reverse layout wing is fully installed) and the position of the horizontal tail wing are recalculated and laid out. Ensuring proper static stability of the whole machine.

Further, the mechanical overall pneumatic layout method further comprises:

the boundary layer blowing lift-increasing technology is adopted to improve the airfoil lift.

Further, the method for calculating the lift-drag ratio K of the whole computer in the step S3 includes:

setting a correction coefficient of 1.0 or 0.8-0.95The horizontal projection component of the lift-induced force is corrected.

When the Bernoulli principle is utilized to deduce the conclusion that the wing profile load distribution, the aerodynamic force and the direction are irrelevant to the speed direction, classical mechanical assumptions such as continuous medium, non-viscosity, ideal fluid, incompressible fluid, steady flow, no heat exchange between the fluid and the outside, neglecting friction force and the like are adopted. While these assumptions are reasonable, do not change the nature of the Bernoulli principle per se, nor do they change the conclusions. But assuming that there is always a difference from the actual situation, there is an error. In practical application, a large amount of real data is needed to be obtained through wind tunnel test or free flight test, and the result calculated by the method is further corrected, improved and supplemented.

The reverse aerodynamic layout method can reduce aerodynamic efficiency due to the fact that the most important structural part (large relative thickness and large bending) of the airfoil profile for generating lift force is arranged behind the airfoil profile, and the structural part can be placed in the air flow which begins to or is separated from the rear part of the boundary layer, and the problem that the boundary layer is blown off by adopting a conventional boundary layer blowing technology can be solved. In the calculation, the horizontal projection component of the lift induction force is corrected.

After the reverse pneumatic layout method recommended by the invention is adopted, the maneuverability and stability of the whole machine are required to be paid attention. For designers and drivers that are accustomed to traditional layouts, there is a need to accommodate and to adapt to the definition of the control parameters that are completely reversed from before, given the new layout. These variations include:

the longitudinal parameters are inverted; the low head of the aircraft with the new layout can increase the attack angle, increase the lifting force and lift the aircraft. The original control lever is a pull rod airplane climbing, and the push rod airplane descends. Now (if the horizontal tail is installed without phase inversion, the elevator control lever definition is unchanged) becomes a push rod aircraft climbing and the pull rod aircraft descending. Attention to the angle of attackDoes not change the definition of (c): />Is the angle between the velocity vector line and the aerodynamic chord line. When the larger, thicker end of the airfoil (airfoil leading edge) is above the chord line and the velocity vector line is below +. >Is positive and vice versa.

To follow the original steering habit, this can be achieved by changing the polarity of the steering mechanism. Since the horizontal tail, and rudder generally employ symmetrical wing profiles, the conventional layout can be unchanged. However, if the original layout is kept unchanged, shifted or replaced, it should be noted that the polarity of the longitudinal, transverse and lateral control parameters changes in accordance with the corresponding coordination, if any, of the control surfaces (ailerons) or lifting surfaces (flaps) originally attached to the trailing edge of the wing. For autopilot aircraft or drones, it is easier to adapt to new layout characteristics by changing, tuning the polarity of the sensor or autopilot control signals.

In addition to the reduced drag, the reverse aerodynamic layout approach offers another advantage: when the traditional forward aerodynamic flow flows from the airfoil head to the trailing edge, the pressure distribution gradient on the airfoil is reverse pressure distribution along the flow direction, and the boundary layer formed by the viscosity of air is easy to separate and transition on the upper airfoil. The flow direction of the reverse pneumatic layout is opposite, and the pressure distribution gradient on the airfoil surface is positive pressure gradient distribution along the flow direction, so that the separation and transition of the airflow are delayed.

The wing-body reverse direction aerodynamic layout can be obtained by researching the influence of supersonic flight on the pressure distribution of the upper surface and the lower surface of the wing section, and is also suitable for supersonic aircraft design.

If shock waves are generated during supersonic flight, the pressure distribution on the surface of the airfoil (wing) is unchanged compared with subsonic speed, and only the upper airfoil is affected, as shown in fig. 6. In the strong shock regime, the pressure coefficient of the upper surface increases much, but this effect is concentrated at the trailing edge of the airfoil chord and at the middle of the airfoil, and the total aerodynamic load distribution is still concentrated at the front and middle of the airfoil. The air-lift type wind turbine is similar to subsonic conditions, and the weak shock wave state only has obvious influence on the middle part of the airfoil, so that the suction force of the upper airfoil surface is increased, and the total aerodynamic load is still similar to subsonic conditions and is concentrated at the front part of the airfoil. Wave drag is the projected component of the induced force in the velocity direction, and in conventional aerodynamic arrangements, is also added to the induced drag, indicating that the aerodynamic resultant is reclined, resulting in a substantial increase in the overall drag of the aircraft. The method changes the overall aerodynamic layout of the supersonic aircraft into the wing-body reverse layout, changes the induced resistance into the induced thrust, and mainly depends on the gradient theta of aerodynamic resultant force on the wing (airfoil) in a supersonic state relative to a chord line.

Unlike subsonic speeds, shock waves are always generated in the opposite direction of incoming flow of the wing profile (wing), the shock lines are inclined backwards, and pressure abrupt changes are generated after the shock lines, and the abrupt changes are related to the strength of the shock waves. The intensity of the shock wave is related to the geometry of the airfoil and the plane shape (sweepback angle) of the airfoil, in addition to the magnitude of the incoming flow velocity. In normal layout, if the airfoil head is round and blunt, strong shock waves (even positive shock waves) can be generated, the airfoil head is thinner, the tip is wedge-shaped, and weak shock waves can be generated. The airfoil is reversely arranged, and weak shock waves are usually formed when flying at supersonic speed because the airfoil tail is always thinner. In this case, the aerodynamic resultant force produced by the airfoil is substantially the same as the subsonic speed. The layout method of the present invention is therefore equally applicable to the overall aerodynamic layout of a supersonic aircraft.

The reverse layout method changes the lift induced resistance to the induced thrust, and the flight performance is greatly improved in the ground take-off stage and the cruise horizontal flight stage.

Take-off and running stage: as the total resistance of the aircraft is reduced, the residual thrust coefficient is increased, the running acceleration is increased and the running distance is shortened under the condition of unchanged stall speed. I.e. the requirements on the length of the runway are reduced. This is particularly advantageous for a carrier-based aircraft with a low aspect ratio wing that is to take off and land on the aircraft carrier deck. It is possible to dispense with the installation of expensive electromagnetic ejectors. The motion during the take-off phase of the aircraft is an unsteady motion that produces acceleration. Using newton's second law, the following equation can be listed:

F= m*a;m = W/g;F = T - Da - D _f ；

Wherein T is the engine takeoff thrust; da is aerodynamic resistance; d (D) _f The ground friction resistance is W, the total machine weight is W, and g is the gravitational acceleration.

Da = D ₀ ±D _i ；D _f Friction coefficient f=0.5 (average value) w=0.05;

according to the kinetic equation: 1/g dV/dt= (T/W-C) _D0 /C _L - f *0.5) ±C _Di /C _L ；

Wherein, define: thrust ratio σ=t/W; c (C) _Di /C _L = 1.05/(A*π)*C _L ；

Wherein C is _Di Is the dimensionless coefficient of the projection component of the induced force in the horizontal direction; c (C) _L Is that

The lift coefficient of the aircraft in the take-off stage is usually relatively large, and 2-3 are taken.

The above kinetic equation is a normal differential equation. Given initial conditions, the integration solution is performed.

To simplify the problem, the approximation assumes: the takeoff process is equal acceleration motion, and the dynamics equation is rewritten

The method comprises the following steps:

a = dV/dt = g*(σ- C _D0 /C _L - f *0.5) ±*1.05/(A*π)*C _L

a = n*g；

wherein n= (σ -C) _D0 /C _L - f *0.5) ±*1.05/(A*π)*C _L

a is acceleration, and n is residual thrust coefficient. The remaining thrust coefficients of the forward and reverse wing body layouts are different, resulting in a large difference in flight performance during the takeoff phase.

Solving the takeoff and running distance by using the equation:

ground clearance speed:C _L = 2~3；

running time t=v _ld /(n*g) ；

Running distance s=1/2×a×t ² Or s=v _ld* t。

Cruise plane flight stage: is steady movement and not accelerated. The engine only needs to provide thrust to overcome resistance to maintain cruising speed and maintain horizontal flight. The lift-drag ratio K is the main performance index at this stage. After the lift-drag ratio is calculated, the course, the endurance and the fuel consumption are not difficult to solve. To simplify the problem, the range is calculated using an approximation method, and does not have to be solved by an integration method. The results obtained are sufficiently accurate.

Lift-drag ratio k=c _L / C _D ；C _D = C _Do ±C _Di ；

And (3) navigation: l= (k×v)/Ce (W _F /W ₀ -0.5*W _F ) [ kilometers ]]

And (3) navigation time: h= (K)/Ce (W _F /W ₀ -0.5*W _F ) [ hour ]]

Both the residual thrust coefficient n and the lift-drag ratio K are closely related to the projection of the drag, particularly the lift-induced force, in the horizontal direction. After n and K are calculated for different pneumatic layouts, the corresponding flight performance can be calculated, and comparison is performed to display the advantages and disadvantages.

The invention also provides a computer readable storage medium having stored thereon a computer program which when executed by a processor carries out the steps of a method of mechanical overall aerodynamic layout with lifting surfaces moving in a fluid as described above.

The invention also provides a computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, which when executed implements the steps of the mechanical overall aerodynamic layout method with lifting surfaces moving in a fluid as described above.

Compared with the prior art, the invention has the beneficial effects that:

the invention relatively changes the direction of the projection component force of wing profile or wing induced force in the flying speed direction through reversely arranging the front and rear edge directions of wing profile, after aerodynamically arranging the wing-body reverse direction, the geometrical shape of the wing profile is not changed, the aerodynamic resultant force vector on the wing profile is not changed in size and direction relative to the chord line of the wing profile under the same flying speed and the same attack angle, but the direction of the projection component force of resultant force in the speed direction is changed by 180 degrees, thereby preventing the forward movement of the aircraft, changing the forward movement of the aircraft into helping the forward movement of the aircraft, namely changing the induced resistance into the induced thrust, thereby greatly reducing the total resistance of the aircraft and greatly improving the flying efficiency. In the case of a substantially constant lift, the lift-drag ratio increases substantially.

The reverse layout reduces the resistance, increases the residual thrust coefficient, shortens the take-off and running distance, shortens the runway and saves large land and good farmland. Is beneficial to keeping the area of 18 hundred million mu of cultivated land and producing enough grains. Is beneficial to the preparation of war and barren. Of course, the increase of the residual thrust coefficient n can save energy and reduce consumption, and is beneficial to green travel. Reducing environmental pollution. Reducing the carbon dioxide emission.

Because the range and the endurance of the aircraft are in direct proportion to the lift-drag ratio and the fuel consumption is in inverse proportion to the lift-drag ratio, the new pneumatic layout method increases the range, increases the speed and expands the flight envelope. Meanwhile, the energy is saved, and the fuel consumption is reduced. Reducing the emission of carbon dioxide and other harmful exhaust gases. Is beneficial to the protection of the earth environment and the coping with global climate change.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention.

In the drawings:

FIG. 1 is a schematic representation of the appearance (500 years ago) of a simulated bird fixed wing aircraft of the Davinci design;

FIG. 2 is a schematic diagram of a computer device according to an embodiment of the present invention;

FIG. 3 is a graph of an airfoil type rotary blowing experiment published by the center of the Soviet Union;

FIG. 4 is a pressure distribution diagram of a typical airfoil using vectorial representation;

FIG. 5 is a schematic illustration of the wash down angle caused by tip vortex of a three-dimensional airfoil and its effect on aerodynamic resultant force vector orientation;

FIG. 6 is a pressure profile of an airfoil in supersonic motion;

FIG. 7 is a diagram of two wing-body azimuth layouts of a generic aircraft having medium aspect ratio wings in accordance with an embodiment of the present invention;

FIG. 8 is a schematic diagram of a conventional unmanned aerial vehicle in accordance with an embodiment of the present invention;

FIG. 9 is a schematic diagram of a remote inspection and beating integrated large unmanned aerial vehicle in an embodiment of the invention;

FIG. 10 is a flow chart of a method for providing a mechanical overall aerodynamic layout with lifting surfaces moving in a fluid, in accordance with an embodiment of the present invention.

Detailed Description

Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, the same numbers in different drawings refer to the same or similar elements, unless otherwise indicated. The implementations described in the following exemplary examples are not representative of all implementations consistent with the present disclosure. Rather, they are merely examples of apparatus and products consistent with some aspects of the disclosure as detailed in the appended claims.

The terminology used in the present disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used in this disclosure and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any or all possible combinations of one or more of the associated listed items.

It should be understood that although the terms first, second, third, etc. may be used in this disclosure to describe various information, these information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present disclosure. The word "if" as used herein may be interpreted as "at … …" or "at … …" or "responsive to a determination", depending on the context.

Embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

Examples

1. Increased range design for a general purpose aircraft with medium aspect ratio wings:

Referring to fig. 7, a general aircraft has a total weight of 600 kg. Two persons are carried with luggage. The original flying performance is excellent. However, from Beijing, it does not fly to Guangzhou (1888.84 km). Further improvements in voyage are desired, enabling direct flight from Beijing to Guangzhou. After the reverse wing-body layout method provided by the invention is applied, the technical purpose is achieved.

The pneumatic layout of the machine is improved according to the requirements of users. After the wing-body position reverse position is adopted, the original static stability is maintained, and the balancing and stabilizing system is adjusted. The performance parameters of the machine are as follows:

length: 6.6 meters, maximum speed 222 km/h;

height: 2.3 meters, cruising speed 200 km/h;

wing: 8.6 meters, minimum speed 65 km/h, aspect ratio = 7.4;

wing area: 10 square meters, the duration is 6.7 hours, and the range is 1300 kilometers;

takeoff weight: 600 kg;

maximum power: 100. horsepower;

oil consumption, rise: 18.5/hour;

carrier oil: 130. lifting.

The original takeoff and running performance is as follows:

ground clearance speed:the method comprises the steps of carrying out a first treatment on the surface of the Taking C _L = 2.0，V _ld = 21.91 meters/second;

n =（σ- C _D0 /C _L - f *0.5) -*1.05/(A*π)*C _L ；

σ=T/W =0.415；C _D0 =0.025； f =0.05;=1.0，A =7.4；

n = 0.415 -0.0125 - 0.025 - 1.05/(3.1416*7.4)*2.0 = 0.378 - 0.045*2 = 0.378- 0.09 = 0.288；

running time t=v _ld /(n×g) = 21.91/(9.81×0.288) = 7.755 seconds;

Running distance s=1/2×a×t ² =170 meters.

The takeoff and running performance after reverse layout is as follows:

n=（σ- C _D0 /C _L - f *0.5) +*1.05/(A*π)*C _L = 0.378 + 0.9*0.045*2 = 0.378 +0.081= 0.459 ；

running time t=v _ld /(n×g) = 21.91/(9.81×0.459) =4.87 seconds;

running distance s=1/2×a×t ² =107 meters.

At a cruising altitude of 3000 meters, flying at 200 km/h. The zero liter drag coefficient is:

cd0=0.025; the induced drag coefficient is: c (C) _Di = 1.05/(3.1416*7.4)*C _L ²

K=0.045； C _L = 0.5； C _Di = 0.045*0.25= 0.01125；

Original all-machine drag coefficientLift-drag ratio k=13.89;

from this, the range l=1300 km and the fuel consumption 123.5L can be calculated.

The cruising performance after reverse layout is as follows:

cd0=0.025; the induced thrust coefficient is:；

K=0.043，C _L = 0.5；

improved resistance coefficient of the whole machine:；

lift-drag ratio k=35.7;

from this, the range l=3343 km and the fuel consumption 123.5L can be calculated.

Or, fly the same distance of 1300 km, only consume 48.1 liters of oil. Saving the oil by about 61 percent. Distance of flight

Is larger than the distance 1889 km from Beijing to Guangzhou, thereby achieving the design purpose.

2. Conventional unmanned aerial vehicle design:

external dimensions and basic performance: see fig. 8.

Span 3.73m;

average aerodynamic chord 0.373;

the length of the machine is 2.76m;

the maximum width of the machine body is 0.230m;

the maximum depth of the machine body is 0.260m;

The machine height is 0.740m;

the weight of the air machine is 16kg;

the fuel oil weight is 8.0kg;

payload: 5-8 kg;

maximum takeoff weight 35kg;

maximum flat flying speed 150km/h;

cruising speed 120km/h;

stall speed 60 km/h;

typical cruising altitude is 2000m;

theoretical rise limit 5000m;

the endurance time is more than or equal to 5 hours;

the control radius is 120km;

the wing of the unmanned aerial vehicle adopts the full-slit flap lift-increasing technology, and the wing profile is a high-lift supercritical wing profile with larger relative thickness. To further improve performance, the wing-body of the present invention is intended to be employed

Reverse orientation pneumatic layout technique, redesign. For this reason, the entire wing is "clean". Neither is provided with

Ailerons, and no flaps. The tail part adopts an inverted V-shaped tail fin for automatic control of the longitudinal direction and the transverse direction. Machine for making food

After the wings are reversely installed, the focus of the wings is maintained at the original configuration position. The magnitude and polarity of the installation angle are unchanged

Meets the new definition. The polarity of the control parameters of all channels, according to a new definition, by the flight control system

And the design is coordinated, so that the flight stability and good maneuverability of the unmanned aerial vehicle are ensured.

The advantages of the new layout configuration are exhibited by comparing the differences between the new configuration and the original configuration based on the aerodynamic profile using the originally calculated aerodynamic data.

Original flying performance:

zero lift resistance of the complete machine is cd0=0.0164, at 120 km/per cruise altitude of 2000 meters

The required lift coefficient for an hour of flight is cl=0.443;

inducing a resistance factor: k=0.032;

induction drag coefficient:

the resistance coefficient of the whole machine is as follows:lift-drag ratio k=19.52, duration 5 hours; the maximum range is 600 km; (control radius 120 km.)

Flying performance after reverse direction wing design:

The required lift coefficient for an hour of flight is cl=0.443, induced drag factor: k=0.032;；

lift-induced thrust coefficient:

the resistance of the whole machine is as follows:；

lift-drag ratio k=41.4, endurance time 10.62 hours; maximum range 1274 km. The basic performance is improved by more than 2 times.

3. Ultra-long-range reconnaissance and beating integrative unmanned aerial vehicle design:

this is an imaginary ultra-remote unmanned aerial vehicle employing a supercritical airfoil design, as shown in fig. 9. Has the function of integration of examination and beating. A high power turbofan engine is installed. The task load reaches 1.5 tons. May be a tactical nuclear weapon. The basic parameters are as follows:

28.5 m of wingspan, 12.5 m of full length, 4.2 m of height and 50 m of wing area ² ；

The aspect ratio is 24.0 (wing ends are provided with wing end standing vortex rise-increasing devices, and the equivalent aspect ratio is 48.0);

the average aerodynamic chord is 1.75 m, the take-off weight is 12305 kg, and the maximum thrust is 38.2 kilo-newtons;

the unit thrust fuel consumption rate is 0.543 kg/dyne.h; task load 1508 kg;

maximum height 19560 meters, stall speed 176 km/h, airfoil-QYX-5 (china, shi);

maximum speed 685 km/h, duration 40.5 hours, mission course 21000 km;

according to the parameters, firstly, calculating the aerodynamic data of the aircraft when flying at a cruising height of 19000 m at 685 m/h:

stall speed 176 km/h:

from the reynolds number and the wetted area, zero lift resistance relative to the wing reference area can be obtained, and after multiplying the correction error factor by 1.25, cd0=0.022. With these parameters, the flight performance of the two layout methods can be calculated separately and compared.

Takeoff and running performance of forward layout aircraft:

ground clearance speed:the method comprises the steps of carrying out a first treatment on the surface of the Taking C _L = 3，V _ld = 48.89 meters/second;

n =（σ- C _D0 /C _L - f *0.5) -*1.05/(A*π)*C _L ；

σ=T/W =0.297；C _D0 =0.022； f =0.05;=1.0，A =25；

n = 0.297 -0.018 - 0.025 - 1.05/(3.1416*25)*3 = 0.254 - 0.013*9 = 0.254 -0.117 = 0.137 ；

running time t=v _ld /(n×g) = 48.89/(9.81×0.137) = 36.38 seconds;

running distance s=1/2×a×t ² =1778 meters;

the takeoff and running performance after reverse layout is as follows:

n =（σ- C _D0 /C _L - f *0.5) +*1.05/(A*π)*C _L = 0.254 + 0.95*0.117= 0.254+0.111= 0.365；

running time: t=v _ld /(n×g) = 48.89/(9.81×0.365) =13.65 seconds;

distance of run: s=1/2 a t ² =668 meters;

cruise flat fly performance comparison:

(1) Normal wing-body azimuth coincidence layout: the resistance coefficient of the whole machine is as follows:

lift-drag ratio:

；

calculating the range l=19800 km under the layout;

(2) Reverse wing-body azimuth layout:

coefficient of induced thrust；

The resistance coefficient of the whole machine is；

Lift-drag ratio；

Calculate the range l= 46667 km (40024 km, also around the earth) under this layout

Far-! ) Any target anywhere on the earth may be hit.

The embodiment of the invention also provides a computer device, and fig. 2 is a schematic structural diagram of the computer device provided by the embodiment of the invention; referring to fig. 2 of the drawings, the computer apparatus includes: input means 23, output means 24, memory 22 and processor 21; the memory 22 is configured to store one or more programs; when executed by the one or more processors 21, cause the one or more processors 21 to implement a mechanical overall aerodynamic layout method with lifting surfaces moving in a fluid as provided by the above embodiments; wherein the input device 23, the output device 24, the memory 22 and the processor 21 may be connected by a bus or otherwise, for example in fig. 2 by a bus connection.

The memory 22 is used as a readable storage medium of a computing device and can be used for storing a software program and a computer executable program, and the program instructions corresponding to the mechanical overall pneumatic distribution method with the lifting surface moving in the fluid are provided; the memory 22 may mainly include a storage program area and a storage data area, wherein the storage program area may store an operating system, at least one application program required for functions; the storage data area may store data created according to the use of the device, etc.; in addition, memory 22 may include high-speed random access memory, and may also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other non-volatile solid-state storage device; in some examples, memory 22 may further comprise memory located remotely from processor 21, which may be connected to the device via a network. Examples of such networks include, but are not limited to, the internet, intranets, local area networks, mobile communication networks, and combinations thereof.

The input means 23 is operable to receive input numeric or character information and to generate key signal inputs relating to user settings and function control of the device; the output device 24 may include a display device such as a display screen.

The processor 21 performs the various functional applications of the device and the data processing, i.e. the implementation of the above-described method of mechanical overall aerodynamic layout with lifting surfaces moving in a fluid, by running software programs, instructions and modules stored in the memory 22.

The computer equipment provided by the embodiment can be used for executing the mechanical overall pneumatic layout method with the lifting surface moving in the fluid, and has corresponding functions and beneficial effects.

Embodiments of the present invention also provide a storage medium containing computer-executable instructions, which when executed by a computer processor, are for performing a mechanical overall aerodynamic layout method with lifting surfaces moving in a fluid as provided by the above embodiments, the storage medium being any of various types of memory devices or storage devices, the storage medium comprising: mounting media such as CD-ROM, floppy disk or tape devices; computer system memory or random access memory, such as DRAM, DDRRAM, SRAM, EDORAM, rambus (Rambus) RAM, etc.; nonvolatile memory such as flash memory, magnetic media (e.g., hard disk or optical storage); registers or other similar types of memory components, etc.; the storage medium may also include other types of memory or combinations thereof; in addition, the storage medium may be located in a first computer system in which the program is executed, or may be located in a second, different computer system, the second computer system being connected to the first computer system through a network (such as the internet); the second computer system may provide program instructions to the first computer for execution. Storage media includes two or more storage media that may reside in different locations (e.g., in different computer systems connected by a network). The storage medium may store program instructions (e.g., embodied as a computer program) executable by one or more processors.

Of course, the storage medium containing computer executable instructions provided by the embodiments of the present invention is not limited to the mechanical overall aerodynamic configuration method with lifting surface moving in fluid as described in the above embodiments, and may also perform the related operations in the mechanical overall aerodynamic configuration method with lifting surface moving in fluid provided by any of the embodiments of the present invention.

Thus far, the technical solution of the present invention has been described in connection with the preferred embodiments shown in the drawings, but it is easily understood by those skilled in the art that the scope of protection of the present invention is not limited to these specific embodiments. Equivalent modifications and substitutions for related technical features may be made by those skilled in the art without departing from the principles of the present invention, and such modifications and substitutions will be within the scope of the present invention.

The foregoing description is only of the preferred embodiments of the invention and is not intended to limit the invention; various modifications and variations of the present invention will be apparent to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method of mechanically gross aerodynamic placement with lifting surfaces moving in a fluid, comprising the steps of:

1/2ρ/>V ² + p _h +ρgh=constant (1)

In the formula (1), ρ is the fluid density, g is the gravitational acceleration, h is the height of the point, V is the speed, and p _h Is a local static pressure;

from formula (1): dynamic pressure + static pressure = total pressure = constant for each point on the wing airfoil;

the pressure coefficient of each point on the wing airfoil is calculated, wherein the pressure coefficient P refers to the ratio of the residual pressure to the flowing pressure far ahead, and the calculation formula is as follows:

P =P / (1/2/>ρ _∞ />V _∞ ² )；

P = 1 - V ² /V _∞ ² ；

P =1 - A ² _∞ / A ² ；

P = 1 - F ² (t,f)/F ² (t,f) _∞ （2）

P = 1 - F ² (t,f)（3）

from formula (3): the pressure coefficient of each point on the wing airfoil is related only to the geometry at each point on the airfoil, independent of the direction of velocity;

s3, calculating the lift-drag ratio K and the residual thrust coefficients n, wherein the calculation expressions of K and n are as follows:

K=C _L / C _D ；C _D = C _D0 ±C _Di ；

is an error correction coefficient, plus sign is given in forward layout>Taking 1.0; negative sign in reverse layout>The value range of (2) is 0.8-0.95, and the value is selected according to the accuracy of the utilized data;

n=(σ- C _D0 /C _L - f 0.5) ±/> 1.05/(A/>π)/>C _L ；

σ= T/W ；

sigma is the thrust-weight ratio;the value method of (2) is the same as the calculation of the K value;

s4, calculating the flight performance, operability, stability and flight quality of the whole computer;

The method of reverse layout of the leading and trailing edges of a wing airfoil of step S2 further comprises:

the airflow angle of attack or the installation angle of the wing airfoil of the reverse layout is unchanged relative to the existing wing airfoil of the forward layout;

the position of the wing focus of the wing airfoil of the reverse layout on the aircraft body is the same as the focus of the wing airfoil of the existing forward layout;

if the position of the wing focus of the wing airfoil of the reverse layout is changed, the gravity center position and the horizontal tail position of the whole machine are recalculated and laid out, so that the whole machine is ensured to have proper static stability.

2. The method of mechanical overall aerodynamic deployment with lifting surface motion in a fluid of claim 1, further comprising:

3. A computer-readable storage medium, on which a computer program is stored, characterized in that the program, when being executed by a processor, implements the steps of the mechanical overall aerodynamic layout method with lifting surfaces moving in a fluid according to claim 1 or 2.

4. A computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the processor implements the steps of the method for mechanical overall aerodynamic layout with lifting surface motion in a fluid according to claim 1 or 2 when the program is executed by the processor.