Rapid design method and system for propeller profile

Abstract

The application discloses a kind of propeller profile fast design method, including the working parameter of target aircraft to determine the design condition and design index of propeller;Select the profile airfoil of propeller and corresponding aerodynamic performance parameter;Propeller design space is constructed;Generate several sample points in design space;Aerodynamic performance data information of each sample point is obtained by using excitation disc method calculation;Proxy model of propeller sample library is constructed;Parameter optimization is carried out to the obtained proxy model to obtain the final parameter optimization result;According to parameter optimization result, the design of the propeller profile of target aircraft is completed.The application also discloses a kind of system for realizing the fast design method of the propeller profile.The application not only can realize the fast design of propeller profile, reliability and accuracy are better, and overall design efficiency is higher.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of aerospace, and particularly relates to a propeller profile rapid design method and system. BACKGROUND

[0002] With the development of economy and technology, aircrafts represented by unmanned aerial vehicles have been widely used in people's production and life, bringing endless convenience to people's production and life.

[0003] The propeller is an important component of the aircraft, which plays a decisive role in the flight performance of the aircraft. Therefore, the design of the propeller will directly affect the power efficiency, endurance and control performance of the aircraft. Therefore, the design of the propeller of the aircraft is of great significance to the aircraft.

[0004] At present, the traditional propeller profile design scheme still adopts the traditional modeling-computing scheme, that is, the preliminary scheme of the propeller profile is constructed through aerodynamics, and then the detailed mesh division, aerodynamics and fluid mechanics equation solving and simulation process are used to realize the design of the propeller profile. However, although this kind of design scheme can obtain a relatively accurate propeller profile, the calculation and simulation process is slow, and the design process and solving process are extremely cumbersome, and the design efficiency is poor. SUMMARY

[0005] One of the purposes of the present application is to provide a propeller profile rapid design method with high reliability, good accuracy and high efficiency.

[0006] The second purpose of the present application is to provide a system for realizing the propeller profile rapid design method.

[0007] The propeller profile rapid design method provided by the present application comprises the following steps:

[0008] S1. Obtain the working parameters of the target aircraft to determine the design working condition and design index of the propeller;

[0009] S2. Select the profile airfoil of the propeller and the corresponding aerodynamic performance parameters according to the data information determined in step S1;

[0010] S3. Construct the design space of the propeller according to the data information determined in step S2;

[0011] S4. Generate a plurality of sample points in the design space according to the design space constructed in step S3;

[0012] S5. Calculate the aerodynamic performance data information of each sample point by using the excitation disc method according to the sample points obtained in step S4;

[0013] S6. Constructing a proxy model of the propeller sample library according to the aerodynamic performance data information obtained in step S5;

[0014] S7. Performing parameter optimization on the proxy model obtained in step S6 based on an intelligent optimization algorithm to obtain a final parameter optimization result;

[0015] S8. Completing the design of the propeller profile of the target aircraft according to the parameter optimization result obtained in step S7.

[0016] The working parameters of the target aircraft are obtained in step S1 to determine the design working condition and design index of the propeller, and specifically include the following steps:

[0017] The working parameters and design requirements of the target aircraft are obtained, and task decomposition is performed to determine the design working condition and design index of the propeller;

[0018] The design working condition includes the flight Mach number, flight altitude and propeller speed of the target aircraft;

[0019] The design target includes maximum thrust, highest efficiency or highest efficiency under the condition of meeting the thrust, etc.

[0020] The profile airfoil and corresponding aerodynamic performance parameters of the propeller are selected according to the data information determined in step S1 in step S2, and specifically include the following steps:

[0021] Discretize the propeller surface from the root to the tip into a plurality of profile shapes along the radial direction;

[0022] Determine the airfoil of each profile shape;

[0023] Calculate the lift coefficient and drag coefficient of each profile shape at all possible angles of attack.

[0024] The design space of the propeller is constructed according to the data information determined in step S2 in step S3, and specifically includes the following steps:

[0025] According to the data information determined in step S2, the installation angle design range, chord length design range, propeller radius range and blade number range of each profile shape are determined to construct the design space of the propeller.

[0026] A plurality of sample points in the design space are generated according to the design space constructed in step S3 in step S4, and specifically include the following steps:

[0027] According to the design space constructed in step S3, the sample points in the design space are generated by using a design of experiment;

[0028] The test design includes a uniform design method and a Latin hypercube sampling method.

[0029] The step S5 calculates aerodynamic performance data information of each sample point by using the actuator disk method according to the sample point obtained in the step S4, and specifically includes the following steps.

[0030] The actuator disk method replaces the geometric details of the real blade with an equivalent momentum source term, and simplifies the three-dimensional unsteady N-S equation into a steady equation for solving;

[0031] The equivalent replacement of the propeller has an infinite number of blades, and is simplified into a non-thickness disc; based on the momentum theory, the body force is added as a source term into the momentum equation of the N-S equation, and then the steady flow field of the simplified shape is solved;

[0032] When the airflow flows through the section at the radius r of the disc surface, the force analysis is performed on the section at the radius r to obtain the changes of the corresponding aerodynamic parameters;

[0033] The lift dL of the section shape is calculated by using the following formula:

[0034]

[0035] In the formula, p is the flow density; W is the section flow velocity; C l is the section lift coefficient; c is the section chord length;

[0036] The drag dD of the section shape is calculated by using the following formula:

[0037]

[0038] In the formula, C d is the section drag coefficient;

[0039] The tension dT of the section shape is calculated by using the following formula:

[0040] dT = dLcosα i -dDsinα i

[0041] In the formula, α i is the airflow induced angle of attack;

[0042] The torque dQ of the section shape is calculated by using the following formula: dQ = r[dLsinα i +dDcosα i ];

[0043] The overall force of the propeller is calculated by integrating the entire disc, and the non-dimensional processing is performed to obtain the aerodynamic performance non-dimensional parameter of the propeller;

[0044] The non-dimensional parameters of the propeller aerodynamic performance include a drag coefficient C T , a torque coefficient C M , a power coefficient C P , and an efficiency P e , wherein:

[0045]

[0046] In the formula, T is the drag force generated by the propeller; p ∞ is the air density of the incoming flow; R is the radius of the propeller; W is the rotational angular velocity of the propeller; M is the torque generated by the propeller around the rotation axis; P is the power generated by the propeller; J is the advance ratio, and V ∞ is the advance speed.

[0047] The step S6 is to construct a proxy model of the propeller sample library according to the aerodynamic performance data information obtained in the step S5, and specifically includes the following steps:

[0048] According to the aerodynamic performance data information obtained in the step S5, the design parameters in the design space of the constructed propeller are taken as the input, and the aerodynamic performance data information is taken as the output, to construct a proxy model.

[0049] For each item of the aerodynamic performance data information, a proxy model is constructed.

[0050] The step S7 is to perform parameter optimization on the proxy model obtained in the step S6 based on an intelligent optimization algorithm to obtain a final parameter optimization result, and specifically includes the following steps:

[0051] The parameter optimization is performed on the proxy model obtained in the step S6 based on a cuckoo optimization algorithm to obtain the final parameter optimization result.

[0052] The step S8 is to complete the design of the propeller shape of the target aircraft according to the parameter optimization result obtained in the step S7, and specifically includes the following steps:

[0053] According to the parameter optimization result obtained in the step S7, the corresponding curve (usually composed of discrete points) of the profile shape is combined, and a computer-aided design software is used to construct the final curved surface shape of the blade of the propeller, to complete the design of the propeller shape of the target aircraft.

[0054] For radial each profile shape, the corresponding airfoil shape is scaled isometrically to meet the chord length requirement, and then rotated around the leading edge point by a set angle to meet the installation angle requirement; after the processing of all profile shapes is completed, the profile two-dimensional curve is connected into a blade three-dimensional surface meeting the set requirements by using surface lofting, and then the propeller main body is obtained by rotating symmetrically around the rotation axis according to the number of blades; finally, the hub shape is constructed, and the hub is connected to the blades according to the set requirements to obtain the final propeller shape.

[0055] The application further provides a system for realizing the rapid design method of the propeller shape, comprising an index determination module, a profile parameter determination module, a design space construction module, a sample point generation module, an aerodynamic data calculation module, an agent model construction module, a parameter optimization module and a shape generation module; the index determination module, the profile parameter determination module, the design space construction module, the sample point generation module, the aerodynamic data calculation module, the agent model construction module, the parameter optimization module and the shape generation module are sequentially connected; the index determination module is used to obtain the working parameters of the target aircraft to determine the design working condition and design index of the propeller, and upload the data information to the profile parameter determination module; the profile parameter determination module is used to select the profile airfoil and corresponding aerodynamic performance parameters of the propeller according to the received data information and the determined data information, and upload the data information to the design space construction module; the design space construction module is used to construct the design space of the propeller according to the received data information and the determined data information, and upload the data information to the sample point generation module; the sample point generation module is used to generate a plurality of sample points in the design space according to the received data information and the constructed design space, and upload the data information to the aerodynamic data calculation module; the aerodynamic data calculation module is used to calculate the aerodynamic performance data information of each sample point by using the actuator disk method according to the received data information and the obtained sample points, and upload the data information to the agent model construction module; the agent model construction module is used to construct the agent model of the propeller sample library according to the received data information and the obtained aerodynamic performance data information, and upload the data information to the parameter optimization module; the parameter optimization module is used to perform parameter optimization on the obtained agent model based on an intelligent optimization algorithm according to the received data information, to obtain the final parameter optimization result, and upload the data information to the shape generation module; and the shape generation module is used to complete the generation of the propeller shape of the target aircraft according to the received data information and the obtained parameter optimization result.

[0056] The propeller profile rapid design method and system provided by the application, by selecting the profile airfoil of the propeller and corresponding aerodynamic performance parameters in advance, constructing a design space and sample points, and using the excitation disc method to perform rapid and efficient calculation of the aerodynamic performance data of the sample points, and using an intelligent optimization algorithm to perform parameter optimization, the application can not only realize rapid design of the propeller profile, has good reliability and accuracy, and has higher overall design efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0057] Figure 1 The method flowchart of the method of the application.

[0058] Figure 2 The typical profile shape schematic diagram of the method of the application.

[0059] Figure 3 The typical profile design variable schematic diagram of the method of the application.

[0060] Figure 4 The blade radius and number schematic diagram of the method of the application.

[0061] Figure 5 The excitation disc schematic diagram of the method of the application.

[0062] Figure 6 The excitation disc calculation grid division schematic diagram of the method of the application.

[0063] Figure 7 The propeller profile force analysis schematic diagram of the method of the application.

[0064] Figure 8 The function module schematic diagram of the system of the application. DETAILED DESCRIPTION

[0065] As Figure 1 The method flowchart of the method of the application is shown: the propeller profile rapid design method disclosed by the application comprises the following steps:

[0066] S1. Obtain the working parameters of the target aircraft to determine the design working condition and design index of the propeller; specifically comprising the following steps:

[0067] Obtain the working parameters and design requirements of the target aircraft, perform task decomposition, and determine the design working condition and design index of the propeller;

[0068] The design conditions include the flight Mach number, flight altitude and propeller speed of the target aircraft, and the design conditions can be single or multiple conditions; for example, only the cruise design condition is considered, the cruise altitude is 5000 m, the cruise speed is 200 km / h, and the propeller speed is 3000 r / min; the design indicators are: thrust not less than 100 N, efficiency not less than 0.6, etc.;

[0069] The design targets include maximum thrust, maximum efficiency or maximum efficiency under the condition of meeting the thrust, etc.

[0070] S2. According to the data information determined in step S1, the profile airfoil of the propeller and the corresponding aerodynamic performance parameters are selected; specifically including the following steps:

[0071] Along the radial direction, the propeller surface is discretized into several profile shapes, i.e. airfoils, from the root to the tip;

[0072] Determine the airfoil of each profile shape; in specific implementation, relevant airfoils can be selected from existing airfoil libraries (typical airfoils such as CLARK-Y, as shown in Figure 2 According to the Mach number, Reynolds number, relative thickness of the airfoil, etc., select the appropriate airfoil; for different radial profile positions, the same airfoil or different airfoils can be selected; the selection of airfoil profile position is from 30% to 100% radius position (for example, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100% radius position) from the propeller shaft to the tip direction; calculate the aerodynamic performance of each profile airfoil under different conditions; for small and medium-sized aircraft, since the airfoil inflow velocity is not higher than 0.5 Mach, its aerodynamic force coefficient is basically not affected by the Mach number, and only the aerodynamic performance under different angles of attack needs to be calculated;

[0073] Calculate the lift coefficient and drag coefficient of each profile shape under all possible angles of attack; in specific implementation, for safety, 0°-360° full coverage can be selected; for low-speed airfoil aerodynamic performance, Xfoil, Profili and other tools can quickly realize the above process;

[0074] S3. According to the data information determined in step S2, the design space of the propeller is constructed; specifically including the following steps:

[0075] According to the data information determined in step S2, the installation angle design range, chord length design range, propeller radius range and blade number range of each profile shape are determined to construct the design space of the propeller;

[0076] In specific implementation, after the profile airfoil is determined, the curved shape of the blade is determined by the chord length and installation angle of each profile airfoil, as shown in Figure 3 Each profile contains two variables, chord length ci and installation angle a g,i , wherein i is 3-10, respectively corresponding to 30%, 40%, 50%, 60%, 70%, 80%, 90% and 100% of the radial position, as shown in Figure 4 ; Figure 4 , wherein 1 represents the hub position, 2 represents the radius size, 3 represents the 30% radial position, 4 represents the 40% radial position, 5 represents the 50% radial position, 6 represents the 60% radial position, 7 represents the 70% radial position, 8 represents the 80% radial position, 9 represents the 90% radial position, and 10 represents the 100% radial position; when the above selected radial positions are selected, there are 16 design parameters of the cross section, and the value range of each variable can be floated by a certain percentage above and below the initial value, for example, c i ∈[0.9c i0 ,1.1c i0 ] and a g,i ∈[0.9a g,i0 ,1.1a g,i0 ]; or, a numerical value can be floated on the basis of the initial value, for example, a g,i ∈[a g,i0 -5°,a g,i0 +5°]; in addition, the radius of the propeller and the number of blades of the propeller also need to be given; thus, the design variables are 16+2; finally, an optimal set of variables is determined as the final shape parameters, and the design of the propeller is completed; at the same time, if the design process is simple, the radius of the propeller and the number of blades of the propeller can be specified in advance, so that 1-2 design variables can be reduced;

[0077] S4. According to the design space constructed in step S3, a plurality of sample points in the design space are generated; specifically including the following steps:

[0078] According to the design space constructed in step S3, the sample points in the design space are generated by using the experimental design;

[0079] The construction of a more accurate mapping relationship by using a neural network model often requires a large number of samples, but the method of the present application is different, the proxy model constructed by the method of the present application is used to accelerate the optimization process, and thus only a small number of samples are required to construct the initial proxy model;

[0080] In specific implementation, the experimental design can adopt a uniform design method or a Latin hypercube sampling method, and the number of samples is about 10 times the number of variables;

[0081] Each sample point corresponds to a set of propeller shape parameters, and also corresponds to a propeller three-dimensional curved surface shape, which is used for subsequent aerodynamic performance calculation; at the same time, only sample point data is required in this step, and the propeller curved surface shape does not need to be constructed;

[0082] S5. According to the sample points obtained in step S4, the aerodynamic performance data information of each sample point is calculated by using the actuator disk method; specifically including the following steps:

[0083] The actuator disk method replaces the geometric details of the real blade with an equivalent momentum source term, and simplifies the three-dimensional unsteady N-S equation into a steady equation for solving;

[0084] The equivalent propeller has an infinite number of blades (as shown in Figure 5 ), and is simplified into a disc with no thickness; based on the momentum theory, the body force is added as a source term to the momentum equation of the N-S equation, and then the steady flow field of the simplified shape (as shown in Figure 6 ) is solved;

[0085] When the airflow flows through any point on the disc surface at a radius r, the force analysis is performed on the section at the radius r to obtain the changes of the corresponding aerodynamic parameters (as shown in Figure 7 );

[0086] The lift dL of the section shape is calculated by using the following formula:

[0087]

[0088] Wherein, p is the flow density; W is the section flow velocity; C l is the section lift coefficient; c is the section chord length;

[0089] The drag dD of the section shape is calculated by using the following formula:

[0090]

[0091] Wherein, C d is the section drag coefficient;

[0092] The tension dT of the section shape is calculated by using the following formula:

[0093] dT = dLcos a i -dDsin a i

[0094] Wherein, a i is the airflow induced angle of attack;

[0095] The torque dQ of the section shape is calculated by using the following formula: dQ = r [dLsin a i +dDcos a i ];

[0096] The overall force of the propeller is calculated by integrating the entire disc, and the non-dimensional processing is performed to obtain the aerodynamic performance non-dimensional parameter of the propeller;

[0097] The non-dimensional parameters of the propeller aerodynamic performance include the thrust coefficient C T , the torque coefficient C M , the power coefficient C P and the efficiency P e , wherein:

[0098]

[0099]

[0100] In the formula, T is the thrust generated by the propeller; p ∞ is the air density of the incoming flow; R is the radius of the propeller; Ω is the rotational angular velocity of the propeller; M is the torque generated by the propeller around the rotation axis; P is the power generated by the propeller; J is the advance ratio, and V ∞ is the advance speed;

[0101] The actuator disk method replaces the geometric details of the real blades with equivalent momentum source terms, simplifies the complex three-dimensional unsteady N-S equations into steady equations for solving, greatly shortens the period of CFD calculation, and greatly simplifies the difficulty of grid division and the workload brought by grid division. For example, in the unsteady calculation method, a complex three-dimensional grid needs to be independently generated for each propeller shape generated in the design process. When the actuator disk method is used, the blade profile details are ignored, and only one set of simple three-dimensional grid needs to be generated during the whole design process, and a propeller disk surface is specified. For different propeller shape parameters, only the installation angle, chord length, propeller radius and number of blades need to be changed;

[0102] The traditional method of solving unsteady N-S equations (UNS) or quasi-steady method in multiple reference frames (MRF method) needs to generate a separate complex spatial grid for different propeller shapes in the design process, and the generation process and calculation process are extremely complex and tedious. The method only needs to generate a relatively simple spatial grid during the whole design process. In order to adapt to propellers of different radii, it is ensured that the grid plane where the actuator disk is located has a large enough radius to cover the maximum radius requirement in the design space. When solving the flow field, only the elements in the specified radius propeller disk surface need to be marked to realize the flow field calculation of propellers of different radii. Compared with the UNS or MRF method, the workload of the method is reduced by more than 90% in both grid generation and flow field solving, thereby greatly improving the design efficiency;

[0103] S6. Constructing a proxy model of the propeller sample library according to the aerodynamic performance data information obtained in step S5; specifically including the following steps:

[0104] According to the aerodynamic performance data information obtained in step S5, taking the design parameters in the design space of the propeller constructed as input and taking the aerodynamic performance data information as output, a surrogate model is constructed; in specific implementation, there are many types of surrogate models, such as RBF neural network, Kriging model, etc., which can all be implemented;

[0105] The aerodynamic performance parameters are generally the pull force, torque, power, efficiency, etc. of the propeller, which are selected according to specific design requirements; for each item of aerodynamic performance data information, a surrogate model is constructed; in this way, the aerodynamic performance under any shape parameter in the design space can be quickly obtained, facilitating parameter optimization;

[0106] S7. Based on the intelligent optimization algorithm, the surrogate model obtained in step S6 is parameter-optimized to obtain the final parameter optimization result; the specific implementation includes the following steps:

[0107] The constructed surrogate model is replaced by the real CFD calculation result, and based on the cuckoo optimization algorithm, the surrogate model obtained in step S6 is parameter-optimized to obtain the final parameter optimization result;

[0108] In specific implementation, the cuckoo optimization algorithm includes the following steps:

[0109] 1. For a given objective function f(x), design variables x=(x1,...,x D ) T ;

[0110] 2. Generate an initial population of n host nests x i ;

[0111] 3. When t<Gen max (the number of iterations is less than the set maximum iteration threshold) or other set stop conditions are not met, the following steps 4-11 are looped:

[0112] 4. Randomly obtain a cuckoo or generate a solution through Levy flight;

[0113] 5. Evaluate the objective function value f i and the uniform constraint v i of the current obtained cuckoo or solution;

[0114] 6. Randomly select a nest (such as number j) from the n host nests;

[0115] 7. If x j is better than x i , then

[0116] 8. Replace solution i with new solution j;

[0117] 9. End;

[0118] 10 discard a portion (according to the probability p a discard) poor nests;

[0119] 11. build or generate a new nest or solution

[0120] 12. keep the best solution (or nest with good solutions);

[0121] 13. sort the solutions and find the best current solution;

[0122] 14. the number of iterations is increased by 1;

[0123] Meanwhile, the cuckoo optimization algorithm used in the method of the present application can also be replaced by other similar optimization algorithms, such as genetic algorithm, particle swarm optimization algorithm, etc.

[0124] S8. Complete the design of the propeller shape of the target aircraft according to the parameter optimization result obtained in step S7; specifically including the following steps:

[0125] According to the parameter optimization result obtained in step S7, combined with the curve corresponding to the profile shape (usually composed of discrete points), the final surface shape of the blade of the propeller is constructed by using computer-aided design software, and the design of the propeller shape of the target aircraft is completed;

[0126] For each radial profile shape, the corresponding airfoil shape is scaled by equal ratio to meet the chord length requirement, and then rotated around the leading edge point by a set angle to meet the installation angle requirement; after the processing of all profile shapes is completed, the profile two-dimensional curve is connected into a blade three-dimensional surface that meets the set requirements by using surface lofting, and then the rotational symmetry processing is performed according to the number of blades to obtain the propeller main body; finally, the hub shape is constructed, and the transition connection with the blades is performed according to the set requirements to obtain the final propeller shape.

[0127] The effect of the method of the present application is described below in combination with an embodiment:

[0128] Suppose that the cruise speed of the aircraft is 200 km / h, the cruise height is 3000 meters, the propeller inflow speed is 55.56 m / s, the atmospheric density is 0.909254 kg / m 3 , the given radius is 0.35 m, the number of blades is 2, the rotating speed is 4000 revolutions per minute (rpm), the profile shape is selected as NACA4412 airfoil, the installation angle and chord length of the 30% to 100% profile in the radial direction are selected as design variables, and there are a total of 16 variables. The design index is to maximize the propelling efficiency, and the pulling force is not less than 150 N.

[0129] The pulling force of the propeller obtained after the design of the present embodiment is 150.028 N, and the propelling efficiency P eis 0.526, and the profile installation angle and chord length are shown in Table 1:

[0130] Table 1 shows the geometric parameters of the designed propeller

[0131]

[0132] Meanwhile, the design method of the present application is adopted in the present embodiment, which takes about 300 core hours; if the existing design method is adopted, it takes more than 10000 core hours; and the difference between the results obtained by the present method and the existing method is about 3%. It can be seen that the design method of the present application is faster, more efficient, and also has better accuracy and reliability.

[0133] As Figure 8 The functional module schematic diagram of the system of the present application is shown in the figure: the system for realizing the fast design method of the propeller profile disclosed in the present application comprises an index determination module, a profile parameter determination module, a design space construction module, a sample point generation module, an aerodynamic data calculation module, an agent model construction module, a parameter optimization module and a profile generation module; the index determination module, the profile parameter determination module, the design space construction module, the sample point generation module, the aerodynamic data calculation module, the agent model construction module, the parameter optimization module and the profile generation module are sequentially connected; the index determination module is used to obtain the working parameters of the target aircraft to determine the design working condition and design index of the propeller, and upload the data information to the profile parameter determination module; the profile parameter determination module is used to select the profile airfoil of the propeller and the corresponding aerodynamic performance parameters according to the received data information and the determined data information, and upload the data information to the design space construction module; the design space construction module is used to construct the design space of the propeller according to the received data information and the determined data information, and upload the data information to the sample point generation module; the sample point generation module is used to generate a plurality of sample points in the design space according to the received data information and the constructed design space, and upload the data information to the aerodynamic data calculation module; the aerodynamic data calculation module is used to calculate the aerodynamic performance data information of each sample point by using the actuator disc method according to the received data information and the obtained sample points, and upload the data information to the agent model construction module; the agent model construction module is used to construct the agent model of the propeller sample library according to the received data information and the obtained aerodynamic performance data information, and upload the data information to the parameter optimization module; the parameter optimization module is used to perform parameter optimization on the obtained agent model based on an intelligent optimization algorithm according to the received data information, to obtain the final parameter optimization result, and upload the data information to the profile generation module; the profile generation module is used to complete the generation of the propeller profile of the target aircraft according to the received data information and the obtained parameter optimization result.

Claims

1. A rapid design method for propeller shape, comprising the following steps: S1. Obtain the operating parameters of the target aircraft to determine the design conditions and design specifications of the propeller; S2. Based on the data information determined in step S1, select the propeller airfoil profile and corresponding aerodynamic performance parameters; S3. Based on the data information determined in step S2, construct the design space for the propeller; S4. Based on the design space constructed in step S3, generate several sample points within the design space; S5. Based on the sample points obtained in step S4, the aerodynamic performance data of each sample point is calculated using the excitation disk method; specifically, the following steps are included: The excitation disk method replaces the geometric details of the real blade with the equivalent momentum source term, simplifying the three-dimensional unsteady Navier-Stokes equations into steady equations for solution; The equivalent propeller has an infinite number of blades and is simplified to a disk with no thickness. Based on momentum theory, the volume force is added as a source term to the momentum equation of the Navier-Stokes equations, and then the steady flow field of the simplified shape is solved. When the airflow passes through any point at radius r on the disk surface, the force analysis is performed on the profile at radius r to obtain the changes in the corresponding aerodynamic parameters; The lift force on the cross-sectional shape is calculated using the following formula. : In the formula The incoming flow density; The inflow velocity is the cross-sectional velocity. The lift coefficient is the cross-sectional lift coefficient. The chord length of the cross section; The drag force on the cross-sectional shape is calculated using the following formula. : In the formula This is the section drag coefficient; The tensile force on the cross-sectional shape is calculated using the following formula. : In the formula Angle of attack induced by airflow; The torque on the cross-sectional shape was calculated. for ; The overall force on the propeller is obtained by integral calculation over the entire disk, and then the force is processed without quantization to obtain dimensionless parameters of the propeller's aerodynamic performance. Dimensionless parameters of propeller aerodynamic performance include thrust coefficient Torque coefficient Power coefficient and efficiency ,in: In the formula The thrust generated by the propeller; The density of the incoming airflow; The radius of the propeller; ω is the angular velocity of the propeller. The torque generated by the propeller around its axis of rotation; The power generated by the propeller; For the forward ratio, and , Forward speed; S6. Based on the aerodynamic performance data obtained in step S5, construct a proxy model for the propeller sample library; S7. Based on the intelligent optimization algorithm, perform parameter optimization on the surrogate model obtained in step S6 to obtain the final parameter optimization result; S8. Based on the parameter optimization results obtained in step S7, complete the design of the propeller shape of the target aircraft.

2. The rapid design method for propeller shape according to claim 1, characterized in that... Step S1, which involves obtaining the operating parameters of the target aircraft to determine the design conditions and design specifications of the propeller, specifically includes the following steps: Obtain the target aircraft's operating parameters and design requirements, and decompose the task to determine the propeller's design conditions and design specifications. The design conditions include the target aircraft's Mach number, flight altitude, and propeller speed; The design parameters include maximum thrust, highest efficiency, or highest efficiency while meeting the thrust requirements.

3. The rapid design method for propeller shape according to claim 2, characterized in that... Step S2, which involves selecting the propeller's airfoil profile and corresponding aerodynamic performance parameters based on the data information determined in step S1, specifically includes the following steps: Along the radial direction, the propeller surface is discretized from the root to the tip into several cross-sectional shapes; Determine the airfoil shape for each cross section; The lift coefficient and drag coefficient of each profile shape at all possible angles of attack were calculated.

4. The rapid design method for propeller shape according to claim 3, characterized in that... Step S3, which involves constructing the propeller design space based on the data information determined in step S2, specifically includes the following steps: Based on the data information determined in step S2, the design range of the installation angle, the design range of the chord length, the range of the propeller radius, and the range of the number of blades for each cross-sectional shape are determined to construct the design space of the propeller.

5. The rapid design method for propeller shape according to claim 4, characterized in that... Step S4, which involves generating several sample points within the design space constructed in step S3, specifically includes the following steps: Based on the design space constructed in step S3, experimental design is used to generate sample points within the design space; The experimental design includes uniform design and Latin hypercube sampling.

6. The rapid design method for propeller shape according to claim 5, characterized in that... Step S6, which involves constructing a proxy model for the propeller sample library based on the aerodynamic performance data obtained in step S5, specifically includes the following steps: Based on the aerodynamic performance data obtained in step S5, a proxy model is constructed using the design parameters in the constructed propeller design space as input and the aerodynamic performance data as output. For each piece of startup performance data, a proxy model is constructed.

7. The rapid design method for propeller shape according to claim 6, characterized in that... Step S7, based on an intelligent optimization algorithm, optimizes the parameters of the surrogate model obtained in step S6 to obtain the final parameter optimization result. Specifically, this includes the following steps: Based on the Cuckoo Optimization Algorithm, the parameters of the surrogate model obtained in step S6 are optimized to obtain the final parameter optimization result.

8. The rapid design method for propeller shape according to claim 7, characterized in that... Step S8, which involves designing the propeller shape of the target aircraft based on the parameter optimization results obtained in step S7, specifically includes the following steps: Based on the parameter optimization results obtained in step S7, and combined with the curve corresponding to the profile shape, computer-aided design software is used to construct the final surface shape of the propeller blades, thus completing the design of the propeller shape of the target aircraft. For each radial section shape, the corresponding airfoil shape is scaled proportionally to meet the chord length requirement, and then rotated around the leading edge point by a set angle to meet the installation angle requirement. After processing all the cross-sectional shapes, surface lofting is used to connect the two-dimensional curves of the cross-section into a three-dimensional surface of the blade that meets the set requirements. Then, rotational symmetry is performed around the rotation axis according to the number of blades to obtain the propeller body. Finally, the shape of the hub is constructed and transitionally connected to the blades according to the set requirements to obtain the final propeller shape.

9. A system for implementing a rapid design method for the propeller shape according to any one of claims 1 to 8, characterized in that... It includes a specification determination module, a profile parameter determination module, a design space construction module, a sample point generation module, an aerodynamic data calculation module, a surrogate model construction module, a parameter optimization module, and an shape generation module; these modules are connected in series. The specification determination module is used to obtain the working parameters of the target aircraft to determine the design conditions and design specifications of the propeller, and then uploads the data information to the profile parameter determination module. The profile parameter determination module is used to select the propeller's airfoil and corresponding aerodynamic performance parameters based on the received and determined data information, and then upload the data information to the design space construction module. The design space construction module is used to construct the propeller design space based on the received and determined data information, and upload the data information to the sample point generation module. The sample point generation module generates several sample points within the design space based on the received data and the constructed design space, and uploads the data to the aerodynamic data calculation module. The aerodynamic data calculation module calculates the aerodynamic performance data of each sample point using the excitation disk method based on the received data and the obtained sample points, and uploads the data to the proxy model construction module. The proxy model construction module constructs a proxy model for the propeller sample library based on the received data and the obtained aerodynamic performance data, and uploads the data to the parameter optimization module. The parameter optimization module is used to optimize the parameters of the obtained proxy model based on the received data information and intelligent optimization algorithm, so as to obtain the final parameter optimization result and upload the data information to the shape generation module. The shape generation module is used to generate the propeller shape of the target aircraft based on the received data and the optimized parameters.

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