A layout method for steady-state temperature distortion inlet temperature test

Abstract

The present application provides a method for testing the layout of an inlet temperature of a steady-state temperature distortion test, which belongs to the field of aero-engine testing. The method comprises: S10, constructing a mathematical model of the temperature field of the measurement section in the steady-state temperature distortion test and a mathematical model of the test layout for temperature measurement using a fixed total temperature probe; S20, determining the temperature field parameters used to describe the temperature field distortion characteristics, calculating the relative error sum of the temperature field parameters under the prior flow field and the temperature field parameters at the corresponding coordinates of the test layout, thereby determining the optimization target of the test layout; S30, using the circumferential angle of the fixed total temperature probe in the test layout as the optimization parameter and the relative error sum of the temperature field parameters as the optimization target, and using an optimization algorithm to optimize the circumferential angle of the fixed total temperature probe in the test layout, thereby obtaining the circumferential optimal angle of fixed total temperature probes with different circumferential numbers in the steady-state temperature distortion test. The method of the present application has good convergence and high calculation accuracy.

Description

Technical Field

[0001] The present application belongs to the field of aero-engine testing, and in particular relates to a steady-state temperature distortion inlet temperature test layout method. Background Art

[0002] Inlet temperature distortion is a destabilizing factor affecting aircraft engine aerodynamic stability and plays a decisive role. Temperature distortion at the engine inlet effectively alters the temporal and spatial distribution of airflow density, either locally or globally, thereby affecting the engine's stable operation. In engineering, temperature distortion tests are primarily used to verify an aircraft engine's resistance to temperature distortion. Temperature distortion tests can be divided into steady-state and transient temperature distortion tests based on their time characteristics. Together, these tests describe an aircraft engine's resistance to temperature distortion.

[0003] Steady-state temperature distortion testing requires a temperature measurement system to efficiently and accurately measure the compressor inlet temperature field in aircraft engines. Traditional temperature distortion testing typically uses a rotating rake to measure the temperature field, but this method requires modification of the aircraft engine inlet, including the installation of a rotating mechanism and sealing structure. This results in lengthy test preparation and high construction costs. Summary of the Invention

[0004] The purpose of this application is to provide a steady-state temperature distortion inlet temperature test layout method to solve or alleviate at least one problem in the background technology.

[0005] The technical solution of this application is: a steady-state temperature distortion inlet temperature test layout method, comprising:

[0006] S10, constructing a mathematical model of the temperature field of the measurement section in the steady-state temperature distortion test and a mathematical model of the test layout for temperature measurement using a fixed total temperature probe;

[0007] S20, determining temperature field parameters for describing temperature field distortion characteristics, calculating the sum of relative errors between the temperature field parameters under the prior flow field and the temperature field parameters at corresponding coordinates of the test layout, thereby determining an optimization target for the test layout;

[0008] S30, taking the circumferential angle of the fixed total temperature probe in the test layout as the optimization parameter and the relative error sum of the temperature field parameters as the optimization target, an optimization algorithm is used to optimize the circumferential angle of the fixed total temperature probe in the test layout, thereby obtaining the optimal circumferential angle of fixed total temperature probes with different circumferential numbers in the steady-state temperature distortion test.

[0009] Preferably, the mathematical model of the temperature field of the measurement section is:

[0010] ;

[0011] in, T is the total temperature field function of the measured cross section, r 、 i are the radius and angle in polar coordinate system, f i ( r , i ) represents the spatial position ( r , i ), the subscript i represents the sector in the heating state, where i=1,2,...,N corresponds to sector 1, sectors 1 to 2, sectors 1 to 3 to sectors 1-N, respectively, and N is a natural number.

[0012] Preferably, the mathematical model of the test layout for temperature measurement using a fixed total temperature probe is:

[0013] ;

[0014] in, T p Indicates the p The measured temperature of each sensing part, ( r j , i k ) represents the spatial position of the receptive part in polar coordinates, j 、 k Respectively represent the radial and circumferential positions of the sensing part.

[0015] Preferably, the process of determining the temperature field parameters for describing the temperature field distortion characteristics includes:

[0016] According to the average temperature of the measuring section T F,av , average temperature in high temperature zone T θ + av And the circumferential angle distribution of high temperature area and the known incoming flow temperature T 0 , calculate the temperature distortion index, which includes the average relative temperature rise δ T 2 , circumferential non-uniformity of temperature field and circumferential dimensions of high temperature zone i + :

[0017] ;

[0018] By analyzing the calculation expression of the temperature distortion index, it is obtained that the average relative temperature rise of the surface δ T 2Source flow temperature T 0 and the average temperature of the measuring section T F,av Determine the circumferential nonuniformity of the temperature field The average temperature of the measuring section T F,av and the average temperature of the high temperature zone T θ + av Decide;

[0019] According to the calculation expression of temperature distortion index, the average temperature of the measurement section is determined. T F,av , average temperature in high temperature zone T θ + av and circumferential dimensions of high temperature zone i + Three temperature field parameters are used to describe the temperature field distortion characteristics.

[0020] Preferably, the process of calculating the relative error sum of the temperature field parameters under the prior flow field and the temperature field parameters at the corresponding coordinates of the test layout, thereby determining the optimization target of the test layout includes:

[0021] The average temperature of the measurement section under the prior flow field is calculated by extracting the temperature field of the measurement section under the heating state of each sector of the compressor in the prior flow field. (T F,av ) real , average temperature in high temperature zone (T θ + av ) real and circumferential dimensions of high temperature zone (i + ) real By obtaining the temperature at the corresponding measuring point coordinates of the test layout, the average temperature of the measuring section under the test layout is calculated. (T F,av ) test , average temperature in high temperature zone (T θ + av ) test and circumferential dimensions of high temperature zone (i + ) test ;

[0022] The relative measurement error caused by the position of the measuring point in the test layout is obtained based on the temperature field parameters under the prior flow field and the temperature field parameters at the corresponding coordinates of the test layout:

[0023] ;

[0024] The relative error and error are: error=error 1 +error 2 +error 3 , where error1 is the relative error of the average temperature of the measured section, error2 is the relative error of the average temperature in the high temperature zone, and error3 is the relative error of the circumferential dimension in the high temperature zone.

[0025] Preferably, a particle swarm optimization algorithm is used to optimize the circumferential angle of the fixed total temperature probe in the test layout, and the process includes:

[0026] First, a group of particles is initialized in the solution space. Each particle represents a potential optimal solution to the extreme value optimization problem. The particle characteristics are characterized by three indicators: the particle position, which represents the circumferential angle of the fixed total temperature probe in the test layout; the particle velocity, which represents the change in the circumferential angle of the fixed total temperature probe in the test layout; and the particle fitness, which represents the relative error of the temperature field parameters.

[0027] Particles move in the solution space, and the particle position and particle velocity are updated by tracking individual extreme values ​​and group extreme values. The fitness value is calculated every time the particle is updated, and the individual extreme value and group extreme value are updated by comparing the fitness value of the new particle. When the fitness value of the new particle is less than the optimization target, the optimal particle position, particle velocity and particle fitness are obtained, thereby obtaining the optimal temperature field parameters.

[0028] The steady-state temperature distortion inlet temperature test layout method of the present application has good convergence and high calculation accuracy, and can quickly carry out temperature distortion test measurements. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions provided by this application, the following is a brief introduction to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of this application.

[0030] Figure 1 This is a schematic diagram of the steady-state temperature distortion inlet temperature test layout method of this application.

[0031] Figure 2 Schematic diagram of the influence of group size on relative error sum according to an embodiment of the present application.

[0032] Figure 3This is a temperature field parameter distribution diagram for different numbers of circumferential measuring points according to an embodiment of the present application.

[0033] Figure 4 Schematic diagram of temperature distribution of simulated measurement results of heating states in different sectors according to an embodiment of the present application. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the implementation of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below in conjunction with the drawings in the embodiments of this application.

[0035] In the development of aircraft engines and aero-derivative combustion engines, fixed total temperature or total pressure probes are often used to measure the inlet flow field. Compared to rotating rakes, fixed total temperature probes not only effectively reduce time and money costs, but can also be integrated into general aircraft engine development testing. Therefore, this application proposes a steady-state temperature distortion inlet temperature test layout method. Using a fixed total temperature probe, this method achieves efficient, low-cost, and high-precision distortion temperature testing.

[0036] like Figure 1 As shown, the steady-state temperature distortion inlet temperature test layout method provided by this application includes the following process:

[0037] S10, constructing a mathematical model of the temperature field of the measurement section in the steady-state temperature distortion test and a mathematical model of the test layout for temperature measurement using a fixed total temperature probe.

[0038] In this application, a steady-state temperature distortion test is implemented based on a steady-state temperature distortion generator. The simulated flow field of the steady-state temperature distortion generator is used as the prior flow field to carry out the design of the test layout for the steady-state temperature distortion test. In the simulated flow field of the steady-state temperature distortion generator, the temperature field of the measurement section can be expressed as:

[0039] ;

[0040] in, T is the total temperature field function of the measured cross section, r 、 i are the radius and angle in polar coordinate system, f i ( r , i ) represents the spatial position of sector i under heating state ( r , i), where the subscript i represents the sector in the heating state, where i=1, 2, ..., N correspond to sector 1, sectors 1 to 2, sectors 1 to 3, and 1-N, respectively, and N is a natural number. Typically, the number of sectors in a steady-state temperature distortion generator can be set to 6, 8, or 10, with N generally being half the number of sectors.

[0041] The fixed total temperature probe used for temperature measurement in this application is typically a thermocouple probe, with multiple sensing elements (i.e., measuring points) arranged radially. This allows for simultaneous measurement of multiple sensing elements along the radial direction. The number of radially arranged sensing elements is determined based on the testing capabilities of the fixed total temperature probe, and the radial positions of the sensing elements are determined using the equal annular surface method. The radial positions of the sensing elements are input as fixed values.

[0042] The measured temperature of the sensing part of the fixed total temperature probe is the test layout of the fixed total temperature probe. The mathematical model of the test layout can be expressed as:

[0043] ;

[0044] in, T p Indicates the p The measured temperature of each sensing part, ( r j , i k ) represents the spatial position of the receptive part in polar coordinates, j 、 k Represent the radial and circumferential positions of the sensing part respectively.

[0045] S20, determining temperature field parameters for describing temperature field distortion characteristics, calculating the relative error sum between the temperature field parameters under the prior flow field and the temperature field parameters at corresponding coordinates of the test layout, thereby determining an optimization target for the test layout.

[0046] According to the average temperature of the measuring section T F,av , average temperature in high temperature zone T θ + av And the circumferential angle distribution of high temperature area And the incoming flow temperature is known T 0 , the temperature distortion index can be calculated - that is, the average relative temperature rise δ T 2 , circumferential non-uniformity of temperature field and circumferential dimensions of high temperature zone i + :

[0047] .

[0048] From the calculation expression of temperature distortion index, we can get the average relative temperature rise of the surface δ T 2 Source flow temperature T 0 and the average temperature of the measuring section T F,av Determine the circumferential nonuniformity of the temperature field The average temperature of the measuring section T F,av and the average temperature of the high temperature zone T θ + av Therefore, in this application, the average temperature of the cross section is measured T F,av , average temperature in high temperature zone T θ + av and circumferential dimensions of high temperature zone i + Three more intuitive temperature field parameters further simplify the description of temperature field distortion characteristics.

[0049] By extracting the temperature field of the measurement section under the heating state of each sector of the compressor in the prior flow field, the average temperature of the measurement section under the prior flow field can be calculated. (T F,av ) real , average temperature in high temperature zone (T θ + av ) real and circumferential dimensions of high temperature zone (i + ) real ; By obtaining the temperature at the corresponding measuring point coordinates under the test layout, the average temperature of the measuring section under the test layout can be calculated (T F,av ) test , average temperature in high temperature zone (T θ + av ) test and circumferential dimensions of high temperature zone (i + ) test .

[0050] Combining the temperature field parameters under the prior flow field with the calculated temperature field parameters at the corresponding coordinates of the test layout, the relative error of the fixed total temperature probe in the test layout due to the measurement point position error can be obtained:

[0051] ;

[0052] The relative error sum is: error=error 1 +error 2 +error 3 ， Where error1 is the relative error of the average temperature of the measured section, error2 is the relative error of the average temperature in the high temperature zone, and error3 is the relative error of the circumferential dimension in the high temperature zone.

[0053] The relative error sum is the optimization target of the objective function. The smaller the value of the objective function is, the more accurate the calculation result of the test layout is.

[0054] S30, taking the circumferential angle of the fixed total temperature probe in the test layout as the optimization parameter and the relative error sum of the temperature field parameters as the optimization target, an optimization algorithm is used to optimize the circumferential angle of the fixed total temperature probe in the test layout, thereby obtaining the optimal circumferential angle of fixed total temperature probes with different circumferential numbers in the steady-state temperature distortion test.

[0055] In this application, the PSO (Particle Swarm Optimization) algorithm is used as the optimization algorithm. First, a group of particles are initialized in the solution space. Each particle represents a potential optimal solution to the extreme value optimization problem. The particle characteristics are represented by three indicators: the particle position representing the circumferential angle of the fixed total temperature probe in the test layout, the particle velocity representing the change in the circumferential angle of the fixed total temperature probe in the test layout, and the particle fitness representing the relative error of the temperature field parameters. Among them, the fitness value is calculated by the fitness function, and the quality of its value indicates the quality of the particle. The individual extreme value refers to the optimal fitness position calculated from the position experienced by the individual, representing the circumferential angle (vector) of the fixed total temperature probe in the optimal test layout; the group extreme value refers to the optimal fitness position searched by all particles in the population, representing the circumferential angle (vector group) of the fixed total temperature probe in multiple optimal test layouts. Particles move in the solution space, and the particle position and particle velocity are updated by tracking individual extreme values ​​and group extreme values. The fitness value is calculated every time the particle is updated, and the individual extreme value and group extreme value are updated by comparing the fitness value of the new particle. When the fitness value of the new particle is less than the optimization target, the optimal particle position, particle velocity and particle fitness are obtained, thereby obtaining the optimal temperature field parameters.

[0056] The specific process includes:

[0057] Assume that in a D There are n A population of particles: X=[X 1 ,X 2 ,...,X n ] , where X n is the nth particle;

[0058] The first i A particle is represented as a D-dimensional vector: X i =[x i,1 ,x i,2 ,...,x i,D ] T , which represents the i A potential solution for a particle in the D-dimensional solution space. The fitness value corresponding to each particle can be calculated based on the objective function, that is:

[0059] No. i The velocity of a particle is: V i =[v i,1 ,v i,2 ,...,v i,D ] T ;

[0060] Its individual extreme values ​​are: P i =[p i,1 ,p i,2 ,...,p i,D ] T ;

[0061] The extreme values ​​of the group are: P g =[p g,1 ,p g,2 ,...,p g,D ] T ;

[0062] In each iteration, particles update their own speed and position through individual extreme values ​​and group extreme values. The update formula is:

[0063] ;

[0064] Where, oh is the weight coefficient; d is the dimension number, d=1,2,…,D ; Corner mark i is the particle individual number, i=1, 2,…,n ; The subscript g is the group number; k is the current iteration number; V is the particle velocity; c 1 and c 2 is a non-negative constant, also known as the acceleration factor; r 1 and r 2 is a random number distributed between [0, 1].

[0065] In this application, in order to prevent blind search of particles, the particle position and particle velocity are restricted to the interval, that is:

[0066] X ∈[ -X max , X max ], V ∈[ -V max , V max ];

[0067] Where, X max is the maximum value of the particle population, V max is the maximum particle velocity.

[0068] The test layout of the steady-state temperature distortion test is optimized based on the particle swarm optimization algorithm (PSO), so that the optimal circumferential angle of fixed total temperature probes with different circumferential numbers in the steady-state temperature distortion test can be obtained.

[0069] The following combination Figure 2 to Figure 4 The steady-state temperature distortion test layout shown is intended to illustrate multi-state performance.

[0070] like Figure 2The figure shows the change in the accuracy of the objective function's optimal result as the population size increases for one embodiment of the present application, when 6 and 8 measurement points are arranged circumferentially (one fixed total temperature probe provides one circumferential measurement point). The figure illustrates the change in the sum of the relative errors when the population size is an integer multiple of 2, 5, 10, 20, and 30 of the number of circumferential measurement points (the dimension of the solution). As can be seen from the figure, when the population size is an integer multiple of 2 or 5, the method is prone to falling into local optima during the global search. Increasing the population size enhances the global search capability, resulting in better results when the population size is an integer multiple of 10 or more circumferential measurement points.

[0071] Figure 3 Figure 2 shows the temperature field parameter calculation results obtained for different numbers of circumferential measurement points in one embodiment of the present application (Figure A: 6 circumferential measurement points, Figure B: 8 circumferential measurement points, Figure C: 10 circumferential measurement points, Figure D: 12 circumferential measurement points, and Figure E: 14 circumferential measurement points). As the number of circumferential measurement points increases, the accuracy of the test layout optimization results gradually improves, and the relative error and sum gradually decrease. From the overall error distribution, the relative error primarily occurs in the small distortion range. This is primarily due to the small absolute value of the distortion-related variables in this small distortion range, resulting in larger errors. Furthermore, due to the small temperature distortion range, the limited number of measurement points makes it difficult to capture temperature field characteristics, resulting in larger relative errors in the 1-sector heating and 1-2-sector heating states. As the number of circumferential measurement points increases from 6 to 14, the relative error and sum decreases from 19.4% to 4.0%. Therefore, increasing the number of circumferential measurement points is effective in achieving a more accurate test layout.

[0072] Figure 4 Shown is a temperature field measurement distribution diagram for different numbers of circumferential measuring points (6 circumferential measuring points, 8 circumferential measuring points, 10 circumferential measuring points, 12 circumferential measuring points, and 14 circumferential measuring points) in one embodiment of the present application. By comparing the temperature fields under different numbers of measuring points, it can be seen that as the number of measuring points increases, the temperature field can more finely depict the characteristics of the high-temperature zone. The measurement results show that the range of the high-temperature zone gradually becomes more accurate, and the internal details of the temperature field become clearer. This feature is particularly evident when heating in one sector. When there are 6 or 10 circumferential measuring points, there is only one measuring point in one sector, and the high-temperature zone presents a spike structure; when the number of measuring points increases to 12, the characteristics of the high-temperature zone are manifested as a flat peak structure. During multi-sector heating, as the number of measuring points increases, the temperature field distribution characteristics in the high-temperature zone gradually become significant, and the support plate wake in the high-temperature zone gradually appears.

[0073] The above results show that the steady-state temperature distortion inlet temperature test layout method of the present application has good convergence and high calculation accuracy, and can quickly carry out temperature distortion test measurements.

[0074] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A method for testing the inlet temperature of a steady-state temperature distortion, characterized in that: include: S10, constructing a mathematical model of the temperature field of the measurement section in the steady-state temperature distortion test and a mathematical model of the test layout for temperature measurement using a fixed total temperature probe; S20, determining temperature field parameters used to describe temperature field distortion characteristics, calculating the relative error sum between the temperature field parameters under the prior flow field and the temperature field parameters at corresponding coordinates of the test layout, thereby determining the optimization target of the test layout. The process includes: The average temperature of the measurement section under the prior flow field (T F,av ) real , average temperature of high temperature zone (T θ+av ) real and the circumferential dimension of the high temperature zone (θ + ) real By obtaining the temperature at the corresponding measuring point coordinates of the test layout, the average temperature of the measuring section under the test layout (T F,av ) test , average temperature of high temperature zone (T θ+av ) test and the circumferential dimension of the high temperature zone (θ + ) test ; The relative error caused by the measurement point position error in the test layout is obtained based on the temperature field parameters under the prior flow field and the temperature field parameters at the corresponding coordinates of the test layout: The relative error and error are: error = error1 + error2 + error3, where error1 is the relative error of the average temperature of the measured section, error2 is the relative error of the average temperature of the high temperature area, and error3 is the relative error of the circumferential dimension of the high temperature area. S30, taking the circumferential angle of the fixed total temperature probe in the test layout as the optimization parameter and the relative error sum of the temperature field parameters as the optimization target, an optimization algorithm is used to optimize the circumferential angle of the fixed total temperature probe in the test layout, thereby obtaining the optimal circumferential angle of fixed total temperature probes with different circumferential numbers in the steady-state temperature distortion test.

2. The method for testing the steady-state temperature distortion inlet temperature according to claim 1, wherein: The mathematical model of the temperature field of the measurement section is: T=f i (r,θ),i=1,2,...,N; Where T is the total temperature field function of the measurement section, r and θ are the radius and angle in the polar coordinate system, and f i (r, θ) represents the total temperature at the spatial position (r, θ) in the i-th sector, and the subscript i indicates the sector in the heating state, where i = 1, 2, ..., N corresponds to sector 1, sectors 1 to 2, ..., sectors 1 to N, respectively, and N is a natural number.

3. The steady-state temperature distortion inlet temperature test layout method according to claim 2, characterized in that: The mathematical model of the test layout for temperature measurement using a fixed total temperature probe is: T p =f i (r j ,i k ); Among them, T p represents the measured temperature of the pth sensing part, (r j ,θ k ) represents the spatial position of the sensing part in polar coordinates, j and k represent the radial and circumferential positions of the sensing part, respectively.

4. The method for testing the steady-state temperature distortion inlet temperature according to claim 3, wherein: The process of determining the temperature field parameters used to describe the temperature field distortion characteristics includes: According to the average temperature T of the measuring section F,av , average temperature of high temperature zone T θ+av And the circumferential angle distribution of high temperature area And the known incoming flow temperature T0, calculate the temperature distortion index, which includes the average relative temperature rise δT2, the circumferential non-uniformity of the temperature field and the circumferential dimension θ of the high temperature zone + : By analyzing the calculation expression of the temperature distortion index, it is found that the average relative temperature rise δT2 of the surface is determined by the incoming flow temperature T0 and the average temperature of the measuring section T F,av Determine the circumferential non-uniformity of the temperature field The average temperature of the measuring section T F,av and the average temperature of the high temperature zone T θ+av Decide; According to the analysis results of the calculation expression of the temperature distortion index, the average temperature T of the measurement section is determined F,av , average temperature of high temperature zone T θ+av and the circumferential dimension θ of the high temperature zone + Three temperature field parameters are used to describe the temperature field distortion characteristics.

5. The steady-state temperature distortion inlet temperature test layout method according to claim 4, characterized in that: The particle swarm optimization algorithm is used to optimize the circumferential angle of the fixed total temperature probe in the test layout. The process includes: First, a group of particles is initialized in the solution space. Each particle represents a potential optimal solution to the extreme value optimization problem. The characteristics of the particle are characterized by three indicators: the particle position, which represents the circumferential angle of the fixed total temperature probe in the test layout; the particle velocity, which represents the change in the circumferential angle of the fixed total temperature probe in the test layout; and the particle fitness, which represents the relative error of the temperature field parameters. Particles move in the solution space, and the particle position and particle velocity are updated by tracking individual extreme values ​​and group extreme values. The fitness value is calculated every time the particle is updated, and the individual extreme value and group extreme value are updated by comparing the fitness value of the new particle. When the fitness value of the new particle is less than the optimization target, the optimal particle position, particle velocity and particle fitness are obtained, thereby obtaining the optimal temperature field parameters.

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