Turbine blade radiation temperature measuring device and temperature measuring method thereof

Abstract

The present invention provides a turbine blade radiation temperature measurement device and a temperature measurement method thereof, wherein the device comprises: a beam deflection device, a first detector device, a second detector device and a third detector device; a radiation beam emitted by a turbine blade is incident on the beam deflection device, and the radiation beam is incident on a first dichroic mirror after passing through the beam deflection device to be divided into a first beam and a second beam; the first beam is incident on the first detector device to obtain a radiation signal at a first wavelength; the third beam is incident on the second detector device to obtain a radiation signal at a second wavelength; the fourth beam is incident on the third detector device to obtain a radiation signal at a third wavelength; after distinguishing the turbine blade target surface radiation signal and the environment surface radiation signal among the three radiation signals, the temperature at the target position on the turbine blade is inverted after being corrected by the environment reflection energy. The present invention can effectively reduce measurement errors.

Description

Technical Field

[0001] The invention relates to the technical field of radiation temperature measurement, and in particular to a turbine blade radiation temperature measurement device and a temperature measurement method thereof. Background Art

[0002] The aircraft engine is the most important core part of the aircraft. To ensure the high performance and high efficiency of the aircraft engine, the turbine blades are often required to work under high temperature and high pressure conditions. In order to avoid damage from high temperature environment, the surface of the turbine blades is coated with a thermal barrier coating, which increases the operating temperature of the turbine blades and even exceeds the melting point of the material. However, long-term high-load operation can easily cause the thermal barrier coating to fall off, making the blades susceptible to high temperature damage, threatening flight safety. Therefore, measuring the temperature distribution of the turbine blades can ensure that the turbine blades work within a safe temperature range, and at the same time, hidden dangers can be discovered in time when the thermal barrier coating is damaged. In addition, during the development and testing of aircraft engines, accurate measurement of the surface temperature distribution of turbine blades can provide key data for blade operation status analysis and engine development.

[0003] Temperature measurement technology is mainly divided into contact temperature measurement technology and non-contact temperature measurement. The contact temperature measurement methods for aviation turbine blades are mainly thermocouple method and temperature indicating paint method: although the thermocouple method is accurate in temperature measurement, it is troublesome to install and has poor adhesion; although the temperature indicating paint method can measure parts that are difficult to measure with thermocouples, it has low accuracy and requires the disassembly of parts for interpretation, making it difficult to monitor the temperature of turbine blades in real time. Radiation temperature measurement provides an effective non-contact temperature measurement method for measuring the temperature distribution of turbine blades. It is based on Planck radiation theory and uses a radiation pyrometer to measure the thermal radiation of the target surface to obtain the target temperature. However, in the temperature measurement of turbine blades, there are two main problems with radiation temperature measurement: one is the problem of the surface emissivity of the turbine blades. The surface emissivity of the turbine blades changes with the increase of working time, and the surface temperature of the turbine blades will also change the emissivity; the other is the problem of environmental radiation influence. The turbine blades work in a high temperature environment. When the pyrometer measures the radiation from the turbine blades, the environmental radiation emitted by the turbine blades and the thermal radiation of the blades themselves will enter the pyrometer together, resulting in the obtained turbine blade temperature being higher than the actual temperature, which brings non-negligible measurement errors. At present, the existing turbine blade temperature measurement instruments on the market mainly use the single-band temperature measurement method. The temperature measurement accuracy of this method will be affected by the surface emissivity and background radiation. Therefore, solving the influence of surface emissivity and background radiation and achieving accurate measurement of turbine blade temperature is of great significance to engine operation safety monitoring and engine research and development. Summary of the invention

[0004] In view of the above problems, the purpose of the present invention is to propose a turbine blade radiation temperature measurement device and a temperature measurement method thereof, which collects the radiation energy of multiple positions of the turbine blade in three different bands, and the environmental energy data collected in the three bands, and substitutes them into the error function of the radiation temperature measurement method, and substitutes the initial temperature value selected by the step length into the genetic algorithm to divide the temperature working range of the turbine blade, and take a temperature value as the initial value in each temperature range for solution, and finally compare all the obtained results to obtain the minimum error function value and the corresponding temperature, which is considered to be the true temperature of the turbine blade surface. This method can realize the radiation temperature inversion of unknown emissivity turbine blades in the radiation environment, correct the influence of environmental radiation without predicting the emissivity model of the blade, and can effectively reduce the measurement error.

[0005] To achieve the above object, the present invention adopts the following specific technical solutions:

[0006] The present invention provides a turbine blade radiation temperature measurement method, which uses a turbine blade radiation temperature measurement device to achieve temperature measurement, and the temperature measurement device includes: a beam deflection device, two dichroic mirrors, a first detector device, a second detector device and a third detector device;

[0007] The radiation beam emitted by the turbine blade is incident on the beam folding device, and after passing through the beam folding device, the radiation beam is incident on the first dichroic mirror and is divided into a first beam and a second beam;

[0008] The first light beam is incident on the first detector device to obtain a radiation signal at a first wavelength; the second light beam is incident on the second dichroic mirror to be divided into a third light beam and a fourth light beam; the third light beam is incident on the second detector device to obtain a radiation signal at a second wavelength; the fourth light beam is incident on the third detector device to obtain a radiation signal at a third wavelength;

[0009] After distinguishing the turbine blade target surface radiation signal and the environment surface radiation signal among the three radiation signals, the temperature at the target position on the turbine blade is inverted after the environment reflection energy correction;

[0010] The following steps are involved:

[0011] S1. Establish a radiation model and calculate the radiation signal at any point on the turbine blade through the radiation model;

[0012] S(λ l , T i )=ε b (λ l , T i )S B (λ l , T i )+[1-ε b (λl , T i )]S e (λ l , T i )+S D (λ l )

[0013] in,

[0014] S(λ l , T i ) is the wavelength λ of the i-th position on the turbine blade l The radiation signal measured at

[0015] ε b (λ l , T i ) is the wavelength λ of the i-th position l The emissivity at ;

[0016] S B (λ l , T i ) is measured by a pyrometer at a wavelength λ l The level output signal at

[0017] S e (λ l , T i ) is received by the pyrometer at the i-th position of the turbine blade at wavelength λ i The level signal caused by the infrared radiation equal to the ambient radiation in the place;

[0018] S D (λ l ) is the detector noise;

[0019] S2, collect the radiation signal of the turbine blade surface, and obtain the target surface radiation S(λ l , T i ) and ambient surface radiation S e (λ l , T i ), and substitute them into the error function of the radiation temperature measurement method:

[0020]

[0021] Where, l = 1, 2, 3; i = 1, 2, 3;

[0022] S3, set the preset step size, divide the actual operating temperature range of the turbine blade, and obtain the endpoint temperature value T of the divided area 1b , T 2b , T3b …as the initial value and substituted into the error function of step S3, and the genetic algorithm is used to solve the error function value and the corresponding temperature value corresponding to different temperature initial values;

[0023] S4. The temperature value corresponding to the minimum error value calculated by the error function is used as the actual temperature of the target point surface on the turbine blade.

[0024] Preferably, the light beam deflection device comprises: a reflector, a condenser and a collimator; the reflector is used to realize the swinging motion;

[0025] After being reflected by the reflector, the radiation beam is converged to the primary image plane by a condenser, where a field stop or optical fiber is arranged;

[0026] The radiation beam passes through the field aperture or the optical fiber and is then collimated by the collimator before entering the first dichroic mirror.

[0027] Preferably, the size of the field stop diameter determines the size of the object surface;

[0028] The size of the optical fiber core diameter determines the size of the object surface.

[0029] Preferably, the first detector device comprises: a first filter, a first focusing mirror and a first detector;

[0030] The first light beam is filtered by the first filter to obtain a light beam at the first wavelength, which is focused onto the target surface of the first detector by the first focusing lens;

[0031] The second detector device includes: a second filter, a second focusing mirror and a second detector;

[0032] The third light beam is filtered by the second filter to obtain a light beam at the second wavelength, which is focused onto the target surface of the second detector by the second focusing lens;

[0033] The third detector device comprises: a third filter, a third focusing mirror and a third detector;

[0034] The fourth light beam is filtered by the third filter to obtain a light beam at a third wavelength, which is focused onto the target surface of the third detector by the third focusing lens.

[0035] Preferably, the method further includes a preprocessing step S0, wherein the three detector devices are calibrated using a high-temperature black body to obtain a relationship S between the black body temperature and the three wavelength signals. B (λ l , T i )(l=1,2,3;i=1,2,3) and detector noise S D (λ l )(l=1,2,3).

[0036] Preferably, the emissivity ε b (λ l , T i ) is assumed to be linear with temperature:

[0037] ε b (λ l , T i )=ε b (λ l , T1)[1+k l (T i -T1)].

[0038] Compared with the existing technology, the present invention collects the radiation energy of multiple positions of turbine blades in three different bands, as well as the environmental energy data collected in the three bands, and substitutes them into the error function of the radiation temperature measurement method, substitutes the initial temperature value selected by the step length into the genetic algorithm, divides the temperature working range of the turbine blade, takes a temperature value as the initial value in each temperature range for solution, and finally compares all the results obtained to obtain the minimum error function value and the corresponding temperature, which is considered to be the true temperature of the turbine blade surface. The present invention can realize the radiation temperature inversion of unknown emissivity turbine blades in the radiation environment, correct the influence of environmental radiation without predicting the emissivity model of the blade, and can effectively reduce the measurement error. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 Schematic diagram of the structure of a turbine blade radiation temperature measurement device provided according to the first embodiment of the present invention.

[0040] Figure 2 Schematic diagram of the structure of a turbine blade radiation temperature measurement device provided according to the second embodiment of the present invention.

[0041] Figure 3 It is a schematic diagram of a measurement scheme of a turbine blade radiation temperature measurement device provided according to an embodiment of the present invention.

[0042] Figure 4 It is a principle block diagram of a turbine blade radiation temperature measurement device provided according to an embodiment of the present invention.

[0043] Figure 5 It is a flow chart of a method for measuring temperature of a turbine blade by radiation according to an embodiment of the present invention.

[0044] The reference numerals therein include: turbine blade 1, reflector 2, condenser 3, collimator 4, first dichroic mirror 5, first filter 6, first focusing mirror 7, first detector 8, second dichroic mirror 9, second filter 10, second focusing mirror 11, second detector 12, third filter 13, third focusing mirror 14, third detector 15 and optical fiber 16. DETAILED DESCRIPTION

[0045] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, the same modules are represented by the same reference numerals. In the case of the same reference numerals, their names and functions are also the same. Therefore, the detailed description thereof will not be repeated.

[0046] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation of the present invention.

[0047] Figure 1 A schematic structural diagram of a turbine blade radiation temperature measurement device provided according to a first embodiment of the present invention is shown.

[0048] Figure 2 A schematic structural diagram of a turbine blade radiation temperature measurement device provided according to a second embodiment of the present invention is shown.

[0049] like Figure 1 and Figure 2 As shown, the turbine blade radiation temperature measurement device provided by the first embodiment of the present invention includes: a light beam deflection device, two dichroic mirrors, a first detector device, a second detector device and a third detector device.

[0050] The radiation beam emitted by the turbine blade 1 is incident on the beam deflection device.

[0051] The light beam deflection device comprises: a reflector 2, a condenser 3 and a collimator 4.

[0052] After being reflected by the reflector 2, the radiation beam is converged by the condenser 3 onto the primary image plane. A field stop of a suitable size is provided at the primary image plane, and the size of the field stop determines the size of the object surface.

[0053] The reflector 2 realizes the sweeping action according to the control signal sent by the sweeping controller, and at the same time, along with the rotation of the turbine blade 1, the radiation data of more positions on the turbine blade 1 can be obtained.

[0054] The radiation beam passes through the field aperture, is collimated by the collimator 4, and then is incident on the first dichroic mirror 5. The radiation beam is divided into a first beam and a second beam by the first dichroic mirror 5.

[0055] The first light beam is incident on the first detector device;

[0056] The first detector device comprises: a first filter 6 , a first focusing mirror 7 and a first detector 8 .

[0057] After being filtered by the first filter 6 , the first light beam is focused onto the target surface of the first detector 8 by the first focusing mirror 7 .

[0058] The second light beam is incident on the second dichroic mirror 9 and is split into a third light beam and a fourth light beam by the second dichroic mirror 9 .

[0059] The third light beam is incident on the second detector device;

[0060] The second detector device includes: a second filter 10 , a second focusing mirror 11 and a second detector 12 .

[0061] After being filtered by the second filter 10 , the third light beam is focused onto the target surface of the second detector 12 by the second focusing mirror 11 .

[0062] The fourth light beam is incident on the third detector device;

[0063] The third detector device includes a third filter 13 , a third focusing lens 14 and a third detector 15 .

[0064] After being filtered by the third filter 13 , the fourth light beam is focused onto the target surface of the third detector 15 by the third focusing lens 14 .

[0065] The detector target surface converts the radiation energy of the received radiation beam into a corresponding voltage signal, which is then filtered, decoupled, amplified, and processed by the back-end circuit. Finally, it is collected by a high-speed acquisition card and stored on the PC.

[0066] The turbine blade radiation temperature measurement device provided by the second embodiment of the present invention is provided with an optical fiber 16 between the condenser 3 and the collimator 4 for long-distance transmission of the radiation beam. The end face of the optical fiber 16 is provided at the primary image plane, and the core diameter determines the size of the object surface.

[0067] Figure 3 It is a schematic diagram of a measurement scheme of a turbine blade radiation temperature measurement device provided according to an embodiment of the present invention.

[0068] Figure 4 It is a principle block diagram of a turbine blade radiation temperature measurement device provided according to an embodiment of the present invention.

[0069] like Figure 3 and Figure 4 As shown, the principle of the turbine blade radiation temperature measurement device provided by the embodiment of the present invention is:

[0070] The sweep controller sends a control signal to control the reflector to sweep, so that the detector collects the radiation from the ambient surface and the target surface on the turbine blades. At the same time, the control signal is sent to the PC to distinguish the ambient surface signal from the target surface signal on the turbine blades.

[0071] The ambient surface radiation and the target surface radiation on the turbine blades enter the three-band radiation temperature measurement system successively, undergo color separation, filtering, photoelectric conversion and signal processing, and are finally collected and transmitted to the PC via an acquisition card. The PC calculates the ambient surface radiation and the target surface radiation on the turbine blades, and uses the three-wavelength radiation temperature measurement method to invert the temperature at the target position on the turbine blade after correction of the ambient reflection energy.

[0072] The present invention collects the radiation energy in three different bands of multiple target points with different temperatures on the turbine blades and the reflected radiation data from the surrounding environment, adopts a specially constructed error function using the least squares method, and then solves the solution at the minimum value of the error function through a genetic algorithm to obtain the true temperature of all target points.

[0073] The present invention is based on Planck's blackbody radiation formula:

[0074]

[0075] in,

[0076] c1=3.7418×10 -16 Wm 2 , is the first radiation constant;

[0077] c2=1.4388×10 -2 mK, is the first radiation constant;

[0078] λ is the wavelength of radiation from the object;

[0079] T is the absolute temperature of the object.

[0080] For actual objects (non-black bodies), their radiation characteristics must be multiplied by a factor ε based on the blackbody radiation formula. This factor is defined as the emissivity. The emissivity of an object is defined as the ratio of the radiation capacity of the object to that of a blackbody at the same temperature:

[0081]

[0082] in,

[0083] M1 is the radiation energy of the object at temperature T;

[0084] M2 is the radiant energy of the black body at temperature T.

[0085] The turbine blade radiation energy collected by the three detectors of the present invention mainly includes the thermal radiation of the blade itself and the radiation of the surrounding blades reflected by it. The radiation energy of the surrounding blades reflected here is calculated based on the actual measurement results combined with the radiation angle factor of the corresponding structure (such as the blade and the inner wall of the combustion chamber) to the blade. Therefore, for the three selected bands, the energy received by the detector can be expressed as:

[0086] S(λ l , T i )=ε b (λ l , T i )S B (λ l , T i )+[1-ε b (λ l , T i )]S e (λ l , T i )+S D (λ l ) (3)

[0087] in,

[0088] S(λ l , T i ) is the measurement of the i-th position at wavelength λ l The detector radiation signal obtained at

[0089] ε b (λ l , T i ) is the wavelength λ of the i-th position l The emissivity at ;

[0090] S B (λ l , T i ) is the pyrometer measuring the black body with the same temperature as the target blade at wavelength λ l The level output signal obtained at

[0091] S e (λ l , T i ) is the wavelength λ of the pyrometer receiving and the target blade i-th position point l The level signal caused by the infrared radiation equal to the ambient radiation in the place;

[0092] S D (λ l ) is the detector noise.

[0093] Assume that the emissivity varies linearly with temperature within the temperature range of the three target points on the turbine blade, that is:

[0094] ε b (λ l , T i )=ε b (λ l , T1)[1+k l (Ti -T1)] (4)

[0095] Among them, k l is the parameter related to the slope in the equation of the straight line;

[0096] k l ·ε b (λ l , T) is the slope of the straight line equation.

[0097] When the pyrometer collects three-band radiation from at least three positions on the turbine blade (three points are taken as an example here), it can be obtained from formula (3):

[0098] e 11 =ε b (λ1,T1)S B (λ1,T1)+[1-ε b (λ1,T1)]S e (λ1,T1)+S D (λ1, T1)-S(λ1, T1) (5)

[0099] e 21 =ε b (λ2,T1)S B (λ2,T1)+[1-ε b (λ2,T1)]S e (λ2,T1)+S D (λ2, T1)-S(λ2, T1) (6)

[0100] e 31 =ε b (λ3,T1)S B (λ3, T1)+[1-ε b (λ3, T1)]S e (λ3, T1)+S D (λ3, T1)-S(λ3, T1) (7)

[0101] e 12 =ε b (λ1,T2)S B (λ1,T2)+[1-ε b (λ1,T2)]S e (λ1,T2)+S D (λ1, T2)-S(λ1, T2) (8)

[0102] e 22 =ε b (λ2,T2)S B (λ2,T2)+[1-ε b (λ2, T2)]Se (λ2,T2)+S D (λ2, T2)-S(λ2, T2) (9)

[0103] e 32 =ε b (λ3,T2)S B (λ3, T2)+[1-ε b (λ3, T2)]S e (λ3, T2)+S D (λ3, T2)-S(λ3, T2) (10)

[0104] e 13 =ε b (λ1,T3)S B (λ1,T3)+[1-ε b (λ1,T3)]S e (λ1,T3)+S D (λ1, T3)-S(λ1, T3) (11)

[0105] e 23 =ε b (λ2,T3)S B (λ2,T3)+[1-ε b (λ2, T3)]S e (λ2,T3)+S D (λ2, T3)-S(λ2, T3) (12)

[0106] e 33 =ε b (λ3,T3)S B (λ3, T3)+[1-ε b (λ3, T3)]S e (λ3, T3)+S D (λ3, T3)-S(λ3, T3) (13)

[0107] In the system of equations (5)-(13), substitute equation (4) into each equation and set the values ​​of all nine equations to 0 (e li =0, l=1,2,3, i=1,2,3), we can see that the system of equations has nine unknowns (T1, T2, T3, k1, k2, k3, ε b (λ1,T1),ε b (λ2,T1),ε b(λ3, T1)), other physical quantities can be obtained through measurement or can be expressed as functions related to these nine physical quantities. However, due to the influence of factors such as noise in actual measurement, it is difficult to find a solution that satisfies all equations at the same time. However, the least square solution of the equation system can be obtained by solving algorithms for nonlinear equation systems such as genetic algorithms, that is, the solution that satisfies equation (14), and the temperature and emissivity of all positions can be inverted.

[0108]

[0109] Engine operating temperature T1, emissivity ε b and parameter k l The range of values ​​can be determined in advance based on empirical values, and the speed and accuracy of the solution can be improved by limiting the search range. The temperature variation range is large, and the selection of its initial value divides the operating temperature range of the turbine blade according to the step size, and substitutes them into the genetic algorithm for solution. A set of temperature solutions and temperature difference function value data can be obtained. Finally, the error function values ​​corresponding to these temperature solutions are compared to obtain the minimum error function value and its corresponding temperature, which is considered to be the true temperature of the turbine blade surface.

[0110] Figure 5 A schematic flow chart of a method for measuring temperature by radiation of a turbine blade provided according to an embodiment of the present invention is shown.

[0111] like Figure 5 As shown, the turbine blade radiation temperature measurement method provided by the embodiment of the present invention includes the following steps:

[0112] Preprocessing step S0: Use a high-temperature black body to calibrate the three detector devices, and obtain the relationship between the black body temperature and the three wavelength signals S B (λ l , T i )(l=1,2,3;i=1,2,3) and detector noise S D (λ l )(l=1,2,3).

[0113] S1. Establish a radiation model and calculate the radiation signal at any point on the turbine blade through the radiation model.

[0114] S(λ l , T i )=ε b (λ l , T i )S B (λ l , T i )+[1-ε b (λ l , T i )]S e (λl， T i )+S D (λ l )

[0115] in,

[0116] S(λ l , T i ) is the wavelength λ of the i-th position on the turbine blade l The detector radiation signal measured at

[0117] ε b (λ l , T i ) is the wavelength λ of the i-th position l The emissivity at ;

[0118] S B (λ l , T i ) is the pyrometer measuring the wavelength λ of a black body with the same temperature as the turbine blade l The level output signal obtained at

[0119] S e (λ l , T i ) is the wavelength λ of the pyrometer receiving and the i-th position of the turbine blade l The level signal caused by the infrared radiation equal to the ambient radiation in the place;

[0120] S D (λ l ) is the detector noise.

[0121] The emissivity ε b (λ l , T i ) is assumed to be linear with temperature:

[0122] ε b (λ l , T i )=ε b (λ l , T1)[1+k l (T i -T1)]

[0123] S2, collect the radiation on the surface of the turbine blade in operation, and obtain the actual radiation S(λ l , T i ) and the calculated ambient radiation S e (λ l , T i ), and substitute it into the error function of the radiation temperature measurement method:

[0124]

[0125] Among them, l=1, 2, 3; i=1, 2, 3.

[0126] S3, set the preset step size, divide the actual operating temperature range of the turbine blade, and obtain the endpoint temperature value T of the divided area 1b , T 2b , T 3b ...is substituted into the error function of step S3 as the initial value, and the genetic algorithm is used to solve the error function value and the corresponding temperature value corresponding to different temperature initial values.

[0127] S4. The temperature value corresponding to the minimum value calculated by the error function is used as the actual temperature of the multiple target points on the measured turbine blade.

[0128] The radiation temperature measurement method disclosed in the present invention only needs to measure and calculate the actual radiation of multiple points of the turbine blade at three wavelengths and the reflected radiation from the surrounding environment, so as to measure the surface temperature of the turbine blade including the reflected radiation under the condition of unknown emissivity.

[0129] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

[0130] The above specific implementations of the present invention do not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A method for measuring the temperature of a turbine blade by radiation, using a turbine blade radiation temperature measuring device to measure the temperature, the temperature measuring device comprising: a beam deflecting device, two dichroic mirrors, a first detector device, a second detector device and a third detector device; The radiation beam emitted by the turbine blade is incident on the beam folding device, and after passing through the beam folding device, the radiation beam is incident on the first dichroic mirror and is divided into a first beam and a second beam; The first light beam is incident on the first detector device to obtain a radiation signal at a first wavelength; the second light beam is incident on the second dichroic mirror to be divided into a third light beam and a fourth light beam; the third light beam is incident on the second detector device to obtain a radiation signal at a second wavelength; the fourth light beam is incident on the third detector device to obtain a radiation signal at a third wavelength; After distinguishing the turbine blade target surface radiation signal and the environment surface radiation signal among the three radiation signals, the temperature at the target position on the turbine blade is inverted after the environment reflection energy correction; It is characterized by comprising the following steps: S1. Establishing a radiation model, and calculating the radiation signal at any position point on the turbine blade by using the radiation model; in, The turbine blade The position point is at the wavelength The radiation signal measured at It is The position point is at the wavelength The emissivity at ; The wavelength of a black body at the same temperature as the turbine blade is measured by a pyrometer. The level output signal at The pyrometer receives the The position point is at the wavelength The level signal caused by the infrared radiation equal to the ambient radiation in the place; is the detector noise; S2. Collect the radiation signal of the turbine blade surface to obtain the target surface radiation of the turbine blade at three wavelengths. and ambient surface radiation , and substitute them into the error function of the radiation temperature measurement method: in, ; The genetic algorithm is used to obtain the solution that satisfies the following equation, and the temperature and emissivity of all locations are inverted: ； S3, setting a preset step size, dividing the actual operating temperature range of the turbine blade, and obtaining the endpoint temperature values ​​of the divided areas , , …as an initial value and substituted into the error function of step S3, and using a genetic algorithm to solve the error function value and the corresponding temperature value corresponding to different temperature initial values; S4. Using the temperature value corresponding to the minimum error value calculated by the error function as the actual temperature of the target point surface on the turbine blade.

2. The turbine blade radiation temperature measurement method according to claim 1, characterized in that: The beam deflection device comprises: a reflector, a condenser and a collimator; the reflector is used to realize the swinging and scanning action; After being reflected by the reflector, the radiation beam is converged to a primary image plane by the condenser, and a field stop or an optical fiber is arranged at the primary image plane; The radiation beam passes through the field aperture or the optical fiber and is then collimated by the collimator before entering the first dichroic mirror.

3. The turbine blade radiation temperature measurement method according to claim 2, characterized in that: The size of the field stop diameter determines the size of the object surface; The size of the optical fiber core diameter determines the size of the object surface.

4. The method for measuring turbine blade radiation temperature according to claim 3, characterized in that: The first detector device comprises: a first filter, a first focusing lens and a first detector; The first light beam is filtered by the first filter to obtain a light beam at a first wavelength, and is focused onto a target surface of the first detector by the first focusing lens; The second detector device comprises: a second filter, a second focusing mirror and a second detector; The third light beam is filtered by the second filter to obtain a light beam at a second wavelength, and is focused onto the target surface of the second detector by the second focusing mirror; The third detector device comprises: a third filter, a third focusing lens and a third detector; The fourth light beam is filtered by the third filter to obtain a light beam at a third wavelength, which is focused onto the target surface of the third detector by the third focusing lens.

5. The turbine blade radiation temperature measurement method according to claim 4, characterized in that: The method also includes a preprocessing step S0, using a high-temperature black body to calibrate the three detector devices to obtain the relationship between the black body temperature and the three wavelength signals. and detector noise .

6. The turbine blade radiation temperature measurement method according to claim 5, characterized in that: The emissivity Assume that it is linear with temperature: 。

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