A non-contact turbine blade film hole diameter measurement method and system

Abstract

The application provides a non-contact turbine blade film hole diameter measurement method, which comprises the following steps: extending a micro light source into the inner cavity of a turbine blade, arranging a receiving plate outside the inner cavity of the turbine blade; controlling the micro light source to generate a light beam, so that the light beam passes through the film hole of the turbine blade and forms an image on the receiving plate, thereby obtaining the position, shape and light intensity of the light beam on the receiving plate and the turbine blade at a first angle; adjusting the angle and position of the receiving plate relative to the turbine blade, and repeating the above process to obtain the position, shape and light intensity of the light beam on the receiving plate and the turbine blade at a second angle; and obtaining the angle and diameter of the film hole according to the position, shape and light intensity of the light beam at the first angle and the position, shape and light intensity of the light beam at the second angle.

Description

Technical Field

[0001] This application belongs to the field of aero-engine technology, and specifically relates to a non-contact method and system for measuring the diameter of film pores in turbine blades. Background Technology

[0002] The turbine is the main power-generating component of an aero-engine. As aero-engine performance improves, the turbine inlet temperature also increases. Due to this increased turbine inlet temperature, existing turbine blades often require the machining of film cooling holes. Cooling gas from inside the blade cavity exits through these holes, forming a cool gas film on the blade wall. This film reduces the convective heat transfer temperature difference between the combustion gas and the blade wall, thus lowering the blade wall temperature. For example, high-pressure turbine guide vanes with composite cooling blade structures often have hundreds or even thousands of film cooling holes on their surface.

[0003] The diameter of the film cooling holes is an important parameter affecting the cooling effect of turbine blades. Because the diameter of the film cooling holes is very prone to shrinkage during subsequent processing (such as spraying thermal barrier coatings) and long-term use, it is necessary to measure the diameter of the film cooling holes of the blades frequently, such as after the blades are drilled, after the blades are coated with thermal barrier coatings, and after the blades have been in operation.

[0004] The film cooling vents on turbine blades are relatively small, typically 0.25-0.8 mm in diameter, and there are many of them. Currently, the diameter of the film cooling vents is generally measured using a feeler gauge. This method works by inserting feeler gauges of different sizes into a specific film cooling vent on the blade, finding the one that perfectly matches the vent diameter, and recording its size as the diameter of the vent being measured.

[0005] The disadvantages of this method are: the measurement is cumbersome and time-consuming; the angle of entry will affect the measured size; manual recording is required and prone to errors; and since this method is a contact measurement, it can easily affect the blade surface. When the blade is in a multi-unit assembly state, some apertures cannot be measured using this method due to obstruction. Summary of the Invention

[0006] The purpose of this application is to provide a non-contact method and system for measuring the diameter of film vents in turbine blades, so as to solve or alleviate at least one of the problems in the prior art.

[0007] The technical solution of this application is: a non-contact method for measuring the diameter of film gas vents in turbine blades, the method comprising:

[0008] A tiny light source is inserted into the inner cavity of the turbine blade, and a receiving plate is placed on the outside of the inner cavity of the turbine blade.

[0009] A tiny light source is controlled to generate a light beam, which passes through the film aperture of the turbine blade and forms an image on the receiving plate, thereby obtaining the position, shape, and intensity of the light beam on the receiving plate and the turbine blade at a first angle.

[0010] Adjust the angle and position of the receiving plate relative to the turbine blade, and repeat the above process to obtain the beam position, shape and intensity of the beam between the receiving plate and the turbine blade at the second angle;

[0011] The angle and diameter of the air film aperture are obtained based on the position, shape, and intensity of the light beam at the first angle and the position, shape, and intensity of the light beam at the second angle.

[0012] In a preferred embodiment of this application, the micro light source is connected to an extension rod for controlling the movement of the micro light source within the turbine blade cavity.

[0013] In a preferred embodiment of this application, the receiving plate is connected to a light-sensing system, which can convert the light signal received by the receiving plate into an electrical signal, thereby realizing the detection and imaging of the beam position, shape and intensity.

[0014] In a preferred embodiment of this application, if the receiving plate cannot directly receive the light spot due to mutual obstruction between adjacent turbine blades, at least one plane mirror is placed between the turbine blade and the receiving plate, and the angle between the plane mirror and the air film hole is adjusted so that the receiving plate can receive the light beam reflected from the plane mirror.

[0015] In a preferred embodiment of this application, the process of obtaining the angle and diameter of the air film pores is as follows:

[0016] Calculate the maximum light intensity at each coordinate point of the multiple air film holes obtained on the receiving plate during the same measurement period;

[0017] The light spots obtained from multiple measuring holes at coordinate positions are sorted to obtain the order between the two measuring light spots and the measured film air holes on the turbine blade.

[0018] The location of the largest spot in the beam is identified to obtain the maximum light intensity region. For each measured aperture, there are two maximum light intensity regions.

[0019] Find the center point of the maximum light intensity zone, connect the two center points of the maximum light intensity zones of the same air film aperture, and the vector line formed is the center line of the air film aperture. Calculate the angle between the center line and the x and y axes, and you will get the angle of the air film aperture.

[0020] Connect the two regions with the highest light intensity of the same air film pore to form a cylinder, and calculate the diameter of the cylinder to obtain the diameter of the air film pore.

[0021] On the other hand, the technical solution provided in this application is: a system for implementing any of the above-described non-contact turbine blade film pore diameter measurement methods, the system comprising:

[0022] A micro-light source is disposed inside the turbine blade to generate a light beam that passes through the film gas aperture;

[0023] A receiving plate, positioned on the outer side of the inner cavity of the turbine blades, is used to receive the light beam generated by a tiny light source; and

[0024] A light-sensing system, connected to a receiving board, is used to convert the light signals received by the receiving board into electrical signals, thereby obtaining the position, shape, and intensity of the strongest light beam received by the receiving board.

[0025] The data processing device calculates the angle and diameter of the measured air film aperture based on the position, shape, and intensity of the strongest beam.

[0026] The non-contact turbine blade film pore diameter measurement method and system provided in this application can improve the measurement speed of film pores and can be used in multi-unit assembly mode. The measurement process is simple and the measurement accuracy is high. Attached Figure Description

[0027] To more clearly illustrate the technical solutions provided in this application, the accompanying drawings will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application.

[0028] Figure 1 This is a schematic diagram of the non-contact turbine blade film pore diameter measurement method of this application.

[0029] Figure 2 This is a schematic diagram of the non-contact turbine blade film pore diameter measurement process of this application.

[0030] Figure 3 This is a schematic diagram of the process for measuring the diameter of the film gas vents on a shielded, non-contact turbine blade.

[0031] Figure 4 This is a schematic diagram showing the measurement of the light spot and the area of ​​maximum light intensity.

[0032] Figure 5 A schematic diagram showing the connection of the region with the highest light intensity into a cylinder.

[0033] Figure label:

[0034] 1-Miniature Light Source

[0035] 2-Turbine blades

[0036] 3-Receiver board

[0037] 4-Tested air film pores

[0038] 5-Non-measuring film pores

[0039] 6-Obscuration

[0040] 7-plane mirror

[0041] 8-Measuring the light spot

[0042] 9-Maximum light intensity zone

[0043] 10-center line

[0044] 11-Cylinder Detailed Implementation

[0045] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings.

[0046] The purpose of this application is to provide a non-contact method for measuring the diameter of film gas holes in turbine blades, so as to improve the measurement speed of film gas holes and to perform the measurement in the state of multi-unit assembly.

[0047] like Figure 1 As shown, the non-contact turbine blade film pore diameter measurement method provided in this application includes the following steps:

[0048] S1. Insert a tiny light source into the inner cavity of the turbine blade.

[0049] like Figure 2 As shown, the micro light source 1 is a micro point light source or line light source that can be placed inside the turbine blade 2 cavity. The micro light source 1 can be connected to an extension rod so that it can move inside the turbine blade 2 cavity.

[0050] The micro light source 1 can extend into the inner cavity of the turbine blade 2 through existing holes or cavities that communicate with the inner cavity of the blade, such as small holes or tenon inlets on the working blade cover plate; or cold air inlets on the guide blade.

[0051] S2. Place the turbine blades in a darkroom environment.

[0052] Turbine blade 2 is fixed at its corresponding position in the dark chamber according to the coordinate system. There is no light in the dark chamber, and a receiving plate 3 is placed inside. The receiving plate 3 is a plane, which is connected to a light-sensing system (not shown). The light-sensing system can realize high-resolution detection of the position, shape, and light intensity of tiny light spots through the light signal received by the receiving plate 3.

[0053] By blocking the outlet position of the non-measuring film orifice 5 on the outer surface of the turbine blade 2 with a shield 6, multiple or more film orifices can be measured simultaneously, achieving reversible shielding measurement.

[0054] S3, Light Source Emission

[0055] Turn on the miniature light source 1, allowing the light beam to pass through the measured film gas aperture 4 of the turbine blade 2. Adjust the distance and angle between the turbine blade 2 and the receiving plate 3 to ensure that the light beams formed between the receiving plate 3 and the measured film gas aperture 4 do not overlap. If this cannot be achieved, perform measurements in batches.

[0056] Record the distance and angle between turbine blade 2 and receiving plate 3.

[0057] S4, Signal Reception

[0058] Turn on the optical signal transmission system so that the light beam generated by the tiny light source 1 passes through the measured air film hole 4 on the inner cavity of the turbine blade 2, and the light beam forms a light spot on the receiving plate 3.

[0059] The tiny light source 1 inside the turbine blade 2 is moved so that during the movement, the tiny light source 1 is as close as possible to and covers the inlet of each measured air film hole 3 on the inner wall surface of the turbine blade 2.

[0060] The photosensitive system converts photoelectric signals into electrical signals and records the position, shape, and intensity of the strongest beam of light received by the receiving plate 3 at each position during the movement by measuring the magnitude of the current at each position.

[0061] like Figure 3 As shown, if the receiving plate 3 cannot directly receive the light spot due to mutual obstruction between adjacent turbine blades, the angle between the plane mirror 7 and the measured air film hole 4 can be adjusted by placing a plane mirror 7 between the turbine blade and the receiving plate 3, so that the receiving plate 3 can receive the light reflected from the plane mirror 7.

[0062] Turn off the optical signal receiving system.

[0063] S5. Change the position of the receiving plate and repeat the measurement.

[0064] Adjust the position and angle of the receiving plate 3 relative to the turbine blade 2, and remeasure the position, shape and intensity of the light beam at this angle.

[0065] S6. Calculate the angle and diameter of the air film pores.

[0066] Based on the position, shape, and intensity of the light beam measured in two separate measurements, the angle and diameter of the measured air film aperture 4 are calculated. The calculation process is as follows:

[0067] S61. Calculate the maximum light intensity at each coordinate point during the same measurement period.

[0068] S62, such as Figure 4 As shown, the light spots obtained from multiple measuring holes are sorted according to their coordinate positions, thus obtaining the sorting between the two measuring light spots 8 and the measured film hole 4 on the turbine blade 2.

[0069] S63. Identify the location of the light spot with the highest light intensity and call the light spot part corresponding to this location the maximum light intensity area 9. For each measured hole, there are two maximum light intensity areas 9.

[0070] S64. Locate the center point of the region with the highest light intensity, 9.

[0071] S65, such as Figure 5 As shown, the vector line formed by connecting the two center points of the same air film pore being measured is the center line 10 of the pore. The angle between the center line 10 and the x and y axes can be calculated to obtain the angle of the air film pore 4 being measured.

[0072] S66. Connect the two maximum light intensity regions of the same air film aperture 4 to form a cylinder 11, and calculate the diameter of the cylinder 11, which is the diameter of the air film aperture 4 to be measured.

[0073] Based on the above measurement method, this application also provides a non-contact turbine blade film pore diameter measurement system, which includes:

[0074] A micro light source 1 is disposed in the inner cavity of the turbine blade to generate a light beam that passes through the film gas aperture;

[0075] Receiver plate 3, disposed on the outer side of the inner cavity of the turbine blade, is used to receive the light beam generated by the miniature light source 1; and

[0076] A light-sensing system, connected to receiver 3, is used to convert the light signal received by receiver 3 into an electrical signal, and to obtain the position, shape and intensity of the strongest light beam received by receiver 3.

[0077] The data processing device calculates the angle and diameter of the measured air film aperture based on the position, shape, and intensity of the strongest beam.

[0078] The non-contact turbine blade film pore diameter measurement method and system provided in this application can improve the measurement speed of film pores and can be used in multi-unit assembly mode. The measurement process is simple and the measurement accuracy is high.

[0079] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A non-contact turbine blade film hole diameter measurement method, characterized by, The method includes: A tiny light source is inserted into the inner cavity of the turbine blade, and a receiving plate is placed on the outside of the inner cavity of the turbine blade. A tiny light source is controlled to generate a light beam, which passes through the film aperture of the turbine blade and forms an image on a receiving plate. This allows the position, shape, and intensity of the light beam at a first angle to be obtained between the receiving plate and the turbine blade. The receiving plate is connected to a light-sensing system, which converts the light signal received by the receiving plate into an electrical signal, thereby enabling the detection and imaging of the position, shape, and intensity of the light beam. Adjust the angle and position of the receiving plate relative to the turbine blade, and repeat the above process to obtain the beam position, shape and intensity of the beam between the receiving plate and the turbine blade at the second angle; The angle and diameter of the air film aperture are obtained based on the beam position, shape, and intensity at the first angle and the beam position, shape, and intensity at the second angle. The process is as follows: Calculate the maximum light intensity at each coordinate point of the multiple air film holes obtained on the receiving plate during the same measurement period; The light spots obtained from multiple measurement holes at coordinate positions are sorted to obtain the order between the two measurement light spots and the measured film air holes on the turbine blade. The location of the largest spot in the beam is identified to obtain the maximum light intensity region. For each measured aperture, there are two maximum light intensity regions. Find the center point of the maximum light intensity zone, connect the two center points of the maximum light intensity zones of the same air film aperture, and the vector line formed is the center line of the air film aperture. Calculate the angle between the center line and the x and y axes, and you will get the angle of the air film aperture. Connect the two regions with the highest light intensity of the same air film pore to form a cylinder, and calculate the diameter of the cylinder to obtain the diameter of the air film pore.

2. The non-contact turbine blade film hole diameter measurement method of claim 1, wherein, The tiny light source is connected to an extension rod, which is used to control the movement of the tiny light source within the turbine blade cavity.

3. The non-contact turbine blade film hole diameter measurement method of claim 1, wherein, If the receiving plate cannot directly receive the light spot due to mutual obstruction between adjacent turbine blades, at least one plane mirror can be placed between the turbine blade and the receiving plate, and the angle between the plane mirror and the air film aperture can be adjusted so that the receiving plate can receive the light beam reflected from the plane mirror.

4. A system for implementing the non-contact turbine blade film pore diameter measurement method according to any one of claims 1 to 3, the system comprising: A micro-light source is disposed inside the turbine blade to generate a light beam that passes through the film gas aperture; A receiving plate, located on the outer side of the inner cavity of the turbine blade, is used to receive the light beam generated by a tiny light source. The light-sensing system, connected to the receiving board, is used to convert the light signal received by the receiving board into an electrical signal, and to obtain the detection and imaging of the position, shape and intensity of the strongest light beam received by the receiving board. The data processing device calculates the angle and diameter of the measured air film aperture based on the position, shape, and intensity of the strongest light beam. The calculation process is as follows: Calculate the maximum light intensity at each coordinate point of the multiple air film holes obtained on the receiving plate during the same measurement period; The light spots obtained from multiple measuring holes at coordinate positions are sorted to obtain the order between the two measuring light spots and the measured film air holes on the turbine blade. The location of the largest spot in the beam is identified to obtain the maximum light intensity region. For each measured aperture, there are two maximum light intensity regions. Find the center point of the maximum light intensity zone, connect the two center points of the maximum light intensity zones of the same air film aperture, and the vector line formed is the center line of the air film aperture. Calculate the angle between the center line and the x and y axes, and you will get the angle of the air film aperture. Connect the two regions with the highest light intensity of the same air film pore to form a cylinder, and calculate the diameter of the cylinder to obtain the diameter of the air film pore.

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