CN116735044A - Cascade leaf top global steady-state pressure measurement method and device - Google Patents
Cascade leaf top global steady-state pressure measurement method and device Download PDFInfo
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- 238000000034 method Methods 0.000 title claims abstract description 66
- 238000009530 blood pressure measurement Methods 0.000 title claims abstract description 28
- 239000003973 paint Substances 0.000 claims abstract description 42
- 238000005259 measurement Methods 0.000 claims abstract description 24
- 230000003287 optical effect Effects 0.000 claims description 40
- 230000005284 excitation Effects 0.000 claims description 22
- 239000011248 coating agent Substances 0.000 claims description 13
- 238000000576 coating method Methods 0.000 claims description 13
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- 238000012935 Averaging Methods 0.000 claims description 4
- 230000008859 change Effects 0.000 claims description 3
- 238000004891 communication Methods 0.000 claims description 3
- 238000005507 spraying Methods 0.000 claims description 3
- 230000006641 stabilisation Effects 0.000 claims description 2
- 238000011105 stabilization Methods 0.000 claims description 2
- 238000000691 measurement method Methods 0.000 abstract description 8
- 230000008901 benefit Effects 0.000 abstract description 6
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- 230000005281 excited state Effects 0.000 description 5
- 238000002474 experimental method Methods 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 4
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- 238000013461 design Methods 0.000 description 3
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- 229910052760 oxygen Inorganic materials 0.000 description 3
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- 230000009286 beneficial effect Effects 0.000 description 2
- 238000007664 blowing Methods 0.000 description 2
- 230000001419 dependent effect Effects 0.000 description 2
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/24—Measuring force or stress, in general by measuring variations of optical properties of material when it is stressed, e.g. by photoelastic stress analysis using infrared, visible light, ultraviolet
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
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Abstract
The application relates to the field of aeroengines, in particular to a cascade blade top global steady-state pressure measurement method and device. First, the paint used is calibrated, and after the paint calibration is completed, the measurement of the blade grid and blade top area is started. The method has no damage to the measured model, and has unique advantages compared with the traditional pressure measurement method, which indicates that the measurement method of the global steady-state pressure in the clearance area of the blade cascade blade tip is realized. The pressure measuring method can solve the problem that the traditional pressure measuring method damages a measured model and the problem that the measuring result is limited to a limited discrete point. Experimental results show that the pressure information on discrete points is obtained by the traditional pressure measurement method, the global steady-state pressure distribution information can be obtained according to the measurement method, and the pressure information obtained by the traditional pressure measurement method are well matched.
Description
Technical Field
The application relates to the field of aeroengines, in particular to a method and a device for measuring global steady-state pressure of a blade top region on the top surface of a stationary blade cascade blade by applying optical pressure-sensitive paint.
Background
The impeller machine is a power machine which takes a continuous rotating blade as a main body and converts and transmits energy between a fluid medium and shaft power, and is closely related to our life. From fans, water turbines, water pumps and the like which are common in life to turbines, compressors and rotors in the aerospace field, the rotor blade belongs to the field of impeller machinery. One of the core components of power plants in the aerospace field is composed of an impeller machine. The planar cascade experiment plays an important role in the development of the design method of the advanced impeller machinery, and the pressure measurement of each part of the blade is the most important in the planar cascade experiment. In order to avoid friction between the blades and the casing in the compressor, a certain amount of blade tip clearance needs to be reserved at the blade tip in the design, part of gas can cross the blade tip under the action of pressure difference of front and rear suction pressure surfaces of the blade tip, a complex vortex structure is formed near the clearance area, loss is caused, and efficiency is reduced. Therefore, the perception of the flow field of the blade tip region has important significance for reducing the total loss of the compressor and improving the efficiency of the compressor.
In recent years, an optical pressure sensitive paint measurement technique (Pressure Sensitive Paint, PSP) based on computer vision and image processing techniques has received a great deal of attention. The PSP technique manometry principle is based on the oxygen quenching effect during photoluminescence. Under the illumination of ultraviolet rays with a certain wavelength, the paint molecules absorb light energy to reach a high-energy excited state from a ground state, the excited state is unstable, the energy obtained during excitation is easily lost, the excited state is deactivated, the deactivation process releases radiant light to the environment, when the excited state molecules meet oxygen molecules, the excited energy is transferred out, and the excited state molecules are deactivated to the ground state, the process does not emit fluorescence, and the concentration of the oxygen molecules under different pressures is different, so that the radiant light intensity of the paint molecules under illumination has a quantitative relation with the pressure, and can be described by a Stern-Volmer equation:
wherein A and B are constants dependent on temperature, which can be obtained by paint calibrationThe method comprises the steps of carrying out a first treatment on the surface of the I and I ref Respectively, real-time light intensity and reference light intensity, P and P ref Respectively a real-time pressure and a reference pressure.
The measurement technology can more intuitively and comprehensively reflect the global pressure distribution condition of the object surface. Conventional manometry measures through a series of static pressure holes along the blade surface, so the data is limited to a limited number of discrete points. In addition, because the area of the top area of the cascade blade is smaller, the resolution of the pressure field obtained by adopting the conventional pressure measurement method is extremely low, and the development requirement of the future fine design of the engine can not be met. One obvious advantage of PSP technology is that the pressure field across the blade can be determined. The method has the advantages of greatly reducing the complexity of measurement, compensating the damage of the arrangement pressure probe to the measured model and the interference of the flow field to be measured, along with no contact, quick measurement period, high spatial resolution, lower cost and the like.
In the prior art, a series of PSP measurement experiments are carried out aiming at a large-bend-angle diffusion blade cascade. And the experiment is carried out by spraying PSP on the suction surface of the large-bend diffusion blade grid, so that the global pressure measurement of the suction surface is completed. The application of PSP measurement technology on the surface of the blade cascade has been developed to be mature, and the PSP measurement technology cannot be directly used for blade top measurement due to the limitation of the blade top structure of the blade cascade, and the prior art lacks the fine pressure measurement research of the blade top area. At present, the research on the flow field of the clearance area of the top of the blade grid is concentrated on a numerical method, because the flow field of the clearance area of the top of the blade is complex, the space is narrow, the difficulty in experimental development is high, and the total pressure probe measurement method is adopted to open static pressure holes in the area of the top of the blade, the surface of the blade can be greatly influenced, the flow field of the clearance area is further influenced, and the measurement result is error.
Therefore, a method for performing a contactless measurement on the global steady-state pressure in the gap region is needed to solve the above-mentioned problems.
Disclosure of Invention
The purpose of the application is that: the application provides a method and a device for measuring global steady-state pressure of a blade top region of a stationary blade cascade based on optical pressure-sensitive coating, which aim to solve the problems that a measured model is damaged and a measurement result is limited to a limited number of discrete points when the global steady-state pressure of the blade top gap region of the blade cascade is measured by a traditional pressure measuring method. First, the paint used is calibrated, and after the paint calibration is completed, the measurement of the blade grid and blade top area is started. The method has no damage to the measured model, and has unique advantages compared with the traditional pressure measurement method, which indicates that the measurement method of the global steady-state pressure in the clearance area of the blade cascade blade tip is realized. The pressure measuring method can solve the problem that the traditional pressure measuring method damages a measured model and the problem that the measuring result is limited to a limited discrete point.
In order to achieve the above object, the present application provides a technical solution:
an optical pressure-sensitive coating-based cascade leaf top global steady-state pressure measurement method comprises the following method steps:
step 1: calibrating the optical pressure-sensitive paint;
step 2: measuring the area of the top of the cascade leaf:
step 2.1: uniformly spraying the optical pressure-sensitive coating calibrated in the step 1 on the tops of the cascade leaves;
step 2.2: adjusting the measuring device to ensure that clear PSP images of the blade tops of the blade cascades can be acquired;
step 2.3: turning off the light source, and collecting a group of dark background images;
step 2.4: starting a light source, collecting a group of images uniformly distributed on the surface pressure of the blade in the atmospheric pressure environment, and subtracting the dark background image in the step 2.3 to obtain a reference image;
step 2.5: adjusting total pressure to change incoming flow Mach numbers, collecting PSP images of blade tops of blade grids under different Mach numbers, and subtracting dark background images to obtain light intensity under corresponding Mach numbers;
step 2.6: calculating to obtain global steady-state pressure information of the blade tops of the cascade under different Mach numbers according to a formula (1);
wherein I is ref For reference image intensity, I is real-time intensityA and B are constants dependent on temperature, obtained by paint calibration, P and P ref Respectively a real-time pressure and a reference pressure.
The application further adopts the technical scheme that: the pressure measurement method further comprises the step 3 of:
changing attack angles, and repeating the steps 2.3-2.5 to obtain PSP images of the top of the cascade leaves under different attack angles; and (3) converting the obtained image into pressure distribution according to the S-V curve of the optical pressure-sensitive coating obtained by the calibration in the step (1).
The application further adopts the technical scheme that: the step 1 of calibrating the optical pressure-sensitive paint used comprises the following steps:
step 1.1: installing a sample wafer and arranging a light source position, so that light spots of the light source vertically irradiate the surface of the PSP sample wafer to be tested, arranging a camera to vertically shoot the PSP sample wafer, adjusting the aperture of the camera and the exposure time, and ensuring that the camera can acquire clear PSP sample wafer images;
step 1.2: setting the temperature and pressure in the calibration cabin as preset values, keeping all equipment parameters unchanged in a dark environment, and collecting a group of dark background images;
step 1.3: turning on an LED light source, and collecting a PSP image as a calibrated reference image;
step 1.4: setting an initial temperature T 0 And an initial pressure P 0 Collecting a group of luminous images of the PSP sample after stabilization, and regulating the pressure to P according to the pressure step delta P max Collecting PSP images under all set pressures;
step 1.5: according to the temperature step length delta T, the temperature is regulated, PSP images under different pressures at each set temperature are collected until the temperature reaches T max ；
Step 1.6: averaging PSP images acquired under each working condition to obtain an averaged image minus a dark background image;
step 1.7: substituting the light intensity ratio and the pressure ratio into the formula (1) to obtain corresponding A and B values, and completing calibration.
The application further adopts the technical scheme that: the step 2.1 also comprises the step of setting mark points on the tested surface blade sprayed with the optical pressure-sensitive coating for image alignment.
The application further adopts the technical scheme that: the specific process of the step 2.2 is as follows:
the excitation light source is fixed through the tripod, the camera is arranged on a five-dimensional mechanism of the optical platform, 3 directions and 2 angles are moved or rotated, the camera is enabled to completely shoot the leaf tops, and the leaf tops are evenly irradiated by the excitation light source.
The application further adopts the technical scheme that: in the step 2.5, the cascade wind tunnel is started to adjust the incoming flow to the Mach number of the incoming flow in the set state.
The other technical scheme provided by the application is as follows:
an apparatus for implementing the pressure measurement method, comprising: image acquisition device, auxiliary device and computer:
the image acquisition equipment comprises an excitation light source, an optical filter and a CCD camera, wherein the light path of the excitation light source, the optical filter and the CCD camera are sequentially connected, the excitation light source is fixed on a tripod, the CCD camera is arranged on a five-dimensional displacement mechanism, and the tripod and the five-dimensional displacement mechanism are both positioned on an optical platform;
the auxiliary equipment comprises a laser level meter, a laser distance meter and a pressure sensitive paint thickness meter; accurately determining the space three-dimensional coordinate position between the excitation light source and the CCD camera through a laser level meter and a laser range finder; the pressure sensitive paint thickness gauge is used for paint thickness measurement;
the image acquisition equipment and the auxiliary equipment are both in communication connection with the computer.
The beneficial effects are that:
compared with the prior art, the application has the beneficial effects that:
(1) The application provides a cascade leaf top global steady-state pressure measurement method and device based on optical pressure-sensitive paint, which are used for measuring the pressure of a cascade leaf top gap area through the pressure-sensitive paint, have no damage to a measured model and have unique advantages compared with the traditional pressure measurement method.
(2) The application provides a cascade blade top global steady-state pressure measurement method and device based on optical pressure-sensitive paint, which can measure global pressure information of the blade top surface through the pressure-sensitive paint, so that measurement data is not limited to a limited number of discrete points.
(3) The application provides a method and a device for measuring global steady-state pressure of top areas of cascade vanes based on optical pressure-sensitive coating, and the experimental result of fig. 3 shows that the pressure information on discrete points is obtained by the traditional pressure measuring method, and the global steady-state pressure distribution information can be obtained by the measuring method according to the application, and the pressure information obtained by the two methods is better in agreement.
Drawings
FIG. 1 is a schematic view of a calibration test stand of the present application;
FIG. 2 is a schematic diagram of a measurement test stand;
FIG. 3 is a comparative graph of the analysis of the measurement results of the present application.
Reference numerals in the drawings denote:
1-cascade inlet; 2-leaf grating; 3-an excitation light source; 4-an optical filter; 5-a CCD camera; 6-tripod; 7-a displacement mechanism; 8-an optical platform.
Detailed Description
The present application will be described in further detail with reference to the following specific examples, which should not be construed as limiting the application in any way.
Example 1
A method for measuring the global steady-state pressure of the top of a cascade of leaves based on optical pressure-sensitive paint adopts a light intensity method to measure the pressure value,
first, the paint used is calibrated as follows:
step 1: and installing the sample wafer and arranging the position of the light source so that the light spot of the light source irradiates the surface of the PSP sample wafer to be measured as perpendicularly as possible. Arranging the camera position so that the camera shoots the PSP sample as vertically as possible; and adjusting the aperture and the exposure time of the camera to ensure that the camera can acquire clear PSP images.
Step 2: setting the temperature and pressure in the calibration cabin as preset values, keeping all other equipment parameters unchanged in a dark environment, and collecting a group of dark background images.
Step 3: the LED light source is turned on, and a set of luminous images of the PSP test piece are collected as a calibrated reference image Iref.
Step 4: setting an initial temperature T0 and an initial pressure P0, collecting a group of luminous images of PSP sample wafers after the PSP sample wafers are stabilized, adjusting the pressure to Pmax according to the pressure step delta P, and collecting PSP luminous images under all the set pressures.
Step 5: and regulating the temperature according to the temperature step delta T, and acquiring PSP images under different pressures at each set temperature until the temperature reaches Tmax.
Step 6: and averaging the PSP images acquired under each working condition to obtain an averaged image minus a dark background image so as to remove the influence of the environment on the measurement result.
Step 7: substituting the light intensity ratio and the pressure ratio into a Stern-Volmer formula to obtain corresponding A and B values.
Through the steps, the calibration of the paint is completed.
Next, measurement of the tip region of the cascade was started, which was as follows:
step 1: and after the heat treatment is carried out on the blade cascade, coating is sprayed on the blade tops, so that the coating is ensured to be uniformly sprayed and thin, and the interference on a flow field is ensured to be negligible.
Step 2: the position, aperture and exposure time of the camera are adjusted, the orthogonality between the camera and the top surface of the leaf is increased as much as possible, and the camera can accurately acquire clear PSP images.
Step 3: the light source is turned off and a group of pictures is photographed as a dark background image.
Step 4: and (3) turning on a light source, uniformly distributing the surface pressure of the blade in the atmospheric pressure environment, turning on the light source to shoot a group of pictures, and subtracting a dark background image from the group of pictures to serve as a reference image.
Step 5: and adjusting the total pressure to change the Mach number of the incoming flow, shooting PSP images of the tops of the cascade leaves under different Mach numbers, and subtracting the dark background images to obtain the light intensity under the current Mach number.
Step 6: and calculating global steady-state pressure information of blade tops of the cascade vanes under different Mach numbers according to a Stern-Volmer formula of an optical pressure-sensitive coating pressure measuring principle.
The measurement process is carried out in a cascade wind tunnel, pressure sensitive paint is sprayed on the top area of the cascade, PSP images of the pressure sensitive paint under different Mach numbers are shot, and the pressure distribution on the top surface of the cascade can be obtained after data processing through the calibrated PSP characteristic curve.
Example 2
The application also provides a global pressure measuring system for the top surface of the cascade blade, which comprises the following components: image acquisition device, auxiliary device and computer: the image acquisition equipment comprises an excitation light source 3, an optical filter 4 and a CCD camera 5, wherein the light paths of the excitation light source 3, the optical filter 4 and the CCD camera 5 are sequentially connected, the excitation light source 3 is fixed on a tripod 6, the CCD camera 5 is arranged on a five-dimensional displacement mechanism 7, and the tripod 6 and the five-dimensional displacement mechanism 7 are both positioned on an optical platform 8;
the auxiliary equipment comprises a laser level meter, a laser distance meter and a pressure sensitive paint thickness meter; accurately determining the space three-dimensional coordinate position between the excitation light source 3 and the CCD camera 5 through a laser level meter and a laser range finder; the pressure sensitive paint thickness gauge is used for paint thickness measurement; the image acquisition equipment and the auxiliary equipment are both in communication connection with the computer.
Wherein the optical platform 8 is used for placing optical elements to block vibration; the excitation light source 3 adopts an LED array light source; a filter 4 is installed in front of the CCD camera 5 to block light other than the fluorescence wavelength of the paint from being captured by the camera.
The implementation process of the designed cascade blade top surface global steady-state pressure measurement method based on the light intensity method is realized by means of the measurement system specifically comprises the following steps:
1. a pre-calibrated coating is sprayed onto the top surface of the cascade leaf. Because vibration in the wind tunnel operation process can cause the position of the blade to deviate, the reference image and the blowing image cannot be aligned, and in order to eliminate the vibration, mark points are required to be arranged on the measured surface for image alignment.
2. The excitation light source 3 is fixed by a tripod 6, and in order to attenuate the image shift of the CCD camera 5 due to the ground vibration, the camera is mounted on a five-dimensional mechanism of an optical platform 8 to achieve 3-direction and 2-angle movements or rotations. The tripod 6 and the five-dimensional mechanism are adjusted, the camera can completely shoot the top of the leaf according to reasonable light path layout, and the excitation light source 3 uniformly irradiates the top of the leaf.
3. The geometric center of the blade to be measured of the blade grid is used as the origin of coordinates, and the excitation light source 3 and the CCD camera 5 are positioned by means of a laser level meter and a laser range finder.
4. According to the optical pressure-sensitive measurement principle, the light source is turned off, and a set of dark background images under a set attack angle are acquired and averaged in a windless state.
5. The light source is turned on, and a set of reference images is acquired and averaged in a windless state.
6. And starting the cascade wind tunnel to adjust the incoming flow to the Mach number of the incoming flow in a set state, and starting the light source to collect a group of blowing images in the incoming flow state and averaging after the state is stable.
7. Repeating steps 4-6 by changing attack angles to obtain optical pressure-sensitive images of top surfaces of cascade leaves under different attack angles
8. The resulting image is converted into a pressure distribution according to the calibrated S-V curve of the optical pressure sensitive coating.
The calibration method comprises the following steps: placing a sample wafer coated with PSP paint in a pressure-adjustable cabin body, and adjusting the pressure in the cabin to P 1 The luminous image I of the paint at the moment is acquired by a camera c The method comprises the steps of carrying out a first treatment on the surface of the Regulating the pressure P in the cabin for multiple times, and capturing a corresponding luminous image I through a camera; bringing the data acquired multiple times into a calibration formula
And forming a binary primary equation set, wherein variables are A and B, and calculating to obtain A and B to obtain calibration parameters.
FIG. 3 is a graph comparing PSP measurement method with traditional pressure measuring hole experiment method under attack angle of-2.5 deg., wherein Tap refers to pressure measuring hole measurement method, PSP refers to measurement method in the present application, SS refers to blade suction surface, and PS refers to blade pressure surface. It can be seen that the pressure information on discrete points is obtained by the conventional pressure measuring method, and the global steady-state pressure distribution information can be obtained by the measuring method according to the application, and the pressure information obtained by the two methods is better matched.
The application provides a cascade leaf top global steady-state pressure measurement method and device based on optical pressure-sensitive paint, which are used for measuring the pressure of a cascade leaf top gap area through the pressure-sensitive paint, have no damage to a measured model and have unique advantages compared with the traditional pressure measurement method; the global pressure information of the top surface of the blade can be measured by means of the pressure sensitive paint, so that the measurement data is no longer limited to a limited number of discrete points. Experimental results show that the pressure information on discrete points is obtained by the traditional pressure measuring method, the global steady-state pressure distribution information can be obtained by the measuring method, and the pressure information obtained by the traditional pressure measuring method are well matched.
Although embodiments of the present application have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the application, and that variations, modifications, alternatives, and variations may be made in the above embodiments by those skilled in the art without departing from the spirit and principles of the application.
Claims (7)
1. A cascade leaf top global steady-state pressure measurement method based on optical pressure-sensitive paint is characterized by comprising the following steps of: the method comprises the following steps:
step 1: calibrating the optical pressure-sensitive paint;
step 2: measuring the area of the top of the cascade leaf:
step 2.1: uniformly spraying the optical pressure-sensitive coating calibrated in the step 1 on the tops of the cascade leaves;
step 2.2: adjusting the measuring device to ensure that clear PSP images of the blade tops of the blade cascades can be acquired;
step 2.3: turning off the light source, and collecting a group of dark background images;
step 2.4: starting a light source, collecting a group of images uniformly distributed on the surface pressure of the blade in the atmospheric pressure environment, and subtracting the dark background image in the step 2.3 to obtain a reference image;
step 2.5: adjusting total pressure to change incoming flow Mach numbers, collecting PSP images of blade tops of blade grids under different Mach numbers, and subtracting dark background images to obtain light intensity under corresponding Mach numbers;
step 2.6: calculating to obtain global steady-state pressure information of the blade tops of the cascade under different Mach numbers according to a formula (1);
wherein I is ref For reference image intensity, I is the real-time intensity, A and B are constants related to temperature, obtained by paint calibration, P and P ref Respectively a real-time pressure and a reference pressure.
2. The pressure measurement method according to claim 1, wherein: the pressure measurement method further comprises the step 3 of:
changing attack angles, and repeating the steps 2.3-2.5 to obtain PSP images of the top of the cascade leaves under different attack angles; and (3) converting the obtained image into pressure distribution according to the optical pressure-sensitive paint curve obtained by the calibration in the step (1).
3. The pressure measurement method according to claim 2, wherein: the step 1 of calibrating the optical pressure-sensitive paint used comprises the following steps:
step 1.1: installing a sample wafer and arranging a light source position, so that light spots of the light source vertically irradiate the surface of the PSP sample wafer to be tested, arranging a camera to vertically shoot the PSP sample wafer, adjusting the aperture of the camera and the exposure time, and ensuring that the camera can acquire clear PSP sample wafer images;
step 1.2: setting the temperature and pressure in the calibration cabin as preset values, keeping all equipment parameters unchanged in a dark environment, and collecting a group of dark background images;
step 1.3: turning on an LED light source, and collecting a PSP image as a calibrated reference image;
step 1.4: setting an initial temperature T 0 And an initial pressure P 0 Collecting a group of luminous images of the PSP sample after stabilization, and regulating the pressure to be the pressure step delta PP max Collecting PSP images under all set pressures;
step 1.5: according to the temperature step length delta T, the temperature is regulated, PSP images under different pressures at each set temperature are collected until the temperature reaches T max ；
Step 1.6: averaging PSP images acquired under each working condition to obtain an averaged image minus a dark background image;
step 1.7: substituting the light intensity ratio and the pressure ratio into the formula (1) to obtain corresponding A and B values, and completing calibration.
4. The pressure measurement method according to claim 2, wherein: the step 2.1 also comprises the step of setting mark points on the tested surface blade sprayed with the optical pressure-sensitive coating for image alignment.
5. The pressure measurement method according to claim 1, wherein: the specific process of the step 2.2 is as follows:
the excitation light source is fixed through the tripod, the camera is arranged on a five-dimensional mechanism of the optical platform, 3 directions and 2 angles are moved or rotated, the camera is enabled to completely shoot the leaf tops, and the leaf tops are evenly irradiated by the excitation light source.
6. The pressure measurement method of claim 5, wherein: in the step 2.5, the cascade wind tunnel is started to adjust the incoming flow to the Mach number of the incoming flow in the set state.
7. An apparatus for carrying out the pressure measurement method of any one of claims 1-6, characterized in that: the device comprises: image acquisition device, auxiliary device and computer:
the image acquisition equipment comprises an excitation light source, an optical filter and a CCD camera, wherein the light path of the excitation light source, the optical filter and the CCD camera are sequentially connected, the excitation light source is fixed on a tripod, the CCD camera is arranged on a five-dimensional displacement mechanism, and the tripod and the five-dimensional displacement mechanism are both positioned on an optical platform;
the auxiliary equipment comprises a laser level meter, a laser distance meter and a pressure sensitive paint thickness meter; accurately determining the space three-dimensional coordinate position between the excitation light source and the CCD camera through a laser level meter and a laser range finder; the pressure sensitive paint thickness gauge is used for paint thickness measurement;
the image acquisition equipment and the auxiliary equipment are both in communication connection with the computer.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117288570A (en) * | 2023-11-27 | 2023-12-26 | 深圳三思纵横科技股份有限公司 | Automatic overpressure control method and system based on pressure testing machine |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117288570A (en) * | 2023-11-27 | 2023-12-26 | 深圳三思纵横科技股份有限公司 | Automatic overpressure control method and system based on pressure testing machine |
| CN117288570B (en) * | 2023-11-27 | 2024-02-09 | 深圳三思纵横科技股份有限公司 | Automatic overpressure control method and system based on pressure testing machine |
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