CN115165962A - Thermal property measuring method and device of thermal insulation coating - Google Patents
Thermal property measuring method and device of thermal insulation coating Download PDFInfo
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Abstract
The invention relates to a method and a device for measuring the thermophysical property of a thermal insulation coating, which comprises a laser and a control device thereof, an infrared thermal imaging device, a temperature measuring device and a data receiving and processing device, and realizes the measurement of the material property with extremely low heat conductivity coefficient. The method comprises the steps of obtaining a temperature distribution graph through an infrared imaging technology, dividing the heat insulation coating into a preset number of infinitesimal areas according to the size of the geometric dimension corresponding to pixel points in the temperature distribution graph, establishing a steady-state and transient heat balance equation, correcting radiation heat exchange and convection heat exchange according to the temperature values of different infinitesimal areas, and solving the heat conductivity coefficient and the thermal diffusivity coefficient of the real-time heat insulation coating. The measuring device provided by the invention can be used for researching the physical properties of materials with extremely low thermal conductivity coefficients under different scales, thicknesses and temperature levels; the measurement result is obtained by the cooperative fitting of transient response and steady-state response of the material temperature rise, the cooperative measurement ensures high measurement precision, and the effective measurement of the material physical property with extremely low thermal conductivity is realized.
Description
Technical Field
The invention belongs to the technical field of thermophysical property measurement, and particularly relates to a thermophysical property measurement method and device of a thermal insulation coating.
Background
The heat insulation coating utilizes the excellent high temperature resistance, corrosion resistance, abrasion resistance, heat insulation and other properties of the ceramic material, so that the heat insulation coating is compounded with the substrate in a coating form to improve the high temperature corrosion resistance of the structural member, and is widely applied to the steam turbine blades, shells, turbine blades and other instruments needing heat insulation. The low thermal conductivity of the ceramic coating material can perfectly meet the requirements of heat insulation and reduction of the surface temperature of a workpiece, and the high temperature resistance of the metal and other matrixes of the blade is remarkably improved, so that the working temperature is improved. Meanwhile, the metal base body of the blade can be heated uniformly, the temperature gradient is small, and the service life and the reliability of the base body are greatly prolonged. Therefore, the thermal properties of the thermal insulation coating material, such as thermal conductivity coefficient and diffusion coefficient, play an extremely important role in the thermal insulation effect of the coating. However, due to the differences in the preparation method and process of the coating, the properties and surface appearance of the substrate material, and the thickness of the coating, the physical properties of the thermal insulation coating on the substrate are different, and the thermal insulation effect in practical application is greatly different from the theoretical expectation. In addition, the physical property measurement of materials with extremely low thermal conductivity (the thermal conductivity of the thermal insulation coating is far lower than that of air) is always a difficult problem, the laboratory measurement needs harsh conditions such as vacuum measurement, and the like, and the actual measurement needs to consider the influences such as convection radiation and the like. Therefore, a method and a device capable of measuring the thermophysical property of the thermal insulation coating with extremely low thermal conductivity coefficient in real time and without damage are particularly important.
Infrared imaging uses optoelectronic devices to detect and measure radiation and to correlate the radiation with surface temperature. A technique for receiving the radiant energy emitted by an object and thereby inferring its temperature. Patent No. CN111220647A discloses a non-contact nondestructive testing method and device for the heat insulation temperature of a heat insulation coating, which simulate a real service environment, heat the surface of a ceramic layer of the heat insulation coating through high-temperature high-speed flame flow heating, and measure the temperatures of the ceramic top layer and the back surface of the ceramic layer of a high-temperature alloy component with the heat insulation coating by using an infrared thermometer. Compared with the existing thermocouple contact temperature testing technology, the method has the advantages of non-contact measurement, no influence on the surface of the heat-insulating coating and the original gas flow field and temperature field in the hollow blade air passage, and simple testing process, but the method heats through high-temperature flame flow, has a large heating area, cannot realize controllable heating area, has long time for reaching thermal stability, is suitable for laboratory measurement, and is difficult to measure in a real-time manner. In addition, the method only simply measures the temperature of the upper surface and the lower surface of the coating, does not deeply measure the thermophysical property of the heat-insulating coating, and does not measure parameters capable of representing the physical property of the material. The patent number CN113588709A discloses a method for evaluating and predicting the heat insulation effect of a turbine blade heat insulation coating, which relates to the technical field of engines and solves the problem that the evaluation and prediction of the heat insulation effect of the coating are difficult to realize. The technology realizes accurate prediction of the heat insulation effect, but the heat insulation effect is essentially dependent on the thermophysical property, particularly the heat conductivity coefficient, of the heat insulation coating material, and the technology does not directly obtain the physical property parameters of the material.
Disclosure of Invention
The invention aims to provide a thermal property measurement method and a device of a thermal insulation coating aiming at the defects of the prior art, the measurement device is simple, the material (far lower than air) property measurement with extremely low heat conductivity coefficient is realized, the single-side nondestructive measurement of the thermal insulation coating can be carried out, the real-time measurement can be carried out, and the measurement result is accurate.
In order to solve the technical problem, the invention adopts the following technical scheme:
a thermal property measurement method of a thermal barrier coating, comprising the steps of:
s1, placing the thermal insulation coating at an outer probe of the measuring device, and selecting proper laser spot size and laser power according to the thickness of the thermal insulation coating, so that thermal waves cannot penetrate through the coating to meet a semi-infinite model.
S2, heating a thermal insulation coating sample by using continuous laser with proper spot size and laser power, and obtaining a temperature distribution diagram of the sample in the whole process from the beginning of heating to the steady state through an infrared camera;
s3, processing the infrared thermal image through a data collection computer to obtain a temperature distribution map, dividing the thermal insulation coating into a preset number of micro-element areas according to the size of the geometric dimension corresponding to a pixel point in the temperature distribution map, and extracting temperature values of different micro-element areas, wherein the number of the divided micro-element areas is the same as the number of the pixel points of the temperature distribution map;
s4, establishing a steady-state and transient-state heat balance equation, correcting radiation heat exchange and convection heat exchange according to temperature values of different micro elements, calculating the transient-state and steady-state changes of the micro element temperature according to the geometric size and laser power distribution of the micro element region and by combining numerical values, and solving the heat conductivity coefficient and the heat diffusion coefficient of the real-time heat insulation coating.
Further, in step S4, the established transient process:
the established steady state process:
Φ m+1 +Φ m-1 +Φ n+1 +Φ n-1 +Φ l+1 +Φ l-1 +PΔcΔyΔz＝Φ h +Φ r
wherein: phi (phi) of m+1 Represents the heat quantity of the micro element flowing in the positive direction of x due to heat conduction; phi m-1 Represents the heat of the micro element flowing in the negative direction of x due to heat conduction; phi (phi) of n+1 Represents the heat quantity of the micro element flowing in the positive direction of y due to heat conduction; phi n-1 Represents the heat of the micro-element flowing in the negative direction of y due to heat conduction; phi (phi) of l+1 Represents the heat of the micro element in the positive direction of z due to heat conduction; phi (phi) of l-1 Representing the heat in the negative z direction of the element due to heat conduction.
Further, the air conditioner is provided with a fan,
wherein Δ x, Δ y and Δ z represent the lengths of the micro-elements in the x, y and z directions, respectively, λ represents the thermal conductivity of the micro-elements, and T represents the thermal conductivity of the micro-elements (m+1,n,l) And T (m-1,n,l) Respectively represents the temperature of the front and back units of the infinitesimal in the x direction, T (m,n+1,l) And T (m,n-1,l) Respectively representing the temperature of the front unit and the rear unit of the infinitesimal in the y direction; t is (m,n,l+1) And T (m,n,l-1) Respectively representing the temperature of two units before and after the infinitesimal in the z direction;
p deltax deltay deltaz represents the amount of heat that the laser heats up flowing into the element,
where P is the laser incident intensity, τ L Is the laser absorption depth, r 0 Is the size of the laser spot, r is the distance from the center line of the laser spot, z is the distance from the outer surface of the coating, P 0 Out-of-spot P =0 for average power density;
Φ h ＝h(T (m,n,l) -T 0 ) Deltax Deltay represents the convective heat transfer of material surface microelements to the surrounding environment, where h is the sample surface to sample surfaceCoefficient of heat transfer by flow, T (m,n,l) Temperature, T, of the infinitesimal 0 Is the ambient temperature; because the convective heat transfer process only occurs on the surface of the material and in the interior of the material h ＝0；
Based on the same inventive concept, a second aspect of the present invention provides a measuring apparatus applied to the method of the first aspect, the apparatus comprising: the system comprises a laser connected with a laser controller, an infrared camera facing a heat insulation coating, a data processing module connected with the infrared camera, a thermocouple probe in contact with the coating, a thermocouple temperature measuring instrument, a convex lens controlled by a single-axis displacement platform, a shell and a data collecting computer, wherein the shell is used for accommodating the laser controller and the infrared camera;
the laser, the convex lens and the sample are kept in the same optical path and are arranged at the bottom of the shell. The infrared imager comprises an optical lens and an infrared imager host, and is arranged at the bottom of the shell.
Furthermore, the angle between the incident light path of the laser and the detection light path of the thermal infrared imager is less than or equal to 30 degrees.
Further, the thermal barrier coating thickness may be 10 micrometers to 10 millimeters.
Furthermore, the single-axis displacement platform controls the convex lens to move along the light path in a single axis manner, so that the size of the laser spot can be adjusted.
Further, a thermal conductivity of 10 can be achieved -3 The material properties of W/(m × k) are effectively measured.
Further, a thermocouple probe in contact with the coating transmits a temperature signal of the surface of the coating to a thermocouple temperature measuring instrument, and further transmits the temperature signal to a data collecting computer to realize surface emissivity correction of the thermal insulation coating.
One or more technical solutions of the present application at least have one or more of the following technical effects:
on the one hand, the method and the device for measuring the thermal physical property of the thermal insulation coating realize the physical property measurement of a material with extremely low thermal conductivity coefficient (far lower than air). Selecting proper laser spot size and laser power according to the thickness of the thermal insulation coating, processing an infrared thermal image shot by an infrared imager host through a data collection computer to obtain a temperature distribution diagram, dividing the thermal insulation coating into a preset number of infinitesimal areas according to the size of the geometric dimension corresponding to pixel points in the temperature distribution diagram, and extracting temperature values of different infinitesimal areas; establishing a steady-state and transient-state heat balance equation, correcting radiation heat exchange and convection heat exchange according to temperature values of different infinitesimals, calculating infinitesimal temperature transient and steady-state changes according to the geometric dimension and laser power distribution of the infinitesimal area and combining numerical values, and solving the heat conductivity coefficient and the heat diffusion coefficient of the real-time heat-insulating coating; the conductive filament is divided into the micro-element areas with the preset number according to the size of the geometric dimension corresponding to the pixel points in the temperature distribution diagram, and the temperature values of different micro-element areas are extracted, so that the accuracy and precision of measurement can be improved.
On the other hand, the measuring device provided by the invention can measure coating materials with different thicknesses, and meanwhile, the power of laser and the size of a laser spot can be adjusted, so that the physical properties of materials with extremely low thermal conductivity coefficients under different scales, different thicknesses and different temperature levels are researched; the device belongs to non-contact measurement, does not damage the surface structure and surface characteristics of the material in the measurement process, eliminates thermal contact resistance caused by contact, does not influence the heat exchange flow field with surrounding fluid, and can carry out on-site real-time measurement; the measurement result is obtained by the cooperative fitting of transient response and steady-state response of the temperature rise of the material, the transient measurement method can quickly obtain thermophysical parameters, the steady-state measurement method can ensure the accuracy of the measurement result, and the cooperative measurement ensures high measurement precision and good reliability; the measurement application range is wide, and the effective measurement of the physical properties of the material with extremely low thermal conductivity coefficient (far lower than air) is realized.
Drawings
FIG. 1 is a schematic structural view of a method and apparatus for measuring thermophysical properties of a thermal barrier coating;
FIG. 2 is a flow chart of a method and apparatus for measuring the thermophysical properties of a thermal barrier coating;
FIG. 3 is a thermal equilibrium analysis of steady state heat transfer in a laser spot in an embodiment of the invention.
FIG. 4 is a graph of thermal conductivity versus temperature rise for a thermal barrier coating as measured in an embodiment of the present invention.
FIG. 5 is a graph of thermal diffusivity versus temperature rise for a thermal barrier coating measured in accordance with an embodiment of the present invention.
In the figure: 1-a shell; 2-a laser; 3-a signal transmission line; 4-a laser controller; 5-a data collection computer; 6-thermocouple temperature measuring instrument; 7-uniaxial displacement stage; 8-thermocouple probe; 9-a substrate; 10-a thermal barrier coating; 11-convex lens; 12-infrared thermal imager host and lens.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
As shown in FIG. 1, the device for measuring the thermophysical property of the thermal barrier coating comprises a shell 1, a laser 2, a laser controller 4, an infrared thermal imaging device, a convex lens 11, a temperature measuring device and a data receiving and processing device. In the present embodiment, the housing 1 is used for mounting the laser 2, and the thermal infrared imager host and lens 12, the convex lens 11, and the single-axis displacement platform 7. In addition, the shell 1 can also play an effective dustproof role, and the influence of dust and the like in the air on laser signals is reduced. The laser controller 4 is connected with the laser 2 through the signal transmission line 3, and can adjust the laser 2 to generate laser with different power for heating the heat insulation coating 10 on the substrate 9, so that a proper temperature rise signal is ensured under the condition that the heat insulation coating 10 is not denatured. The convex lens 11, the laser 2 and the thermal insulation coating 10 are kept in the same optical path and are arranged on the single-axis displacement platform 7 and used for focusing laser; the single-axis displacement platform 7 is arranged on the bottom surface of the shell and comprises a mechanical sliding table and a guide rail, and the convex lens 11 is controlled to move back and forth on a light path, so that a proper laser spot size is generated on the coating.
The infrared thermal imaging device comprises a thermal infrared imager host and a lens 12 and is used for acquiring temperature information of the surface of the material to be measured. The infrared thermal imager is arranged on the bottom surface of the shell 1, and an included angle between a detection light path of the infrared thermal imager and a laser light path is not more than 30 degrees during installation. The temperature measuring device is used for correcting the surface emissivity of the heat-insulating coating 10 in the infrared temperature measurement process, and comprises a thermocouple temperature measuring instrument 6 and a thermocouple probe 8, wherein the thermocouple probe 8 is in direct contact with the coating. The data collection computer 5 is used in this embodiment to receive and process the electrical signals of the thermocouple thermometers 6 and the temperature signals of the micro element areas of the thermal infrared imager 12, and is electrically connected to the thermal infrared imager 12 and the thermocouple thermometers 6.
Before measurement, the surface emissivity of the thermal insulation coating 10 is measured, the thermocouple temperature measuring instrument 6 and the thermocouple probe 8 are used for measuring the temperature of the coating surface, and the internal parameters of the thermal infrared imager host and the lens 12 are adjusted: the surface emissivity is the real surface emissivity of the thermal barrier coating 10 until the surface temperature measured by the infrared camera is the same as the temperature measured by the thermocouple.
As shown in FIG. 2, the present invention also provides a method for measuring the thermal properties of a thermal barrier coating, comprising the following steps:
and (3) aligning the opening on the wall surface of the shell 1 with a point to be measured of the thermal insulation coating 10, so that laser is vertically irradiated on the surface of the coating. According to thermal barrier coating 10's thickness, adjust suitable laser facula size through unipolar displacement platform 7 control convex lens 5, through suitable laser power of laser controller 4 output for the thermal wave can't penetrate the coating, satisfies half infinite model, and measured thermal barrier coating 10 thickness can be 10 microns to 10 millimeters. After the infrared camera 12 is adjusted back and forth to complete focusing, the infrared camera is fixed and is in stable data connection with the data processing module (data collection computer 5).
Turning on laser, the laser 2 generates laser with proper power to heat the surface of the coating, and the temperature distribution diagram of the heat insulation coating in the whole process from the beginning to the steady state is obtained through the infrared camera 12;
processing the infrared thermal image through a data collection computer to obtain a temperature distribution diagram, dividing the thermal insulation coating into a preset number of micro-element areas according to the size of the geometric dimension corresponding to a pixel point in the temperature distribution diagram, and extracting temperature values of different micro-element areas, wherein the number of the divided micro-element areas is the same as the number of the pixel points of the temperature distribution diagram. The pixel point is adjustable from 5 to 50 microns;
and establishing a steady-state and transient-state heat balance equation, and solving the heat conductivity coefficient and the heat diffusion coefficient of the thermal insulation coating 10 at different temperatures.
For the infinitesimal thermal balance analysis in the laser spot in the steady-state three-dimensional heat transfer process, as shown in fig. 3, the thermal balance is:
Φ m+1 +Φ m-1 +Φ n+1 +Φ n-1 +Φ l+1 +Φ l-1 +PΔcΔyΔz＝Φ h +Φ r
wherein:
wherein Δ x, Δ y and Δ z represent the lengths of the micro-elements in the x, y and z directions, respectively, λ represents the thermal conductivity of the micro-elements, and T represents the thermal conductivity of the micro-elements (m+1,n,l) And T (m-1,n,l) Respectively representing the temperatures, T, of two units in front and behind the infinitesimal in the x direction (m,n+1,l) And T (m,n-1,l) Respectively representing the temperature of the front unit and the rear unit of the infinitesimal in the y direction; t is (m,n,l+1) And T (m,n,l-1) Respectively representing the temperature of two units before and after the infinitesimal in the z direction;
p deltax deltay deltaz represents the amount of heat that the laser heats up flowing into the element,
where P is the laser incident intensity, τ L Is the laser absorption depth, r 0 Is the size of the laser spot, r is the distance from the center line of the laser spot, z is the distance from the outer surface of the coating, P 0 Outside the spot for average power densityP＝0；
Φ h ＝h(T (m,n,l) -0) Deltax Deltay represents the convective heat transfer of the material surface infinitesimal with the surrounding environment, where h is the convective heat transfer coefficient of the sample surface, T (m,n,l) Temperature, T, of the infinitesimal 0 Is the ambient temperature; because the convective heat transfer process only occurs on the surface of the material and in the interior of the material h ＝0；
Similarly, the heat balance equation outside the three-dimensional steady-state heat transfer light spot is written as
Φ m+1 +Φ m-1 +Φ n+1 +Φ n-1 +Φ l+1 +Φ l-1 ＝Φ h +Φ r
Combining the above equation and the temperature values of the points, the thermal conductivity λ can be obtained
Similarly, the heat balance equation inside and outside the three-dimensional transient heat transfer light spot is as follows:
light spot internal infinitesimal:
light spot external infinitesimal:
wherein,
represents the change of internal energy of the infinitesimal element caused by the temperature rise within the time delta tau, wherein
And
respectively representing the temperature of the micro element at the moment and the previous moment, alpha represents the thermal diffusion coefficient of the thermal insulation coating material, and lambda represents the thermal conductivity coefficient of the micro element; and (3) calculating the solved thermal conductivity coefficient lambda by using a steady state numerical value, and solving the thermal diffusion coefficient alpha of the material by using a numerical calculation method according to a transient temperature change equation of the thermal insulation coating.
The embodiment provides a method and a device for measuring the thermophysical property of a thermal insulation coating. The device can measure coating materials with different thicknesses, and meanwhile, the laser power and the laser spot size can be adjusted, so that the physical properties of materials with extremely low thermal conductivity coefficients under different scales, different thicknesses and different temperature levels are researched; in the embodiment, the thickness of the ceramic thermal insulation coating is 220um, the laser wavelength is 532nm, the power is 5mW, and the spot size is 25um. Fig. 4 is a graph of the relationship between the thermal conductivity and the temperature rise of the ceramic thermal insulation coating, the average thermal conductivity of the ceramic thermal insulation coating under different temperature rises is 0.0085W/(m × k), and the effective measurement of the physical properties of the material with the extremely low thermal conductivity (far lower than that of air) is realized. FIG. 5 is a graph showing the relationship between the thermal diffusivity and the temperature rise of a thermal insulation ceramic coating, wherein the average thermal diffusivity of the thermal insulation ceramic coating at different temperatures is 4.33X 10 -7 m 2 And s. The device belongs to non-contact measurement, does not damage the surface structure and surface characteristics of the material in the measurement process, eliminates thermal contact resistance caused by contact, does not influence the heat exchange flow field with surrounding fluid, and can carry out on-site real-time measurement;
while preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.
It will be apparent to those skilled in the art that various modifications and variations can be made in the embodiments of the present invention without departing from the spirit or scope of the embodiments of the invention. Thus, if such modifications and variations of the embodiments of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to encompass these modifications and variations.
Claims (10)
1. A thermal property measurement method of a thermal insulation coating is characterized in that: comprises the following steps of (a) preparing a solution,
s1, placing a thermal insulation coating at an outer probe of a measuring device, and selecting proper laser spot size and laser power according to the thickness of the thermal insulation coating, so that thermal waves cannot penetrate through the coating and a semi-infinite model is met;
s2, heating a thermal insulation coating sample by using continuous laser with proper spot size and laser power, and obtaining a temperature distribution diagram of the sample in the whole process from the beginning of heating to the steady state through an infrared camera;
s3, processing the infrared thermal image through a data collection computer to obtain a temperature distribution map, dividing the thermal insulation coating into a preset number of micro-element areas according to the size of the geometric dimension corresponding to a pixel point in the temperature distribution map, and extracting temperature values of different micro-element areas, wherein the number of the divided micro-element areas is the same as the number of the pixel points of the temperature distribution map;
s4, establishing a steady-state and transient-state heat balance equation, correcting radiation heat exchange and convection heat exchange according to temperature values of different micro elements, calculating the transient-state and steady-state changes of the micro element temperature according to the geometric size and laser power distribution of the micro element region and by combining numerical values, and solving the heat conductivity coefficient and the heat diffusion coefficient of the real-time heat insulation coating.
2. The method for measuring the thermophysical property of a thermal barrier coating according to claim 1, wherein: in the step S4, the process is repeated,
the established transient process is as follows:
the established steady state process:
Φ m+1 +Φ m-1 +Φ n+1 +Φ n-1 +Φ l+1 +Φ l-1 +PΔxΔyΔz＝Φ h +Φ r
wherein: phi m+1 Represents the heat quantity of the micro element flowing in the positive direction of x due to heat conduction; phi m-1 Represents the heat of the micro element flowing in the negative direction of x due to heat conduction; phi n+1 Represents the heat of the micro element in the positive direction of y due to heat conduction; phi n-1 Represents the heat of the micro-element flowing in the negative direction of y due to heat conduction; phi l+1 Represents the heat of the micro element in the positive direction of z due to heat conduction; phi l-1 Representing the heat in the negative z direction of the element due to thermal conduction.
3. The method for measuring the thermophysical property of a thermal barrier coating according to claim 2, wherein:
wherein Δ x, Δ y and Δ z represent the lengths of the micro-elements in the x, y and z directions, respectively, λ represents the thermal conductivity of the micro-elements, and T represents the thermal conductivity of the micro-elements (m+1,n,l) And T (m-1,n,l) Respectively representing the temperatures, T, of two units in front and behind the infinitesimal in the x direction (m,n+1,l) And T (m,n-1,l) Respectively representing the temperature of the front unit and the rear unit of the infinitesimal in the y direction; t is a unit of (m,n,l+1) And T (m,n,l-1) Respectively representing the temperature of two units before and after the infinitesimal in the z direction;
p deltax deltay deltaz represents the amount of heat that the laser heats up flowing into the element,
where P is the laser incident intensity, τ L Is the laser absorption depth, r 0 Is the size of the laser spot, r is the distance from the center line of the laser spot, z is the distance from the outer surface of the coating, P 0 Out-of-spot P =0 for average power density;
Φ h ＝h(T (m,n,l) -T 0 ) Deltax and Deltay represent the convective heat transfer between the material surface infinitesimal elements and the surrounding environment, wherein h is the convective heat transfer coefficient of the sample surface, and T is (m,n,l) Temperature, T, of the infinitesimal 0 Is the ambient temperature; because the convective heat transfer process only occurs on the surface of the material and in the interior of the material h ＝0；
4. The method for measuring the thermophysical property of the thermal barrier coating according to claim 1, wherein the step S2 is performed by processing an infrared thermography taken by an infrared imager through a data collecting computer to obtain a temperature distribution map, and specifically includes obtaining the temperature distribution map through infrared thermography processing software preset in the data collecting computer.
5. The method for measuring the thermophysical property of a thermal barrier coating according to claim 1, wherein: before measurement, the surface emissivity of the thermal insulation coating is measured in an experiment, a thermocouple is used for measuring the surface temperature of the thermal insulation coating, the surface emissivity of the material of the infrared imager is adjusted, and when the surface temperature measured by the infrared imager is the same as the temperature measured by the thermocouple, the surface emissivity set by the infrared imager is the real emissivity of the thermal insulation coating.
6. A thermal property measuring apparatus for a thermal barrier coating, comprising: the device comprises a laser connected with a laser controller, an infrared camera facing a heat insulation coating, a data processing module connected with the infrared camera, a thermocouple probe in contact with the coating, a thermocouple temperature measuring instrument, a convex lens controlled by a single-axis displacement platform, a shell and a data collecting computer; the infrared imager comprises an optical lens and an infrared imager host, and is characterized in that a laser, a convex lens and a sample are kept on the same optical path and are arranged at the bottom of the shell, and the infrared imager comprises an optical lens and an infrared imager host which are arranged at the bottom of the shell.
7. The thermal property measurement device of a thermal barrier coating according to claim 6, wherein the thickness of the thermal barrier coating is 10 μm to 10 mm.
8. The method and apparatus for measuring the thermophysical properties of a thermal barrier coating according to claim 6, wherein the angle between the incident light path of the laser and the detection light path of the thermal infrared imager is less than or equal to 30 °.
9. The thermal property measurement device of a thermal barrier coating according to claim 5, wherein the uniaxial displacement stage controls the convex lens to move back and forth along the optical path to adjust the size of the laser spot.
10. The thermal property measurement device of a thermal barrier coating according to claim 9, wherein a thermal conductivity of 10 can be achieved -3 The material properties of W/(m × k) are effectively measured.
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| RU2731112C1 (en) * | 2019-05-28 | 2020-08-28 | Александр Валерьевич Бояринцев | Method of determining heat conductivity coefficient of heat-insulating coatings based on hollow microspheres using thermal imager |
| CN112630261A (en) * | 2020-12-11 | 2021-04-09 | 武汉大学 | Measuring device and measuring method for multiple thermophysical parameters of material |
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| RU2731112C1 (en) * | 2019-05-28 | 2020-08-28 | Александр Валерьевич Бояринцев | Method of determining heat conductivity coefficient of heat-insulating coatings based on hollow microspheres using thermal imager |
| CN112630261A (en) * | 2020-12-11 | 2021-04-09 | 武汉大学 | Measuring device and measuring method for multiple thermophysical parameters of material |
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