Method for measuring surface temperature of high-temperature solid structure based on ultrasonic evanescent wave amplitude

Abstract

The invention discloses a method for measuring the surface temperature of a high-temperature solid structure based on ultrasonic evanescent wave amplitudes, which belongs to the field of nondestructive measurement and comprises the following steps: under different surface temperature conditions, exciting ultrasonic waves above the high-temperature solid structure, and measuring the ultrasonic evanescent wave amplitudes under different surface temperatures; determining the incidence relation between the ultrasonic evanescent wave amplitude and the temperature; and after the incidence relation between the amplitude of the ultrasonic evanescent wave and the temperature is determined, in subsequent ultrasonic detection, the temperature of the surface of the high-temperature solid structure is calculated by combining the measured amplitude of the ultrasonic evanescent wave with a predetermined incidence relation between the amplitude of the ultrasonic evanescent wave and the temperature. The method does not depend on radiation emitted by the surface of the measured material, can stably measure in a high-temperature or extremely-high-temperature environment, and is good in real-time performance.

Description

Technical Field

[0001] The present invention relates to the field of non-destructive measurement, and more specifically, to a method for measuring the surface temperature of a high-temperature solid structure based on the amplitude of an ultrasonic evanescent wave. Background Art

[0002] For some high-temperature structures, the measurement and characterization of surface temperature distribution and changes are very critical. The dynamic changes in temperature may affect the stability and safety performance of the equipment. For example, on the turbine blades of an aircraft engine, different temperature distributions may cause thermal stress, leading to fatigue or crack formation. Monitoring surface temperature changes helps to analyze temperature gradients, thereby optimizing the design and avoiding structural problems. The advantages of ultrasonic measurement of the surface temperature of high-temperature structures are its non-contact nature, high temperature resistance, real-time monitoring capabilities, and the ability to adapt to complex environments. This makes it an important measurement method in some extreme temperature environments, especially when traditional contact temperature measurement technology is limited, ultrasound can provide an efficient and reliable solution. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a method for measuring the surface temperature of a high-temperature solid structure based on the amplitude of ultrasonic evanescent waves. Using the method of the present invention and conducting non-destructive detection experiments, the results show that: compared with commonly used ultrasonic temperature measurement acoustic signals such as transverse waves, longitudinal waves or plate waves, ultrasonic evanescent waves have stronger adaptability in harsh detection environments, very stable amplitude information, more convenient signal acquisition, and no need for post-processing such as filtering. It does not rely on the radiation emitted by the surface of the material being tested, and can achieve stable measurement and acquisition of amplitude signals in high or extremely high temperature environments, with good real-time performance.

[0004] The object of the present invention is achieved through the following solutions: A method for measuring the surface temperature of a high-temperature solid structure based on the amplitude of an ultrasonic evanescent wave comprises the following steps: Under different surface temperature conditions, ultrasonic waves are excited above the high-temperature solid structure, and the amplitude of ultrasonic evanescent waves at different surface temperatures is measured; Determine the correlation between the amplitude of ultrasonic evanescent wave and temperature; After the correlation between the ultrasonic evanescent wave amplitude and the temperature is determined, in subsequent ultrasonic detection, the temperature of the high-temperature solid structure surface is calculated by combining the ultrasonic evanescent wave amplitude measurement value with the predetermined correlation formula between the ultrasonic evanescent wave amplitude and the temperature.

[0005] Furthermore, the correlation between the ultrasonic evanescent wave amplitude and the temperature is specifically expressed by a linear or polynomial expression.

[0006] Furthermore, the correlation between the ultrasonic evanescent wave amplitude and the temperature is determined, and the correlation between the ultrasonic evanescent wave amplitude and the temperature is determined specifically for different materials.

[0007] Furthermore, the solid structure includes a pure metal solid structure, a high temperature alloy solid structure, a metal matrix composite material solid structure and a non-metal composite material solid structure.

[0008] Furthermore, the solid structure comprises a 304 stainless steel material solid structure.

[0009] Furthermore, when the solid structure is a solid structure of 304 stainless steel material, the correlation between the amplitude of the ultrasonic evanescent wave and the temperature is: R=-33.16T+23848.90; Wherein, R represents the amplitude of ultrasonic evanescent wave. When the surface temperature of 304 stainless steel is subsequently measured, the surface temperature T of the high-temperature structure is calculated based on the measured ultrasonic evanescent wave amplitude R and a predetermined correlation relationship.

[0010] The beneficial effects of the present invention include: The method of the present invention is not limited to the type of solid materials, and is applicable to pure metals, high-temperature alloys, metal-based composite materials and other non-metallic composite materials. As long as the ultrasonic evanescent wave can be excited on the surface of the material and its amplitude information can be collected, the surface temperature measurement of the structure can be realized. Based on the scheme of the present invention and through the non-destructive detection experiment, the results show that the ultrasonic evanescent wave is more adaptable to harsh detection environments than the commonly used ultrasonic temperature measurement acoustic signals such as transverse waves, longitudinal waves or plate waves, and the amplitude information is very stable, and the signal collection is more convenient, without the need for post-processing such as filtering. It does not rely on the radiation emitted from the surface of the material being tested, and can achieve stable measurement and collection of amplitude signals in high or extremely high temperature environments, with good real-time performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0012] Figure 1 This is a schematic diagram of ultrasonic detection; Figure 2 A flowchart of the method steps of an embodiment of the present invention; Figure 3 Schematic diagram of the experiment; Figure 4This is the ultrasonic evanescent wave information diagram in 304 stainless steel material at different surface temperatures; Figure 4 (a) is the ultrasonic echo signal diagram at different temperatures, and (b) is a local enlarged diagram of the evanescent wave changing with temperature; Figure 5 4 is a graph showing the relationship between the amplitude of ultrasonic evanescent waves and the temperature in stainless steel material in an embodiment of the present invention. DETAILED DESCRIPTION

[0013] All features disclosed in all embodiments in this specification, or steps in all methods or processes implicitly disclosed, except for mutually exclusive features and / or steps, can be combined and / or expanded or replaced in any manner.

[0014] In view of the current situation in the background, the present invention aims at the measurement demand of the high-temperature structure surface when the mechanical equipment is running, and proposes a method for monitoring the surface temperature of the solid structure based on ultrasonic evanescent waves. The method can realize real-time measurement of the surface temperature of the high-temperature structure when the machine equipment is working normally or stopped.

[0015] In the overall concept of the present invention, a significant advantage of ultrasonic evanescent wave in measuring surface temperature is that compared with ultrasonic temperature measurement acoustic signals such as transverse waves, longitudinal waves, and plate waves, the amplitude of evanescent waves has stronger anti-interference ability, more stable signals, convenient collection, and no need for filtering and post-processing. Another significant advantage is that it is insensitive to material type. Non-contact temperature measurement methods such as infrared imaging technology rely on the radiation emitted from the surface of the object, and the radiation intensity is closely related to the emissivity of the material. Different materials have different emissivities, which will lead to errors in infrared measurement. Infrared temperature measurement may be greatly affected, especially on materials with low emissivity (such as metals, mirror coatings, etc.). In addition, it can work stably in high temperature or extremely high temperature environments, has good real-time performance, and is suitable for structural surface temperature monitoring under extreme temperature conditions such as metal smelting and petrochemicals.

[0016] Furthermore, unlike traditional contact temperature measurement methods such as thermocouples and non-contact temperature measurement methods such as infrared imaging, the method for measuring the surface temperature of high-temperature structures based on the amplitude of ultrasonic evanescent waves proposed in the present invention is not limited to the type of solid materials, and is applicable to pure metals, high-temperature alloys, metal-based composites and other non-metallic composite materials. As long as ultrasonic evanescent waves can be excited on the surface of the material and its amplitude information can be collected, the surface temperature of the structure can be measured. It does not rely on the radiation emitted by the surface of the material being measured, can be stably measured in high or extremely high temperature environments, and has good real-time performance.

[0017] More specifically, the method of measuring and characterizing the temperature of a high-temperature solid surface based on the amplitude of an ultrasonic evanescent wave of the present invention includes the following contents: Ultrasonic evanescent waves are a type of wave that propagates along the surface of an object. They are a special form of ultrasonic waves. Evanescent waves usually propagate on the surface of solid materials, and their wave energy is mainly concentrated on the surface or near-surface area of ​​the object. As the propagation distance increases, the evanescent wave energy decays rapidly. Changes in temperature also cause changes in the amplitude of ultrasonic evanescent waves, and they show a certain regularity. Through non-destructive detection experiments, we found that: compared with commonly used ultrasonic temperature measurement acoustic signals such as transverse waves, longitudinal waves or plate waves, ultrasonic evanescent waves have stronger adaptability in harsh detection environments, very stable amplitude information, and more convenient signal acquisition, without the need for post-processing such as filtering. Based on the discovery of this regularity, the present invention proposes a corresponding technical solution: like Figure 1 As shown, first, ultrasonic waves are excited above the solid structure under different surface temperature conditions, and the amplitudes of the evanescent waves at different surface temperatures are observed and recorded.

[0018] Next, the correlation between the ultrasonic evanescent wave amplitude and the temperature is determined: the correlation can generally be expressed by a linear or polynomial expression, etc. Different materials have different relationships between the ultrasonic evanescent wave amplitude and the temperature, so the correlation between the ultrasonic evanescent wave amplitude and the temperature needs to be determined specifically for specific materials.

[0019] After the correlation between the ultrasonic evanescent wave amplitude and temperature is determined, in subsequent ultrasonic detection, the temperature of the solid structure surface can be obtained by combining the ultrasonic evanescent wave amplitude and the correlation between the ultrasonic evanescent wave amplitude and temperature. Figure 2 shown.

[0020] In other embodiments of the present invention, Figure 3 As shown in the figure, through the electromagnetic ultrasonic detection experiment, ultrasonic waves are excited above the 304 stainless steel material, and the ultrasonic evanescent wave amplitudes of the 10mm thick 304 stainless steel material at different surface temperatures are collected (such as Figure 4 As shown in Table 1, a thermocouple was attached to the surface of the material to detect the temperature change, and finally the correlation between the amplitude of ultrasonic evanescent wave and temperature in 304 stainless steel material was obtained, as shown in Table 1 and Figure 5 shown.

[0021] Table 1 Ultrasonic evanescent wave-temperature correlation data table

[0022] The calibration relationship is as follows: R =-33.16 T +23848.90; in, R Represents the amplitude of the ultrasonic evanescent wave. When measuring the surface temperature of 304 stainless steel, the amplitude of the ultrasonic evanescent wave can be measured experimentally.R Combined with the above formula, the surface temperature of the structure is calculated T .

[0023] The units involved in the embodiments of the present invention may be implemented by software or hardware, and the units described may also be arranged in a processor. The names of these units do not, in some cases, limit the units themselves.

[0024] According to one aspect of an embodiment of the present invention, a computer program product or a computer program is provided, the computer program product or the computer program includes a computer instruction, and the computer instruction is stored in a computer-readable storage medium. A processor of a computer device reads the computer instruction from the computer-readable storage medium, and the processor executes the computer instruction, so that the computer device executes the method provided in the above various optional implementations.

[0025] As another aspect, an embodiment of the present invention further provides a computer-readable medium, which may be included in the electronic device described in the above embodiment; or may exist independently without being assembled into the electronic device. The above computer-readable medium carries one or more programs, and when the above one or more programs are executed by an electronic device, the electronic device implements the method described in the above embodiment.

Claims

1. A method for measuring the surface temperature of a high-temperature solid structure based on the amplitude of an ultrasonic evanescent wave, characterized in that: The following steps are involved: Under different surface temperature conditions, ultrasonic waves are excited above the high-temperature solid structure, and the amplitude of ultrasonic evanescent waves at different surface temperatures is measured; Determine the correlation between the amplitude of ultrasonic evanescent wave and temperature; After the correlation between the ultrasonic evanescent wave amplitude and the temperature is determined, in subsequent ultrasonic detection, the temperature of the high-temperature solid structure surface is calculated by combining the ultrasonic evanescent wave amplitude measurement value with the predetermined correlation formula between the ultrasonic evanescent wave amplitude and the temperature.

2. The method for measuring the surface temperature of a high-temperature solid structure based on ultrasonic evanescent wave amplitude according to claim 1, characterized in that: The correlation between the ultrasonic evanescent wave amplitude and temperature is specifically expressed by a linear or polynomial expression.

3. The method for measuring the surface temperature of a high-temperature solid structure based on ultrasonic evanescent wave amplitude according to claim 1, characterized in that: The correlation between the amplitude of the ultrasonic evanescent wave and the temperature is determined, and the correlation between the amplitude of the ultrasonic evanescent wave and the temperature is determined specifically for different materials.

4. The method for measuring the surface temperature of a high-temperature solid structure based on ultrasonic evanescent wave amplitude according to claim 1, characterized in that: The solid structure includes a pure metal solid structure, a high temperature alloy solid structure, a metal matrix composite material solid structure and a non-metal composite material solid structure.

5. The method for measuring the surface temperature of a high-temperature solid structure based on ultrasonic evanescent wave amplitude according to claim 1, characterized in that: The solid structure comprises a 304 stainless steel material solid structure.

6. The method for measuring the surface temperature of a high-temperature solid structure based on the amplitude of ultrasonic evanescent waves according to claim 5, characterized in that: When the solid structure is a 304 stainless steel solid structure, the correlation between the ultrasonic evanescent wave amplitude and temperature is: R=-33.16T+23848.90; Wherein, R represents the amplitude of ultrasonic evanescent wave. When the surface temperature of 304 stainless steel is subsequently measured, the surface temperature T of the high-temperature structure is calculated based on the measured ultrasonic evanescent wave amplitude R and a predetermined correlation relationship.

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