阅读说明：本技术 一种用于测量高温下表面波声速的系统及方法 (System and method for measuring sound velocity of surface wave at high temperature ) 是由 吕一楠 张红军 寇媛媛 孟永乐 朱婷 孙璞杰 李佼佼 薛开封 于 2020-07-22 设计创作，主要内容包括：本发明公开了一种用于测量高温下表面波声速的系统及方法,包括试块、温控箱、超声波换能器、超声模块及示波器,试块上开设有线槽,试块的左侧位于温控箱内,超声波换能器位于试块右端的侧面上,且线槽位于温控箱内,超声模块与示波器及超声波换能器相连接,该系统及方法能够较为准确的测量高温下表面波的声速。(The invention discloses a system and a method for measuring sound velocity of surface waves at high temperature, which comprises a test block, a temperature control box, an ultrasonic transducer, an ultrasonic module and an oscilloscope, wherein the test block is provided with a wire groove, the left side of the test block is positioned in the temperature control box, the ultrasonic transducer is positioned on the side surface of the right end of the test block, the wire groove is positioned in the temperature control box, and the ultrasonic module is connected with the oscilloscope and the ultrasonic transducer.)

1. The utility model provides a system for be used for measuring surface wave sound velocity under high temperature, a serial communication port, including test block (2), temperature control box (1), ultrasonic transducer (3), ultrasonic module (4) and oscilloscope (5), wire casing (6) have been seted up on test block (2), the left side of test block (2) is located temperature control box (1), ultrasonic transducer (3) are located the side of test block (2) right-hand member, and wire casing (6) are located temperature control box (1), ultrasonic module (4) are connected with oscilloscope (5) and ultrasonic transducer (3).

2. System for measuring the speed of sound of surface waves at high temperatures according to claim 1, characterized in that the distance between the raceway (6) and the left end face of the test block (2) is 300 mm.

3. The system for measuring the sound velocity of surface waves at high temperatures according to claim 1, characterized in that the width of the wire slot (6) is 0.2mm, the depth of the wire slot (6) is 10mm, and the length of the wire slot (6) is 50 mm.

4. System for measuring the speed of sound of surface waves at high temperatures according to claim 1, characterized in that the wireways (6) are distributed circumferentially.

5. The system for measuring the sound velocity of a surface wave at a high temperature according to claim 1, wherein the test block (2) has a rectangular parallelepiped structure, and the length, length and height of the test block (2) are 100mm, 1000mm and 10mm, respectively.

6. System for measuring the speed of sound of surface waves at high temperatures according to claim 1, characterized in that a layer of coupling agent is provided between the ultrasonic transducer (3) and the test block (2).

7. A method for measuring the speed of sound of a surface wave at high temperatures, comprising the steps of:

the left side of the test block (2) is heated to a preset temperature through the temperature control box (1) and is kept at the preset temperature, meanwhile, the temperature on the right end face of the test block (2) is lower than 50 ℃, the ultrasonic module (4) generates an electric signal, and sends the electrical signal into an ultrasonic transducer (3), the ultrasonic transducer (3) converts the electrical signal into a surface wave, the surface wave generates echo when passing through the wire groove (6) and the left end surface of the test block (2), the echo is converted into an echo signal by an ultrasonic transducer (3), an ultrasonic module (4) receives the echo signal and displays the echo signal by an oscilloscope (5), meanwhile, the time difference between the echo signal corresponding to the wire groove (6) and the echo signal corresponding to the left end surface of the test block (2) is measured through an oscilloscope (5), and calculating the sound velocity of the surface wave at the preset temperature according to the time difference and the distance between the wire groove (6) and the left end face of the test block (2).

Technical Field

The invention relates to a system and a method for measuring sound velocity, in particular to a system and a method for measuring sound velocity of surface wave at high temperature.

Background

Ultrasonic detection is one of the main methods of conventional nondestructive detection, and has been widely applied to the industries of machinery, electric power, petrochemical industry and the like due to the advantages of high sensitivity, light equipment, convenient operation, high detection efficiency and the like. Ultrasonic detection can be divided into transverse waves, longitudinal waves, surface waves, plate waves and the like according to different wave modes, the propagation speeds of different wave modes in the same medium are different, and the sound velocity is an important parameter in ultrasonic detection and has great influence on the accuracy of defect positioning. The sound velocity can change along with the change of factors such as the characteristic of a medium, the temperature of the medium and the like, the influence of the temperature on the sound velocity is mostly based on theoretical analysis at present, experimental tests are few, and the measurement of the sound velocity at high temperature is rare in domestic and foreign documents.

Surface waves are a form of ultrasonic propagation in a medium, which propagates along the surface of the medium and are commonly used to detect surface and near-surface defects. At normal temperature, the sound velocity of the surface wave can be measured by a contact method, the sound velocity measurement at high temperature faces the tolerance problem of an ultrasonic transducer and a couplant, the sensitivity of an echo can be greatly reduced when the transducer is in a high-temperature environment, the couplant can volatilize or chemically react with oxygen, and the detection precision is poor. In view of this, a system and a method for measuring the sound velocity of the surface wave at high temperature need to be developed, so as to provide a reference and a basis for realizing the online detection of the surface wave at high temperature.

Disclosure of Invention

The present invention is directed to overcoming the above-mentioned shortcomings of the prior art, and provides a system and a method for measuring the sound velocity of a surface wave at a high temperature, which can more accurately measure the sound velocity of a surface wave at a high temperature.

In order to achieve the purpose, the system for measuring the sound velocity of the surface wave at the high temperature comprises a test block, a temperature control box, an ultrasonic transducer, an ultrasonic module and an oscilloscope, wherein a wire groove is formed in the test block, the left side of the test block is positioned in the temperature control box, the ultrasonic transducer is positioned on the side face of the right end of the test block, the wire groove is positioned in the temperature control box, and the ultrasonic module is connected with the oscilloscope and the ultrasonic transducer.

The distance between the wire casing and the left end face of the test block is 300 mm.

The width of wire casing is 0.2mm, and the degree of depth of wire casing is 10mm, and the length of wire casing is 50 mm.

The wire grooves are distributed along the circumferential direction.

The test block is of a cuboid structure, and the length, the length and the height of the test block are respectively 100mm, 1000mm and 10 mm.

And a coupling agent layer is arranged between the ultrasonic transducer and the test block.

The method for measuring the sound velocity of the surface wave at the high temperature comprises the following steps:

heating the left side of the test block to a preset temperature through a temperature control box, keeping the temperature at the preset temperature, enabling the temperature on the right end face of the test block to be lower than 50 ℃, generating an electric signal through an ultrasonic module, sending the electric signal to an ultrasonic transducer, converting the electric signal into a surface wave through the ultrasonic transducer, generating an echo through a wire groove and the left end face of the test block, converting the echo into an echo signal through the ultrasonic transducer, receiving the echo signal through the ultrasonic module, displaying the echo signal through an oscilloscope, measuring the time difference between the echo signal corresponding to the wire groove and the echo signal corresponding to the left end face of the test block through the oscilloscope, and calculating the sound velocity of the surface wave at the preset temperature according to the time difference and the distance between the wire groove and the left end face of the test block.

The invention has the following beneficial effects:

when the system and the method for measuring the sound velocity of the surface wave at the high temperature are specifically operated, the left side of the test block is heated to the preset temperature through the temperature control box and is kept at the preset temperature, the surface wave generates echoes when passing through the wire groove and the left end surface of the test block, the echoes are converted into echo signals through the ultrasonic transducer, the echo signals are received by the ultrasonic module, the time difference between the echo signals corresponding to the wire groove and the echo signals corresponding to the left end surface of the test block is measured through the oscilloscope, the sound velocity of the surface wave at the preset temperature is calculated according to the time difference and the distance between the wire groove and the left end surface of the test block, the measurement result is accurate, and the operability is high.

Drawings

FIG. 1 is a schematic structural view of the present invention;

FIG. 2 is a front view of a test block 2 according to the present invention;

fig. 3 is a plan view of the test block 2 of the present invention.

Wherein, 1 is a temperature control box, 2 is a test block, 3 is an ultrasonic transducer, 4 is an ultrasonic module, 5 is an oscilloscope, and 6 is a wire casing.

Detailed Description

The invention is described in further detail below with reference to the accompanying drawings:

referring to fig. 1 to 3, the system for measuring the surface acoustic wave velocity at high temperature according to the present invention includes a test block 2, a temperature control box 1, an ultrasonic transducer 3, an ultrasonic module 4, and an oscilloscope 5, wherein the test block 2 is provided with a wire casing 6, the left side of the test block 2 is located in the temperature control box 1, the ultrasonic transducer 3 is located on the side surface of the right end of the test block 2, the wire casing 6 is located in the temperature control box 1, and the ultrasonic module 4 is connected to the oscilloscope 5 and the ultrasonic transducer 3.

The distance between the wire groove 6 and the left end face of the test block 2 is 300 mm; the width of the wire slot 6 is 0.2mm, the depth of the wire slot 6 is 10mm, and the length of the wire slot 6 is 50 mm; the wire grooves 6 are distributed along the circumferential direction; the test block 2 is of a cuboid structure, and the length, the length and the height of the test block 2 are respectively 100mm, 1000mm and 10 mm; a coupling agent layer is arranged between the ultrasonic transducer 3 and the test block 2.

The method for measuring the sound velocity of the surface wave at the high temperature comprises the following steps:

the left side of the test block 2 is heated to a preset temperature through the temperature control box 1 and is kept at the preset temperature, meanwhile, the temperature on the right end face of the test block 2 is less than 50 ℃, the ultrasonic module 4 generates an electric signal, and transmits the electrical signal into the ultrasonic transducer 3, the ultrasonic transducer 3 converts the electrical signal into a surface wave, the surface wave generates echo when passing through the wire slot 6 and the left end surface of the test block 2, the echo is converted into echo signal by the ultrasonic transducer 3, the ultrasonic module 4 receives the echo signal and displays the echo signal by the oscilloscope 5, meanwhile, the oscilloscope 5 is used for measuring the time difference between the echo signal corresponding to the wire slot 6 and the echo signal corresponding to the left end surface of the test block 2, and calculating the sound velocity of the surface wave at the preset temperature according to the time difference and the distance between the wire slot 6 and the left end surface of the test block 2.

The propagation time of the echo of the wire slot 6 at a certain temperature is t₁The propagation time of the echo at the left end face of the test block 2 is t₂The time difference Δ t between the echo of the wire slot 6 and the echo of the left end face of the test block 2 is t₂-t₁The linear expansion coefficient of the test block 2 at the preset temperature is α, the linear expansion amount Δ l between the wire slot 6 and the left end face of the test block 2 is 300 ×α, and the total distance l of the surface wave propagating in the region from the wire slot 6 to the left end face is 2 × (300+ Δ l), so that the sound velocity c of the surface wave at the preset temperature is_t＝l/Δt。

It should be noted that, the couplant layer and the ultrasonic transducer 3 are not in the temperature control box 1, so as to avoid the problem of tolerance of the couplant, and simultaneously avoid the problem that the echo sensitivity of the ultrasonic transducer 3 is greatly reduced in a high-temperature environment.