JP2003042857A - Ultrasonic temperature measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ultrasonic temperature measuring apparatus by which the temperature change of a fluid coming into contact with the inner surface of a structure can be measured nondestructively. SOLUTION: In the measuring apparatus, ultrasonic waves are transmitted to the outer surface of the structure containing the fluid, an ultrasonic echo signal which is reflected by the interface between the thick wall of the structure and the contained fluid is fetched, and the temperature change of the fluid at the interface between the structure and the contained fluid is continuously measured by using a fact that the amplitude of the ultrasonic echo signal is changed on the basis of the temperature characteristic of an acoustic impedance. The temperature change of the fluid coming into contact with the inner surface of the structure can be measured nondestructively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal distribution in a thermal stratification or the like of a fluid such as water or a molten metal contained in a structure such as a pipe or a container, a flow velocity distribution and a confluence portion of fluids having different temperatures. The present invention relates to an ultrasonic temperature measuring device for nondestructively measuring the temperature change of a fluid in contact with the inner surface of a pipe or a container from the outer surface of the pipe or the container in order to evaluate striping.

[0002]

2. Description of the Related Art Conventionally, as a method of nondestructively measuring the temperature and temperature distribution of a fluid such as water or molten metal contained in a structure such as a pipe or a container and its fluctuation, The measurement was performed by contacting the surface or using a thermocouple built in the well.

However, the measurement by such a thermocouple is
Since it is performed through a structure with a constant wall thickness, it is not possible to measure a fast response of less than tens of seconds because of poor response. It was also difficult to measure the average temperature and distribution of the fluid.

[0004]

On the other hand, in plants such as nuclear power plants and chemical plants that handle high-temperature fluids, there are periodic temperature changes in the confluence of the fluids of different temperatures and the jetting portion of the high-temperature fluid. In order to monitor and evaluate the fatigue of a structure, it is necessary to measure the degree of temperature change and fluctuation period of the fluid temperature at the interface of the fluid in contact with the structure. However, it is necessary to detect non-destructively the leak detection from the stop valve that separates fluids of different temperatures and the formation and fluctuation of thermal stratification generated in the fluid in the horizontal piping. In addition, it is also necessary to measure non-destructively the concentric temperature distribution that transiently occurs in the outlet pipe portion of the device that performs heat exchange.

The present invention has been made in view of the above circumstances, and its problems are different in temperature distribution and flow velocity distribution of thermal stratification of fluid such as water and molten metal contained in structures such as pipes and containers, and the like. An object of the present invention is to provide an ultrasonic temperature measuring device capable of nondestructively measuring a temperature change of a fluid in contact with an inner surface of a pipe or a container, which is necessary for evaluating thermal striping generated in a portion where a fluid having a temperature merges.

[0006]

In order to solve the above-mentioned problems, an ultrasonic temperature measuring device according to a first aspect of the present invention transmits ultrasonic waves to the outer surface of a structure containing a fluid, and the thick part of the structure. Taking in the ultrasonic echo signal reflected at the interface of the fluid to be contained, and utilizing the fact that the amplitude intensity of the ultrasonic echo signal changes based on the temperature characteristics of the acoustic impedance of the fluid, It is characterized by continuously measuring changes in fluid temperature at the interface.

According to a second aspect of the invention, in the ultrasonic temperature measuring device according to the first aspect, in order to measure the change in the amplitude intensity of the ultrasonic echo signal, the waveform near the peak of the captured ultrasonic echo signal is measured. It is characterized by amplifying and measuring the variation.

According to a third aspect of the invention, in the ultrasonic temperature measuring device according to the first aspect, the peak level is detected from the taken-in ultrasonic echo signal in order to measure the change in the amplitude intensity of the ultrasonic echo signal. It is characterized in that the attenuation characteristic of each peak level is obtained according to the number of reflections.

According to a fourth aspect of the invention, in the ultrasonic temperature measuring device according to the first aspect, in order to detect the impedance change due to the temperature change of the fluid in contact with the inner surface of the pipe, the resonance frequency near the resonance frequency depending on the plate thickness of the pipe is detected. It is characterized in that the attenuation of the vibration is detected by utilizing the vibration. According to the first to fourth aspects, the temperature change of the internal fluid in contact with the inner surface of the structure can be continuously measured.

According to a fifth aspect of the present invention, in the ultrasonic temperature measuring device according to the first aspect, the inner surface of the structure, which penetrates the interface between the thick portion of the structure and the fluid contained therein and faces the structure through the fluid. It is characterized by receiving the ultrasonic echo reflected by the ultrasonic echo, determining the ultrasonic propagation velocity in the fluid from the ultrasonic propagation time in the fluid containing the received echo, and measuring the average temperature of the fluid and the fluid temperature near the interface. To do.

According to a sixth aspect of the present invention, in the ultrasonic temperature measuring device according to the first aspect, the transmitting and receiving ultrasonic transducers are fixed at positions separated from each other on the outer surface of the structure, and the ultrasonic wave is transmitted. Measuring the fluid temperature change at the interface between the structure and the contained fluid by receiving the ultrasonic echo reflected by the wall thickness part of the structure from the ultrasonic transducer of Is characterized by.

According to a seventh aspect of the present invention, ultrasonic waves are transmitted to the outer surface of the structure containing the fluid, and ultrasonic echo signals reflected at the thermal stratification interface formed in the fluid inside the structure are taken in, It is characterized by measuring the presence or absence of thermal stratification and the fluctuation of thermal stratification. According to claims 5 to 7,
The formation and position of the thermal stratification interface and its variation can be measured.

According to an eighth aspect of the present invention, an ultrasonic echo signal is generated by transmitting ultrasonic waves to the outer surface of a structure containing a fluid, passing through the fluid, and receiving again through the thick portion of the structure at the same time. Therefore, the average temperature in different paths in the fluid is measured.

According to a ninth aspect of the invention, in the ultrasonic temperature measuring device according to the eighth aspect, at least the angle of incidence of the ultrasonic wave on the structure is increased, or a voltage element that laterally vibrates is used to obtain the fluid. It is characterized by measuring the average temperature of the fluid in a portion relatively close to the inner surface of the structure.

According to a tenth aspect of the present invention, in the ultrasonic temperature measuring device according to the eighth aspect, ultrasonic wave transmission / reception is performed bidirectionally, the ultrasonic wave propagation time in the fluid is measured in both directions, and the delay of both is performed. It is characterized in that a time difference and a sum are created, the average temperature is detected from the sum of the delay times, and the moving speed of the medium in the space is detected from the difference of the delay times.

According to the eighth to tenth aspects, since the ultrasonic waves can be transmitted to a wide area from the center of the structure to the vicinity of the inner surface of the structure, the accuracy of measuring the concentric temperature distribution is improved. be able to.

According to an eleventh aspect of the present invention, in the ultrasonic temperature measuring apparatus according to the eighth aspect, the frequency of the voltage signal of the ultrasonic wave for transmission is changed to specify the ultrasonic wave that penetrates the thick portion of the structure. It is characterized in that the path length according to the directivity angle of is adjusted to an integral multiple of a half wavelength. According to the eleventh aspect, it is possible to transmit the ultrasonic beam having a high intensity over a wider range into the fluid.

By the way, as a method of measuring the degree of temperature change and the fluctuation period of the fluid temperature at the interface of the fluid in contact with the structure, there is a method of utilizing the temperature change of the acoustic impedance of the fluid.

Also in the measurement of thermal stratification, there is a method of observing the position and fluctuation of thermal stratification with good response by measuring ultrasonic reflection echoes due to the difference in acoustic impedance at the thermal stratification interface.

Further, in order to measure the temperature distribution of the fluid in the pipe or the container, the average temperature data in as many different paths as possible are required, but the average temperature can be obtained if the relationship between the sonic velocity of the fluid and the temperature is known. It can be obtained from the propagation time of the ultrasonic wave that has penetrated through the fluid in the pipe or container.
However, especially in a circular pipe or container and a fluid interface, the sound is narrowed in the fluid due to the influence of refraction, and it is difficult to transmit ultrasonic waves in the vicinity of the pipe or container. Use low shear wave ultrasound. In addition, by adjusting the frequency of the transmitted ultrasonic wave to a value that has the best transmission efficiency, it is possible to have a wide directivity angle in the fluid and realize good ultrasonic transmission characteristics.

By the way, as a method of measuring the degree of temperature change and the fluctuation period of the fluid temperature at the interface of the fluid in contact with the structure, the temperature change of the acoustic impedance of the fluid can be used. For example, when high-temperature water is flowing through the steel pipe, the sonic velocity decreases as the temperature rises, so the impedance of the fluid decreases. The change of the impedance Z ₂ of the steel material is smaller than the change of the impedance Z ₁ of the fluid, and the sound pressure reflectance P _R of the reflected ultrasonic echo on the inner surface of the pipe shown by the following equation is expressed by the following equation. Varies with fluid temperature. _{P R = (Z 2 -Z 1} ) / (Z 2 + Z 1)

However, since the change is small, by measuring multiple echoes at the interface between the thick portion of the pipe and the fluid,
The sound pressure reflectance P _R can be multiplied by the number of reflections to emphasize the change. The table below shows the changes of the multiple echo level once, three times, six times and ten times. In the table, it is expected that the echo level change of about 3 to 5% will be measured with the temperature change of 40 ° C. in the case of 6 times of multiple echo, and it can be sufficiently measured. Further, by numerically expressing the attenuation characteristic of the reflection echo level with respect to the number of reflections at each temperature with a regression curve, stable and highly accurate measurement is possible.

[0023]

[Table 1]

Further, also in the measurement of thermal stratification, if the interface is clear and stable, the reflection at the interface occurs similarly by utilizing the temperature change of the acoustic impedance of the fluid.
For example, the acoustic impedance of water at 200 ° C. is about 1.
Since this becomes about 1.2 at 3,240 ° C., the sound pressure reflectance P _R of the reflected ultrasonic echo is 4% as shown below, and the position of thermal stratification generated in the fluid in the horizontal pipe section It is possible to observe fluctuations with good response. _{P R = (Z 2 -Z 1} ) / (Z 2 + Z 1) = (1.3-1.2) / (1.3 + 1.2) = 0.04

Further, in order to measure the temperature distribution generated in the fluid in the pipe or the container, average temperature data in as many different paths as possible are required. If there are average temperature data in many paths, the temperature distribution can be obtained by solving the conventional CT method (back projection) or simultaneous equations. If you have little data,
For example, in the case of thermal stratification, the temperature distribution shape can be stratified in the horizontal direction, or can be evaluated after concentric circles based on the analysis result.

However, a problem here is the influence of refraction at the fluid interface in a pipe or container having a circular cross section. The sound velocity of piping material is 5900 m / s for carbon iron.
ec. It is about 1000m-1500m / in hot water
sec. Since it is quite small, ultrasonic waves transmitted at a wide directional angle narrow when entering a fluid from a pipe or a container and are refracted toward the center of the pipe or the container.

Therefore, it is difficult to transmit ultrasonic waves to a region near the pipe or container, and the temperature of that portion cannot be measured. Therefore, by using a transverse ultrasonic wave having a low propagation speed in a solid such as steel, the refractive index when passing through a fluid can be lowered.

Further, since the transmittance of ultrasonic waves in the thickness of the plate material becomes maximum at an integral multiple of 1/2 of the wavelength, the transmission angle of the ultrasonic waves propagating through the thick portion of the pipe or container in the plate material is Accordingly, by adjusting the frequency so that the transmission path length is an integral multiple of ½ of the wavelength, it is possible to have a wide directional characteristic and realize a good ultrasonic transmission characteristic.

Furthermore, when there is a flow in the fluid whose temperature distribution is to be measured, the sound wave passing through the fluid is
The propagation velocity changes under the influence of the flow. Therefore, in order to estimate the sound velocity from the propagation time of the signal and to evaluate the average temperature inside the fluid, the influence of the flow must be removed.

Therefore, the following measurement is performed. The ultrasonic wave transmitted from the ultrasonic transducer A is received by the opposed ultrasonic transducer B, and the delay time of arrival of the signal is detected. Next, a signal is transmitted from the ultrasonic transducer B and received by the ultrasonic transducer A within a time period in which the state of the region through which the sound wave passes does not change, and the delay arrival time of the signal is detected. Let C be the average speed of sound determined by the temperature inside the fluid. The velocity of the fluid is U, the distance between the ultrasonic transducers A and B is L, the arrival delay time of the signal transmitted from the ultrasonic transducer A and received by the ultrasonic transducer B is T1, and conversely with the ultrasonic transducer B. The delay time of the signal transmitted and received by the ultrasonic transducer A is T2. At that time, the propagation time of the signal is T1 = L / (C +
U) and T2 = L / (C−U). As a result, if the sum of the delay time of the signals obtained by the transmission and reception of each other and the speed obtained from the distance between the ultrasonic transducers and the difference are made, C =
(L / T1 + L / T2) / 2 and U = (L / T1-L / T
2) / 2, the average sound velocity C of the fluid, and the average flow velocity U can be detected. The average temperature of the fluid can be calculated from the average sound velocity.

Then, the vibration is excited by vibrating from the outer surface of the pipe at a frequency component that resonates with the thickness of the pipe (of course, a higher resonance frequency may be used) and a frequency near it. The excited vibration is received, the transfer function of the transmission signal and the reception signal is created, and the frequency is analyzed. From the results of frequency analysis, the half-value width of the resonance frequency is determined, and the damping coefficient of the vibration is determined. This damping coefficient consists of a component that propagates in the fluid inside the pipe and a component that propagates along the pipe surface. The fluid temperature in contact with the inner surface of the pipe can be measured by detecting the change due to the change based on the change in the half-value width of the resonance frequency. In order to improve the detection accuracy, it is desirable to uniformly vibrate the surface of the pipe in as wide a range as possible. Therefore, an ultrasonic transducer that vibrates the surface of the pipe preferably has a large vibration area.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of a first embodiment (corresponding to claims 1 to 4) of the present invention. As shown in the figure, the present embodiment is an ultrasonic temperature measuring device for measuring the temperature change of a fluid in contact with the inner surface of a container. That is, the ultrasonic transducer 3 is attached to the surface of the pipe 2 containing the internal fluid 1 whose temperature is changing with time by the acoustic coupling agent 4.
It is pressed and fixed through. An electric signal of a pulse wave, a burst wave, or a continuous wave is transmitted from the transmitter 5 housed in the measuring device 21 via the switch 12.
The multiple ultrasonic echo U transmitted from the ultrasonic transducer 3 is generated by the multiple reflection between the interface of the internal fluid 1 and the pipe 2 and the surface of the pipe 2 while being attenuated.

This multiple ultrasonic signal is converted into an electric signal by the ultrasonic transducer 3 and is amplified by the amplifier 7 in the receiver 6.
, The negative bias component of the setter 9 is added by the adder 8, and only the positive component is transmitted via the amplifier 7 on the output side to select a waveform near the peak of the multiple ultrasonic echo U. Can be amplified. The expanded waveform near the peak of the amplified multiple ultrasonic echo U is then A
The signal is converted into a digital signal by the / D converter 10, and the computer 11
Is taken into. The computer 11 calculates the peak level of the multiple ultrasonic echoes U from the captured waveform and repeats it at a constant cycle to continuously measure the temperature change of the internal fluid 1 in contact with the inner surface of the pipe 2. You can

FIG. 2 is a temperature characteristic diagram of the amplitude of the multiple ultrasonic echo U. That is, it is a graph showing the change in intensity of the multiple ultrasonic echoes U due to the change in acoustic impedance due to the change in temperature of the internal fluid 1, the number of multiple reflections being a parameter. The horizontal axis of this graph is fluid temperature (℃),
The vertical axis represents the reflection echo level with reference to the first reflection echo when the internal fluid 1 is 280 ° C. Curve 31
Shows the case of one reflection, the curve 32 shows the case of three reflections, the curve 33 shows the case of six reflections, and the curve 34 shows the case of ten reflections.

In the graph of FIG. 2, the impedance Z ₁ of the internal fluid ₁ is calculated based on the data of the ultrasonic technical handbook, and the impedance Z _{2 of the} pipe ₂ is constant,
The intensity of the multiple ultrasonic echoes U is determined by the sound pressure reflectance P _R of the reflected ultrasonic echoes at the interface between the pipe 2 and the internal fluid 1 being P _R = (Z ₂ −Z ₁ ) / (Z ₂ + Z ₁ ). It is estimated as if there is. As shown in FIG.
As the number of multiple reflections increases, the temperature of the internal fluid 1 in contact with the inner surface of the pipe 2 and its temporal change can be measured with high accuracy and high speed response.

Further, a continuous wave electric signal having a frequency component resonating with the plate thickness of the pipe 2 (although a higher resonance frequency may be used, of course) and a frequency close thereto is applied from the transmitter 5 to the ultrasonic transducer 3. Then, the outer surface of the pipe 2 is vibrated to excite the vibration. After the excited vibration is received by the ultrasonic transducer 3 and taken into the computer 11,
A transfer function of the transmission signal and the reception signal is created and frequency analysis is performed.
From the results of frequency analysis, the half-value width of the resonance frequency is determined, and the damping coefficient of the vibration is determined. From the continuous measurement result of the damping coefficient, it is possible to continuously measure the temperature change of the fluid in contact with the inner surface of the pipe.

FIG. 3 is a configuration diagram of a second embodiment (corresponding to claims 5 to 7) of the present invention, and is a diagram for explaining a method for measuring a thermal stratification interface generated in an internal fluid. As shown in FIG. 7A, in this embodiment, the ultrasonic waves transmitted from the transmission oblique-angle ultrasonic transducer 45, which is pressed and fixed to the surface of the pipe 41, propagates through the pipe 41 into the internal fluid 42. Then, a part is reflected at the thermal stratification interface 43 and received by the reception oblique-angle ultrasonic transducer 46. In addition, the ultrasonic waves transmitted through the thermal stratification interface 43 are further propagated and reflected by the inner surface of the opposed pipe 41, and are received by the oblique-angle ultrasonic transducer for reception, and the above received signals are measured by the measuring device 21 shown in FIG. By receiving and measuring the peak level and the peak time of the reflected ultrasonic echo U1 at a constant reflection cycle, the formation and position of the thermal stratification interface 43 and its fluctuation can be measured.

FIG. 6B shows an example of measuring the temperature fluctuation of the internal fluid 42 of the pipe 41 at the thermal stratification interface 43 by applying the ultrasonic temperature measuring device of the first embodiment. In particular, when the position of the thermal stratification interface 43 is unknown, the ultrasonic wave is transmitted from the transmission oblique-angle ultrasonic transducer 45 to the piping 4
1 can be measured obliquely with respect to the surface of No. 1 by receiving multiple ultrasonic echoes U2 that have been multiple-reflected several times and propagated in the radial direction of the pipe 41 by the reception-use oblique-angle ultrasonic transducer 46. it can.

FIG. 4 is a configuration diagram of a third embodiment (corresponding to claims 8 to 10) of the present invention. As shown in the figure, in the present embodiment, the fluid (region 1) 62, the fluid (region 2) 63, the fluid (region 3) 64,
An example is shown in which different concentric temperature regions formed of the fluid (region 4) 65 are formed. The ultrasonic wave transmitted from the transmitting ultrasonic transducer 66, which is pressed and fixed to the outer surface of the pipe 61, has a directivity angle determined by the wavelength λ of the ultrasonic wave in the pipe 61 and the piezoelectric element diameter d of the transmitting ultrasonic transducer 66. It propagates as a longitudinal ultrasonic beam having a spread of θ (θ ≈ Sin (λ / d)) and is refracted at the interface with the fluid 62, so that the spread of the beam becomes narrower and it is pressed against the opposing position of the pipe 61. Obtaining the average sound velocity by subtracting the propagation time of the pipe 61 from the propagation time of the ultrasonic waves received by the fixed reception trust ultrasonic transducer 67 or the reception trust ultrasonic transducer 69 and measured according to each propagation path. You can Furthermore, the average temperature can be obtained from the temperature characteristics of the average sound velocity and the sound velocity of the internal fluid. However, in the above method, the sound velocity of longitudinal ultrasonic waves is 5900 m /
sec. And the speed of sound of high-temperature water is 1000-1500 m
/ Sec. Since it is about the degree, the refraction angle is large and the ultrasonic wave does not spread sufficiently.

For this reason, a transmission oblique angle ultrasonic transducer 71, which transmits a transverse wave having a sound velocity close to half of a longitudinal wave, such as a piezoelectric element such as a Y-cut crystal, is pressed against and fixed to the surface of the pipe 61. Can be made smaller, and ultrasonic waves can be transmitted into the fluids 62 to 65 in the pipe 61 at a shallower angle with respect to the inner surface of the pipe 61.

By combining the above methods, ultrasonic waves can be transmitted in a wide area from the center of the pipe 61 to the vicinity of the inner surface of the pipe 61, and the accuracy of measuring the temperature distribution on the concentric circles shown in FIG. 4 can be improved. Can be improved. In actual measurement, the average ultrasonic velocity value obtained by continuously transmitting and receiving ultrasonic waves in the forward direction and the reverse direction in the transmitting ultrasonic transducer 66 and the receiving ultrasonic transducer 67 or the receiving ultrasonic transducer 69. Fluid 62, fluid 63, fluid 6
4. The influence of the flow in the fluid 65 can be canceled and the measurement accuracy of the average temperature can be improved. Further, the fluid 62, the fluid 63, and the fluid 6 are calculated from the difference values of the average temperature values.
4. The average flow velocity in each propagation path in the fluid 65 can be calculated. Further, by further increasing the number of measurement points, it becomes possible to measure an arbitrary temperature distribution.

FIG. 5 shows a fourth embodiment of the present invention (claim 11).
It is a block diagram of (correspondence). As shown in the figure, in the present embodiment, in order to efficiently transmit the ultrasonic wave from the pipe 61 into the fluid 62, the ultrasonic wave is transmitted from the piezoelectric element 80 in the transmitting ultrasonic transducer 66 that is pressed and fixed to the surface of the pipe 61. The measuring device 21 is arranged so that the propagation path length L1 of the vertically incident ultrasonic wave component U3 and the propagation path length L2 of the obliquely incident ultrasonic wave component U4 of the ultrasonic beam are integer multiples of 1/2 of the ultrasonic wave wavelength.
The burst signal whose transmission frequency is controlled by is applied via the lead wire 81.

In the present embodiment, when ultrasonic waves are transmitted through a plate-shaped material having a constant thickness, the transmission efficiency is improved when the plate thickness becomes an integral multiple of 1/2 of the wavelength of the ultrasonic waves. , An ultrasonic beam of high intensity over a wider range can be transmitted into the fluid 62.

[0044]

As described above, according to the present invention,
Temperature change of the fluid in contact with the inner surface of the pipe or container, which is necessary to evaluate the temperature distribution and flow velocity distribution of the thermal stratification of the fluid contained in the structure, and the thermal striping that occurs at the part where the fluids of different temperatures join. It is possible to provide an ultrasonic temperature measuring device capable of nondestructively measuring.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a first embodiment of the present invention.

FIG. 2 is a temperature characteristic diagram of amplitude of multiple echo signals.

FIG. 3 is a configuration diagram of a second embodiment of the present invention.

FIG. 4 is a configuration diagram of a third embodiment of the present invention.

FIG. 5 is a configuration diagram of a fourth embodiment of the present invention.

[Explanation of symbols]

1 ... Internal fluid, 2 ... Piping, 3 ... Ultrasonic transducer, 4 ... Acoustic coupling agent, 5 ... Transmitter, 6 ... Receiver,
7 ... Amplifier, 8 ... Adder, 9 ... Setting device, 10 ... A / D converter, 11 ... Calculator, 12 ... Switching device, 21 ... Measuring device,
U ... Multiple ultrasonic echoes, 31, 32, 33, 34 ... 1
Temperature characteristics of the reflection echo level of 1, 3, 6 and 10 times, 41 ... Piping, 42 ... Internal fluid, 43 ... Thermal stratification interface,
45 ... Transmission angled ultrasonic transducer, 46 ... Reception angled ultrasonic transducer, 49 ... Temperature fluctuation region, 61 ... Piping, 62 ... Fluid (region 1), 63 ... Fluid (region 2), 64 ... Fluid ( Area 3), 65 ... Fluid (area 4), 66 ... Transmission ultrasonic transducer, 67, 6
8, 69 ... Ultrasonic transducer for reception, 71 ... Oblique ultrasonic transducer for transmission, 72, 73 ... Ultrasonic transducer for reception, U1 ... Ultrasonic echo, U2 ... Multiple ultrasonic echo, 80 ... Piezoelectric element, 81 ... Lead wire, L
1, L2 ... Propagation path length, U3 ... Normal incident ultrasonic wave component, U
4 ... Obliquely incident ultrasonic wave component.

Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G01P 5/00 G01P 5/00 B (72) Inventor Kenji Ogura 8 Shinsita-cho, Isogo-ku, Yokohama-shi, Kanagawa Stock company Inside the Yokohama office (72) Inventor Michio Sato 8 Shinsita-cho, Isogo-ku, Yokohama-shi, Kanagawa Prefecture Toshiba Corporation Yokohama office (72) Inventor Takehiko Suzuki, Komukai-Toshiba, Saiwai-ku, Kawasaki-shi, Kanagawa Toshiba Research Consulting Co., Ltd. In-house F-term (reference) 2F056 EM00 VS01 VS03 VS04 VS09 2G047 AA01 BA03 BB01 BB02 BC01 BC02 BC19 CA01 EA10 EA11 GA03 GG24 GG28 GG32 GG42

Claims (11)

[Claims] 1. An ultrasonic wave is transmitted to the outer surface of a structure containing a fluid, and an ultrasonic echo signal reflected at the interface between the thick portion of the structure and the contained fluid is taken in to obtain the amplitude of the ultrasonic echo signal. An ultrasonic temperature measuring device characterized by continuously measuring a change in fluid temperature at an interface between the structure and the contained fluid by utilizing the fact that the intensity changes based on the temperature characteristic of the acoustic impedance of the fluid. 2. The ultrasonic temperature measuring device according to claim 1, wherein in order to measure a change in the amplitude intensity of the ultrasonic echo signal, a waveform in the vicinity of the peak of the taken ultrasonic echo signal is amplified and its fluctuation is measured. An ultrasonic temperature measuring device characterized by measuring. 3. The ultrasonic temperature measuring device according to claim 1, wherein a peak level is detected from the taken-in ultrasonic echo signal in order to measure a change in the amplitude intensity of the ultrasonic echo signal, and the peak level is detected. An ultrasonic temperature measuring device characterized by obtaining attenuation characteristics at each peak level. 4. The ultrasonic temperature measuring device according to claim 1, wherein, in order to detect an impedance change due to a temperature change of a fluid in contact with the inner surface of the pipe, vibration near the resonance frequency due to the plate thickness of the pipe is used. An ultrasonic temperature measuring device characterized by detecting the attenuation of 5. The ultrasonic temperature measuring device according to claim 1, which permeates an interface between a thick portion of a structure and an internal fluid,
The ultrasonic echoes reflected by the inner surfaces of the structure facing each other through the fluid are received, the ultrasonic propagation velocity in the fluid is calculated from the ultrasonic propagation time in the fluid contained in the received echo, and the average temperature of the fluid and the interface An ultrasonic temperature measuring device characterized by measuring a fluid temperature in the vicinity. 6. The ultrasonic temperature measuring device according to claim 1, wherein the transmitting and receiving ultrasonic transducers are fixed at positions separated from each other on the outer surface of the structure, and are inclined from the transmitting ultrasonic transducer. An ultrasonic wave characterized by measuring the fluid temperature change at the interface between the structure and the inclusion fluid by receiving an ultrasonic echo that is incident at an angle and reflected at the thick part of the structure by an ultrasonic transducer for reception. Temperature measuring device. 7. The presence / absence of formation of a thermal stratification by transmitting an ultrasonic wave to the outer surface of a structure containing a fluid and capturing an ultrasonic echo signal reflected at a thermal stratification interface formed in the fluid inside the structure. And an ultrasonic temperature measuring device characterized by measuring fluctuations in thermal stratification. 8. An ultrasonic echo signal transmitted from an ultrasonic wave to the outer surface of a structure containing a fluid, transmitted through the fluid, and simultaneously received again through the thick portion of the structure, the difference in the fluid. An ultrasonic temperature measuring device characterized by measuring an average temperature in a route. 9. The ultrasonic temperature measuring device according to claim 8, wherein at least the ultrasonic wave incident angle to the structure is increased or a voltage element that laterally vibrates is used.
An ultrasonic temperature measuring device characterized by measuring an average temperature of a fluid in a portion relatively close to the inner surface of a structure in the fluid. 10. The ultrasonic temperature measuring device according to claim 8, wherein ultrasonic wave transmission / reception is bidirectionally performed, bidirectional ultrasonic wave propagation time in a fluid is measured, and a difference and a sum of delay times of the both are measured. An ultrasonic temperature measuring device, which is characterized by detecting an average temperature from a sum of delay times and detecting a moving speed of a medium in a space from a difference of delay times. 11. The ultrasonic temperature measuring device according to claim 8, wherein the frequency of the voltage signal of the ultrasonic wave for transmission is changed so as to respond to a specific directivity angle of the ultrasonic wave passing through the thick portion of the structure. An ultrasonic temperature measuring device characterized in that the path length is adjusted to an integral multiple of a half wavelength.