WO2022180748A1

WO2022180748A1 - Leakage amount estimation method, leakage amount estimation device, and leakage amount estimation system

Info

Publication number: WO2022180748A1
Application number: PCT/JP2021/007173
Authority: WO
Inventors: 有為田村
Original assignee: Ｊｆｅアドバンテック株式会社
Priority date: 2021-02-25
Filing date: 2021-02-25
Publication date: 2022-09-01
Also published as: JPWO2022180748A1; JP7075549B1

Abstract

A plurality of calibration curves are prepared that indicate a relationship between a parameter obtained when a gas leaks from a leakage detection object 2, the parameter including the sound pressure of sound waves generated accompanying the leakage, and the leakage amount of the gas. The parameter is detected when gas leaks from the leakage detection object 2. Any one of the prepared calibration curves is selected on the basis of the detected parameter. The leakage amount is estimated from the selected calibration curve on the basis of the detected sound pressure of sound waves generated accompanying the leakage.

Description

Leakage estimation method, leakage estimation device and leakage estimation system

The present invention relates to a leakage amount estimation method, a leakage amount estimation device, and a leakage amount estimation system.

Conventionally, there is a well-known method for estimating the amount of leakage of fluid leaked from pipes, etc., based on the sound pressure of ultrasonic waves generated at the time of leakage (see

Patent Documents

1 and 2, for example).

Patent Literature 1 discloses a method in which an ultrasonic sensor detects ultrasonic waves generated when a gas leaks, and the amount of gas leakage is estimated based on the peak value obtained by a peak detector. .

Patent Document 2 discloses a method of removing noise from the frequency components of the sound pressure generated from the leaking portion and estimating the amount of leakage from the obtained frequency components.

Japanese Utility Model Publication No. 6-28687 JP 2014-149208 A

However, in the methods disclosed in any of the above patent documents, the amount of leakage is estimated on the assumption that the sound pressure generated when leaking is linearly proportional to the amount of leakage. Therefore, the leakage amount cannot be estimated in a region where the generated sound pressure and the leakage amount are not linearly proportional. Specifically, in a region where the sound pressure level is low, there is a large divergence between the leakage amount estimated from the sound pressure and the actual leakage amount.

An object of the present invention is to provide a leakage amount estimation method, a leakage amount estimation device, and a leakage amount estimation system that can appropriately estimate the amount of leakage regardless of the difference in sound pressure level.

As a means for solving the above-mentioned problems, the present invention provides a parameter including a sound pressure of a sound wave generated by the leakage obtained when gas leaks from a leakage detection target, and a leakage amount of the gas. preparing a plurality of calibration curves showing the relationship of, detecting the parameter when gas leaks from the leakage detection object, and based on the detected parameter, any one of the prepared calibration curves A method of estimating a leakage amount, selecting one of the detected parameters and estimating the leakage amount from the selected calibration curve based on the sound pressure of the sound wave generated by the leakage from the detected parameters.

According to this, it is possible to select an appropriate calibration curve according to the difference in parameters obtained when gas leaks from the leakage detection target, and to accurately estimate the leakage amount.

The calibration curve may include a calibration curve represented by a linear function and a calibration curve represented by a nonlinear function.

According to this, by introducing a nonlinear function, it is possible to estimate the amount of leakage with sound pressure in areas where the generated sound pressure and the amount of leakage are not linearly proportional.

The calibration curve of the nonlinear function can be expressed by the following equation.

The coefficient c is preferably 3.

According to this, it is possible to estimate the amount of leakage when the leaking fluid is flowing in an incompressible subsonic flow.

wherein the parameter is the pressure of the gas in the leakage detection object when the gas leaks from the leakage detection object, and a plurality of pressure intervals are set in which the gas pressure in the leakage detection object is different; A calibration curve to be applied to each of the set pressure sections may be determined from the plurality of calibration curves.

The gas pressure threshold P _th for switching the calibration curve to be applied may be calculated based on the following equation.

When the number of calibration curves is 2, the threshold for switching the calibration curve to be applied with M=1 can be calculated using the above formula.

The parameter is a sound pressure of a sound wave when gas leaks from the leakage detection object, a plurality of sound pressure intervals having different sound pressures are set, and the set sound pressure intervals are obtained from the plurality of calibration curves. It is preferable to determine the calibration curve to be applied every time.

For the threshold value of the sound pressure interval, the sound pressure generated at the preset pressure threshold value in the simulated leak detection object may be used.

It is preferable to use the determined multiple calibration curves as one approximation function.

It is preferable to correct the sound pressure of the sound wave based on the amount of attenuation expected from the measurement environment.

It is preferable to measure the sound pressure of the sound wave for a predetermined period of time and detect the maximum sound pressure or the maximum leakage amount by peak hold.

It is preferable to measure the sound pressure of the sound wave from multiple directions and detect the maximum sound pressure or maximum leak amount by peak hold.

As a means for solving the above-mentioned problems, the present invention provides a parameter including sound pressure of sound wave of gas generated by the leakage, which is obtained when gas leaks from a leakage detection target, and a leak of the gas. a storage unit for storing a plurality of calibration curves showing the relationship between the gas and the amount of gas, a detection unit for detecting the parameter when the gas leaks from the leakage detection object, and one of the plurality of calibration curves from the parameter A leakage amount measuring device comprising: a selection unit for selecting either one; offer.

As a means for solving the above-mentioned problems, the present invention provides a parameter including sound pressure of sound wave of gas generated by the leakage, which is obtained when gas leaks from a leakage detection target, and a leak of the gas. a storage unit for storing a plurality of calibration curves showing the relationship between the gas and the amount of gas, a detection unit for detecting the parameter when the gas leaks from the leakage detection object, and one of the plurality of calibration curves from the parameter A leakage measurement system comprising: a selection unit that selects either one; offer.

According to the present invention, the leakage amount can be appropriately estimated regardless of the difference in the sound pressure level of the sound waves emitted from the fluid leaking from the leakage detection target.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic explanatory drawing which shows the usage form of the leak amount estimation apparatus which concerns on 1st Embodiment. FIG. 2 is a block diagram of the leakage amount estimation device of FIG. 1; The graph which shows the relationship between sound pressure and the amount of leakage. FIG. 3 is a flow chart showing a method of estimating the amount of leakage executed by the controller in FIG. 2; FIG. The block diagram of the leakage amount estimation apparatus which concerns on 2nd Embodiment. 6 is a flow chart showing a method of estimating the amount of leakage executed by the controller in FIG. 5; The schematic block diagram of the leak amount measuring system which concerns on other embodiment.

An embodiment of the present invention will be described below with reference to the accompanying drawings. It should be noted that the following description is essentially merely an example, and is not intended to limit the present invention, its applications, or its uses. Moreover, the drawings are schematic, and the ratio of each dimension is different from the actual one.

(First embodiment)
FIG. 1 shows an example in which the leakage amount estimation device 1 according to the first embodiment is adopted for estimating the leakage amount Q of fluid (gas) from a pipe 2, which is an example of a leakage detection target ( , the state of gas leakage from the pipe 2 is indicated by a two-dot chain line.).

The leakage amount estimation device 1 includes a detection unit 3, a storage unit 4, and a control unit 5, as shown in FIG.

The detection unit 3 includes a sound pressure detection unit 6. For example, as shown in FIG. It can be configured with a sound wave microphone 8 . By using the parabolic reflector 7, it is possible to improve the directivity and pinpoint the leakage point. The sound pressure level of the ultrasonic waves detected by the ultrasonic microphone 8 is calculated by a control unit, which will be described later.

The storage unit 4 is a storage device such as a hard disk or SSD (Solid State Drive). The storage unit 4 stores in advance a plurality of calibration curves indicating the relationship between the sound pressure S of the sound wave generated when the gas leaks from the leakage detection object and the leakage amount Q, and the leakage amount Q is estimated based on these calibration curves. A control program or the like for doing so is stored.

The calibration curve stored in advance in the storage unit 4 corresponds to compressible sonic flow, compressible subsonic flow, and incompressible subsonic flow according to the difference in flow velocity of the gas leaking from the leak detection object. There are 3 types. A supersonic flow in which the flow velocity v exceeds the speed of sound does not occur unless it passes through a tube with a special shape such as a Laval nozzle, so it is excluded here. Also, since sonic flow cannot be an incompressible flow in which the density ρ of the fluid is constant, only the compressible sonic flow in which the density ρ changes according to the change in the pressure P is considered. In addition, in a subsonic flow where the speed of sound is smaller than the sonic speed (Mach number M = 1) in all parts of the flow, if the flow is a low-speed flow (Mach number M < 0.3) where the change in density ρ can be ignored, the compressible fluid can be treated as an incompressible flow. Therefore, subsonic flow is divided into incompressible flow and compressible flow. Whether the leaking gas flow is a compressible sonic flow (M = 1), a compressible subsonic flow (0.3 ≤ M < 1), or an incompressible subsonic flow (M < 0 .3) is determined by the difference in sound pressure of sound waves emitted from the leaking gas. Here, the sound pressure of sound waves emitted when gas leaks from a simulated leak detection object is measured in advance, and the velocity of the leaking gas is estimated. Two sound pressure intervals are set, and the calibration curve is selected depending on which sound pressure interval the detected sound pressure belongs to.

In the compressible sonic flow (M = 1), which is the first sound pressure section with the highest sound pressure, when the sound pressure is S, the gas leakage amount Q is a linear function as in the conventional case (Equation 1). presume.

In the incompressible subsonic flow (M<0.3), which is the second sound pressure section with the lowest sound pressure, when the sound pressure is S, the leakage amount Q of the fluid is a nonlinear function (Equation 2) estimated according to

(Equation 2) is determined as follows. That is, when the flow velocity v of the leaking gas is low (M<0.3), it is known that the acoustic dipole is dominant as a cause of sound generation (for example, turbulence engineering (aeroacoustics) foundation) (see http://aero.me.tut.ac.jp/Lectures/Turbulence/turb_sound.pdf)). It is also known that the sound pressure S generated by the acoustic dipole has the relationship S∝ρv ³ , where ρ is the density of the fluid (for example, the basics of fluid noise (https://www.jstage. jst.go.jp/article/tsj1973/24/12/24_12_753/_pdf/-char/ja)). The leak amount Q has a relationship of Q∝ρv. Therefore, the following relationship is established between the amount of leakage Q and the sound pressure S.

Based on this relationship, the above (Equation 2) is derived, and the leakage amount Q is estimated from the sound pressure S. Note that (Equation 2) is a case where the leaking fluid is flowing in an incompressible subsonic flow, so the coefficient c can be set to 3.

It is known that when the flow velocity v of the leaking gas satisfies M≧0.3, the acoustic quadrupole is predominant as a factor in generating sound, and the generated sound pressure S satisfies the relationship S∝ρv ⁴ . there is Therefore, in the compressible subsonic flow (0.3≦M<1), which is the third sound pressure section in which the sound pressure is intermediate, it cannot be said that the above relationship (Equation 2) holds as it is. However, in compressible subsonic flow, we focused on the fact that even if we estimate the leakage amount Q based on the relationship established in incompressible subsonic flow from actual measurement data, there is not much error. (Equation 2) is used in the same way as the sonic flow.

FIG. 3 is a graph showing the relationship between the sound pressure S of sound waves and the amount of fluid leakage Q at the leak location. In the graph, each point is actually measured data, and the solid line is a calibration curve showing the relationship calculated by (Equation 1) and (Equation 2). By adopting the linear function of (Equation 1) when the flow velocity v is sonic and the nonlinear function of (Equation 2) when the flow velocity is subsonic, a relationship close to the actual measurement data can be obtained.

The control unit 5 includes a microcomputer having a CPU, ROM, RAM, etc. and various circuits. The control unit 5 reads the data detected by the sound pressure detection unit 6, and based on the read data, executes the control program read from the storage unit 4 using the RAM as a work area to perform leakage amount estimation processing. The control unit includes a selection unit 9 that functions by executing calibration curve selection processing, and an estimation unit 10 that functions by executing leakage amount estimation processing. The control unit 5 may be configured by hardware such as ASIC (Application Specific Integrated Circuit) or FPGA (Field Programmable Gate Array).

Next, the leakage amount estimation process in the first embodiment will be described according to the flowchart of FIG.

In the leakage amount estimation process, first, the sound pressure data of the leaking fluid (gas) detected by the sound pressure detection unit 6 is read (step S1). In this case, it is preferable that the detection by the sound pressure detection unit 6 is performed for a predetermined time (for example, about 30 seconds), and the maximum value detected by the peak hold at that time is used as the detection data. This is because the detected value varies depending on the state of leakage of the gas even during one detection, so that the maximum value that is determined to be the largest amount of leakage Q is selected.

Then, a sound pressure section identifying process is executed to identify a sound pressure section based on the read sound pressure data (step S2). In the sound pressure section specifying process, it is determined which sound pressure section set in advance the read sound pressure corresponds to.

Subsequently, a calibration curve selection process for selecting a calibration curve to be used based on the specified sound pressure interval is executed (step S3: selection unit). The selected calibration curve is either the first calibration curve specified by (Equation 1) or the second calibration curve specified by (Equation 2).

After that, a leakage amount calculation process is executed to calculate the leakage amount Q according to the calibration curve selected in step S3 based on the sound pressure data detected by the sound pressure detection unit 6 (step S4: calculation unit). In the leakage amount calculation process, for example, if the first calibration curve is selected, the detected sound pressure S is substituted into (Equation 1) to calculate the leakage amount Q. Further, if the second calibration curve is selected, the detected sound pressure S is substituted into (Equation 2) to calculate the leakage amount Q.

As described above, according to the first embodiment, since the calibration curve used for calculating the leakage amount Q is changed depending on the difference in the sound pressure S, the leakage amount Q estimated as a result of a series of processing and the actual leakage amount Q It is possible to suppress the error from the leakage amount of In particular, since the leak amount Q can be accurately estimated at a minute leak stage where the sound pressure level is low, it is possible to repair the leak portion at an early stage.

(Second embodiment)
As shown in FIG. 5, the second embodiment is different from the first embodiment in that the detection section 3 includes a pressure detection section 11 in addition to the sound pressure detection section 6 . Further, in the second embodiment, the threshold value of the pressure of the gas in the pipe 2 is calculated as follows, and compared with the calculated threshold value of the pressure, the pressure of the gas in the leak detection target is determined to be any pressure. It is also different from the first embodiment in that the calibration curve is selected based on whether it belongs to the interval and the leakage amount Q is estimated. In addition, the same code|symbol is attached|subjected about the structure similar to 1st Embodiment, and the description is abbreviate|omitted.

The pressure detection unit 11 is arranged inside the pipe 2 . For example, a pressure sensor can be used for the pressure detection unit 11 .

When the absolute pressure of the gas inside the pipe 2 is P and the absolute pressure outside the pipe (atmospheric pressure) is P ₀ , the flow velocity v (M: Mach number) at the leaking part is given by using the specific heat ratio γ of the leaking gas: It is represented by the following formula.

Therefore, from (Equation 3), the absolute pressure P of the gas that switches the calibration curve specified by (Equation 1) and (Equation 2) is calculated. Then, based on the pressure value, a pressure interval is set to determine which calibration curve is to be used. Here, the pressure value when the flow velocity v of the gas at the leaking portion becomes Mach number M=1 is the critical value of the compressible sonic flow and the compressible subsonic flow. As a result, the pressure is divided into the first pressure section and the second pressure section, which are larger than the critical value, and it is possible to specify to which pressure section the pressure value detected by the pressure detection unit 7 belongs.

If the leaking gas is of a different type, the value of the specific heat ratio γ in (Equation 3) will change. And P obtained from (Formula 3) also changes. Therefore, the threshold pressure P _th when determining which calibration curve to adopt will also change.

Also, when the absolute pressure P ₀ outside the pipe is different, the absolute pressure P _th of the gas inside the pipe 2 obtained from (Formula 3) also changes. Therefore, the threshold pressure P _th for determining which calibration curve to adopt also changes.

In this way, the pressure section can be set in consideration of the difference in the ratio of specific heats based on the difference in the absolute pressure outside the pipe and the type of gas. For example, when the absolute pressure P ₀ outside the pipe is equal to the atmospheric pressure (101.325 kPa) and the leaking gas is air or nitrogen, the specific heat ratio γ=1.40 and the atmospheric pressure is P ₀ =101. Since it is 325 kPa, P=191.8 kPa can be obtained by substituting the Mach number M=1, which is the threshold value of the flow velocity v. Therefore, if the pressure P in the pipe ₂ is about 90.4 kPa higher than the atmospheric pressure P0, the flow satisfies the Mach number M=1. Therefore, the calibration curve specified by (Equation 1) should be selected to estimate the leakage amount Q. Further, it can be seen that the flow satisfies Mach number M<1 if the pressure P in the pipe 2 is less than about 90.4 kPa. Therefore, the calibration curve specified by (Equation 2) is selected, and the leak amount Q is estimated.

It is also possible to sequentially calculate and update the threshold value P _th for switching the calibration curve by actually measuring the absolute pressure outside the pipe, investigating the type of leaking gas, and specifying the specific heat ratio. A threshold value P _th =191.8 kPa calculated with a ratio of specific heat γ=1.40 and P ₀ =101.325 kPa is used for a situation in which a large amount of leakage is predicted.

The leakage amount estimation process in the second embodiment will be described according to the flowchart shown in FIG.

In the leakage amount estimation process, first, the pressure data of the gas inside the pipe detected by the pressure detection unit is read (step S11). Then, the pressure section is specified based on the read pressure data (step S12). As described above, the pressure interval is specified from the value obtained by (Equation 3) based on the flow velocity, considering the difference in the specific heat ratio depending on the type of gas. Subsequently, a calibration curve selection process is executed to select a calibration curve to be used based on the specified pressure category (step S13). The calibration curves to be selected are two types, the first calibration curve specified by (Equation 1) and the second calibration curve specified by (Equation 2), as in the first embodiment.

Further, the sound pressure of the sound wave of the gas leaking from the leakage point detected by the sound pressure detection unit 6 is read (step S14), and the leakage amount Q is calculated according to the calibration curve selected in step S13 based on the sound pressure data. A leakage amount calculation process is executed (step S15: calculation unit). This leakage amount calculation process is the same as that of the first embodiment.

Thus, according to the second embodiment, as described above, the pressure interval is the value obtained by (Equation 3) based on the flow velocity v, considering the difference in the specific heat ratio γ depending on the type of gas. can be set from Therefore, it is possible to more accurately estimate the gas leakage amount.

It should be noted that the present invention is not limited to the configurations described in the above embodiments, and various modifications are possible.

In the above embodiment, the leakage amount Q is estimated based on two calibration curves, but it may be estimated using one calibration curve. Specifically, according to the following equation, the two calibration curves specified by (Equation 1) and (Equation 2) can be approximated to one calibration curve, and the calibration curve is selected according to the difference in sound pressure level no longer needed.

In the above embodiment, the difference in the measurement environment was not considered, but it may be considered, for example, the following cases are conceivable.

In the above embodiment, the distance between the leak location and the measurement position (sound pressure detection unit 6) was not considered, but it is preferable to correct the estimated leak amount Q according to the difference in this distance. Specifically, the sound pressure level generated by the leak attenuates with increasing distance from the leak location. Therefore, the amount of leakage Q is estimated by correcting the sound pressure level in consideration of this amount of attenuation. For example, based on the standard ISO-9613, the sound pressure level can be corrected in consideration of attenuation due to geometric diffusion and attenuation due to atmospheric absorption.

According to the standard ISO-9613, the amount of attenuation due to atmospheric absorption changes depending on the difference in temperature, humidity, and air pressure between the leak location and the measurement location (sound pressure detection unit 6), and also the frequency of the ultrasonic waves used for measurement. Therefore, these parameters may also be taken into consideration when correcting the sound pressure level. Similarly, the amount of attenuation may take into account reflections from floors, walls, and the like.

In the above embodiment, the leak detection angle was not considered, but it is preferable to correct the estimated leak amount Q according to the difference in the detection angle. Specifically, even if the sound pressure level is the same, if the angle between the pointing direction of the detection unit 3 (ultrasonic microphone 8) and the ejection direction of the leak position is different, the detected sound pressure S can be estimated as The leakage amount Q of the gas is different from the actual leakage amount Q of the gas. Therefore, the error of the leakage amount Q can be reduced based on the angle formed by the jetting direction at the leak point and the orientation direction of the detection unit. The sound pressure S reached its maximum value when the angle formed by the pointing direction of the detection unit 3 with respect to the jetting direction of the leaking gas was 15° to 35° (optimally 20°). Therefore, it can be seen that the calibration curve should be created based on the sound pressure S detected at this angle. However, it is difficult to ascertain the jetting direction in the case of leakage due to cracks or corrosion in the pipe 2 . Therefore, it is preferable to change the angle at which the microphone is directed toward the leakage point and to read the sound pressure S at the angle at which the detected sound pressure S becomes maximum as the detection data. For example, the detection unit 3 may be moved on the same circle or spherical surface centering on the leak point to detect the sound pressure of the sound wave emitted by the leaking gas. Further, the detection unit 3 may be associated with a device that measures the distance to the leak point, and perform attenuation correction based on the measured distance to estimate the maximum leak amount.

In the above-described embodiment, the leakage amount estimation device 1 is configured to include all of the detection unit 3, the storage unit 4, and the control unit 5, but these may not necessarily be configured to be included in one device. may be configured with different devices that are For example, as shown in FIG. 7, the first device 13 equipped with the detection unit 3 and the communication unit 12 is sent to the site by a drone or the like, and the obtained data is grasped by the control unit 5 on the server 14 side to determine the amount of leakage. You may make it estimate. Alternatively, the storage unit 4 may be provided on the server 14 side, and the leakage amount may be estimated by the control unit 5 on the client side. Each device may be composed of each member such as the detection unit 3 alone or may be configured by appropriately combining the members, and its usage pattern can be freely set.

1 Leak amount estimation device 2 Pipe (leak detection object)
3 detection unit 4 storage unit 5 control unit 6 sound pressure detection unit 7 parabolic reflector 8 ultrasonic microphone 9 selection unit 10 estimation unit 11 pressure detection unit

Claims

Preparing a plurality of calibration curves showing the relationship between the parameters including the sound pressure of the sound wave of the gas generated in association with the leakage, which is obtained when the gas leaks from the leakage detection target, and the leakage amount of the gas,
detecting the parameter when gas leaks from the leakage detection object;
selecting any one of the prepared calibration curves based on the detected parameter;
A leakage amount estimation method for estimating the leakage amount from the selected calibration curve based on the sound pressure of gas sound waves generated by leakage among the detected parameters.
　The leakage amount estimation method according to claim 1, wherein the plurality of calibration curves include a calibration curve represented by a linear function and a calibration curve represented by a nonlinear function.
3. The leakage amount estimation method according to claim 2, wherein the calibration curve of said nonlinear function is represented by the following equation.
The leakage amount estimation method according to claim 3, wherein the coefficient c is 3.
the parameter is the pressure of the gas in the leak detection target when the gas leaks from the leak detection target;
setting a plurality of pressure intervals in which the gas pressure in the leakage detection target is different;
The leakage amount estimation method according to any one of claims 1 to 4, wherein a calibration curve to be applied to each of the set pressure sections is determined from the plurality of calibration curves.
6. The leakage amount estimation method according to claim 5, wherein the gas pressure threshold Pth for switching the calibration curve to be applied is calculated based on the following equation.
The leakage amount estimation method according to claim 6, wherein when the number of the calibration curves is 2, the threshold for switching the calibration curve to be applied is calculated with M=1 in the formula.
the parameter is the sound pressure of sound waves when gas leaks from the leakage detection target;
setting a plurality of sound pressure intervals with different sound pressures;
The leakage amount estimation method according to any one of claims 1 to 4, wherein a calibration curve to be applied to each of the set sound pressure intervals is determined from the plurality of calibration curves.
The leakage amount estimation method according to claim 8, wherein the threshold value of the sound pressure interval uses a sound pressure generated at a preset pressure threshold value in the simulated leak detection object.
The leakage amount estimation method according to any one of claims 1 to 9, wherein a plurality of determined calibration curves are used as one approximation function.
The leakage amount estimation method according to any one of claims 1 to 10, wherein the sound pressure of the sound wave is corrected based on the amount of attenuation expected from the measurement environment.
The leakage amount estimation method according to any one of claims 1 to 11, wherein the sound pressure of the sound wave is measured for a predetermined period of time, and the maximum sound pressure or the maximum leakage amount is detected by peak hold.
　The leakage amount estimation method according to any one of claims 1 to 12, wherein the sound pressure of the sound wave is measured from a plurality of directions, and the maximum sound pressure or the maximum leakage amount is detected by peak hold.
A memory for storing a plurality of calibration curves indicating the relationship between a parameter obtained when gas leaks from a leak detection object and including the sound pressure of sound waves of the gas generated along with the leak, and the leak amount of the gas. Department and
a detection unit that detects the parameter when gas leaks from the leakage detection target;
a selection unit that selects one of the plurality of calibration curves from the parameters;
an estimating unit for estimating the amount of leakage from the selected calibration curve based on the sound pressure of the gas sound wave generated by the detected leakage;
A leakage measurement device comprising:
A memory for storing a plurality of calibration curves indicating the relationship between a parameter obtained when gas leaks from a leak detection object and including the sound pressure of sound waves of the gas generated along with the leak, and the leak amount of the gas. Department and
a detection unit that detects the parameter when gas leaks from the leakage detection target;
a selection unit that selects one of the plurality of calibration curves from the parameters;
an estimating unit for estimating the amount of leakage from the selected calibration curve based on the detected sound pressure of the gas sound wave generated by the leakage;
Leakage measurement system.