NL2036070B1 - Ultrasonic gas flow meter - Google Patents

Ultrasonic gas flow meter Download PDF

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Publication number
NL2036070B1
NL2036070B1 NL2036070A NL2036070A NL2036070B1 NL 2036070 B1 NL2036070 B1 NL 2036070B1 NL 2036070 A NL2036070 A NL 2036070A NL 2036070 A NL2036070 A NL 2036070A NL 2036070 B1 NL2036070 B1 NL 2036070B1
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NL
Netherlands
Prior art keywords
sound velocity
measurement channel
flow
channel transducer
velocity measurement
Prior art date
Application number
NL2036070A
Other languages
Dutch (nl)
Inventor
Han Huaicheng
Sun Chuanbao
Zhou Zhiyuan
Zheng Fu
Yu Hui
Chen Jiechao
Original Assignee
Liaoning Sc Tech Co Ltd
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Priority to NL2036070A priority Critical patent/NL2036070B1/en
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Publication of NL2036070B1 publication Critical patent/NL2036070B1/en

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Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01FMEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/66Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by measuring frequency, phase shift or propagation time of electromagnetic or other waves, e.g. using ultrasonic flowmeters
    • G01F1/667Arrangements of transducers for ultrasonic flowmeters; Circuits for operating ultrasonic flowmeters
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01FMEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/66Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by measuring frequency, phase shift or propagation time of electromagnetic or other waves, e.g. using ultrasonic flowmeters
    • G01F1/667Arrangements of transducers for ultrasonic flowmeters; Circuits for operating ultrasonic flowmeters
    • G01F1/668Compensating or correcting for variations in velocity of sound

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Measuring Volume Flow (AREA)

Abstract

The present invention discloses an ultrasonic gas flow meter, and relates to the technical field of fluid flow detection. A sound velocity measurement channel is added in a vertical direction inside the flow meter, and a distance between two transducers of the channel meets a preset condition, i.e., a unique standard reference sound velocity can be calculated. A measurement control unit compares absolute values of differences between a plurality of sound velocity values calculated in a flow velocity measurement channel and the standard reference sound velocity with a set threshold, and locates a unique pulse 10 position to calculate an instantaneous flow. The present invention eliminates the need for automatic amplification in signal processing, simplif1es circuit design and complicated programmed determination, and reduces cost input.

Description

ULTRASONIC GAS FLOW METER
TECHNICAL FIELD
[01] The present invention relates to the technical field of fluid flow detection, and 3 more particularly to an ultrasonic gas flow meter.
BACKGROUND ART
[02] The multi-channel ultrasonic gas flow meters based on the transit time method are applied to trade measures of natural gas flow transportation. Ultrasonic gas flow meters are becoming increasingly popular because of their high measurement accuracy, wide range ratio, low pressure loss, no moving parts, and low maintenance cost.
[03] Typical echo waveforms are prone to wrong determination of sampling pulse positions due to channeling and wave hopping, thus affecting metering. This phenomenon is likely to lead to an inaccurate calculation of the sound velocity, and the metering accuracy will be affected as well. In order to reduce the substantial impact of the above phenomenon, most manufacturers of ultrasonic gas flow meters add automatic amplification and program-controlled determination in echo signal processing, resulting in an increased cost input.
SUMMARY
[04] The present invention provides an ultrasonic gas flow meter, which enables a real-time check of a sound velocity of a gas, obtains a unique standard sound velocity and a pulse signal corresponding thereto by comparing a standard reference sound velocity with sound velocity values of a flow measurement channel, and calculates the flow using a transit time method, thereby ensuring the accuracy of flow metering.
[05] In order to achieve the above object, the present invention provides the following solution.
[06] An ultrasonic gas flow meter includes:
[07] a flow measurement pipe through which a to-be-measured gas passes;
[08] a first sound velocity measurement channel transducer vertically mounted on the flow measurement pipe and configured to transmit a first sonic signal; the first sonic signal including a plurality of first pulse signals;
[09] a second sound velocity measurement channel transducer vertically mounted on the flow measurement pipe corresponding to the first sound velocity measurement channel transducer and configured to recerve the first sonic signal and transmit a second sonic signal; the first sound velocity measurement channel transducer being further 3 configured to receive the second sonic signal; the second sonic signal including a plurality of second pulse signals corresponding to the first pulse signals;
[10] a distance between the first sound velocity measurement channel transducer and the second sound velocity measurement channel transducer meeting a preset condition, including: only one standard reference sound velocity existing within a theoretical sound velocity bandwidth range among the calculated sound velocity values of the plurality of first pulse signals and the plurality of second pulse signals; the distance between the first sound velocity measurement channel transducer and the second sound velocity measurement channel transducer being 1-2 cm;
[11] a first flow velocity measurement channel transducer mounted on the flow measurement pipe and configured to transmit a downstream sonic signal; the downstream sonic signal including a plurality of downstream pulse signals; and
[12] a second flow velocity measurement channel transducer mounted on the flow measurement pipe in central symmetry to the first flow velocity measurement channel transducer and configured to receive the downstream sonic signal and transmit an upstream sonic signal; the first flow velocity measurement channel transducer being further configured to receive the upstream sonic signal; the upstream sonic signal including a plurality of upstream pulse signals corresponding to the downstream pulse signals.
[13] According to a specific embodiment provided in the present invention, the present invention discloses the following technical effects.
[14] The present invention provides an ultrasonic gas flow meter which, compared with a conventional ultrasonic flow meter that uses a sound velocity comparison method to detect a sound velocity, enables a real-time check of a sound velocity of a gas, obtains a unique standard reference sound velocity by determination and screening with respect to a theoretical sound velocity bandwidth range, determines a pulse position by comparing absolute values of differences between sound velocities in a flow velocity measurement channel and the standard reference sound velocity with a set threshold, and calculates the flow according to the principle of the transit time method, thereby ensuring the accuracy of flow metering.
BRIEF DESCRIPTION OF THE DRAWINGS
[15] FIG. 1 is an echo waveform typical in the prior art;
[16] FIG. 2 is a structural diagram of an ultrasonic gas flow meter according to an embodiment of the present invention; and
[17] FIG. 3 is a flow diagram illustrating an implementation of an embodiment of an ultrasonic gas flow meter according to an embodiment of the present invention.
[18] Description of symbols:
[19] a first flow velocity measurement channel transducer -1, a second flow velocity measurement channel transducer -2, a first sound velocity measurement channel transducer -3, a second sound velocity measurement channel transducer -4, and a flow measurement pipe -5.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[20] It is an object of the present invention to provide an ultrasonic gas flow meter, which enables a real-time check of a sound velocity of a gas, obtains a sound velocity value conforming to a theoretical sound velocity and a pulse signal corresponding thereto, and calculates the flow according to the principle of the transit time method, thereby ensuring the accuracy of flow metering.
[21] As shown in FIG. 2, the present invention provides an ultrasonic gas flow meter including: a flow measurement pipe 5, a first sound velocity measurement channel transducer 3, a second sound velocity measurement channel transducer 4, a first flow velocity measurement channel transducer 1, a second flow velocity measurement channel transducer 2, and a measurement control unit.
[22] A to-be-measured gas passes through the flow measurement pipe 5.
[23] The first sound velocity measurement channel transducer 3 is vertically mounted on the flow measurement pipe 5. The first sound velocity measurement channel transducer 3 is configured to transmit a first sonic signal, and the first sonic signal includes a plurality of first pulse signals.
[24] The second sound velocity measurement channel transducer 4 1s vertically mounted on the flow measurement pipe 5. The second sound velocity measurement channel transducer 4 corresponds to the first sound velocity measurement channel transducer 3 and is configured to receive the first sonic signal and transmit a second sonic signal. The first sound velocity measurement channel transducer 3 is further configured to receive the second sonic signal; and the second sonic signal includes a plurality of second pulse signals corresponding to the first pulse signals.
[25] A distance between the first sound velocity measurement channel transducer and the second sound velocity measurement channel transducer meets a preset condition, including: only one standard reference sound velocity existing within a theoretical sound velocity bandwidth range among the calculated sound velocity values of the plurality of first pulse signals and the plurality of second pulse signals. The distance between the first sound velocity measurement channel transducer and the second sound velocity measurement channel transducer is 1-2 cm.
[26] The first flow velocity measurement channel transducer 1 is mounted on the flow measurement pipe 5. The first flow velocity measurement channel transducer 1 is configured to transmit a downstream sonic signal, and the downstream sonic signal includes a plurality of downstream pulse signals.
[27] The second flow velocity measurement channel transducer 2 is mounted on the flow measurement pipe 5. The second flow velocity measurement channel transducer 2 is in central symmetry to the first flow velocity measurement channel transducer 1, and the second flow velocity measurement channel transducer 2 is configured to receive the downstream sonic signal and transmit an upstream sonic signal. The first flow velocity measurement channel transducer 1 is further configured to receive the upstream sonic signal; and the upstream sonic signal includes a plurality of upstream pulse signals corresponding to the downstream pulse signals.
[28] The measurement control unit is connected to the first sound velocity measurement channel transducer 3, the second sound velocity measurement channel transducer 4, the first flow velocity measurement channel transducer 1, and the second flow velocity measurement channel transducer 2. The measurement control unit is configured to: calculate a plurality of sound velocity values based on the first pulse signals and the second pulse signals corresponding thereto in the sound velocity measurement channel; compare the sound velocities with the sound velocity bandwidth range of the gas, and screen out only one sound velocity falling within the sound velocity bandwidth range of the gas which is recorded as a standard reference sound velocity;
calculate a plurality of sound velocity values based on downstream pulse signals and corresponding upstream pulse signals in the flow measurement channel; compare absolute values of differences between the sound velocities and the standard reference sound velocity with a set threshold, separately, screen out a sound velocity value with an absolute value less than the set threshold, and calculate an instantaneous flow based on a group of downstream pulse and upstream pulse corresponding to the sound velocity according to the principle of the transit time method.
[29] The distance between the first sound velocity measurement channel transducer 3 and the second sound velocity measurement channel transducer 4 is relatively short, which is 1-2 cm. Therefore, a signal can be stably received without getting easily affected, and the standard reference sound velocity can be detected in real time. The distance ensures that there is only one sound velocity meeting the condition within the theoretical sound velocity bandwidth range of the gas, which serves as a screening basis.
The two sound velocity measurement channel transducers are specifically configured to determine and correct positions of the ultrasonic received echoes of the first flow velocity measurement channel transducer 1 and the second flow velocity measurement channel transducer 2. When the ultrasonic signals are transmitted or received in a short distance within the sound velocity measurement channel, the echo intensity attenuation is small and the sound velocity difference between adjacent waves changes greatly. In view of such characteristics, a sonic position of a correct flight time can be clearly determined by using the sound velocity bandwidth range of the gas, i.e, a standard reference sound velocity is calculated by using its characteristics, and compared with sound velocity values of the flow measurement channel. The accuracy of sound velocities ensures the accuracy of flow metering, without the occurrence of a wrong determination.
[30] The first flow velocity measurement channel transducer 1 and the second flow velocity measurement channel transducer 2 have more than one calculated sound velocity value within the theoretical sound velocity bandwidth range of the gas.
Therefore, comparison and determination are performed with respect to a unique standard reference sound velocity to determine the echo pulse position and obtain upstream and downstream flight times, so as to calculate the flow according to the principle of the transit time method, thereby ensuring the metering accuracy.
[31] The first sound velocity measurement channel transducer 3, the second sound velocity measurement channel transducer 4, the first flow velocity measurement channel transducer 1, and the second flow velocity measurement channel transducer 2 are all 200
KHz ultrasonic transducers. The ultrasonic gas flow meter has a range of 1-180 nm’ / h 3 and an accuracy grade of 1.0.
[32] Further, the ultrasonic gas flow meter includes: a storage unit.
[33] The storage unit is connected to the measurement control unit. The storage unit is configured to store a current real-time sound velocity, and a downstream pulse signal, an upstream pulse signal, and an instantaneous flow corresponding thereto.
[34] The measurement control unit includes: a timing module and a control module.
[35] The timing module is connected to the first sound velocity measurement channel transducer 3, the second sound velocity measurement channel transducer 4, the first flow velocity measurement channel transducer 1, and the second flow velocity measurement channel transducer 2. The timing module is configured to obtain corresponding first flight times separately based on transmission times and the reception times of the first pulse signals; obtain corresponding second flight times based on transmission times and reception times of the second pulse signals; obtain corresponding downstream flight times based on transmission times and reception times of the downstream pulse signals; and obtain corresponding upstream flight times based on transmission times and reception times of the upstream pulse signals.
[36] The control module is connected to the timing module. The control module is configured to obtain a plurality of sound velocity values based on the first flight times and corresponding second flight times. A calculation formula for the sound velocity is as follows: . A 1 en cel)
[38] In the formula, L, is a distance between the first sound velocity measurement channel transducer 3 and the second sound velocity measurement channel transducer 4; {is an i” first flight time; and /, is an i second flight time.
[39] The control module calculates a plurality of sound velocities based on the first flight times and corresponding second flight times of the sound velocity measurement channel.
[40] A calculation formula for the sound velocity of the flow velocity measurement channel is as follows:
J /
[42] In the formula, C, is a j* sound velocity value; Z, is a distance between the first flow velocity measurement channel transducer 1 and the second flow velocity measurement channel transducer 2; f, is a j downstream flight time; and t, is a j" upstream flight time.
[43] The control module compares the sound velocities calculated in the sound velocity measurement channel with the theoretical sound velocity bandwidth range of the gas, and screens out only one sound velocity falling within the sound velocity bandwidth range of the gas which is recorded as a standard reference sound velocity; compares absolute values of differences between the sound velocities of the flow measurement channel and the standard reference sound velocity with a set threshold, separately, screens out a sound velocity value with an absolute value less than the set threshold, and calculates an instantaneous flow based on the flight time of the downstream pulse signal and the flight time of the upstream pulse signal corresponding to the sound velocity according to the principle of the transit time method.
[44] The control module uses an MS1030 chip.
[45] The control module is further configured to transmit a first control signal, a second control signal, a third control signal, and a fourth control signal to the first sound velocity measurement channel transducer 3, the second sound velocity measurement channel transducer 4, the first flow velocity measurement channel transducer 1, and the second flow velocity measurement channel transducer 2, respectively. The first sound velocity measurement channel transducer 3 is further configured to transmit a first sonic signal under control of the first control signal; the second sound velocity measurement channel transducer 4 is further configured to transmit a second sonic signal under control of the second control signal; the first flow velocity measurement channel transducer 1 is further configured to transmit a downstream sonic signal under control of the third control signal; and the second flow velocity measurement channel transducer 2 is further configured to transmit an upstream sonic signal under control of the fourth control signal.
[46] In addition, the ultrasonic gas flow meter further includes: a temperature and pressure collection unit.
[47] The temperature and pressure collection unit is mounted on the flow measurement pipe 5.
[48] As shown in FIG. 2, an embodiment is as follows.
[49] The temperature and pressure are collected by the temperature and pressure collection unit. The operations of the first sound velocity measurement channel transducer 3, the second sound velocity measurement channel transducer 4, the first flow velocity measurement channel transducer 1, and the second flow velocity measurement channel transducer 2 are controlled by the measurement control unit. A plurality of sound velocities of the sound velocity measurement channel and a plurality of sound velocities of the flow measurement channel are calculated. A unique standard reference sound velocity of the sound velocity measurement channel falling within the sound velocity bandwidth range of the gas is screened out based on the measurement control unit. Absolute values of differences between the sound velocities of the flow velocity measurement channel and the standard reference sound velocity are compared with a set threshold, separately. A sound velocity value with an absolute value less than the set threshold is screened out. Corresponding upstream and downstream flight times are obtained based on the sound velocity. An instantaneous flow is calculated according to the principle of the transit time method and a real-time sound velocity 1s outputted. In a particular embodiment, the set threshold is 0.5 m/s.

Claims (1)

ConclusiesConclusions 1. Ultrasone gasstromingsmeter omvattende: een stroommeetpijp waar een te meten gas doorheen gaat; een eerste geluidssnelheidsmeetkanaaltransducer die verticaal gemonteerd is op de stroommeetpijp en geconfigureerd is om een eerste sonisch signaal uit te zenden; waarbij het eerste sonische signaal een veelheid van eerste pulssignalen omvat; een tweede geluidssnelheidsmeetkanaaltransducer die verticaal gemonteerd is op de stroommeetpijp die overeenkomt met de eerste geluidssnelheidsmeetkanaaltransducer en geconfigureerd is om het eerste sonische signaal te ontvangen en een tweede sonische signaal uit te zenden; waarbij de eerste geluidssnelheidsmeetkanaaltransducer verder geconfigureerd is om het tweede sonische signaal te ontvangen; waarbij het tweede sonische signaal een veelheid van tweede pulssignalen omvat die overeenkomen met de eerste pulssignalen; een afstand tussen de eerste geluidssnelheidsmeetkanaaltransducer en de tweede geluidssnelheidsmeetkanaaltransducer die aan een vooraf ingestelde conditie voldoet, die het volgende omvat: slechts één standaardreferentiegeluidssnelheid die bestaat binnen een theoretisch geluidssnelheidsbandbreedtebereik onder de berekende geluidssnelheidswaarden van de veelheid van eerste pulssignalen en de veelheid van tweede pulssignalen; waarbij de afstand tussen de eerste geluidssnelheidsmeetkanaaltransducer en de tweede geluidssnelheidsmeetkanaaltransducer 1-2 cm is; een eerste stroomsnelheidsmeetkanaaltransducer die gemonteerd is op de stroommeetpijp en geconfigureerd is om een stroomafwaarts sonisch signaal uit te zenden; waarbij het stroomafwaartse sonische signaal een veelheid van stroomafwaartse pulssignalen omvat; en een tweede stroomsnelheidsmeetkanaaltransducer die op de stroommeetpijp gemonteerd is in centrale symmetrie ten opzichte van de eerste stroomsnelheidsmeetkanaaltransducer en geconfigureerd is om het stroomafwaartse sonische signaal te ontvangen en een stroomopwaarts sonisch signaal uit te zenden; waarbij de eerste stroomsnelheidsmeetkanaaltransducer verder geconfigureerd is om het stroomopwaartse sonische signaal te ontvangen; waarbij het stroomopwaartse sonische signaal een veelheid van stroomopwaartse pulssignalen omvat die overeenkomen met de stroomafwaartse pulssignalen.1. An ultrasonic gas flowmeter comprising: a flow measuring pipe through which a gas to be measured passes; a first sonic velocity measuring channel transducer vertically mounted on the flow measuring pipe and configured to emit a first sonic signal; wherein the first sonic signal comprises a plurality of first pulse signals; a second sonic velocity measuring channel transducer vertically mounted on the flow measuring pipe corresponding to the first sonic velocity measuring channel transducer and configured to receive the first sonic signal and emit a second sonic signal; wherein the first sonic velocity measuring channel transducer is further configured to receive the second sonic signal; wherein the second sonic signal comprises a plurality of second pulse signals corresponding to the first pulse signals; a distance between the first sound velocity measurement channel transducer and the second sound velocity measurement channel transducer satisfying a preset condition, comprising: only one standard reference sound velocity existing within a theoretical sound velocity bandwidth range among the calculated sound velocity values of the plurality of first pulse signals and the plurality of second pulse signals; wherein the distance between the first sound velocity measurement channel transducer and the second sound velocity measurement channel transducer is 1-2 cm; a first flow velocity measurement channel transducer mounted on the flow measuring pipe and configured to transmit a downstream sonic signal; wherein the downstream sonic signal comprises a plurality of downstream pulse signals; and a second flow velocity measurement channel transducer mounted on the flow measuring pipe in central symmetry with respect to the first flow velocity measurement channel transducer and configured to receive the downstream sonic signal and transmit an upstream sonic signal; wherein the first flow velocity measurement channel transducer is further configured to receive the upstream sonic signal; wherein the upstream sonic signal comprises a plurality of upstream pulse signals corresponding to the downstream pulse signals.
NL2036070A 2023-10-19 2023-10-19 Ultrasonic gas flow meter NL2036070B1 (en)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3727454A (en) * 1970-02-27 1973-04-17 Thomson Csf Ultrasonic systems for carrying out flow measurements in fluids
EP1094305A2 (en) * 1992-10-06 2001-04-25 Caldon, Inc. Apparatus for determining fluid flow
EP1624300A1 (en) * 2004-08-04 2006-02-08 Flotec UK Limited Ultrasonic fluid analysis cell with travel time measurement

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3727454A (en) * 1970-02-27 1973-04-17 Thomson Csf Ultrasonic systems for carrying out flow measurements in fluids
EP1094305A2 (en) * 1992-10-06 2001-04-25 Caldon, Inc. Apparatus for determining fluid flow
EP1624300A1 (en) * 2004-08-04 2006-02-08 Flotec UK Limited Ultrasonic fluid analysis cell with travel time measurement

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