CA2188145A1 - Acoustic flow measurement method and measurement apparatus implementing the method - Google Patents

Acoustic flow measurement method and measurement apparatus implementing the method

Info

Publication number
CA2188145A1
CA2188145A1 CA002188145A CA2188145A CA2188145A1 CA 2188145 A1 CA2188145 A1 CA 2188145A1 CA 002188145 A CA002188145 A CA 002188145A CA 2188145 A CA2188145 A CA 2188145A CA 2188145 A1 CA2188145 A1 CA 2188145A1
Authority
CA
Canada
Prior art keywords
measurement
downstream
upstream
acoustic
measurement pipe
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CA002188145A
Other languages
French (fr)
Other versions
CA2188145C (en
Inventor
Pekka Hiismaki
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Valtion Teknillinen Tutkimuskeskus
Original Assignee
Pekka Hiismaki
Valtion Teknillinen Tutkimuskeskus
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Pekka Hiismaki, Valtion Teknillinen Tutkimuskeskus filed Critical Pekka Hiismaki
Publication of CA2188145A1 publication Critical patent/CA2188145A1/en
Application granted granted Critical
Publication of CA2188145C publication Critical patent/CA2188145C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/66—Measuring 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
    • G01F1/667—Arrangements of transducers for ultrasonic flowmeters; Circuits for operating ultrasonic flowmeters
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/66—Measuring 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
    • G01F1/662—Constructional details
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/66—Measuring 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
    • G01F1/667—Arrangements of transducers for ultrasonic flowmeters; Circuits for operating ultrasonic flowmeters
    • G01F1/668—Compensating or correcting for variations in velocity of sound
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P5/00—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft
    • G01P5/24—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring the direct influence of the streaming fluid on the properties of a detecting acoustical wave
    • G01P5/245—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring the direct influence of the streaming fluid on the properties of a detecting acoustical wave by measuring transit time of acoustical waves

Abstract

The present invention relates to an acoustic measurement method of low measurement for the determination of fluid flow velocity (v), volumetric flow (Q) and/or mass flow rate (M) in a measurement pipe section (1) by way of determining over an exactly determined length (~a~b) the downstream propagation time TD and upstream propagation time TU for naturally occurring and/or artificially generated acoustic wave modes (15, 16) propagating upstream and downstream in a measurement pipe (1) section in the form of plane wavefronts at a low frequency. The pairwise opposed transducers (11, 12; 13, 14) mounted on the measurement pipe section (1) are configured by delaying, scaling and summing of the signals into at least two direction-discriminating filters of which one eliminates signals related to downstream acoustic waves while the other eliminates signals related to the upstream acoustic waves in the measurement pipe section (1). The output signals of direction-discriminating filters performing filtering in the same direction are compared with each other by forming a symmetrical equilibrium function with respect to their delay variable from a) the cross correlation function, b) the time integral of the squared difference, or c) the time integral of the squared sum, of the output signals, whereby one of the listed alternative functions is computed for acoustic waves in both downstream and upstream directions. These equilibrium functions are maximally symmetrical with respect to their maxima or minima when the direction-discriminating filtering is made properly and the correct values of the acoustic wavefront propagation times TD and TU for use in the computation of both the measurement result (v, c, Q and/or M) given by the method and the values of the delay time variables employed in the direction-discriminating filters are determined from these, maximally symmetrical equilibrium functions with the help of a certain, predetermined algorithm.
CA002188145A 1994-04-19 1995-03-29 Acoustic flow measurement method and measurement apparatus implementing the method Expired - Fee Related CA2188145C (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FI941805A FI94909C (en) 1994-04-19 1994-04-19 Acoustic flow measurement method and applicable device
FI941805 1994-04-19
PCT/FI1995/000168 WO1995028619A1 (en) 1994-04-19 1995-03-29 Acoustic flow measurement method and measurement apparatus implementing the method

Publications (2)

Publication Number Publication Date
CA2188145A1 true CA2188145A1 (en) 1995-10-26
CA2188145C CA2188145C (en) 2005-03-22

Family

ID=8540553

Family Applications (1)

Application Number Title Priority Date Filing Date
CA002188145A Expired - Fee Related CA2188145C (en) 1994-04-19 1995-03-29 Acoustic flow measurement method and measurement apparatus implementing the method

Country Status (7)

Country Link
US (1) US5770806A (en)
EP (1) EP0756697B1 (en)
AT (1) ATE240505T1 (en)
CA (1) CA2188145C (en)
DE (1) DE69530764T2 (en)
FI (1) FI94909C (en)
WO (1) WO1995028619A1 (en)

Families Citing this family (104)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19611233A1 (en) * 1996-03-21 1997-09-25 Siemens Ag Procedure for measuring the transit time of an electrical, electromagnetic or acoustic signal
AUPQ061399A0 (en) * 1999-05-27 1999-06-17 University Of Sydney, The Acoustic flow meters
US6579751B2 (en) * 1999-09-01 2003-06-17 Micron Technology, Inc. Semiconductor processing methods of forming integrated circuitry
SE0003348D0 (en) * 2000-09-18 2000-09-18 Flaekt Ab Apparatus and method for measuring the flow in a fluid
US6587798B2 (en) * 2000-12-04 2003-07-01 Weatherford/Lamb, Inc. Method and system for determining the speed of sound in a fluid within a conduit
KR100943874B1 (en) * 2001-01-22 2010-02-24 데이진 가부시키가이샤 Equipment and method for measuring concentration and flow rate of gas ultrasonically
US7328624B2 (en) * 2002-01-23 2008-02-12 Cidra Corporation Probe for measuring parameters of a flowing fluid and/or multiphase mixture
US7032432B2 (en) * 2002-01-23 2006-04-25 Cidra Corporation Apparatus and method for measuring parameters of a mixture having liquid droplets suspended in a vapor flowing in a pipe
US7275421B2 (en) * 2002-01-23 2007-10-02 Cidra Corporation Apparatus and method for measuring parameters of a mixture having solid particles suspended in a fluid flowing in a pipe
US7359803B2 (en) * 2002-01-23 2008-04-15 Cidra Corporation Apparatus and method for measuring parameters of a mixture having solid particles suspended in a fluid flowing in a pipe
WO2004015377A2 (en) * 2002-08-08 2004-02-19 Cidra Corporation Apparatus and method for measuring multi-phase flows in pulp and paper industry applications
CA2513105C (en) * 2002-11-12 2013-01-08 Cidra Corporation An apparatus having an array of piezoelectric film sensors for measuring parameters of a process flow within a pipe
US7165464B2 (en) * 2002-11-15 2007-01-23 Cidra Corporation Apparatus and method for providing a flow measurement compensated for entrained gas
WO2004048906A2 (en) * 2002-11-22 2004-06-10 Cidra Corporation Method for calibrating a flow meter having an array of sensors
US7096719B2 (en) * 2003-01-13 2006-08-29 Cidra Corporation Apparatus for measuring parameters of a flowing multiphase mixture
WO2004063675A2 (en) * 2003-01-13 2004-07-29 Cidra Corporation Apparatus and method using an array of ultrasonic sensors for determining the velocity of a fluid within a pipe
US7058549B2 (en) * 2003-01-21 2006-06-06 C1Dra Corporation Apparatus and method for measuring unsteady pressures within a large diameter pipe
US7343818B2 (en) * 2003-01-21 2008-03-18 Cidra Corporation Apparatus and method of measuring gas volume fraction of a fluid flowing within a pipe
US20060048583A1 (en) * 2004-08-16 2006-03-09 Gysling Daniel L Total gas meter using speed of sound and velocity measurements
EP1590637B1 (en) * 2003-01-21 2008-11-05 Expro Meters, Inc. An apparatus and method of measuring gas volume fraction of a fluid flowing within a pipe
CA2514696C (en) 2003-01-21 2012-12-11 Cidra Corporation Measurement of entrained and dissolved gases in process flow lines
EP1599705B1 (en) 2003-03-04 2019-01-02 CiDra Corporation An apparatus having a multi-band sensor assembly for measuring a parameter of a fluid flow flowing within a pipe
ES2239874B2 (en) * 2003-03-27 2007-05-01 Centro De Investigaciones Energeticas Medioambientales Y Tecnologicas (C.I.E.M.A.T.) METHOD OF DESIGN, EVALUATION AND OPTIMIZATION OF SYSTEMS BASED ON TRANSMISSION OF PULSED SIGNALS OF ULTRASOUNDS, INTENDED FOR THE CHARACTERIZATION OF FLOWS.
US6745632B1 (en) * 2003-06-03 2004-06-08 Joseph Ernest Dryer Method for measuring ultrasonic transit times
EP1631797A2 (en) * 2003-06-05 2006-03-08 CiDra Corporation Apparatus for measuring velocity and flow rate of a fluid having a non-negligible axial mach number using an array of sensors
US7121152B2 (en) * 2003-06-06 2006-10-17 Cidra Corporation Portable flow measurement apparatus having an array of sensors
US20050050956A1 (en) * 2003-06-24 2005-03-10 Gysling Daniel L. Contact-based transducers for characterizing unsteady pressures in pipes
US7197938B2 (en) * 2003-06-24 2007-04-03 Cidra Corporation Contact-based transducers for characterizing unsteady pressures in pipes
US7245385B2 (en) * 2003-06-24 2007-07-17 Cidra Corporation Characterizing unsteady pressures in pipes using optical measurement devices
CA2530596C (en) * 2003-06-24 2013-05-21 Cidra Corporation System and method for operating a flow process
US7150202B2 (en) * 2003-07-08 2006-12-19 Cidra Corporation Method and apparatus for measuring characteristics of core-annular flow
US7134320B2 (en) * 2003-07-15 2006-11-14 Cidra Corporation Apparatus and method for providing a density measurement augmented for entrained gas
WO2005010468A2 (en) * 2003-07-15 2005-02-03 Cidra Corporation A configurable multi-function flow measurement apparatus having an array of sensors
US7152460B2 (en) * 2003-07-15 2006-12-26 Cidra Corporation Apparatus and method for compensating a coriolis meter
WO2005010469A2 (en) * 2003-07-15 2005-02-03 Cidra Corporation A dual function flow measurement apparatus having an array of sensors
US7299705B2 (en) * 2003-07-15 2007-11-27 Cidra Corporation Apparatus and method for augmenting a Coriolis meter
US7882750B2 (en) * 2003-08-01 2011-02-08 Cidra Corporate Services, Inc. Method and apparatus for measuring parameters of a fluid flowing within a pipe using a configurable array of sensors
US7322251B2 (en) * 2003-08-01 2008-01-29 Cidra Corporation Method and apparatus for measuring a parameter of a high temperature fluid flowing within a pipe using an array of piezoelectric based flow sensors
WO2005012843A2 (en) 2003-08-01 2005-02-10 Cidra Corporation Method and apparatus for measuring parameters of a fluid flowing within a pipe using a configurable array of sensors
WO2005015135A2 (en) * 2003-08-08 2005-02-17 Cidra Corporation Piezocable based sensor for measuring unsteady pressures inside a pipe
US7110893B2 (en) * 2003-10-09 2006-09-19 Cidra Corporation Method and apparatus for measuring a parameter of a fluid flowing within a pipe using an array of sensors
US7237440B2 (en) * 2003-10-10 2007-07-03 Cidra Corporation Flow measurement apparatus having strain-based sensors and ultrasonic sensors
US7274996B2 (en) 2003-10-20 2007-09-25 Genscape Intangible Holding, Inc. Method and system for monitoring fluid flow
US7171315B2 (en) * 2003-11-25 2007-01-30 Cidra Corporation Method and apparatus for measuring a parameter of a fluid flowing within a pipe using sub-array processing
WO2005059479A1 (en) * 2003-12-11 2005-06-30 Cidra Corporation Method and apparatus for determining a quality metric of a measurement of a fluid parameter
US7330797B2 (en) * 2004-03-10 2008-02-12 Cidra Corporation Apparatus and method for measuring settlement of solids in a multiphase flow
WO2005088262A2 (en) * 2004-03-10 2005-09-22 Cidra Corporation Method and apparatus for measuring parameters of a stratified flow
US7367239B2 (en) * 2004-03-23 2008-05-06 Cidra Corporation Piezocable based sensor for measuring unsteady pressures inside a pipe
US7426852B1 (en) 2004-04-26 2008-09-23 Expro Meters, Inc. Submersible meter for measuring a parameter of gas hold-up of a fluid
CA2568349C (en) * 2004-05-17 2013-07-16 Cidra Corporation Apparatus and method for measuring compositional parameters of a mixture
WO2006112878A2 (en) 2004-09-16 2006-10-26 Cidra Corporation Apparatus and method for providing a fluid cut measurement of a multi-liquid mixture compensated for entrained gas
US7389687B2 (en) * 2004-11-05 2008-06-24 Cidra Corporation System for measuring a parameter of an aerated multi-phase mixture flowing in a pipe
US7561203B2 (en) * 2005-01-10 2009-07-14 Nokia Corporation User input device
US7962293B2 (en) * 2005-03-10 2011-06-14 Expro Meters, Inc. Apparatus and method for providing a stratification metric of a multiphase fluid flowing within a pipe
WO2010120258A2 (en) * 2005-03-17 2010-10-21 Cidra Corporation An apparatus and method of processing data to improve the performance of a flow monitoring system
US7657392B2 (en) * 2005-05-16 2010-02-02 Cidra Corporate Services, Inc. Method and apparatus for detecting and characterizing particles in a multiphase fluid
US7526966B2 (en) * 2005-05-27 2009-05-05 Expro Meters, Inc. Apparatus and method for measuring a parameter of a multiphase flow
WO2006130499A2 (en) * 2005-05-27 2006-12-07 Cidra Corporation An apparatus and method for fiscal measuring of an aerated fluid
WO2006134199A1 (en) * 2005-06-16 2006-12-21 Justiflow Oy Ultrasound flowmeter arrangement for determining speed of sound
US7249525B1 (en) 2005-06-22 2007-07-31 Cidra Corporation Apparatus for measuring parameters of a fluid in a lined pipe
EP1899686B1 (en) * 2005-07-07 2011-09-28 CiDra Corporation Wet gas metering using a differential pressure based flow meter with a sonar based flow meter
US7603916B2 (en) * 2005-07-07 2009-10-20 Expro Meters, Inc. Wet gas metering using a differential pressure and a sonar based flow meter
WO2007009097A1 (en) * 2005-07-13 2007-01-18 Cidra Corporation Method and apparatus for measuring parameters of a fluid flow using an array of sensors
US7152490B1 (en) * 2005-08-15 2006-12-26 Daniel Measurement And Control, Inc. Methods for determining transducer delay time and transducer separation in ultrasonic flow meters
US20070055464A1 (en) * 2005-08-17 2007-03-08 Gysling Daniel L System and method for providing a compositional measurement of a mixture having entrained gas
US8616064B2 (en) 2006-04-21 2013-12-31 Kulite Semiconductor Products, Inc. Combination static and dynamic pressure transducer employing a micro-filter
US7975552B2 (en) * 2006-04-21 2011-07-12 Kulite Semiconductor Products, Inc. Pressure transducer employing a micro-filter and emulating an infinite tube pressure transducer
US7484415B2 (en) * 2006-04-21 2009-02-03 Kulite Semiconductor Products, Inc. Pressure transducer employing a micro-filter and emulating an infinite tube pressure transducer
US7454981B2 (en) * 2006-05-16 2008-11-25 Expro Meters. Inc. Apparatus and method for determining a parameter in a wet gas flow
US7624650B2 (en) 2006-07-27 2009-12-01 Expro Meters, Inc. Apparatus and method for attenuating acoustic waves propagating within a pipe wall
US7624651B2 (en) * 2006-10-30 2009-12-01 Expro Meters, Inc. Apparatus and method for attenuating acoustic waves in pipe walls for clamp-on ultrasonic flow meter
US7673526B2 (en) * 2006-11-01 2010-03-09 Expro Meters, Inc. Apparatus and method of lensing an ultrasonic beam for an ultrasonic flow meter
EP2092278A2 (en) 2006-11-09 2009-08-26 Expro Meters, Inc. Apparatus and method for measuring a fluid flow parameter within an internal passage of an elongated body
US8240636B2 (en) 2009-01-12 2012-08-14 Fresenius Medical Care Holdings, Inc. Valve system
US8105487B2 (en) 2007-09-25 2012-01-31 Fresenius Medical Care Holdings, Inc. Manifolds for use in conducting dialysis
US9199022B2 (en) 2008-09-12 2015-12-01 Fresenius Medical Care Holdings, Inc. Modular reservoir assembly for a hemodialysis and hemofiltration system
US9308307B2 (en) 2007-09-13 2016-04-12 Fresenius Medical Care Holdings, Inc. Manifold diaphragms
US8597505B2 (en) 2007-09-13 2013-12-03 Fresenius Medical Care Holdings, Inc. Portable dialysis machine
US9358331B2 (en) 2007-09-13 2016-06-07 Fresenius Medical Care Holdings, Inc. Portable dialysis machine with improved reservoir heating system
CA2960103C (en) 2007-11-29 2020-03-10 Fredenius Medical Care Holdings, Inc. System and method for conducting hemodialysis and hemofiltration
US8061186B2 (en) 2008-03-26 2011-11-22 Expro Meters, Inc. System and method for providing a compositional measurement of a mixture having entrained gas
WO2010042667A2 (en) 2008-10-07 2010-04-15 Xcorporeal, Inc. Thermal flow meter
EP2334412B1 (en) 2008-10-07 2019-08-21 Fresenius Medical Care Holdings, Inc. Priming system and method for dialysis systems
EP2342003B1 (en) 2008-10-30 2018-09-26 Fresenius Medical Care Holdings, Inc. Modular, portable dialysis system
CN102830245A (en) * 2012-08-15 2012-12-19 华北电力大学 Monitoring system and monitoring method for boiler furnace flue gas velocity based on acoustics
US9201036B2 (en) 2012-12-21 2015-12-01 Fresenius Medical Care Holdings, Inc. Method and system of monitoring electrolyte levels and composition using capacitance or induction
US9157786B2 (en) 2012-12-24 2015-10-13 Fresenius Medical Care Holdings, Inc. Load suspension and weighing system for a dialysis machine reservoir
US9354640B2 (en) * 2013-11-11 2016-05-31 Fresenius Medical Care Holdings, Inc. Smart actuator for valve
US20170275986A1 (en) * 2015-11-05 2017-09-28 Halliburton Energy Services Inc. Fluid flow metering with point sensing
GB2570131A (en) * 2018-01-11 2019-07-17 Imperial Innovations Ltd Fluid flow analysis
CN108828057A (en) * 2018-06-26 2018-11-16 西安石油大学 A kind of oil-water two-phase flow Multi-parameter detection device and method based on electromagnetism acoustical coupling
US11231311B2 (en) 2019-05-31 2022-01-25 Perceptive Sensor Technologies Llc Non-linear ultrasound method and apparatus for quantitative detection of materials
CA3140008C (en) * 2019-05-31 2022-10-04 James M. Heim Non-linear ultrasound method and apparatus for quantitative detection of materials (liquids, gas, plasma)
US11729537B2 (en) 2020-12-02 2023-08-15 Perceptive Sensor Technologies, Inc. Variable angle transducer interface block
US11549839B2 (en) 2020-12-04 2023-01-10 Perceptive Sensor Technologies, Inc. Systems and methods for determining floating roof level tilt and characterizing runoff
EP4256296A1 (en) 2020-12-04 2023-10-11 Perceptive Sensor Technologies, Inc. Acoustic temperature measurement in layered environments
US11585690B2 (en) 2020-12-04 2023-02-21 Perceptive Sensor Technologies, Inc. Multi-path acoustic signal improvement for material detection
US11788904B2 (en) 2020-12-04 2023-10-17 Perceptive Sensor Technologies, Inc. Acoustic temperature measurement in layered environments
WO2022120265A1 (en) 2020-12-04 2022-06-09 Perceptive Sensor Technologies, Inc. In-wall multi-bounce material property detection and acoustic signal amplification
CA3201086A1 (en) 2020-12-04 2022-06-09 Lazar Bivolarsky Apparatus, system, and method for the detection of objects and activity within a container
US11604294B2 (en) 2020-12-04 2023-03-14 Perceptive Sensor Technologies, Inc. Determining layer characteristics in multi-layered environments
CN116888468A (en) 2020-12-30 2023-10-13 感知传感器技术股份有限公司 Signal assessment of fluid quality
WO2023154514A1 (en) 2022-02-11 2023-08-17 Perceptive Sensor Technologies, Inc. Acoustic signal detection of material composition in static and dynamic conditions
US11940420B2 (en) 2022-07-19 2024-03-26 Perceptive Sensor Technologies, Inc. Acoustic signal material identification with nanotube couplant

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4011755A (en) * 1975-10-23 1977-03-15 Panametrics, Inc. Acoustic flowmeter
US4445389A (en) * 1981-09-10 1984-05-01 The United States Of America As Represented By The Secretary Of Commerce Long wavelength acoustic flowmeter
NL8602690A (en) * 1986-10-27 1988-05-16 Servex Bv DEVICE FOR DETERMINING THE FLOW RATE OF A MEDIUM IN A CYLINDRICAL PIPE.
US5152174A (en) * 1990-09-24 1992-10-06 Labudde Edward V Mass flow rate sensor and method
US5437194A (en) * 1991-03-18 1995-08-01 Panametrics, Inc. Ultrasonic transducer system with temporal crosstalk isolation
US5228347A (en) * 1991-10-18 1993-07-20 Ore International, Inc. Method and apparatus for measuring flow by using phase advance
FI91106C (en) * 1991-12-23 1994-05-10 Kytoelae Instrumenttitehdas Method and apparatus for monitoring gas flow, especially natural gas flow
FI87493C (en) * 1991-12-23 1993-01-11 Kytoelae Instrumenttitehdas OVER ANCHORING FOR OVER MAINTENANCE AV STROEMNINGSHASTIGHETEN AV GASER OCH / ELLER STORHETER SOM KAN HAERLEDAS FRAON DENNA
FI88208C (en) * 1992-04-01 1993-04-13 Valtion Teknillinen FARING EQUIPMENT FOR ACOUSTIC MAINTENANCE AV ENTRY
FI88209C (en) * 1992-04-14 1993-04-13 Kytoelae Instrumenttitehdas Method and apparatus for acoustic current measurement to assure the performance

Also Published As

Publication number Publication date
FI94909B (en) 1995-07-31
US5770806A (en) 1998-06-23
EP0756697A1 (en) 1997-02-05
DE69530764T2 (en) 2004-02-19
ATE240505T1 (en) 2003-05-15
DE69530764D1 (en) 2003-06-18
FI941805A0 (en) 1994-04-19
CA2188145C (en) 2005-03-22
EP0756697B1 (en) 2003-05-14
FI94909C (en) 1995-11-10
WO1995028619A1 (en) 1995-10-26

Similar Documents

Publication Publication Date Title
CA2188145A1 (en) Acoustic flow measurement method and measurement apparatus implementing the method
KR100349504B1 (en) Ultrasonic flow velocity measuring apparatus
EP0572583B1 (en) Method and device for measurement of the flow velocities of gases and/or of quantities that can be derived from same
US5421212A (en) Method and device in acoustic flow measurement for ensuring the operability of said measurement
EP0572581B1 (en) Method and device for monitoring of a gas flow, in particular a natural-gas flow
Agarwal et al. Acoustic wave propagation in a pipe with fully developed turbulent flow
FI89835B (en) Method and device for determining the speed of a gas flowing in a pipe
Holmer et al. Transmission of sound through pipe walls in the presence of flow
WO1994009342A1 (en) Acoustic flowmeter
JPH02107924A (en) Two-phase flow ultrasonic type flow rate measuring method and apparatus
Redwood Ultrasonic waveguides—a physical approach
JP3438371B2 (en) Flow measurement device
JPH08313316A (en) Ultrasonic wave type flow meter
SU1030656A1 (en) Ultrasonic flowmeter
CA2658849A1 (en) Apparatus and method for attenuating acoustic waves in propagating within a pipe wall
Eccardt et al. Simulation of acoustic wave propagation within flowing media using simplified boundary element techniques
Froysa et al. A ray theory approach to investigate the influence of flow velocity profiles on transit times in ultrasonic flow meters for gas and liquid
Vigran Measuring the acoustic properties of ducts
SU1374069A1 (en) Method of determining acoustic characteristics of exhaust system elements of internal combustion engine
Selamet et al. Effect of expansion chamber on the resonance frequency of side branches and Herschel-Quincke tubes
Chaitanya et al. Experimental validation of the 1-D acoustical model for conical concentric tube resonators with moving medium
JPH1144561A (en) Ultrasonic flow rate and flow velocity meter
Martin Noise control in hydraulic systems
Harris On the generation of pipeline acoustic resonance
Yamazaki et al. Estimation of Mach Number of Shock Wave Propagating in Pipe

Legal Events

Date Code Title Description
EEER Examination request
MKLA Lapsed

Effective date: 20130402