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WO2000039537A1 - Capteur d'ecoulement fluidique - Google Patents

Capteur d'ecoulement fluidique Download PDF

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Publication number
WO2000039537A1
WO2000039537A1 PCT/US1999/030661 US9930661W WO0039537A1 WO 2000039537 A1 WO2000039537 A1 WO 2000039537A1 US 9930661 W US9930661 W US 9930661W WO 0039537 A1 WO0039537 A1 WO 0039537A1
Authority
WO
WIPO (PCT)
Prior art keywords
fluid flow
sensor
piezoresistive material
piezoresistive
resistance
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.)
Ceased
Application number
PCT/US1999/030661
Other languages
English (en)
Inventor
Athanasios J. Syllaios
Dipankar Chandra
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.)
Raytheon Co
Original Assignee
Raytheon Co
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 Raytheon Co filed Critical Raytheon Co
Priority to AU22091/00A priority Critical patent/AU2209100A/en
Publication of WO2000039537A1 publication Critical patent/WO2000039537A1/fr
Anticipated expiration legal-status Critical
Ceased 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
    • G01F1/05—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 using mechanical effects
    • G01F1/20—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 using mechanical effects by detection of dynamic effects of the flow
    • G01F1/28—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 using mechanical effects by detection of dynamic effects of the flow by drag-force, e.g. vane type or impact flowmeter
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P13/00—Indicating or recording presence, absence, or direction, of movement
    • G01P13/0006—Indicating or recording presence, absence, or direction, of movement of fluids or of granulous or powder-like substances
    • G01P13/0026—Indicating or recording presence, absence, or direction, of movement of fluids or of granulous or powder-like substances by using deflection of baffle-plates
    • G01P13/0033—Indicating or recording presence, absence, or direction, of movement of fluids or of granulous or powder-like substances by using deflection of baffle-plates with electrical coupling to the indicating device
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
    • G01P13/00—Indicating or recording presence, absence, or direction, of movement
    • G01P13/02—Indicating direction only, e.g. by weather vane

Definitions

  • This invention relates generally to sensors and more particularly to a fluid flow sensor.
  • the present invention provides a fluid flow sensor that provides these features .
  • a micro-electromechanical fluid flow sensor for measuring the magnitude and direction of a fluid flow.
  • the sensor includes a piezoresistive material that is exposed to the fluid flow. When the piezoresistive material is so exposed, the fluid flow applies a force to the piezoresistive material. In response to this force, the resistance of the piezoresistive material may change.
  • the fluid flow sensor further includes an electrical circuit coupled to the piezoresistive material. The electrical circuit measures any change in resistance of the piezoresistive material in response to exposure to the fluid flow. The measured change in resistance may then be correlated with a high degree of accuracy and reliability to a certain magnitude and/or direction of the fluid flow.
  • sensors incorporating teachings of the present invention exhibit relatively high sensitivity and accuracy.
  • such sensors exhibit a large dynamic range.
  • a large dynamic range indicates the ability of a sensor to measure small as well as large flow rates.
  • Another technical advantage of sensors incorporating teachings of the present invention includes the ability to sense gas, liquid, and multiphase fluid flows.
  • sensors incorporating the present invention may have an "open" structure allowing them to sense flows from any direction.
  • Sensors incorporating teachings of the present invention may also be relatively small in size. Because of this small size, such sensors may be used in microenvironments such as micro-electromechanical systems (MEMS) or microfluidic systems. Furthermore, sensors incorporating the present invention can detect rapid changes in flow rates due to their high frequency response. Other technical advantages are readily apparent to one skilled in the art from the following figures, descriptions, and claims.
  • FIGURE 1 is a schematic drawing showing a sensor incorporating teachings of the present invention
  • FIGURE 2 is a schematic drawing in elevation showing the sensor of FIGURE 1 in a deflected position
  • FIGURE 3 is a schematic drawing showing a plan view of a sensing system for measuring fluid flow in accordance with teachings of the present invention
  • FIGURE 4 is a schematic drawing of sensing system for measuring fluid flow representing another embodiment of the present invention.
  • FIGURE 5 is a schematic drawing of the sensor of FIGURE 1, configured for measuring the magnitude of a fluid flow
  • FIGURE 6 is a schematic drawing showing two sensors as shown in FIGURE 1, configured for measuring the direction of a fluid flow.
  • FIGURE 1 is a schematic drawing showing sensor 10 incorporating teachings of the present invention.
  • Sensor 10 preferably includes at least two components, layer 20 comprising a selected piezoresistive type material and support medium 30.
  • Layer 20 is preferably formed from piezoresistive material, which experiences a change in bulk resistance to electrical current flow when stress is applied to it. Examples of piezoresistive materials satisfactory for use with the present invention include silicon doped with either phosphorus or boron.
  • support medium for the embodiment shown in FIGURE 1, support medium
  • Selected piezoresistive material may be layered on or implanted in support medium 30 to form layer 20.
  • support medium 30 may be made from silicon.
  • Piezoresistive layer or layers 20 may be formed by implanting boron and/or phosphorus in certain regions of support medium 30 to provide one or more layers 20.
  • selected piezoresistive material may be placed on top of support medium 30. In other embodiments of the present invention, piezoresistive material may stand alone without a support medium 30.
  • Sensor 10 can be used to detect and measure various types of fluid flows, including gas, liquid, and multiple phase fluid flows.
  • the term "multiple phase fluid” is used to describe a fluid flow having various combinations of gas, liquid and/or particulate matter.
  • a sensor incorporating teachings of the present invention may be satisfactorily used to accurately measure fluid flow in industrial applications having a mixture of gas, liquid and particulate matter.
  • Sensor 10 is shown in FIGURE 1 in an undeflected position, as it would appear without the force of a fluid flow acting upon it.
  • Sensor 10 is shown in FIGURE 2 at a deflected position due to the force of fluid flow therepast .
  • Portions of sensor 10 comprising piezoresistive layer 20 and support medium 30 will deflect as a result of force applied by the fluid flow.
  • stress is applied to piezoresistive layer 20. Due to this applied stress, the resistance of piezoresistive layer 20 may change. Any change in resistance may then be measured using an electrical circuit (not explicitly shown in FIGURE 2) .
  • the change in resistance may be used to determine the magnitude of the fluid flow.
  • Multiple sensors 10 may be used to indicate the direction of the fluid flow.
  • sensor 10 is shown in a deflected position, the force applied by the fluid flow to piezoresistive layer 20 does not have to create a visible deflection of sensor 10. In order to measure the fluid flow, the flow need only apply enough force to sensor 10 to create a resistance change in piezoresistive layer 20.
  • piezoresistive layer 20 in FIGURES 1 and 2 is only one example of many different possible configurations. Piezoresistive layer 20 may not cover the entire surface of support medium 30. In fact, such a configuration may not be desired for some applications. Piezoresistive material is preferably placed in selected areas based on anticipated stresses induced by the fluid flow and characteristics of the associated support medium 30. For instance, piezoresistive material may be placed at locations on support medium 30 where the applied stress is expected to be maximized.
  • sensor 10 incorporates a cantilevered beam design
  • a sensor incorporating the present invention is not limited to such a design.
  • Other sensors incorporating teachings of the present invention may include a beam supported in any fashion and at any number of locations.
  • the associated support medium does not have to be a beam.
  • a support medium may comprise a membrane placed in the fluid flow.
  • a sensor incorporating teachings of the present invention may not include a support medium.
  • the piezoresistive material may stand alone in any desired configuration. Referring now to FIGURE 3, a double beam cantilever shape may be employed as support medium 30a in sensor 12 incorporating teachings of the present invention.
  • support medium 30a includes a generally "U"- shaped beam having legs 32a and 32b. An electrical current directed into leg 32a will flow out of leg 32b, or the reverse.
  • piezoresistive layer 20 may cover one entire exterior surface of support medium 30a. But as discussed above, piezoresistive material may be placed only at selected portions of support medium 30a. A fluid flow is measured by coupling piezoresistive layer 20 to electrical circuit 40. Electrical circuit 40 may be connected to piezoresistive layer 20 through electrical leads 42. In addition, wires 44 of electrical circuit 40 that are coupled to piezoresistive layer 20 may be supported by one or more bonding pads 46.
  • the current flowing through piezoresistive layer 20 into electrical circuit 40 may be used to measure the change in resistance of piezoresistive layer 20.
  • the magnitude and sign (positive or negative) of this change in resistance may be correlated to a magnitude and sign of the fluid flow.
  • any type of electrical circuit capable of measuring a change in resistance may be used in conjunction with piezoresistive layer 20. It should be noted that the "U"- shaped configuration of support medium 30a is not required. The electrical current may be directed by other geometrical configurations, or the current by be conducted through the use of electrical wiring running through piezoresistive layer 20.
  • FIGURE 4 shows sensing system 100 incorporating teachings of the present invention.
  • Sensing system 100 comprises two cantilevered beams, signal beam 110 and reference beam 120.
  • beams 110 and 120 are generally "U" -shaped double cantilever beams, similar to the double beam cantilever sensor 12 shown in FIGURE 3.
  • any type of support medium may be used.
  • "U" -shaped beams 110 and 120 may be used so that electrical current directed into one leg 112a, 122a of the "U" will flow out of the other leg 112b, 122b, or the reverse .
  • Signal beam 110 and reference beam 120 include one or more piezoresistive regions (not explicitly shown in FIGURE 4) .
  • Signal beam 110 and reference beam 120 are preferably coupled to an electrical circuit 130 through the use of bonding pads 46, as shown in FIGURE 4.
  • Signal beam 110 is placed in a fluid flow to measure the magnitude and direction of the flow.
  • reference beam 120 is preferably not exposed to the fluid flow.
  • Electrical circuit 130 is used to measure the change in resistance of the piezoresistive material of beams 110 and 120. Through the use of electrical circuit 130, the output of signal beam 110 is referenced to the output of reference beam 120. Therefore, electrical circuit 130 includes the resistance of signal beam 110 while experiencing deflection by the fluid flow, and the resistance of reference beam 120, which is preferably undeflected.
  • the use of a signal/reference beam pair eliminates system drift due to changes in ambient conditions (such as temperature, humidity, vibration, etc.) in the monitoring environment .
  • electrical circuit 130 may include a Wheatstone bridge. The configuration of a Wheatstone bridge is well known in the art, so it will not be described in detail here. A Wheatstone bridge typically includes four main sources of resistance.
  • these sources of resistance are two resistors 132, signal beam 110, and reference beam 120.
  • Signal beam 110 is connected in one arm of the Wheatstone bridge, and reference beam 120 is connected in another arm of the bridge.
  • Electrical circuit 130 also preferably includes voltage source 134.
  • the change in resistance of the piezoresistive material of signal beam 110 is determined by measuring the output voltage of electrical circuit 130. Connecting reference beam 120 as one of the resistors eliminates common mode noise and interfering effects, and provides more accurate measurement of the change in resistance of the piezoresistive material of signal beam 110.
  • the output voltage is amplified using an amplifier 136.
  • the amplified voltage reading is then sent, via an interface 140, to a digital or analog output device. Examples of such devices are a digital signal processor 142, a central processing unit 144, and an analog output device 146.
  • the analog or digital output device may include a database that correlates a measured voltage or change in resistance with a certain magnitude and/or direction of the fluid flow. The analog or digital output device may then display or transmit the measured magnitude and/or direction to a user.
  • sensors incorporating the present invention allows them to manufactured in a variety of sizes. Such sensors may be manufactured in a size sufficient to measure flows in a normal environment, such as wind or river flows. Sensors incorporating the present invention may also be manufactured using a MEMS (micro- electromechanical systems) process. Sensors so manufactured may be used in microenvironments, such as in the fabrication of very large scale integrated circuits, or in the human body. MEMS sensors incorporating teachings of the present invention may be on the order of one hundred microns in size.
  • MEMS micro- electromechanical systems
  • sensors incorporating teachings of the present invention may be arrayed in groups. By arraying multiple sensors, the precise pattern of a fluid flow over a selected surface or in a selected area may be determined. Such a configuration will be explained using the cantilevered beam sensor design illustrated in FIGURES 1 and 2 as an example.
  • the magnitude of the resistance change of sensor 200 will indicate the magnitude of the fluid force component 210 that is perpendicular to surface 230 of sensor 200 contacting the fluid flow.
  • the fluid force component 220 parallel to surface 230 is generally not detected. Therefore, a single sensor 200 will generally only detect the full force of the fluid flow if surface 230 is perpendicular to the flow. For this reason, a single sensor will generally not be able to detect the direction of the fluid flow.
  • sensors 300a and 300b are oriented such that surfaces 330a and 330b are perpendicular to each other. Note, however, that surfaces 330a and 330b can be offset at any angle.
  • Sensor 330a is configured to measure the magnitude of the fluid force component 310 perpendicular to surface 330a.
  • sensor 330b is configured to measure the magnitude of the fluid force component 320 perpendicular to surface 330b.
  • the magnitude of fluid force components 310 and 320 may be combined to determine the magnitude and direction of the fluid flow.
  • While two sensors may be used to determine the precise magnitude and direction of a flow at a selected location, a multitude of such sensors may be arrayed to determine the precise magnitude and direction of a flow in several locations. Such an array may be useful when the fluid flow is not constant over a surface or in a selected area.
  • One example of an application of an arrayed configuration of sensors is "smart skin" technology on an airplane.
  • a plurality of sensors incorporating the present invention may be placed on various surfaces of an aircraft to precisely measure the air flow over the surfaces, and thus enable more accurate control of the aircraft .

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

Abstract

L'invention concerne un capteur permettant de détecter et de mesurer le débit et le sens d'un écoulement fluidique. Ce capteur comprend un matériau piézorésistif pouvant être exposé audit écoulement fluidique. Lorsque ce matériau piézorésistif est ainsi exposé, l'écoulement fluidique applique, de préférence, une force audit matériau piézorésistif. En réponse à cette force, la résistance du matériau piézorésistif peut changer. Le capteur comprend également un circuit électrique couplé au matériau piézorésistif. Le circuit électrique mesure, de préférence un changement quelconque de la résistance du matériau piézorésistif en réponse à son exposition à l'écoulement fluidique. Le changement de la résistance mesuré peut ensuite être corrélé avec un débit et/ou un sens de l'écoulement fluidique.
PCT/US1999/030661 1998-12-28 1999-12-21 Capteur d'ecoulement fluidique Ceased WO2000039537A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU22091/00A AU2209100A (en) 1998-12-28 1999-12-21 Fluid flow sensor

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US22139098A 1998-12-28 1998-12-28
US09/221,390 1998-12-28

Publications (1)

Publication Number Publication Date
WO2000039537A1 true WO2000039537A1 (fr) 2000-07-06

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PCT/US1999/030661 Ceased WO2000039537A1 (fr) 1998-12-28 1999-12-21 Capteur d'ecoulement fluidique

Country Status (2)

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AU (1) AU2209100A (fr)
WO (1) WO2000039537A1 (fr)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002041777A1 (fr) * 2000-11-21 2002-05-30 University Of Limerick Dispositif de conversion d'une caracteristique d'un ecoulement fluide en signal electronique, et controleur de flux respiratoire
WO2005049479A3 (fr) * 2003-11-18 2005-08-11 Univ Ruprecht Karls Heidelberg Surface pourvue d'une pluralite de saillies en forme de colonnes et utilisations de ladite surface
WO2007104978A1 (fr) * 2006-03-16 2007-09-20 The Science And Technology Facilities Council Sonde pour fluide
US8364427B2 (en) 2010-01-07 2013-01-29 General Electric Company Flow sensor assemblies
US8607619B2 (en) 2003-12-04 2013-12-17 Microvisk Limited Fluid probe
US8881578B2 (en) 2007-08-11 2014-11-11 Microvisk Ltd. Fluid probe
WO2014132138A3 (fr) * 2013-02-07 2014-12-18 King Abdullah University Of Science And Technology Procédé et capteurs conçus pour estimer et prédire l'écoulement de l'air autour des véhicules aériens
WO2017116499A1 (fr) * 2015-12-28 2017-07-06 The Trustees Of Princeton University Capteur de vitesse de filament élastique
CN108802421A (zh) * 2018-07-27 2018-11-13 北京航空航天大学 一种仿生流速传感器
CN113884701A (zh) * 2021-09-28 2022-01-04 东南大学 一种提高测量范围和全量程精度的风速风向传感器

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DE2244659A1 (de) * 1972-09-12 1974-03-21 Bosch Gmbh Robert Brennkraftmaschine mit einem luftmengenmesser fuer die ansaugluft
JPS60250259A (ja) * 1984-05-26 1985-12-10 Nippon Denso Co Ltd 流速検出装置
US4809552A (en) * 1987-11-23 1989-03-07 Allied-Signal, Inc. Multidirectional force-sensing transducer
EP0445508A2 (fr) * 1990-01-31 1991-09-11 SITEP S.p.A. Anémomètre
WO1997005824A1 (fr) * 1995-08-09 1997-02-20 Resmed Limited Appareil et procedes de controle de la respiration oro-nasale

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GB1252433A (fr) * 1968-01-31 1971-11-03
DE2244659A1 (de) * 1972-09-12 1974-03-21 Bosch Gmbh Robert Brennkraftmaschine mit einem luftmengenmesser fuer die ansaugluft
JPS60250259A (ja) * 1984-05-26 1985-12-10 Nippon Denso Co Ltd 流速検出装置
US4809552A (en) * 1987-11-23 1989-03-07 Allied-Signal, Inc. Multidirectional force-sensing transducer
EP0445508A2 (fr) * 1990-01-31 1991-09-11 SITEP S.p.A. Anémomètre
WO1997005824A1 (fr) * 1995-08-09 1997-02-20 Resmed Limited Appareil et procedes de controle de la respiration oro-nasale

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NISHIMOTO T ET AL: "BURIED PIEZORESISTIVE SENSORS BY MEANS OF MEV ION IMPLANTATION", SENSORS AND ACTUATORS A,CH,ELSEVIER SEQUOIA S.A., LAUSANNE, vol. A43, no. 1/03, 1 May 1994 (1994-05-01), pages 249 - 253, XP000454119, ISSN: 0924-4247 *
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Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002041777A1 (fr) * 2000-11-21 2002-05-30 University Of Limerick Dispositif de conversion d'une caracteristique d'un ecoulement fluide en signal electronique, et controleur de flux respiratoire
WO2005049479A3 (fr) * 2003-11-18 2005-08-11 Univ Ruprecht Karls Heidelberg Surface pourvue d'une pluralite de saillies en forme de colonnes et utilisations de ladite surface
US8607619B2 (en) 2003-12-04 2013-12-17 Microvisk Limited Fluid probe
WO2007104978A1 (fr) * 2006-03-16 2007-09-20 The Science And Technology Facilities Council Sonde pour fluide
JP2009530597A (ja) * 2006-03-16 2009-08-27 ザ サイエンス アンド テクノロジー ファシリティーズ カウンシル 流体プローブ
CN102323187A (zh) * 2006-03-16 2012-01-18 麦克罗威斯克有限公司 流体探针
US8297110B2 (en) 2006-03-16 2012-10-30 Microvisk Limited Fluid probe
US8881578B2 (en) 2007-08-11 2014-11-11 Microvisk Ltd. Fluid probe
US8874389B2 (en) 2010-01-07 2014-10-28 Amphenol Thermometrics, Inc. Flow sensor assemblies
US8364427B2 (en) 2010-01-07 2013-01-29 General Electric Company Flow sensor assemblies
WO2014132138A3 (fr) * 2013-02-07 2014-12-18 King Abdullah University Of Science And Technology Procédé et capteurs conçus pour estimer et prédire l'écoulement de l'air autour des véhicules aériens
US20150377915A1 (en) * 2013-02-07 2015-12-31 King Abdullah University Of Science And Technology Method and system for estimating and predicting airflow around air vehicles
WO2017116499A1 (fr) * 2015-12-28 2017-07-06 The Trustees Of Princeton University Capteur de vitesse de filament élastique
US10539443B2 (en) 2015-12-28 2020-01-21 The Trustees Of Princeton University Elastic filament velocity sensor
US11054290B2 (en) 2015-12-28 2021-07-06 The Trustees Of Princeton University Elastic filament velocity sensor
CN108802421A (zh) * 2018-07-27 2018-11-13 北京航空航天大学 一种仿生流速传感器
CN113884701A (zh) * 2021-09-28 2022-01-04 东南大学 一种提高测量范围和全量程精度的风速风向传感器

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