WO2021125946A1 - Measuring device for measuring an air flow - Google Patents

Measuring device for measuring an air flow Download PDF

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Publication number
WO2021125946A1
WO2021125946A1 PCT/NL2020/050790 NL2020050790W WO2021125946A1 WO 2021125946 A1 WO2021125946 A1 WO 2021125946A1 NL 2020050790 W NL2020050790 W NL 2020050790W WO 2021125946 A1 WO2021125946 A1 WO 2021125946A1
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WO
WIPO (PCT)
Prior art keywords
air flow
air
shaped
opening
flow sensor
Prior art date
Application number
PCT/NL2020/050790
Other languages
French (fr)
Inventor
dr. ir. Niek-Jan BINK
Original Assignee
Acin Instrumenten B.V.
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 Acin Instrumenten B.V. filed Critical Acin Instrumenten B.V.
Publication of WO2021125946A1 publication Critical patent/WO2021125946A1/en

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Classifications

    • 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
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15D—FLUID DYNAMICS, i.e. METHODS OR MEANS FOR INFLUENCING THE FLOW OF GASES OR LIQUIDS
    • F15D1/00—Influencing flow of fluids
    • F15D1/001—Flow of fluid from conduits such as pipes, sleeves, tubes, with equal distribution of fluid flow over the evacuation surface
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15D—FLUID DYNAMICS, i.e. METHODS OR MEANS FOR INFLUENCING THE FLOW OF GASES OR LIQUIDS
    • F15D1/00—Influencing flow of fluids
    • F15D1/02—Influencing flow of fluids in pipes or conduits
    • F15D1/025—Influencing flow of fluids in pipes or conduits by means of orifice or throttle elements
    • 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
    • G01P5/02—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring forces exerted by the fluid on solid bodies, e.g. anemometer
    • G01P5/06—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring forces exerted by the fluid on solid bodies, e.g. anemometer using rotation of vanes
    • 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
    • G01P5/10—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring thermal variables
    • G01P5/12—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring thermal variables using variation of resistance of a heated conductor
    • 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

Definitions

  • the invention relates to a device which is intended and arranged as (a part of) a measuring device for measuring an air flow that is introduced into, or withdrawn from, a space by means of a ventilating outlet or air outlet passage or grating.
  • a measuring device is often referred to as an air flow meter.
  • the air flow meter of the present type is generally used for inspection, maintenance and adjustment of room ventilating systems.
  • the object of the present invention is to provide an air flow meter of the above- mentioned type which is simple and yet provides very reliable measurement results.
  • a device which is intended and arranged as a measuring device for measuring an air flow that is introduced into, or withdrawn from, a space by means of a ventilating outlet or air outlet passage or grating, hereinafter all together in brief referred to as a vent opening;
  • the device comprises an essentially funnel-shaped housing having a large inlet opening and, preferably by means of an interposed streamlined side wall, comprises a smaller outlet opening, wherein the size of the inlet opening is chosen such that it can enclose/encircle the vent opening;
  • the device further comprises an air diffusor body arranged to guide or direct during use the air introduced into, or withdrawn from, the vent opening through the inlet opening of the funnel-shaped housing, and which body is mounted by means of a frame within the funnel-shaped housing, wherein the air diffusor body is provided with the form of an aerodynamically shaped body(surface) of revolution, for example generally droplet-shaped or wing-shaped (i.e.
  • the body of revolution having a relatively broad front side facing the inlet opening of the funnel-shaped housing, and having a relatively narrow rear side facing the outlet opening thereof; wherein the housing near its outlet opening can be coupled or is coupled to an air flow sensor.
  • air flow sensor can also be understood to include a flow meter, an anemometer and/or mass flow meter, or the relevant sensor part thereof, for example a vane sensor or turbine blade sensor, a hot wire sensor, ultrasonic sensor, a differential pressure sensor, for example Pitot-sensor, or a laser Doppler sensor.
  • the broad front side i.e.
  • the front side of the wide portion) of the body of revolution is essentially torpedo-shaped, preferably having a pointed nose.
  • This preferred shape has been found to provide excellent results in practice, because the air flow (to be measured), which is introduced (delivered) or withdrawn through the vent openings, is homogenized by the air diffusor body, whereby the occurrence of turbulence is minimized. Subsequently, the air flow is provided to the air flow sensor, which converts the measured air flow rate (in air mass or air volume per unit of time) into an (analog or digital) signal value.
  • the air flow sensor comprises, for example, an air turbine wheel (rotor) which is arranged in line with the narrow rear side of the diffusor body near or within the outlet opening of the housing.
  • the air turbine wheel is connected to a small generator that converts the speed of the air turbine wheel into electrical energy, of which the voltage or frequency can be measured and converted by means of some electronics into an air flow rate, which can then be displayed on a display.
  • Figure 1 shows an exemplary embodiment of the device according to the invention.
  • Figure 1 shows an exemplary embodiment of the device 1 according to the invention, intended and arranged as a measuring device for measuring an air flow that is introduced into, or withdrawn from, a space by means of a ventilating outlet or air outlet passage or grating, hereinafter referred to as vent opening.
  • a ventilating outlet or air outlet passage or grating hereinafter referred to as vent opening.
  • the device 1 comprises an essentially funnel-shaped housing 2 with a large inlet opening 2a and, by means of an intermediate/interposed streamlined side wall 2b, a smaller outlet opening 2c, wherein the size of the inlet opening 2a is chosen such, that it can enclose/encircle the vent opening (not shown).
  • the device comprises an air diffusor body 3, which is arranged to guide or direct during use the air introduced or withdrawn through the vent opening through the inlet opening 2a of the funnel-shaped housing 2, the diffusor body being mounted by means of a frame 4 within the funnel-shaped housing 2.
  • the air diffusor body 3 is provided with the form of an aerodynamically shaped, for example essentially droplet-shaped or wing-shaped, body/surface of revolution having a relatively broad front side 3a facing the side of the inlet opening 2a of the funnel- shaped housing 2, and having a relatively narrow rear side 3b facing towards the outlet opening 2c thereof.
  • the housing 2 can be coupled or is (fixedly) coupled (for instance "clickable") to an air flow sensor 5.
  • the broad front side 3a of the essentially droplet-shaped body of revolution 3 is torpedo-shaped with a pointed nose 3c.
  • the air flow sensor 5 comprises an air turbine wheel (rotor) 5a, which is arranged near or within the outlet opening 2c of the housing 2, in line with the narrow rear side 3b of the diffusor body 3.
  • an outflow member 6, which is flared outwardly, smoothly or in a streamlined manner, is further arranged in line with the outlet opening 2c of the housing 2, which member is coupled (for example “clickable") or (fixedly) coupled to the air flow sensor 5 and/or to the outlet opening 2c. Due to the flared design of the outflow member 6, turbulence of the outflowing air - which could undesirably influence the measurement result - is reduced to a minimum.
  • an operating handle 7 is provided, which is also able to contain a display (not shown).
  • the air turbine wheel 5a is connected to a small generator (not explicitly shown) which converts the speed of the air turbine wheel 5a into electrical energy, the voltage or frequency of which can be measured and, by means of some electronics, can be displayed as a measured value of the detected air flow rate on a display, for example integrated in the handle 7.
  • an air flow meter which comprises an air turbine wheel (rotor) (5a) as a sensor
  • use can also be made of other types of air flow meters air flow meters, anemometers, mass flow meters, etc.
  • air flow meters air flow meters, anemometers, mass flow meters, etc.
  • a hot wire or thermal anemometer or at least the sensor part thereof may also be used, or a pressure difference anemometer, for instance comprising a Pitot-tube or matrix, or at least the sensor part thereof, or an ultrasonic anemometer or at least the sensor part thereof, or a laser Doppler anemometer or at least the sensor part thereof (see also https://en.wikipedia.org/wiki/Anemometer https://en.wikipedia.org/wiki/Flow_measurement https://www.flowcenter.nI/en/training-and-education/education/flow-measurement/J
  • the present invention provides for an air flow meter for performing measurements on room ventilating systems, which flow meter is simple yet provides very reliable measurement results.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • General Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Measuring Volume Flow (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)

Abstract

Device (1) for measuring an air flow that is introduced into, or withdrawn from, a space through a ventilating opening. The device comprises a housing (2) having a large inlet opening (2a) and a smaller outlet opening (2c). The device comprises an air diffusor body (3) which is in the form of a droplet-shaped or wing-shaped body of revolution, preferably, with a torpedo-shaped front side (3a) facing towards the inlet opening of the funnel-shaped housing, and with a relatively narrow rear side (3b), facing towards the outlet opening. The housing near its outlet opening is connected to an air flow sensor (5), for example provided with an air rotor (5a). Furthermore, a outflow member (6) is provided, flaring outwardly.

Description

Title: Measuring device for measuring an air flow
DESCRIPTION
The invention relates to a device which is intended and arranged as (a part of) a measuring device for measuring an air flow that is introduced into, or withdrawn from, a space by means of a ventilating outlet or air outlet passage or grating. Such a measuring device is often referred to as an air flow meter. The air flow meter of the present type is generally used for inspection, maintenance and adjustment of room ventilating systems.
The object of the present invention is to provide an air flow meter of the above- mentioned type which is simple and yet provides very reliable measurement results.
To this end, according to the invention, a device is provided which is intended and arranged as a measuring device for measuring an air flow that is introduced into, or withdrawn from, a space by means of a ventilating outlet or air outlet passage or grating, hereinafter all together in brief referred to as a vent opening; wherein the device comprises an essentially funnel-shaped housing having a large inlet opening and, preferably by means of an interposed streamlined side wall, comprises a smaller outlet opening, wherein the size of the inlet opening is chosen such that it can enclose/encircle the vent opening; wherein the device further comprises an air diffusor body arranged to guide or direct during use the air introduced into, or withdrawn from, the vent opening through the inlet opening of the funnel-shaped housing, and which body is mounted by means of a frame within the funnel-shaped housing, wherein the air diffusor body is provided with the form of an aerodynamically shaped body(surface) of revolution, for example generally droplet-shaped or wing-shaped (i.e. corresponding to the cross-section of a wing), the body of revolution having a relatively broad front side facing the inlet opening of the funnel-shaped housing, and having a relatively narrow rear side facing the outlet opening thereof; wherein the housing near its outlet opening can be coupled or is coupled to an air flow sensor. In the context of the present invention, the term air flow sensor can also be understood to include a flow meter, an anemometer and/or mass flow meter, or the relevant sensor part thereof, for example a vane sensor or turbine blade sensor, a hot wire sensor, ultrasonic sensor, a differential pressure sensor, for example Pitot-sensor, or a laser Doppler sensor. Preferably, the broad front side (i.e. the front side of the wide portion) of the body of revolution is essentially torpedo-shaped, preferably having a pointed nose. This preferred shape has been found to provide excellent results in practice, because the air flow (to be measured), which is introduced (delivered) or withdrawn through the vent openings, is homogenized by the air diffusor body, whereby the occurrence of turbulence is minimized. Subsequently, the air flow is provided to the air flow sensor, which converts the measured air flow rate (in air mass or air volume per unit of time) into an (analog or digital) signal value.
The air flow sensor comprises, for example, an air turbine wheel (rotor) which is arranged in line with the narrow rear side of the diffusor body near or within the outlet opening of the housing. For example, the air turbine wheel is connected to a small generator that converts the speed of the air turbine wheel into electrical energy, of which the voltage or frequency can be measured and converted by means of some electronics into an air flow rate, which can then be displayed on a display.
The invention will now be discussed in more detail with reference to the figure description below.
Figure 1 shows an exemplary embodiment of the device according to the invention.
Figure 1 shows an exemplary embodiment of the device 1 according to the invention, intended and arranged as a measuring device for measuring an air flow that is introduced into, or withdrawn from, a space by means of a ventilating outlet or air outlet passage or grating, hereinafter referred to as vent opening.
The device 1 comprises an essentially funnel-shaped housing 2 with a large inlet opening 2a and, by means of an intermediate/interposed streamlined side wall 2b, a smaller outlet opening 2c, wherein the size of the inlet opening 2a is chosen such, that it can enclose/encircle the vent opening (not shown).
Furthermore, the device comprises an air diffusor body 3, which is arranged to guide or direct during use the air introduced or withdrawn through the vent opening through the inlet opening 2a of the funnel-shaped housing 2, the diffusor body being mounted by means of a frame 4 within the funnel-shaped housing 2. The air diffusor body 3 is provided with the form of an aerodynamically shaped, for example essentially droplet-shaped or wing-shaped, body/surface of revolution having a relatively broad front side 3a facing the side of the inlet opening 2a of the funnel- shaped housing 2, and having a relatively narrow rear side 3b facing towards the outlet opening 2c thereof.
Near its outlet opening 2c, the housing 2 can be coupled or is (fixedly) coupled (for instance "clickable") to an air flow sensor 5.
In the embodiment shown, the broad front side 3a of the essentially droplet-shaped body of revolution 3 is torpedo-shaped with a pointed nose 3c.
In the embodiment shown, the air flow sensor 5 comprises an air turbine wheel (rotor) 5a, which is arranged near or within the outlet opening 2c of the housing 2, in line with the narrow rear side 3b of the diffusor body 3.
In the embodiment shown, an outflow member 6, which is flared outwardly, smoothly or in a streamlined manner, is further arranged in line with the outlet opening 2c of the housing 2, which member is coupled (for example "clickable") or (fixedly) coupled to the air flow sensor 5 and/or to the outlet opening 2c. Due to the flared design of the outflow member 6, turbulence of the outflowing air - which could undesirably influence the measurement result - is reduced to a minimum.
Finally, an operating handle 7 is provided, which is also able to contain a display (not shown). For example, the air turbine wheel 5a is connected to a small generator (not explicitly shown) which converts the speed of the air turbine wheel 5a into electrical energy, the voltage or frequency of which can be measured and, by means of some electronics, can be displayed as a measured value of the detected air flow rate on a display, for example integrated in the handle 7.
Instead of an air flow meter, which comprises an air turbine wheel (rotor) (5a) as a sensor, use can also be made of other types of air flow meters (air flow meters, anemometers, mass flow meters, etc.). For example, as an (alternative) air flow sensor, a hot wire or thermal anemometer or at least the sensor part thereof may also be used, or a pressure difference anemometer, for instance comprising a Pitot-tube or matrix, or at least the sensor part thereof, or an ultrasonic anemometer or at least the sensor part thereof, or a laser Doppler anemometer or at least the sensor part thereof (see also https://en.wikipedia.org/wiki/Anemometer https://en.wikipedia.org/wiki/Flow_measurement https://www.flowcenter.nI/en/training-and-education/education/flow-measurement/J Hence, the present invention provides for an air flow meter for performing measurements on room ventilating systems, which flow meter is simple yet provides very reliable measurement results.

Claims

1. Device (1) intended and arranged as a measuring device for measuring an air flow that is introduced into, or withdrawn from, a space by means of a ventilating outlet or air outlet passage or grating, hereinafter referred to as vent opening; wherein the device comprises an essentially funnel-shaped housing (2) having a large inlet opening (2a) and, preferably comprises a streamlined side wall (2b) and, comprises a smaller outlet opening (2c), the size of the inlet opening being chosen such that it encloses the vent opening; wherein the device further comprises an air diffusor body (3) arranged to guide or direct the air introduced into, or withdrawn from, the vent opening, wherein the body is mounted within the funnel-shaped housing, wherein the air diffusor body is provided with the form of an aerodynamically shaped body(surface) of revolution, for example generally droplet-shaped or wing shaped, the body of revolution having a relatively broad front side (3a) facing the inlet opening of the funnel-shaped housing, and having a relatively narrow rear side (3b) facing the outlet opening thereof; wherein the housing near its outlet opening can be coupled or is coupled to an air flow sensor (5).
2. Device according to claim 1, wherein the broad front side of the body of revolution is essentially torpedo-shaped, preferably having a pointed nose (3c).
3. Device according to claim 1 or 2, comprising a smoothly or streamlined outwardly flared outflow member (6), which can be coupled or is coupled to the air flow sensor and/or to the outlet opening.
4. Device according to any one of the claims 1 - 3, wherein the air flow sensor comprises an air turbine wheel (5a).
5. Device according to any one of the claims 1 - 3, wherein the air flow sensor comprises a hot-wire-anemometer or at least the sensor portion thereof.
6. Device according to any one of the claims 1 - 3, wherein the air flow sensor comprises a pressure difference anemometer, comprising for instance a Pitot-tube, or -matrix, or at least includes the sensor portion thereof.
7. Device according to any one of the claims 1 - 3, wherein the air flow sensor is an ultrasonic anemometer, or at least the sensor portion thereof.
PCT/NL2020/050790 2019-12-19 2020-12-15 Measuring device for measuring an air flow WO2021125946A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NL1043512 2019-12-19
NL1043512A NL1043512B1 (en) 2019-12-19 2019-12-19 Air flow meter for measurement on room ventilation systems, comprising an air distribution body

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WO2021125946A1 true WO2021125946A1 (en) 2021-06-24

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115420863A (en) * 2022-11-04 2022-12-02 四川瑞吉绿能科技有限公司 Method for improving measurement accuracy of gas carbon content
CN115902288A (en) * 2022-11-11 2023-04-04 无锡德润电子有限公司 Wind speed induction controller

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE7539850U (en) * 1975-12-13 1976-04-08 Brown, Boveri & Cie Ag, 6800 Mannheim FLOW METER
US5487311A (en) * 1995-04-04 1996-01-30 The United States Of America As Represented By The Secretary Of The Army Air velocity averaging rotor
DE19529544A1 (en) * 1995-08-11 1997-02-13 Kessler & Luch Gmbh Pressure or volume flow measurement arrangement - includes enclosed measuring tube inserted in inlet direction of flow, whose end is open towards outlet direction, and which is connected with pressure sensor for determining interior pressure in tube
CN201060209Y (en) * 2007-06-15 2008-05-14 王沛云 Novel portable propeller current velocity sensor

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE7539850U (en) * 1975-12-13 1976-04-08 Brown, Boveri & Cie Ag, 6800 Mannheim FLOW METER
US5487311A (en) * 1995-04-04 1996-01-30 The United States Of America As Represented By The Secretary Of The Army Air velocity averaging rotor
DE19529544A1 (en) * 1995-08-11 1997-02-13 Kessler & Luch Gmbh Pressure or volume flow measurement arrangement - includes enclosed measuring tube inserted in inlet direction of flow, whose end is open towards outlet direction, and which is connected with pressure sensor for determining interior pressure in tube
CN201060209Y (en) * 2007-06-15 2008-05-14 王沛云 Novel portable propeller current velocity sensor

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115420863A (en) * 2022-11-04 2022-12-02 四川瑞吉绿能科技有限公司 Method for improving measurement accuracy of gas carbon content
CN115902288A (en) * 2022-11-11 2023-04-04 无锡德润电子有限公司 Wind speed induction controller
CN115902288B (en) * 2022-11-11 2023-09-05 无锡德润电子有限公司 Wind speed induction controller

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