CN114200160A - Novel gas flow velocity and flow measurement system - Google Patents
Novel gas flow velocity and flow measurement system Download PDFInfo
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- CN114200160A CN114200160A CN202111439864.XA CN202111439864A CN114200160A CN 114200160 A CN114200160 A CN 114200160A CN 202111439864 A CN202111439864 A CN 202111439864A CN 114200160 A CN114200160 A CN 114200160A
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- 238000005259 measurement Methods 0.000 title claims abstract description 39
- 238000012545 processing Methods 0.000 claims abstract description 20
- 230000005865 ionizing radiation Effects 0.000 claims abstract description 17
- 229910001172 neodymium magnet Inorganic materials 0.000 claims description 13
- QJVKUMXDEUEQLH-UHFFFAOYSA-N [B].[Fe].[Nd] Chemical compound [B].[Fe].[Nd] QJVKUMXDEUEQLH-UHFFFAOYSA-N 0.000 claims description 9
- 238000004458 analytical method Methods 0.000 abstract description 3
- 230000005672 electromagnetic field Effects 0.000 abstract description 3
- 239000007789 gas Substances 0.000 description 64
- 230000005855 radiation Effects 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 150000002500 ions Chemical class 0.000 description 5
- 230000002285 radioactive effect Effects 0.000 description 4
- 238000000429 assembly Methods 0.000 description 3
- 230000000712 assembly Effects 0.000 description 3
- 230000008859 change Effects 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 230000002093 peripheral effect Effects 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 230000003321 amplification Effects 0.000 description 2
- 230000003750 conditioning effect Effects 0.000 description 2
- 230000005686 electrostatic field Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 238000003199 nucleic acid amplification method Methods 0.000 description 2
- 230000000149 penetrating effect Effects 0.000 description 2
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 description 1
- 230000005355 Hall effect Effects 0.000 description 1
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 229910052796 boron Inorganic materials 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 230000005284 excitation Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000004445 quantitative analysis Methods 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
Images
Classifications
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- 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
- G01P5/08—Measuring speed of fluids, e.g. of air stream; Measuring speed of bodies relative to fluids, e.g. of ship, of aircraft by measuring variation of an electric variable directly affected by the flow, e.g. by using dynamo-electric effect
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- 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
- G01F1/56—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 electric or magnetic effects
- G01F1/58—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 electric or magnetic effects by electromagnetic flowmeters
Abstract
The invention relates to a novel gas flow velocity and flow measurement system, belonging to a measurement system for measurement and analysis by using ionizing radiation and an electromagnetic field. The invention mainly comprises an ionizing radiation source, a magnetic field generating device and a signal acquisition and processing component. The invention can be widely applied to the measurement of the gas flow velocity and the gas flow in various industries.
Description
The technical field is as follows:
the invention belongs to the technical field of measurement and analysis by using ionizing radiation and electromagnetic fields, and particularly relates to a novel gas flow velocity and flow measurement system.
Background
The gas flow velocity and flow measurement is widely applied to various aspects of social production and life, and people often need to utilize the flow velocity and flow information of gas to complete important links such as automatic control, economic accounting, quantitative analysis and the like in relevant processes of industrial automatic production, energy industry metering links and scientific experiments. Therefore, accurate measurement of gas flow rate is crucial. The traditional gas flow velocity meter or gas flow meter is usually a contact type mechanical structure, for example, the flow velocity information of gas is obtained by collecting the rotating speed signal of a rotor of the flow velocity meter and processing and calculating, and the contact type structure has a certain blocking effect on the flowing gas, and the flow velocity of the gas can be influenced to a certain extent, so that the measurement precision is reduced. Under the background, a novel non-contact gas flow velocity and flow measurement system can be realized by utilizing an electromagnetic field and an ionizing effect of an ionizing radiation source.
Disclosure of Invention
The invention aims to provide a novel gas flow velocity and flow measurement system which is established by combining an ionization radiation source, a magnetic field generating device and a signal analysis system and overcomes the defects of the existing contact type gas flow velocity and flow meter.
The purpose of the invention is realized by the following technical scheme:
a novel gas flow velocity and flow measurement system comprises an ionizing radiation source, a collimation shielding module of the ionizing radiation source, a measurement module and a signal acquisition and processing assembly;
the ionizing radiation source and the collimation shielding module thereof comprise a shielding body, a shielding upper cover and a collimation hole, wherein the shielding body is a device with a cavity, parallel fixing components are arranged on the upper end surface and the lower end surface of the shielding body, the shielding upper cover is arranged at the top end of the shielding body, and the collimation hole is arranged on the side surface of the shielding body;
the measuring module comprises a magnetic field generating device and a gas guide pipe with electrodes, two supporting frames are arranged on the gas guide pipe, supporting columns are arranged on the supporting frames and connected with the parallel fixing component, the gas guide pipe is fixed in the middle of the parallel fixing component in parallel and is kept horizontal, the magnetic field generating device comprises neodymium iron boron magnets, and the two neodymium iron boron magnets are respectively positioned above and below the gas guide pipe and connected with the parallel fixing component through the supporting columns;
the signal acquisition and processing assembly comprises a signal acquisition and processing assembly, and the signal acquisition and processing assembly is arranged on the parallel fixing assembly above the signal acquisition and processing assembly.
Furthermore, the gas guide pipe is parallel to the upper and lower neodymium iron boron magnets at equal intervals.
Further, the gas collimating holes are opposite to the gas guide pipe.
Furthermore, the electrode is arranged in the center of the inner side wall of the gas guide pipe and is perpendicular to the positions of the upper neodymium iron boron magnet and the lower neodymium iron boron magnet, and the two sides of the electrode are symmetrical.
The invention has the beneficial effects that:
the utility model provides a novel gas velocity of flow measurement system can the wide application in the measurement of each trade gas velocity of flow, overcomes current contact gas velocity of flow flowmeter's not enough. The system has low power demand, and can measure the gas flow velocity and flow in an outdoor environment which is not easy to be wired or cannot be supplied with power. The invention can change the size of the magnetic field so as to change the size of the Hall voltage, thereby meeting different measuring ranges.
Drawings
FIG. 1: a flow velocity and flow measurement schematic diagram of a novel gas flow velocity and flow measurement system;
FIG. 2: a gas flow velocity and flow measurement system schematic diagram of a novel gas flow velocity and flow measurement system;
FIG. 3: a cross-sectional view of a shielding collimation module of a novel gas flow velocity and flow measurement system (a radioactive source is used as an ionizing radiation source);
FIG. 4: a shielding collimation module schematic diagram (adopting an X-ray tube as an ionization radiation source) of a novel gas flow velocity and flow measurement system;
FIG. 5: a measuring electrode schematic diagram of a novel gas flow velocity and flow measurement system;
FIG. 6: a signal acquisition and processing component system block diagram of a novel gas flow velocity and flow measurement system.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
A novel gas flow velocity and flow measurement system comprises an ionizing radiation source, a collimation shielding module of the ionizing radiation source, a measurement module and a signal acquisition and processing assembly. The components and functions are realized as follows:
the ionization radiation source and the collimation shielding module thereof are integrally a device with a cavity, the forming materials can be lead, stainless steel and other shielding materials, the internal part is hollow, the ionization radiation source placing structure and the collimation hole 4 in the horizontal direction are included, and different structures can be manufactured in the internal space according to the shape and the size of the specific ionization radiation source in consideration of the selection of different ionization radiation sources;
the measuring module consists of a magnetic field generating device and a gas guide pipe 8 with an electrode 15, the magnetic field generating device generates a magnetic field penetrating through the gas guide pipe 8 in the vertical direction so as to cause Hall voltage, and an external fixing component can enable collimated ionizing radiation to irradiate one side of the gas guide pipe 8 in the horizontal direction;
the signal acquisition and processing assembly comprises a reading module, a signal conditioning and analyzing module and a peripheral. The reading module amplifies and shapes the Hall voltage led out by the measuring module, the signal conditioning and analyzing module further filters, extracts and converts the signal to obtain gas flow velocity information, and finally information display is carried out by peripheral equipment, wherein the peripheral equipment can comprise keys, a display screen, an alarm, various interfaces and the like, and can also be directly connected with an industrial personal computer and a computer.
Example 1:
a novel gas flow velocity and flow measurement system is shown in the overall structure of figure 2. Shield 2, shield cover 3, collimation holes 4 in fig. 2 and inner chamber 11, cylindrical in fig. 360The Co radioactive source 12 constitutes an ionizing radiation source and its collimating shielding module. The shielding upper cover 3 is placed at the top end of the shielding body 2 for preventing radiation in the inner chamber 11 from leaking out, as shown in fig. 2, and the shielding upper cover 3 can be opened and a radioactive source can be placed in a limiting groove at the bottom of the inner chamber 11 in operation, as shown in fig. 3. The gas draft tube 8, the flange assembly 9, the ru fe boron magnet 7 in fig. 2 and the electrode 15 in fig. 5 constitute a measurement module. The gas honeycomb duct 8 is fixed in the middle of the upper and lower parallel fixed assemblies 1 through the supporting frame 10 and the supporting column 6 and is kept horizontal, the flange assemblies 9 on the two sides of the honeycomb duct can be used for connecting a pipeline to be tested, and the two neodymium iron boron magnets 7 are also fixed on the upper and lower parallel fixed assemblies 1 through the supporting column, so that the gas honeycomb duct 8 is equidistantly parallel to the upper and lower neodymium iron boron magnets, as shown in fig. 2. In addition, the parallel fixing component 1 also connects the ionizing radiation source and the collimation shielding module thereof with the measuring module, so that the collimation hole 4 is opposite to the gas guide pipe 8. Signal acquisition and processing in FIG. 2The component 5 is arranged above the parallel fixed component 1, the controller integrates a signal acquisition and processing component and can be connected with an electrode 15 inside the gas guide pipe 8 through a signal wire, the electrode 15 is arranged in the center of the inner side wall of the guide pipe and is vertical to the upper magnet and the lower magnet, and the two sides of the electrode are symmetrical, as shown in figure 5. A block diagram of an internal system of the signal acquisition and processing assembly is shown in fig. 6.
In this case placed in a chamber inside the shield60Gamma rays generated by the Co radioactive source 12 are irradiated to the side surface of the gas guide pipe 8 through the collimation hole 4, so that internal gas molecules are ionized to generate ions. The two neodymium iron boron magnets 7 are used as a magnetic field generating device to generate a magnetic field penetrating through gas in the flow guide pipe, ions and electrons generated by gas ionization generate a Hall effect and generate a transverse Hall voltage, and the magnitude of the voltage is in positive correlation with the flow rate of the gas. The Hall voltage enters the signal acquisition and processing assembly in the signal acquisition and processing assembly 5, then the signal is subjected to impedance conversion and preliminary amplification by the preamplifier, then the signal is subjected to shaping amplification by the main amplifying circuit and then is digitized by the ADC, the digitized signal is filtered and extracted by the FPGA, and the result is processed by the singlechip. Conversion coefficients of different gas flow velocities and Hall voltage signals in the pipeline can be obtained through coefficient calibration, so that the flow velocity information of the gas can be obtained through conversion calculation by the single chip microcomputer, and further the flow information of the gas can be obtained through the cross-sectional area of the pipeline. The design adopts a rechargeable lithium battery to supply power for the signal acquisition and processing component 5, and the controller is provided with a display screen and keys, so that measurement data can be displayed at any time and the calibration coefficient can be set. The arrangement has low power requirement, and the system can be used for measuring the gas flow velocity and the gas flow in an outdoor environment which is not easy to wire or cannot supply power.
Example 2:
a novel gas flow rate and flow measurement system, substantially the same as described in example 1, except that the ionizing radiation source used is an X-ray tube 13 which can be directly inserted into the shield 2 of the device and which maintains the X-ray window 14 in alignment with the collimation aperture 4, as shown in figure 4. The X-rays are emitted by the X-ray window 14 and collimated through the collimating aperture 4 to the side of the gas guiding tube 8. By adjusting the X-ray tube to output different energies, X-rays of different intensities can be adapted to different measurement gases.
Example 3:
the structure of the novel gas flow velocity and flow measurement system is basically the same as that described in example 1, and the difference is that a magnetic field generating device for providing a magnetic field is an electromagnet, and the size of the magnetic field can be changed by adjusting excitation voltage so as to change the size of Hall voltage and meet different measurement ranges.
The invention is realized according to the following measurement principle:
as shown in fig. 1, two magnets add a magnetic induction intensity of
The magnetic field of (1). When the gaseous medium is at a velocity
When the gas flows through the gas guide pipe with the cross section width of b and the height of h, because gas atoms are ionized under the irradiation of ionizing radiation, electrons and positive ions are respectively subjected to the action of Lorentz force, and the force is as follows:
in the formula
Is the velocity of movement of electrons or positive ions, i.e. the flow rate of the gaseous medium. Under the action of Lorentz force, electrons and positive ions move to two sides of the guide pipe respectively, and charge accumulation is formed on two sides of the guide pipe, so that additional electrostatic fields are formed on two sides of the guide pipe
According to the equilibrium condition of the electron receiving electric field force and the Lorentz force:
can obtain electrostatic field in balanced state
Size E ofhFrom vB, the hall potential difference generated across the conduit in equilibrium is:
in the formula, Q is the flow of the gas medium, and the magnitude of the Hall potential difference is directly proportional to the flow velocity and the flow of the gas medium. Therefore, by measuring the magnitude of the Hall potential difference and completing coefficient calibration, the flow speed and the flow of the corresponding gas flowing through the pipeline can be accurately measured.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (4)
1. A novel gas flow velocity and flow measurement system is characterized in that: comprises an ionizing radiation source, a collimation shielding module, a measuring module and a signal acquisition and processing component;
the ionizing radiation source and the collimation shielding module thereof comprise a shielding body (2), a shielding upper cover (3) and a collimation hole (4), wherein the shielding body (2) is a device with a cavity, the upper end face and the lower end face of the shielding body (2) are both provided with parallel fixing components (1), the shielding upper cover (3) is placed at the top end of the shielding body (2), and the collimation hole (4) is arranged on the side face of the shielding body (2);
the measuring module comprises a magnetic field generating device, a gas guide pipe (8) with an electrode (15), two supporting frames (10) are installed on the gas guide pipe (8), supporting columns (6) are installed on the supporting frames (10), the supporting columns (6) are connected with the parallel fixed assembly (1), the gas guide pipe (8) is parallelly fixed in the middle of the parallel fixed assembly (1) and kept horizontal, the magnetic field generating device comprises neodymium-iron-boron magnets (7), and the two neodymium-iron-boron magnets (7) are respectively located above and below the gas guide pipe (8) and are connected with the parallel fixed assembly (1) through the supporting columns (6);
the signal acquisition and processing assembly comprises a signal acquisition and processing assembly (5), and the signal acquisition and processing assembly (5) is arranged on the upper parallel fixing assembly (1).
2. A novel gas flow rate and flow measurement system, according to claim 1, wherein: the gas guide pipe (8) is parallel to the upper and lower neodymium iron boron magnets (7) at equal intervals.
3. A novel gas flow rate and flow measurement system, according to claim 1, wherein: the collimation hole (4) is over against the gas guide pipe (8).
4. A novel gas flow rate and flow measurement system, according to claim 1, wherein: the electrode (15) is arranged in the center of the inner side wall of the gas guide pipe (8) and is vertical to the positions of the upper neodymium iron boron magnet (7) and the lower neodymium iron boron magnet (7), and the two sides of the electrode are symmetrical.
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| CN202111439864.XA CN114200160A (en) | 2021-11-30 | 2021-11-30 | Novel gas flow velocity and flow measurement system |
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| CN202111439864.XA CN114200160A (en) | 2021-11-30 | 2021-11-30 | Novel gas flow velocity and flow measurement system |
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1087715A (en) * | 1992-12-03 | 1994-06-08 | 曲义坤 | Radioactive ionization capacitor and electromagnetic gas flowmeter |
| DE202004012853U1 (en) * | 2004-08-17 | 2005-02-24 | Fürst, Peter, Dr. | Sensors for measuring the flow speed and mass flow of liquids, pastes, suspensions and muds comprises probes attached to mounting devices that are deflected by the flow causes a change in an electrical measurement signal |
| CN205373786U (en) * | 2016-01-19 | 2016-07-06 | 崔婧轩 | Blowdown monitoring devices |
| CN108444554A (en) * | 2018-02-28 | 2018-08-24 | 重庆川仪自动化股份有限公司 | The method and flowmeter of biphase gas and liquid flow are measured using electromagnetism vortex street principle |
| CN209927191U (en) * | 2019-05-01 | 2020-01-10 | 浙江环茂自控科技有限公司 | Electromagnetic flowmeter for flow detection in controller |
| DE102018126679A1 (en) * | 2018-10-25 | 2020-04-30 | Endress + Hauser Flowtec Ag | Magnetic-inductive flow meter and a method for operating a magnetic-inductive flow meter |
| CN211878013U (en) * | 2020-05-21 | 2020-11-06 | 沈阳航空航天大学 | Fluid flow rate measuring device |
| CN112229457A (en) * | 2020-11-19 | 2021-01-15 | 吉林大学 | Novel electromagnetic flowmeter and measuring method thereof |
| CN112665821A (en) * | 2020-12-21 | 2021-04-16 | 西安交通大学 | Device and method for measuring speed and vorticity in conductive fluid under strong magnetic field condition |
-
2021
- 2021-11-30 CN CN202111439864.XA patent/CN114200160A/en active Pending
Patent Citations (9)
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|---|---|---|---|---|
| CN1087715A (en) * | 1992-12-03 | 1994-06-08 | 曲义坤 | Radioactive ionization capacitor and electromagnetic gas flowmeter |
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| DE102018126679A1 (en) * | 2018-10-25 | 2020-04-30 | Endress + Hauser Flowtec Ag | Magnetic-inductive flow meter and a method for operating a magnetic-inductive flow meter |
| CN209927191U (en) * | 2019-05-01 | 2020-01-10 | 浙江环茂自控科技有限公司 | Electromagnetic flowmeter for flow detection in controller |
| CN211878013U (en) * | 2020-05-21 | 2020-11-06 | 沈阳航空航天大学 | Fluid flow rate measuring device |
| CN112229457A (en) * | 2020-11-19 | 2021-01-15 | 吉林大学 | Novel electromagnetic flowmeter and measuring method thereof |
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