CN117517706A - Processing method for obtaining flow velocity signal by using ultrasonic reflection type flow velocity measuring instrument - Google Patents
Processing method for obtaining flow velocity signal by using ultrasonic reflection type flow velocity measuring instrument Download PDFInfo
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- CN117517706A CN117517706A CN202311486081.6A CN202311486081A CN117517706A CN 117517706 A CN117517706 A CN 117517706A CN 202311486081 A CN202311486081 A CN 202311486081A CN 117517706 A CN117517706 A CN 117517706A
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- 238000005259 measurement Methods 0.000 claims abstract description 17
- 230000005540 biological transmission Effects 0.000 claims description 16
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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
- G01P5/24—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
- G01P5/241—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 using reflection of acoustical waves, i.e. Doppler-effect
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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
- G01P5/24—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
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Abstract
The invention discloses a processing method for obtaining a flow velocity signal by using an ultrasonic reflection type flow velocity measuring instrument, wherein: the measuring instrument comprises an ultrasonic transducer I, an ultrasonic transducer II, a transducer collimation coupling component and a probe rod; the probe rod is a circular pipe fitting with a hollow inside; the front ends of the ultrasonic transducer I and the ultrasonic transducer II are respectively provided with a transducer collimation coupling component; the ultrasonic transducer I and the ultrasonic transducer II are fixedly arranged at one end of the probe rod; the other end of the probe rod is a reflecting end, and an opening is arranged on the probe rod close to the reflecting end and is used as a measuring area. The device has simple structure and low manufacturing cost, when in use, the reflecting end and the measuring area are only required to be placed in the flue at a certain inclination angle, the ultrasonic transducer is completely placed outside the flue, the special design of high-temperature resistant materials is not required, the design cost of the transducer is greatly reduced, and the influence of the high-temperature environment on the accuracy of ultrasonic measurement is avoided.
Description
Technical Field
The invention belongs to the technical field of ultrasonic technology and acoustic detection, and particularly relates to a processing method for obtaining a flow velocity signal by using an ultrasonic reflection type flow velocity measuring instrument.
Background
The ultrasonic flow measurement technique is a technique for estimating the flow rate of a fluid by measuring the propagation velocity of ultrasonic waves in the fluid. Currently, ultrasonic flow measurement techniques have been widely used, and new methods have been developed.
Ultrasonic flow meters have advantages in some respects that are not comparable to other types of flow meters. For example, in contrast to electromagnetic flowmeters, ultrasonic flowmeters do not require any obstructions in the fluid and are therefore particularly suitable for measuring fluid flow in large bore pipes. In addition, the ultrasonic flowmeter has high measurement accuracy, is hardly interfered by various parameters of the measured medium, and can especially solve the problems of flow measurement of highly corrosive, non-conductive, radioactive and flammable and explosive mediums which cannot be measured by other meters.
There are several types of ultrasonic flow rate measuring instruments available, several of which are common:
portable ultrasonic flowmeter: the instrument generally adopts the principle of ultrasonic flow rate measurement, and can measure the flow rate of rivers, streams, irrigation channels and other occasions. The portable flow rate measuring instrument has the characteristics of portability, easiness in use, accuracy in measurement and the like, and is a preferred instrument for measuring the flow rate in the field.
Fixed ultrasonic flowmeter: such instruments are typically installed in fixed locations such as rivers, reservoirs, open channels, etc. for long term monitoring of flow rates. The method has the characteristics of high precision, high stability, capability of remotely transmitting data and the like, and is widely applied to the fields of hydrology, water conservancy, environmental protection and the like.
Ultrasonic Doppler flow velocity meter: the instrument calculates the flow velocity by measuring the frequency change of the scattered echo, has the characteristics of wide measuring range, high precision, no requirement on water quality and the like, and is suitable for measuring non-uniform flow and pulsating flow.
Ultrasonic anemometer: the instrument adopts the principle of measuring wind speed by ultrasonic wave, has the characteristics of portability, easy use, accurate measurement and the like, and is suitable for the fields of meteorological observation, environmental monitoring and the like.
However, current ultrasonic flow measurement techniques also suffer from some drawbacks, such as unstable flow rates: the flow rate is often unstable, and the ultrasonic flowmeter may be affected by each other to produce a larger measured value; abnormal signal transmission: if the ultrasonic flowmeter cannot normally transmit signals, measurement cannot be performed; environmental problems: the ultrasonic flowmeter needs to measure under proper environmental conditions, and high temperature, low temperature, humidity, noise and the like can affect the accuracy of the ultrasonic flowmeter.
Disclosure of Invention
The invention aims to provide a processing method for obtaining a flow velocity signal by using an ultrasonic reflection type flow velocity measuring instrument.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
a processing method for obtaining a flow velocity signal by using an ultrasonic reflection type flow velocity measuring instrument, wherein:
the ultrasonic reflection type flow velocity measuring instrument comprises an ultrasonic transducer I, an ultrasonic transducer II, a transducer collimation coupling component, a probe rod and a controller; the probe rod is a circular pipe fitting with a hollow inside; the front ends of the ultrasonic transducer I and the ultrasonic transducer II are respectively provided with a transducer collimation coupling component; the ultrasonic transducer I and the ultrasonic transducer II (2) are fixedly arranged at one end of the probe rod; the other end of the probe rod is a reflecting end, and an opening is arranged on the probe rod close to the reflecting end and is used as a measuring area; the ultrasonic transducer I and the ultrasonic transducer II are respectively externally connected with a controller;
the processing method comprises the following steps:
(a) The transmitting end and the measuring area of the probe rod extend into the flue to be measured, during forward measurement, the controller controls the ultrasonic transducer I to transmit high-frequency sound waves, long-distance low-loss conduction is realized after coupling collimation through the transducer collimation coupling component, the sound waves are transmitted to the reflecting end through the reverse wind direction of the measuring area, the reflected sound waves are reversely transmitted to the position of the ultrasonic transducer II, the sound wave signals are converted into electric signals through the ultrasonic transducer II, the electric signals are detected and identified, and the controller obtains the transmission time difference of the transmitted sound waves to the received signals through timing processing to be t 1 ；
(b) Knowing that the sound velocity is Vx, the wind speed is F, the included angle between the probe rod and the wind speed direction is theta, the total transmission path is S, the path of the measurement area is L, and the Doppler law is adopted
(c) During reverse measurement, the controller drives the ultrasonic transducer II to emit high-frequency sound waves, the high-frequency sound waves are transmitted to the reflecting end, the reflected sound waves are reversely transmitted to the position of the ultrasonic transducer I through the measuring area along the wind direction, the sound wave signals are converted into electric signals through the ultrasonic transducer I, and the controller obtains the transmission time difference of the emitted receiving signals through timing processing to be t 2 ；
(d) According to Doppler's law
(e) Thereby, the wind speed can be obtained
As a further explanation of the invention, the ultrasonic transducer I and the ultrasonic transducer II are arranged vertically at one end of the probe rod. Namely: the ultrasonic transducer I is arranged on the upper half part of one end of the probe rod, and the ultrasonic transducer II is arranged on the lower half part of one end of the probe rod.
As further illustration of the invention, the frequencies of the ultrasonic transducer I and the ultrasonic transducer II are 15-200 kHz, and the ultrasonic transducer I and the ultrasonic transducer II are mutually exchanged as transmitting and receiving sources.
As further described in the invention, the reflecting end is of a conical smooth surface structure, so that the sound wave transmission can be efficiently reflected, and the energy loss is reduced.
As a further illustration of the invention, the measuring region is a semicircular cut-out region and is a partial region through which the ultrasonic wave emitted by the ultrasonic transducer i passes. Except for the holes which need to be reserved in the conducting paths, the conducting paths are firmly welded; the side of the cutting area faces the wind direction when being installed, the probe rod is obliquely inserted into the flue, and the included angle between the probe rod and the wind speed direction is theta, so that the windward and upwind sections of ultrasonic conduction in the area are generated.
As a further illustration of the invention, the transducer collimating coupling component is a surface mounted graded index structure of an ultrasonic transducer. The transducer collimation coupling component can converge ultrasonic wave beam transmission, realize long-distance low-loss transmission and improve system detection precision; the surface of the transducer needs to be matched with the collimating structure in a nondestructive way, and couplants such as glycerin, silicone oil and the like are used.
As a further explanation of the invention, the single conduction receiving time of the ultrasonic transducer I and the ultrasonic transducer II is 1 ms-10 ms.
As a further explanation of the invention, the steps (a) - (e) are all calculated and processed by an embedded single chip microcomputer.
The invention has the advantages that:
the device has simple structure and low manufacturing cost, when in use, the reflecting end and the measuring area are only required to be placed in the flue at a certain inclination angle, the ultrasonic transducer is completely placed outside the flue, the special design of high-temperature resistant materials is not required, the design cost of the transducer is greatly reduced, and the influence of the high-temperature environment on the accuracy of ultrasonic measurement is avoided.
Drawings
FIG. 1 is a schematic diagram of a cross-sectional structure of an embodiment of the present invention.
Fig. 2 is a schematic external structure of an embodiment of the present invention.
Reference numerals: 1-ultrasonic transducer I, 2-ultrasonic transducer II, 3-transducer collimation coupling part, 4-probe rod, 5-reflecting end, 6-ultrasonic conduction path I, 7-ultrasonic conduction path II, 8-measuring area, 9-wind direction.
Detailed Description
The invention is further described below with reference to the accompanying drawings.
Examples:
a processing method for obtaining a flow velocity signal by using an ultrasonic reflection type flow velocity measuring instrument, wherein:
as shown in fig. 1, the ultrasonic reflection type flow velocity measuring instrument comprises an ultrasonic transducer I1, an ultrasonic transducer II 2, a transducer collimation coupling part 3, a probe rod 4 and a controller; the probe rod 4 is a circular pipe fitting with a hollow inside; the front ends of the ultrasonic transducer I1 and the ultrasonic transducer II 2 are respectively provided with a transducer collimation coupling part 3; the ultrasonic transducer I1 and the ultrasonic transducer II 2 are fixedly arranged at one end of the probe rod 4; the other end of the probe rod 4 is a reflecting end 5, and an opening is arranged on the probe rod close to the reflecting end and is used as a measuring area 8; the ultrasonic transducer I1 and the ultrasonic transducer II 2 are respectively externally connected with a controller;
as shown in fig. 2, the processing method includes the steps of:
(a) The transmitting end 5 and the measuring area 8 of the probe rod 4 extend into the flue to be measured, during forward measurement, the controller controls the ultrasonic transducer I1 to transmit high-frequency sound waves, long-distance low-loss conduction is realized after the coupling collimation of the transducer collimation coupling component 3, the sound waves are transmitted to the reflecting end 5 through the reverse wind direction of the measuring area 8, the reflected sound waves are reversely transmitted to the position of the ultrasonic transducer II 2, the ultrasonic transducer II 2 converts sound wave signals into electric signals, the electric signals are detected and identified, and the controller obtains the transmission time difference of the transmitted sound waves to the received signals through timing processing to be t 1 ；
(b) Knowing that the sound velocity is Vx, the wind speed is F, the included angle between the probe rod and the wind speed direction is theta, the total transmission path is S, the path of the measurement area is L, and the Doppler law is adopted
(c) During reverse measurement, the controller drives the ultrasonic transducer II 2 to emit high-frequency sound waves, the high-frequency sound waves are conducted to the reflecting end, the reflected sound waves are reversely conducted to be transmitted to the position of the ultrasonic transducer I1 along the wind direction through the measuring area 8, the sound wave signals are converted into electric signals through the ultrasonic transducer I1, and the controller obtains the transmission time difference of the transmitted signals to the received signals through timing processing to be t 2 ；
(d) According to Doppler's law
(e) Thereby, the wind speed can be obtained
The present embodiment further illustrates that the ultrasonic transducer i 1 and the ultrasonic transducer ii 2 are mounted at one end of the probe rod 4 in a vertically arranged manner.
This example further illustrates that the frequencies of the ultrasonic transducer I1 and the ultrasonic transducer II 2 are 15-200 kHz, and the ultrasonic transducer I1 and the ultrasonic transducer II 2 are exchanged with each other as transmitting and receiving sources.
The embodiment further illustrates that the reflecting end 5 has a conical light surface structure.
The present embodiment further illustrates that the measuring region 8 is a semicircular cut-out region and is a partial region through which the ultrasonic wave transmitted from the ultrasonic transducer i 1 passes.
This embodiment further illustrates that the transducer collimating coupling component 3 is a graded index structure with an ultrasonic transducer surface mounted.
This example further illustrates that the single conduction reception time of the ultrasonic transducer I1 and the ultrasonic transducer II 2 is 1ms to 10ms.
The embodiment further illustrates that the steps (a) - (e) are all calculated and processed by an embedded single chip microcomputer.
In this embodiment, as shown in fig. 1, the ultrasonic signal propagates in a reflection pattern through the ultrasonic transmission path i 6 and the ultrasonic transmission path ii 7, the length of the measurement area 8 is L, the probe 4 is inserted obliquely into the flue, and the angle between the wind speed direction is θ (as shown in fig. 2), thereby generating the upwind and upwind sections of the ultrasonic transmission in the area. The two transducers are sequentially used as transmitting and receiving signal modules, the time difference of two cycles of transmitting, receiving and transmitting is detected by the control main board, and finally the flow velocity value is obtained through processing.
It is to be understood that the above-described embodiments are merely illustrative of the invention and are not intended to limit the practice of the invention. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art; it is not necessary here nor is it exhaustive of all embodiments; and obvious variations or modifications thereof are contemplated as falling within the scope of the present invention.
Claims (8)
1. A processing method for obtaining a flow velocity signal by using an ultrasonic reflection type flow velocity measuring instrument is characterized in that:
the ultrasonic reflection type flow velocity measuring instrument comprises an ultrasonic transducer I (1), an ultrasonic transducer II (2), a transducer collimation coupling component (3), a probe rod (4) and a controller; the probe rod (4) is a circular pipe fitting with a hollow inside; the front ends of the ultrasonic transducer I (1) and the ultrasonic transducer II (2) are respectively provided with a transducer collimation coupling component (3); the ultrasonic transducer I (1) and the ultrasonic transducer II (2) are fixedly arranged at one end of the probe rod (4); the other end of the probe rod (4) is a reflecting end (5), and an opening is formed in the probe rod close to the reflecting end and is used as a measuring area (8); the ultrasonic transducer I (1) and the ultrasonic transducer II (2) are respectively externally connected with a controller;
the processing method comprises the following steps:
(a) The transmitting end (5) and the measuring area (8) of the probe rod (4) extend into the flue to be measured, during forward measurement, the controller controls the ultrasonic transducer I (1) to transmit high-frequency sound waves, long-distance low-loss conduction is realized after coupling collimation through the transducer collimation coupling component (3), the sound waves are transmitted to the reflecting end (5) through the measuring area (8) in the reverse wind direction, and are reversely conducted to the position of the ultrasonic transducer II (2) after reflection, the sound wave signals are converted into electric signals through the ultrasonic transducer II (2), the electric signals are detected and identified, and the controller obtains the transmission time difference of the transmitted signals to the receiving signals through timing processing to be t 1 ；
(b) Knowing that the sound velocity is Vx, the wind speed is F, the included angle between the probe rod and the wind speed direction is theta, the total transmission path is S, the path of the measurement area is L, and the Doppler law is adopted
(c) Reverse measurementWhen the ultrasonic wave signal is converted into an electric signal through the ultrasonic transducer I (1), the controller obtains the transmission time difference of the transmitted signal to the received signal as t through timing processing 2 ；
(d) According to Doppler's law
(e) Thereby, the wind speed can be obtained
2. The method for processing a flow rate signal obtained by an ultrasonic reflection type flow rate measuring instrument according to claim 1, wherein: the ultrasonic transducer I (1) and the ultrasonic transducer II (2) are arranged at one end of the probe rod (4) in an up-down vertical arrangement mode.
3. The processing method for obtaining a flow rate signal with an ultrasonic reflection type flow rate meter according to claim 2, wherein: the frequencies of the ultrasonic transducer I (1) and the ultrasonic transducer II (2) are 15-200 kHz, and the ultrasonic transducer I (1) and the ultrasonic transducer II (2) are mutually exchanged to serve as transmitting and receiving sources.
4. A method of processing a flow rate signal using an ultrasonic reflectometer as in claim 3, wherein: the reflecting end (5) is of a conical smooth surface structure.
5. The method for obtaining a flow rate signal using an ultrasonic reflection type flow rate meter according to claim 4, wherein: the measuring region (8) is a semicircular cut-out region and is a partial region through which an ultrasonic wave transmission path emitted by the ultrasonic transducer (I1) passes.
6. The method for obtaining a flow rate signal using an ultrasonic reflection type flow rate meter according to claim 5, wherein: the transducer collimation coupling component (3) is a graded index structural component arranged on the surface of the ultrasonic transducer.
7. The method for obtaining a flow rate signal using an ultrasonic reflection type flow rate meter according to claim 6, wherein: the single conduction receiving time of the ultrasonic transducer I (1) and the ultrasonic transducer II (2) is 1 ms-10 ms.
8. The method for processing a flow rate signal using an ultrasonic reflection type flow rate meter according to claim 7, wherein: the steps (a) - (e) are all calculated and processed through an embedded single chip microcomputer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311486081.6A CN117517706A (en) | 2023-11-09 | 2023-11-09 | Processing method for obtaining flow velocity signal by using ultrasonic reflection type flow velocity measuring instrument |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311486081.6A CN117517706A (en) | 2023-11-09 | 2023-11-09 | Processing method for obtaining flow velocity signal by using ultrasonic reflection type flow velocity measuring instrument |
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| CN117517706A true CN117517706A (en) | 2024-02-06 |
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| CN202311486081.6A Pending CN117517706A (en) | 2023-11-09 | 2023-11-09 | Processing method for obtaining flow velocity signal by using ultrasonic reflection type flow velocity measuring instrument |
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