RU171822U1 - On-board ultrasonic measuring instrument of speed of a current and an expense of water in an open reservoir - Google Patents

Abstract

The utility model relates to ultrasonic devices for measuring flow velocity and water flow in open water bodies, for example, in a river bed. The ultrasonic meter is made in the form of a radio-controlled small-sized measuring vessel with propulsion 18. A digital signal processing unit is installed on board the vessel, and an antenna unit of ultrasonic transducers is installed on the bottom of the vessel. The digital signal processing unit 1, mounted on board the vessel, comprises an automatic measurement control unit 8, an ultrasonic transmitter 4 of complex sounding signals (AC) with an analog output, a multichannel receiver 5 of response signals with an analog input and a digital output, mounted on a bi-directional interface bus 10 of coupling device 6 for digital processing of response signals, device 7 for binding measurements to terrain and a radio modem 9. The output of the transmitter 4 and the input of the receiver 5 through the antenna switch 3 is connected the antenna unit 11 of the ultrasonic transducers. The antenna unit 11 is made in the form of an equilateral pyramid 11, facing the apex towards the bottom of the reservoir. On the sides of the pyramid 11 are installed ultrasonic transducers 2 in the form of flat piezoceramic antennas or ultrasonic phased antenna arrays. Moreover, the ultrasonic transmitter of complex sounding signals (ZS) is configured to generate ZS in the frequency range from 100 to 3000 kHz and wobble the carrier frequency and the initial phase of the ZS by linear sequences of modulating pulses. The technical result of the invention is to improve the accuracy of measuring the flow velocity and flow rate of running water in an open reservoir. 8 s.p. f-ly, 2 ill.

Description

The utility model relates to ultrasonic devices for measuring the flow velocity and flow rate of water in open water bodies, for example, in a river or water channel.

Known ultrasonic devices / 1-6 / measuring the speed and flow of water in open water, based on ultrasonic sensing of the water column, receiving reflected signals (OS), measuring Doppler shifts of the carrier frequencies and phases of the OS, proportional to the speed of water flow, and calculating based on them the current parameters of the reservoir.

Closest to the claimed utility model for its intended purpose and technical essence is an onboard ultrasonic meter / 6 / for measuring the flow velocity and water flow in open water bodies.

A well-known onboard ultrasonic meter for the speed of flow and water flow in an open pond contains a digital signal processing unit connected via probing and reflected signals to the antenna unit of ultrasonic transducers.

Moreover, the digital signal processing unit includes programmatically interconnected digital ultrasonic wave transceivers, Doppler filters, an echo sounder, a sound velocity meter in water, a trigger, a drift angle meter, water multiplier, a correction signal generator, a depth counter, a Doppler signal processing unit, dividers integrating counter, as well as an indicator.

The antenna unit contains a sonar transducer and four sonar transducers oriented in pairs towards the bottom of the river and at an acute angle to the vertical plane. It is mounted on a fish-like cargo for towing with a cable across the course of the reservoir, and is connected by an electric cable to the on-board equipment located on the deck of the towing vessel. A hydrometric pinwheel and a sound velocity sensor in water are connected to the antenna unit, connected via signal outputs to the corresponding on-board equipment of the signal processing unit. The sound velocity sensor is made in the form of a cylinder with slots, in which a piezoelectric element and a reflector are placed.

The fish-like cargo - the carrier of the antennas and gauge sensors - is suspended in the water on a flexible winch cable of the ship's boom and is equipped with a water stabilizer in the shape of a fish tail.

A disadvantage of the known on-board ultrasonic meter / 6 / for measuring the flow velocity and water flow in open reservoirs is the reduced accuracy of measuring the average velocity of flowing water in a reservoir, associated with a reduced resolution of measurements based on an estimate of the Doppler frequency in the received spectrum of the reflected signals, with reduced accuracy drift measurements based on the registration of the speed of the surface water flow relative to the surface of the vessel with a hydrometer turntable. Another disadvantage of the known meter is the impossibility of taking measurements at shallow depths of water bodies due to insufficient resolution of the echo sounder and increased draft of a vessel carrying a boom and a fish-shaped load immersed in water with an antenna unit and sensors of measuring equipment.

The objective and technical result of the utility model is to increase the accuracy of measuring the flow velocity and water flow in an open reservoir.

The essence of the utility model.

The achievement of the claimed technical result and the solution of the problem is provided by the fact that the onboard ultrasonic flow velocity and water flow meter in an open reservoir contains a digital signal processing unit, connected via probing and reflected signals to the antenna unit of ultrasonic transducers.

According to a utility model, the ultrasonic meter is made in the form of a radio-controlled small-sized measuring vessel with a propulsion 18. A digital signal processing unit 1 is installed on board the vessel, and an antenna unit 11 of ultrasonic transducers is installed on the bottom of the vessel. The digital signal processing unit 1, installed on board the vessel, contains an automatic measurement control unit 8, an ultrasonic transmitter 4 of complex probing signals (AC) with an analog output, a multichannel receiver 5 of response signals (OS) with an analog input, mounted on a bi-directional interface bus 10 of pairing digital output, device 6 for digital processing of the OS, device 7 for binding measurements to the terrain and radio mode 9. The output of the transmitter 4 and the input of the receiver 5 through the antenna switch 3 is connected to the antenna eye 11 ultrasonic transducers. The antenna unit 11 is made in the form of an equilateral pyramid 11, facing the apex towards the bottom of the reservoir. On the sides of the pyramid 11 are installed ultrasonic transducers 2 in the form of flat piezoceramic antennas or ultrasonic phased antenna arrays. The device 7 binding measurements to the terrain is made in the form of a navigator, gyroscope, magnetic compass, accelerometer or GPS / GLONASS sensors. AP transmitter 4 and OS digital processing device 6 are respectively configured to generate an AP with pulse-code modulation (PCM) and the possibility of correlation processing the OS in the frequency range from 100 to 3000 kHz, wobble the carrier frequency and / or the initial phase of the AP with Barker codes, M -sequence, Jacobi codes, non-linear or additional sequences of modulating pulses. To measure the speed and flow rate of water in reservoirs at depths less than the draft of the vessel, it is additionally equipped with a retractable or self-moving piezoceramic antenna 2.

Such a constructive implementation of an on-board ultrasonic flow velocity and water flow meter in an open reservoir allows at each measurement step to make a rational choice of the meter operation mode depending on the current depth and water flow velocity. In this case, the coding of the initial phases of the carrier frequency of ultrasonic ES of probe pulses with Barker codes, M-sequence, Jacobi codes, non-linear or additional sequences of modulating pulses allows to eliminate the decorleling of signals, the ambiguity of their reading in range. As a result, the resolution of measurements of the current depth of the reservoir is brought to several millimeters, in contrast to the resolution (≥5 ... 10 cm) of the prototype / 6 /. Also, from units cm / s to 1-2 mm / s, the absolute error in calculating the current speed for small water flow rates in the presence of standing waves decreases. Accordingly, the accuracy of measuring the flow velocity and water flow in a reservoir increases. The range of application of the inventive meter for water flow rates in a reservoir of more than 1 m / s and a reservoir depth of more than 15 m is expanding.

The invention is illustrated in FIG. 1-3.

In FIG. 1 shows the design of a water-floating ultrasonic profilometer (VUP) - a flow velocity and water flow meter in an open reservoir mounted on a flat-bottomed radio-controlled boat with a block of ultrasonic rhombic antennas mounted on the bottom of the boat, in FIG. 2 is a view of the antenna unit from the side of its suspension to the bottom of the vessel, and in FIG. 3 - an algorithm for measuring the speed and flow rate of water in a reservoir using the specified OPS.

In the figures indicated:

1 - vessel measuring equipment carrier - floating ultrasonic profilometer (VUP);

2 - ultrasonic transducer (piezoceramic antenna);

3 - antenna switch;

4 - ultrasonic transmitter of sounding signals (ZS);

5 - multi-channel receiver of electrical response signals (OS) of ultrasonic frequency with a digital output;

6 - a device for digital processing of response signals (OS);

7 - device binding measurements to the terrain;

8 - block automatic control of measurements;

9 - a radio modem for transmitting measurement data;

10 - bidirectional interface bus interface;

11 - equilateral pyramid (the base of the block of piezoceramic antennas 2);

12 - a digital generator of sounding signals;

13 - digital-to-analog converter;

14 - power amplifier;

15 - calculator of the depth of the reservoir;

16 - controlled digital correlator;

17 - calculator of the current speed and flow rate of water in the reservoir;

18 - propulsion OPS.

The design of an onboard ultrasonic meter for the speed of flow and water flow in an open pond is disclosed by the example of a remotely controlled floating ultrasonic profilometer (VUP) developed by the applicant. The OPS contains a digital signal processing unit installed on board the small flat-bottomed vessel 1, then OPS 1, and on the bottom of the OPS 1 there is a block of piezoceramic antennas 2. Antennas 2 are connected through the antenna switch 3 to the output of the ultrasonic transmitter 4 of the probing signals (ZS) and the inputs of the ultrasonic multichannel receiver 5 echo signals - response signals (OS) reflected from the bottom of the reservoir, block 8 automatic measurement control and radio modem 9 for transmitting measurement data.

Moreover, the automatic measurement control unit 8 and the radio modem 9 are connected via signal and control inputs / outputs via a bi-directional interface bus 10 to the device 6 for digital processing of echo signals and an ultrasonic transmitter 4. The ultrasonic receiver 5 is made with a digital output connected to the first signal input of the device 6 digital processing of echo signals, the second signal input of which is connected to the device 7 binding measurements to the terrain. Piezoceramic antennas 2 are made in the form of flat antennas or phased antenna arrays mounted on the faces of an equilateral pyramid 11 facing the apex toward the bottom of the reservoir. The transmitter 4 of the probing signals comprises a digitally generated 12 amplitude probes, phase and phase-controlled digital generator 12, a digital-to-analog converter 13 and a power amplifier 14. The device 6 for digital processing of echo signals contains a series-connected calculator 15 of the depth of the reservoir, a controlled digital correlator 16 and a calculator 17 of the current speed and flow rate of water in the reservoir with reference to the geographical coordinates of the location of the vessel 1. Block 8 automatic control of measurements in executed in the form of a control microcomputer, and is equipped with a program for automatic measurement control, comparing the current values of the depth and speed of water in the reservoir with a threshold value and switching programs for the modulation of the digital generator 12 and the corresponding type of correlation processing in the digital correlator 16 when the comparison results are close to the threshold value. The digital generator 12 and the digital correlator 16 are configured to synchronously change the modulation mode of the AP and the correlation processing mode of the OS, respectively, depending on the parameters of the reservoir at the measurement site under the control of the microcomputer of unit 8. Generator 12 is configured to wobble and / or pulse code modulate the carrier frequency and / or the initial phase of the GC with Barker codes, M-sequence, Jacobi codes, non-linear or additional sequences of modulating pulses under control of block 8. Carrier frequency The probe signals of generator 12 were selected in the range of ultrasonic frequencies from 100 to 3000 kHz. To measure the speed and flow rate of water in reservoirs, at depths less than the draft of the vessel, the ultrasonic meter is additionally equipped with a retractable or self-moving piezoceramic antenna 2. Retractable piezoceramic antenna 2 is equipped with a cable for connecting to the antenna switch 3 of the meter. The self-propelled piezoceramic antenna 2 is equipped with a gasoline or electric propulsion device 18 and wireless Wi-Fi connection with a meter connected to the antenna switch 3. The device 7 binding measurements to the terrain is made in the form of a navigator, gyroscope, magnetic compass, accelerometer or GPS / GLONASS sensors.

According to FIG. 3 ultrasonic measurement of flow velocity and water flow in an open reservoir using OPS 1 is as follows.

OMP 1 is installed on the surface of a reservoir near one of the banks of its channel. Orient the direction of movement of the VUP 1 perpendicular to the direction of the flow of water in the reservoir. On-board equipment 2-17 VUP 1 serves power, for example, from an on-board battery or gasoline-driven generator. After reaching the operating mode of equipment 2-17, the propeller 18 is turned on. In this case, VIP 1 moves along the water in the direction of the opposite shore of the reservoir. At the same time, in the process of moving VUP 1, a step-by-step ultrasonic measurement of the reservoir parameters is performed, including the current depth Δdn, water velocity ΔV _n , flow ΔW _n , water and drift angle Δβ (n) of the VUP 1 by the water flow. At each step of the measurements, the probe signal generator (ZS) generates electric pulses of ultrasonic frequency in the range of carrier frequencies from 300 to 3000 kHz. These electrical surroundings through the antenna switch 3 are transmitted to the block of piezoceramic antennas 2, where they are converted based on the effect of electrostriction into the energy of mechanical vibrations of the ultrasonic frequency and longitudinal ultrasonic waves are emitted in the direction of the bottom of the reservoir. The ultrasonic waves ZS reflected from the bottom of the reservoir are received by antennas 2, converted into electric reflected signals (OS) of ultrasonic frequency and through the antenna switch 3 are transmitted to the ultrasonic multichannel receiver 5 of ultrasonic OS reflected from the bottom of the reservoir. In the receiver 5, the electrical OS is amplified, converted to digital form and transmitted to the device 6 for digital processing of echo signals. In the device 6, according to the OS delay relative to the OS, the current depth dn of the reservoir is determined, and the current velocity ΔVn of the water flow is determined from the phase correlation processing of the set of OS. The measurement data of the depth and speed of the water flow through the bus 10 are transmitted to the control unit 8. In block 8, a comparison is made of the numerical values of the depth Δdn and velocity ΔVn of the water flow with threshold values Δdn ^g ~ 2-6 m, ΔV _n ^g ~ 0.5-0.8 m / s and the optimal measurement mode and correlation processing of the OS from the point view of increasing the accuracy of measurements from the condition:

- (Δdn≥Δdn ^g m) ∩ (Vn≥ΔV _n ^g m / s) - “A” mode, including periodic emission of single-frequency ultrasonic pulses + pulse code modulation of the carrier frequency and / or the initial phase of the probing signals (ZS) + intrapulse correlation processing of response signals (OS) with a time interval within the pulse of 0.04 <ΔТ1 <0.4 ms;

- Other - Mode “B”, including periodic emission of single-frequency ultrasonic pulses with a difference in repetition periods ΔТ2 + inter-period correlation processing of response signals (OS).

Wherein:

the numerical value of Δβ (3 (n) drift of the vessel by the flow of water is determined on the basis of navigation measurements of the spatial position of the vessel;

in each measurement mode "A" and "B" produce separate accumulation and correlation processing of the reflected echo signals;

in “A” mode, the intrapulse correlation coefficient ρ _{ΔT1 is measured} ;

in the "B" mode - the inter-period correlation coefficient is calculated ρ _ΔT2 ;

in modes "A" and "B", the arguments arg (ρ _ΔT1 ) or arg (ρ _ΔT2 ) are _calculated ;

in modes "A" and "B", the current radial velocity V _{n of} the water flow is determined by the found value of the argument arg (ρ _ΔT1 ) or arg (ρ _ΔT2 ) of the correlation coefficient from the condition

where ΔTi is the time interval inside the pulse 0.04 <ΔT1 <0.4 ms for method "A" or the difference in the repetition periods of ultrasonic pulses ΔT2 in mode "B";

λ is the wavelength of ultrasonic radiation.

At a shallow depth of the reservoir (Δdn≤Δdn ^gr ) and at the same time increased water flow rate (ΔV _n ≥ΔV _n ^gr ), the control unit 8 automatically switches on the measurement mode “A”, otherwise - mode “B”. In mode "A" (Fig. 1) in transmitter 4, pulse-code modulation (PCM) of the CS carrier frequency is performed and two sequences of single-frequency PCM pulses are generated, with a difference of the repetition periods ΔT≥0.2 ms and with the frequency of electrical oscillations from the range ultrasonic frequencies from 300 to 3000 kHz. Formed in the transmitter 4, electrical ES through the antenna switch 3 are transmitted to the block of piezoceramic antennas 2, are converted due to the effect of electrostriction into mechanical vibrations and are emitted in the direction of the bottom of the reservoir in the form of ultrasonic longitudinal waves. Passing through the water column, emitted by ES and reflected OS with PCM modulation, Doppler shifts in frequency and phase are obtained, proportional to the velocity ΔV _{n of the} movement of water in the reservoir. OS with PCM modulation reflected from the bottom of the reservoir, carrying updated information about the current depth Δdn and velocity ΔV _{n of} the water flow, are received by piezoceramic antennas 2, converted into electric signals of ultrasonic frequency and transmitted through the antenna switch 3 to the corresponding receiving channels of the multi-channel receiver 5. V the receiver 5 with a digital output received PCM signals are amplified, converted to digital form and transmitted to the device 6 for digital processing of echo signals. In the device 6, switched on in the “A” mode for correlation processing of two sequences of single-frequency PCM pulses with a difference of the repetition periods ΔТ≥0.2 ms, a high-precision measurement of the current depth Δdn in calculator 15 and speed ΔV _{n is} performed (under the programmed control of unit 8) the flow of water in the correlator 16. in this case, correlator 6 calculates the intra-correlation coefficients ρ _T1 and ρ _T2 reflected PCM signals and then calculating mezhduperiodnogo their cross-correlation coefficient ρ _mod from the expression (8), and further - Population of the value of its argument arg (ρ _mod). From the found value of the argument arg (ρ _mod ), the cross-correlation coefficient from expression (10) determines the current radial velocity ΔV _{n of} the water flow and the current flow rate ΔW of water from expression (12).

With increased current depth of the reservoir (Δdn> Δdn ^rp ) and / or low current velocity of the water flow (ΔV _n <ΔV _n ^gr ), the “B” measurement mode is automatically activated (Fig. 1).

In the “B” mode of correlation processing in the digital generator 12, the type of modulation of the CS from PCM to wobble, for example, linear, of the carrier frequency of the CS changes, and in the digital correlator 16 the type of correlation processing is changed from intra-pulse to inter-period, the inter-period correlation coefficient ρ _{mod is} calculated from the expression (9). Next, the argument arg (ρ _mod ) of the cross-correlation coefficient is determined from the found value of ρ _mod , and from the expression (10), the current radial velocity ΔV _{n of} the water flow is determined and from expression (2) the current flow rate ΔWn of water

.

.

Regardless of the OS correlation processing mode used, the measurement of the drift angle Δβ (n) of the OPS 1 by the flow of water at each measurement step is made by the navigation equipment of the device 7 for measuring measurements to the terrain. As navigation equipment, a gyroscope, a magnetic compass, an accelerometer or a GPS / GLONASS sensor can be used.

At the next measurement step (n = n + 1, n≤N), the measurement process and storing the current values of the drift angle Δβ (n), the radial velocity ΔV _{n of} the water flow and the flow ΔW of water in the open reservoir is repeated.

Upon arrival of OPS 1 to the opposite shore (n> N), the process of ongoing measurements of the parameters of the reservoir during the movement of OPS 1 ends. Block 8 reads the data of step-by-step measurements, integrates them, and calculates the parameters of the reservoir channel, including the average velocity V, flow rate W of flowing water, length L, and area S of the transverse profile of the reservoir from the following expressions (3-7).

where ΔV _n , Δd _n , Δβ, ΔWn, are the current values of the water velocity ΔV _n , the thickness of the water layer Δd _n (current reservoir depth), the drift angle of the measurement line, the specific flow rate ΔWn of flowing water;

ΔL _n , Δt is the length of the spatial and temporal step along the line L of the measurement;

n, N - current number and total number of measurement steps;

Δt is the interval of ultrasonic measurements;

t _c - total time of ultrasonic measurements (time of movement of the vessel from one shore of the reservoir to the other);

Δβ (n) is the current drift angle of the vessel carrying the measuring equipment by the flow of water.

The results of step-by-step and final measurements are transmitted by block 8 through the bus 10 and the radio modem 9 to the final consumer of the parameters of the reservoir channel.

If it is impossible to approach VUP 1 to the opposite shore due to the depth of the reservoir, less precipitation VUP 1, the measurement of the final parameters of the reservoir is carried out by a retractable or self-moving piezoceramic antenna 2. The measurement data in this case is transmitted via a wired or wireless communication line connected to the antenna switch 3 of the meter .

The utility model is implemented as a prototype OPS. OPS allowed to bring the resolution of measurements of the depth of the reservoir to several millimeters, in contrast to the resolution (≥5 ... 10 cm) of the prototype / 6 /. Also, the absolute error in calculating the current water velocity to 1-2 mm / s for small water flow velocities in the presence of standing waves decreased from units cm / s. Accordingly, the accuracy of measuring the flow velocity and water flow in a reservoir has increased.

Sources of information taken into account when compiling the description

1. US 5531124, 07/02/1996.

2. JP 2676321, 07.25.1998.

3. Ultrasonic flowmeter UF-2100C, company Ultraflux Co.

4. DE 19722140, 12.11.1997.

5. RU 2193208, 07.20.2001.

6. RU 2045002, 09.27.1995.

7. Radio-electronic systems: Fundamentals of construction and theory. Directory. Edited by Y.D. Shirman. M .: Radio engineering, 2007.

Claims (9)

1. An on-board ultrasonic measuring instrument for the speed of flow and water flow in an open reservoir containing a digital signal processing unit, connected via probing and reflected signals to an antenna unit of ultrasonic transducers, characterized in that it is made in the form of a radio-controlled small-sized measuring vessel, on board which a digital a signal processing unit, and on its bottom is an antenna unit of ultrasonic transducers, and the digital signal processing unit mounted on board the vessel contains automatic measurement control unit, an ultrasonic transmitter of complex sounding signals (ES), a multi-channel response signal (OS) receiver, an OS digital processing device, a device for linking measurements to the terrain and a radio modem, interconnected via a bi-directional interface interface bus, and the antenna unit of ultrasonic transducers, mounted on the bottom of the measuring vessel - in the form of an equilateral pyramid facing the apex towards the bottom of the reservoir, on the lateral surfaces of which are installed sonic transducers connected through an antenna switch with the output of the transmitter of the ZS and the input of the receiver of the OS, and the ultrasonic transmitter of complex sounding signals (ZS) is configured to generate the ZS in the frequency range from 100 to 3000 kHz and wobble the carrier frequency and the initial phase of the ZS by linear sequences of modulating pulses . 2. The on-board ultrasonic meter according to claim 1, characterized in that the ultrasonic transducers mounted on the faces of the pyramid are made in the form of flat piezoceramic antennas or ultrasonic phased antenna arrays. 3. The on-board ultrasonic meter according to claim 1, characterized in that the automatic measurement control unit is made in the form of a control microcomputer equipped with a program for automatic measurement control, comparing current values of the depth and velocity of water in the reservoir with a threshold value and choosing a rational measurement mode. 4. The on-board ultrasonic meter according to claim 1, characterized in that the transmitter of the probing signals comprises a digitally generated probe generator in amplitude, frequency and phase, a digital-to-analog converter and a power amplifier. 5. The on-board ultrasonic meter according to claim 1, characterized in that the device for digital processing of echo signals contains a series-connected calculator of the depth of the reservoir, a controlled digital correlator and a calculator of the current speed and flow rate of the water in the reservoir with reference to the geographical coordinates of the vessel. 6. The on-board ultrasonic meter according to claim 1, characterized in that for measuring the speed and flow rate of water in bodies of water at depths less than the draft of the vessel, it is additionally equipped with a retractable or self-moving piezoceramic antenna. 7. The on-board ultrasonic meter according to claim 7, characterized in that the retractable piezoceramic antenna is equipped with a cable for connecting to the antenna switch of the meter. 8. The on-board ultrasonic meter according to claim 7, characterized in that the self-propelled piezoceramic antenna is equipped with a gasoline or electric propulsion device and wireless Wi-Fi connection with a meter connected to the antenna switch. 9. The on-board ultrasonic meter according to claim 1, characterized in that the device for linking measurements to the terrain is made in the form of a navigator, gyroscope, magnetic compass, accelerometer or GPS / GLONASS sensors.

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