A device and method for measuring the flow velocity of a vortex water area

Abstract

The present invention relates to a device and method for measuring the flow velocity of a vortex water area, which includes a signal transmitting module, a signal receiving module, a data acquisition module, a data operation module, and a result analysis module. The signal transmitting module generates an incident electrical signal and converts it into an incident acoustic signal to be transmitted to the water area to be measured to obtain a distorted acoustic signal. The signal receiving module receives the distorted acoustic signal and converts it into a distorted electrical signal. Then, the data acquisition module acquires the distorted electrical signal. The data operation module obtains the tangential flow velocity of the vortices on each preset measurement plane based on the incident electrical signal and the distorted electrical signal. Finally, the result analysis module obtains the velocity distribution curve of the vortex water area to be measured according to the tangential flow velocity. Compared with the prior art, the signal transmitting module and the signal receiving module of the present invention are arranged on both sides of the vortex water area to be measured, and through non-contact hydroacoustic flow velocity measurement, the interference of the vortex water area itself on the measurement result during measurement is avoided, and accurate measurement of the flow velocity in the vortex water area is achieved.

Description

Technical Field

[0001] The present invention relates to the field of flow velocity measurement, and particularly to a device and method for measuring the flow velocity of a vortex water area. Background Art

[0002] Vertical-axis vortices often form in front of the pressure-type water inlets of hydraulic structures, which is a relatively common harmful hydraulic phenomenon. Vertical-axis vortices have a certain damaging effect on water inlets and hydraulic devices, deteriorate the inlet flow pattern, reduce the flow capacity, decrease the power generation, and even damage hydraulic structures and water turbine units. Therefore, in hydraulic engineering, in order to better manage each water area reasonably, it is necessary to detect the flow velocity of the vortex water area where the vertical-axis vortex is located and conduct targeted management based on the detection results.

[0003] The commonly used measurement methods in current hydraulic measurements include the Doppler method and the particle image velocimetry method. Among them, the Doppler method measures the flow velocity at the point where the probe is located by using the Doppler effect of an acoustic / optical Doppler velocimeter. The measurement range is small, and it belongs to single-point contact measurement. Since there are differences in the flow velocities between the vortex center and both sides of the vortex water area, multiple points often need to be detected during measurement. However, the measurement operation of contact measurement itself will interfere with the flow field and affect the measurement accuracy; the particle image velocimetry method needs to add tracer particles to the measured flow field and obtain the flow field velocity distribution by processing the moving images of the particles. It belongs to full-field non-contact measurement, but it cannot cope with complex outdoor environments. In the complex environment of the vortex water area, the movement trajectories of tracer particles are relatively complex, which will affect the measurement accuracy, and the tracer particles will also cause water source pollution. Therefore, the existing hydraulic measurement methods all have the technical problem that they will be affected by the complexity of the vortex water area, resulting in inaccurate measurement results during vortex water area measurement. Summary of the Invention

[0004] In view of this, it is necessary to provide a device and method for measuring the flow velocity of a vortex water area to solve the technical problem in the prior art that the measurement method is affected by the complexity of the vortex water area, resulting in inaccurate measurement results.

[0005] To solve the above technical problems, the present invention adopts the following technical solutions:

[0006] In a first aspect, the present invention provides a device for measuring the flow velocity of a vortex water area, including a signal transmitting module, a signal receiving module, a data acquisition module, a data operation module, and a result analysis module. The signal receiving module is connected to the data acquisition module, and the data acquisition module is connected to the data operation module; the data operation module is connected to the result analysis module, where;

[0007] The signal transmitting module is used to generate an incident electrical signal, convert the incident electrical signal into an incident acoustic signal, and transmit the incident acoustic signal to the measured vortex water area to obtain a distorted acoustic signal of the measured vortex water area;

[0008] The signal receiving module is used to receive the distorted acoustic signal and convert the distorted acoustic signal into a distorted electrical signal;

[0009] The data acquisition module is used to acquire the distorted electrical signal;

[0010] The data operation module is used to obtain the tangential flow velocity of the vortices on each preset measurement plane of the measured vortex water area according to the incident electrical signal and the distorted electrical signal;

[0011] The result analysis module is used to obtain the velocity distribution curve of the measured vortex water area according to the tangential flow velocity.

[0012] Further, the signal transmitting module includes a signal generator and a plurality of transmitting sensors, the signal receiving module includes a plurality of receiving sensors, each transmitting sensor corresponds to a receiving sensor and a preset measurement plane, the transmitting sensor array composed of a plurality of transmitting sensors and the receiving sensor array composed of a plurality of receiving sensors are arranged in parallel on both sides of the measured vortex water area, and the directivities of each transmitting sensor and the corresponding receiving sensor are opposite on both sides of the measured vortex water area.

[0013] Further, both the transmitting sensor array and the receiving sensor array are composed of sensor probes and array element fixing devices to form sensor array elements, and the sensor arrays are assembled from a plurality of sensor array elements.

[0014] In a second aspect, the present invention also provides a method for measuring the flow velocity of a vortex water area, which is applied to the above-mentioned vortex water area flow velocity measuring device, and the method includes:

[0015] Generate an incident electrical signal, convert the incident electrical signal into an incident acoustic signal, and transmit the incident acoustic signal to the measured vortex water area to obtain a distorted acoustic signal of the measured vortex water area;

[0016] Receive the distorted acoustic signal and convert the distorted acoustic signal into a distorted electrical signal;

[0017] Acquire the distorted electrical signal;

[0018] According to the incident electrical signal and the distorted electrical signal, obtain the tangential flow velocity of the vortices on each preset measurement plane of the measured vortex water area;

[0019] According to the tangential flow velocity, obtain the velocity distribution curve of the measured vortex water area.

[0020] Further, generating an incident electrical signal, converting the incident electrical signal into an incident acoustic signal, and transmitting the incident acoustic signal to the measured vortex water area to obtain a distorted acoustic signal of the measured vortex water area includes:

[0021] Determining the array size and the distance between array elements of the transmitting sensor array and the receiving sensor array according to the width of the measured vortex water area;

[0022] Determining the frequency of the incident electrical signal according to the array size and the distance between array elements;

[0023] Generating an incident electrical signal with a corresponding frequency based on a signal generator and transmitting the incident electrical signal to the transmitting sensor;

[0024] Converting the incident electrical signal into an incident acoustic signal based on the transmitting sensor and emitting the incident acoustic signal to the measured vortex water area, and a vortex-acoustic coupling effect is generated after the incident acoustic signal passes through the measured vortex water area to obtain a distorted acoustic signal of the measured vortex water area.

[0025] Further, the formula for determining the frequency of the incident electrical signal according to the width of the measured vortex water area is:

[0026]

[0027] In the formula, λ is the wavelength, c is the sound speed in water, L is the array size, and d is the distance between array elements.

[0028] Further, obtaining the velocity distribution of each preset measurement plane in the measured vortex water area according to the incident electrical signal and the distorted electrical signal includes:

[0029] Determining the predicted acoustic wave phase and the actual acoustic wave phase of each preset measurement plane according to the incident electrical signal and the distorted electrical signal;

[0030] Determining the acoustic wave time delay of each preset measurement plane according to the predicted acoustic wave phase and the actual acoustic wave phase;

[0031] Determining the tangential flow velocity of the vortex at each preset measurement plane according to the acoustic wave time delay.

[0032] Further, the formula for determining the tangential flow velocity of the vortex at each preset measurement plane according to the acoustic wave time delay is:

[0033]

[0034] Where δt is the acoustic wave time delay, c is the sound speed in water, u is the tangential flow velocity of the vortex at the preset measurement plane, n is the direction vector of the acoustic wave, and 1 and 2 in the integral formula respectively represent the positions of the transmitting sensor and the receiving sensor.

[0035] Further, obtaining the velocity distribution curve of the measured vortex water area based on the tangential flow velocity includes:

[0036] Constructing a scatter plot of the velocity distribution coordinate system of the measured vortex water area according to the tangential flow velocities of the vortices on each preset measurement plane;

[0037] Obtaining the velocity distribution curve of the measured vortex water area according to the scatter plot of the velocity distribution coordinate system.

[0038] Further, constructing the velocity distribution coordinate system of the measured vortex water area according to the tangential flow velocities of the vortices on each preset measurement plane includes:

[0039] Taking the position of the preset measurement plane at the middle position as the abscissa origin and the corresponding tangential flow velocity as the ordinate origin to construct the velocity distribution coordinate system;

[0040] Determining the axis positions corresponding to each preset measurement plane according to the relative positions and relative tangential flow velocities of each preset measurement plane and the preset measurement plane at the central position, and constructing a scatter plot of the velocity distribution coordinate system.

[0041] The present invention provides a vortex water area flow velocity measurement device and method. It generates an incident electrical signal through a signal transmission module and converts it into an incident acoustic signal to transmit to the measured water area to obtain a distorted acoustic signal. Then, it receives the distorted acoustic signal through a signal reception module and converts it into a distorted electrical signal. Then, it acquires the distorted electrical signal through a data acquisition module. Then, it obtains the tangential flow velocities of the vortices on each preset measurement plane of the measured vortex water area through a data operation module according to the incident electrical signal and the distorted electrical signal. Finally, it obtains the velocity distribution curve of the measured vortex water area through a result analysis module according to the tangential flow velocity. Compared with the prior art, the signal transmission module and the signal reception module of the present invention are arranged on both sides of the measured vortex water area. Through non-contact hydroacoustic flow velocity measurement, it avoids the interference of the vortex water area itself on the measurement result during the measurement process and realizes accurate measurement of the flow velocity in the vortex water area. Description of the Drawings

[0042] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those skilled in the art, without creative efforts, other drawings can be obtained according to these drawings.

[0043] Figure 1 It is a schematic structural diagram of an embodiment of the vortex water area flow velocity measurement device provided by the present invention;

[0044] Figure 2 It is a schematic structural diagram of the sensor array of the embodiment of the present invention;

[0045] Figure 3Schematic flowchart of an embodiment of the vortex water flow velocity measurement method provided by the present invention;

[0046] Figure 4 Schematic diagram of the theory of vortex-acoustic coupling effect according to an embodiment of the present invention;

[0047] Figure 5 Curve graph of the measured vortex water area velocity distribution according to an embodiment of the present invention. Detailed implementation manners

[0048] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of the present invention.

[0049] It should be understood that the attached drawings of the schematic diagrams are not drawn according to the actual scale. The flowcharts used in the present invention show the operations implemented according to some embodiments of the present invention. It should be understood that the operations in the flowchart may not be implemented in sequence, and the steps without logical context relationships may be reversed or implemented simultaneously. In addition, those skilled in the art can add one or more other operations to the flowchart or remove one or more operations from the flowchart under the guidance of the content of the present invention.

[0050] Some of the block diagrams shown in the attached drawings are functional entities, which do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software form, or implemented in one or more hardware modules or integrated circuits, or implemented in different networks and / or processor systems and / or microcontroller systems.

[0051] Referring to "embodiment" in this article means that the specific features, structures or characteristics described in combination with the embodiment can be included in at least one embodiment of the present invention. The appearance of this phrase in various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0052] In combination with Figure 1As shown in the figure, in a specific embodiment of the present invention, a vortex water area flow velocity measuring device is disclosed, which includes a signal transmitting module 110, a signal receiving module 120, a data acquisition module 130, a data operation module 140, and a result analysis module 150. The signal receiving module 120 is connected to the data acquisition module 130, and the data acquisition module 130 is connected to the data operation module 140; the data operation module 140 is connected to the result analysis module 150, where;

[0053] The signal transmitting module 110 is configured to generate an incident electrical signal, convert the incident electrical signal into an incident acoustic signal, and transmit the incident acoustic signal to the measured vortex water area to obtain a distorted acoustic signal of the measured vortex water area;

[0054] The signal receiving module 120 is configured to receive the distorted acoustic signal and convert the distorted acoustic signal into a distorted electrical signal;

[0055] The data acquisition module 130 is configured to acquire the distorted electrical signal;

[0056] The data operation module 140 is configured to obtain the tangential flow velocity of the vortices on each preset measurement plane of the measured vortex water area according to the incident electrical signal and the distorted electrical signal;

[0057] The result analysis module 150 is configured to obtain the velocity distribution curve of the measured vortex water area according to the tangential flow velocity.

[0058] The present invention provides a vortex water area flow velocity measuring device. The signal transmitting module 110 generates an incident electrical signal and converts it into an incident acoustic signal, which is transmitted to the measured water area to obtain a distorted acoustic signal. Then, the signal receiving module 120 receives the distorted acoustic signal and converts it into a distorted electrical signal. Then, the data acquisition module 130 acquires the distorted electrical signal. Then, the data operation module 140 obtains the tangential flow velocity of the vortices on each preset measurement plane of the measured vortex water area according to the incident electrical signal and the distorted electrical signal. Finally, the result analysis module 150 obtains the velocity distribution curve of the measured vortex water area according to the tangential flow velocity. Compared with the prior art, the signal transmitting module 110 and the signal receiving module 120 of the present invention are arranged on both sides of the measured vortex water area. Through non-contact hydroacoustic flow velocity measurement, the interference of the vortex water area itself on the measurement result during the measurement process is avoided, and accurate measurement of the flow velocity in the vortex water area is achieved.

[0059] In a specific embodiment of the present invention, the signal transmitting module 110 in this embodiment includes a signal generator and a plurality of transmitting sensors, and the signal receiving module 120 includes a plurality of receiving sensors, as Figure 2 shown Figure 2It is a schematic structural diagram of a sensor array. Each transmitting sensor 1130 corresponds to a receiving sensor 1140 and a preset measurement plane (i.e., the dotted line between the transmitting sensor 1130 and the receiving sensor 1140). The transmitting sensor array 1110 composed of multiple transmitting sensors 1130 and the receiving sensor array 1120 composed of multiple receiving sensors 1140 are arranged in parallel on both sides of the measured vortex water area, and each transmitting sensor 1130 and the corresponding receiving sensor 1140 are directionally opposite on both sides of the measured vortex water area.

[0060] It should be understood that Figure 2 This is only a structural diagram of a sensor array in an embodiment of the present invention. According to the needs of the actual vortex water area, more sensor arrays of other sizes can also be assembled.

[0061] Specifically, since the water flow velocities from the center to both sides of the vortex are different, several preset measurement planes need to be set, and the corresponding transmitting sensors and receiving sensors are used to measure in sequence to obtain the flow velocities of each part of the vortex water area.

[0062] In a specific embodiment of the present invention, both the transmitting sensor array and the receiving sensor array are composed of sensor probes and array element fixing devices to form sensor array elements, and the sensor array is assembled from multiple sensor array elements.

[0063] In order to better implement the vortex water area flow velocity measuring device in the embodiments of the present invention, correspondingly, based on the vortex water area flow velocity measuring device, as Figure 3 shown, Figure 3 This is a schematic flow chart of an embodiment of the vortex water area flow velocity measuring method provided by the present invention. An embodiment of the vortex water area flow velocity measuring method provided by the present invention includes:

[0064] S301. Generate an incident electrical signal, convert the incident electrical signal into an incident acoustic signal, and transmit the incident acoustic signal to the measured vortex water area to obtain a distorted acoustic signal of the measured vortex water area;

[0065] S302. Receive the distorted acoustic signal and convert the distorted acoustic signal into a distorted electrical signal;

[0066] S303. Collect the distorted electrical signal;

[0067] S304. According to the incident electrical signal and the distorted electrical signal, obtain the tangential flow velocity of the vortex on each preset measurement plane of the measured vortex water area;

[0068] S305. Obtain the velocity distribution curve of the measured vortex water area according to the tangential flow velocity.

[0069] Compared with the prior art, the present invention arranges the signal transmitting module 110 and the signal receiving module 120 on both sides of the measured vortex water area. The predicted acoustic wave phase is determined according to the incident electrical signal, and the actual acoustic wave phase is determined according to the distorted electrical signal. The acoustic wave time delay is obtained by calculating the phase difference between the actual acoustic wave phase and the predicted acoustic wave phase. The tangential velocity of the preset measurement plane is calculated through the acoustic wave time delay, and the velocity distribution curve of the vortex water area is constructed according to the tangential velocities of the preset measurement planes. Compared with the prior art, the present invention avoids the interference of the vortex water area itself on the measurement result during the measurement process and realizes the accurate measurement of the flow velocity in the vortex water area.

[0070] Specifically, during the measurement process, after the transmitting sensor emits an acoustic signal to the measured vortex water area, the sound will generate a distorted acoustic wave due to the vortex-acoustic coupling effect when propagating in the measured vortex water area, and the propagation speed will be affected by the vortex. As Figure 4 shown, Figure 4 is a schematic diagram of the vortex-acoustic coupling effect theory. Under the action of the vortex, the propagation speed of the acoustic wave changes, showing that the sound speed accelerates in the downstream area and decelerates in the upstream area. Eventually, at the receiving end, the phase of the acoustic wave waveform is distorted, that is, the vortex-acoustic coupling phenomenon occurs. The acoustic wave time delay caused by the flow of the vortex water area is determined according to the phase distortion, and the tangential velocity of the measurement plane corresponding to the acoustic wave is calculated.

[0071] In a specific embodiment of the present invention, an incident electrical signal is generated, the incident electrical signal is converted into an incident acoustic signal, and the incident acoustic signal is transmitted to the measured vortex water area to obtain a distorted acoustic signal of the measured vortex water area, including:

[0072] Determine the array size and the distance between array elements of the transmitting sensor array and the receiving sensor array according to the width of the measured vortex water area;

[0073] Determine the frequency of the incident electrical signal according to the array size and the distance between array elements;

[0074] Generate an incident electrical signal with a corresponding frequency based on a signal generator and send the incident electrical signal to the transmitting sensor;

[0075] Based on the transmitting sensor, convert the incident electrical signal into an incident acoustic signal and emit the incident acoustic signal to the measured vortex water area. After passing through the measured vortex water area, the incident acoustic signal generates a vortex-acoustic coupling effect to obtain a distorted acoustic signal of the measured vortex water area.

[0076] In a specific embodiment of the present invention, the formula for determining the frequency of the incident electrical signal according to the width of the measured vortex water area is:

[0077]

[0078] In the formula, λ is the wavelength, c is the sound speed in water, L is the array size, and d is the distance between array elements.

[0079] Among them, a wavelength greater than d / 2 can avoid mutual interference between each group of transmitting sensors and receiving sensors, and a wavelength less than L can avoid multiple spectral peaks appearing in the obtained waveform diagram. Arbitrarily determine a fixed wavelength within the range of d / 2 and L as the wavelength of the incident acoustic signal emitted by each transmitting sensor, and determine the frequencies of the incident acoustic signal and the incident electrical signal according to the wavelength. The present invention determines the frequency of the incident electrical signal through the array size L and the distance d between array elements, which can not only adapt to vortex waters of different sizes but also avoid mutual interference of each acoustic wave when each receiving sensor receives distorted acoustic signals.

[0080] Specifically, when a vortex is detected at a water conservancy project, a sensor array that can completely cover its size is assembled according to the vortex size. According to the array size L of the sensor array and the distance d between array elements, determine the range of the wavelength λ of the incident acoustic signal, and take a wavelength λ within the range as the wavelength of the incident acoustic signal. Then, according to the conversion formula between wavelength and frequency, obtain the frequency f of the transmitted acoustic signal, that is, the transmitted electrical signal. Then, the signal generator emits an incident electrical signal with the frequency f to the transmitting sensor, and the transmitting sensor converts the incident electrical signal into an incident acoustic signal and emits it to the water area to be measured. After passing through the water area to be measured, the incident acoustic signal generates a vortex-acoustic coupling effect to obtain a distorted acoustic signal.

[0081] In a specific embodiment of the present invention, obtaining the tangential velocity of each preset measurement plane of the vortex water area to be measured according to the incident electrical signal and the distorted electrical signal includes:

[0082] Determine the predicted acoustic wave phase and the actual acoustic wave phase of each preset measurement plane according to the incident electrical signal and the distorted electrical signal;

[0083] Determine the acoustic wave time delay of each preset measurement plane according to the predicted acoustic wave phase and the actual acoustic wave phase;

[0084] Determine the tangential flow velocity of the vortex of each preset measurement plane according to the acoustic wave time delay.

[0085] Compared with the prior art, in the Doppler method of single-point contact measurement, the measurement error is caused by contacting the vortex flow field itself, and the particle image velocimetry method of full-field non-contact measurement cannot be used in the complex environment of outdoor vortex waters. The solution of the present invention can, without contacting the vortex water area, according to the principle that the vortex-acoustic coupling phenomenon will occur in the vortex water area, resulting in phase distortion of the received acoustic signal, and by setting several measurement planes, calculate the flow velocities of each part of the vortex water area, achieving the technical effect of full-field non-contact measurement of the flow velocity of the vortex water area that can adapt to various complex environments.

[0086] In a specific embodiment of the present invention, the formula for determining the tangential flow velocity of the vortex of each preset measurement plane according to the acoustic wave time delay is:

[0087]

[0088] Where δt is the acoustic wave time delay, c is the sound speed in water, u is the tangential flow velocity of the vortex on the preset measurement plane, n is the direction vector of the acoustic wave, and 1 and 2 in the integral formula represent the positions of the transmitting sensor and the receiving sensor respectively.

[0089] Specifically, assuming that the propagation times of the acoustic wave are t0 and t in the cases of no vortex and with vortex respectively, then the acoustic wave time delay δt = t - t0. In the case of no vortex, the predicted propagation time is:

[0090]

[0091] In the case of having a vortex, the sound speed in water is v = c + u·n, where u is the tangential flow velocity of the vortex on the preset measurement plane, n is the direction vector of the acoustic wave, and c is the sound speed in water, taking 1500 m / s in an isentropic adiabatic water medium. The propagation time of the acoustic wave is:

[0092]

[0093] And the acoustic wave time delay caused by the vortex - acoustic coupling effect, that is, the difference in the acoustic wave propagation times in the cases of no vortex and with vortex, is expressed as:

[0094]

[0095] Performing a series expansion on the expression and omitting the high - order small quantities, we get:

[0096]

[0097] Then when the acoustic wave time delay δt and the positions of the transmitting sensor and the receiving sensor are known, the tangential flow velocity of the preset measurement plane can be obtained according to the above formula.

[0098] In a specific embodiment of the present invention, obtaining the velocity distribution curve of the measured vortex water area according to the tangential flow velocity includes:

[0099] Constructing a scatter plot of the velocity distribution coordinate system of the measured vortex water area according to the tangential flow velocities of the vortices on each preset measurement plane;

[0100] Obtaining the velocity distribution curve of the measured vortex water area according to the scatter plot of the velocity distribution coordinate system.

[0101] In a specific embodiment of the present invention, constructing the velocity distribution coordinate system of the measured vortex water area according to the tangential flow velocities of the vortices on each preset measurement plane includes:

[0102] Taking the position of the preset measurement plane at the middle position as the abscissa origin and the corresponding tangential flow velocity as the ordinate origin to construct the velocity distribution coordinate system;

[0103] Determine the coordinate axis positions corresponding to each preset measurement plane based on the relative positions and relative tangential flow velocities of the preset measurement planes and the preset measurement plane at the central position, and construct a scatter plot of the velocity distribution coordinate system.

[0104] Specifically, use the position of the preset measurement plane at the middle position as the origin of the abscissa, and the corresponding tangential flow velocity as the origin of the ordinate to construct a velocity distribution coordinate system. Determine the abscissa and ordinate in the corresponding coordinate system according to the relative positions of each preset measurement plane and the tangential flow velocities of the vortices of each preset measurement plane obtained, and construct a scatter plot of the velocity distribution coordinate system based on the coordinates corresponding to each preset measurement plane. At the same time, as a preferred embodiment, the ordinate corresponding to the preset measurement plane at the vortex center position can also be corrected and adjusted according to the fact that the flow velocity at the vortex center position is 0, and the other coordinates are adaptively adjusted according to the relative positions with the coordinate origin to eliminate the value error of the sound speed c in water in actual measurement.

[0105] Then perform curve fitting on the coordinate scatter points in the scatter plot of the velocity distribution coordinate system to obtain the velocity distribution curve of the measured vortex water area, as Figure 5 shown in the velocity distribution curve graph of the measured vortex water area obtained in the embodiment of the present invention.

[0106] In summary, the present invention generates an incident electrical signal through the signal transmission module and converts it into an incident acoustic signal to transmit to the measured water area to obtain a distorted acoustic signal, then receives the distorted acoustic signal through the signal reception module and converts it into a distorted electrical signal, then collects the distorted electrical signal through the data acquisition module, and then obtains the tangential flow velocities of the vortices of each preset measurement plane in the measured vortex water area through the data operation module according to the incident electrical signal and the distorted electrical signal. Finally, the result analysis module obtains the velocity distribution curve of the measured vortex water area according to the tangential flow velocities. Compared with the prior art, the signal transmission module and the signal reception module of the present invention are arranged on both sides of the measured vortex water area, and through non-contact hydroacoustic velocity measurement, the interference of the vortex water area itself on the measurement result during the measurement process is avoided; the frequency of the incident electrical signal is determined by the array size L and the distance d between array elements, which can not only adapt to vortex water areas of different sizes, but also avoid the mutual interference of each acoustic wave when each receiving sensor receives the distorted acoustic signal; according to the principle of vortex-acoustic coupling phenomenon, which causes phase distortion of the received acoustic signal, by setting several measurement planes, the flow velocities of each part of the vortex water area are calculated, achieving the technical effect of full-field non-contact velocity measurement of the vortex water area adaptable to various complex environments.

[0107] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A vortex water area flow velocity measuring device, characterized in that, It includes a signal transmitting module, a signal receiving module, a data acquisition module, a data operation module and a result analysis module. The signal receiving module is connected to the data acquisition module, and the data acquisition module is connected to the data operation module; the data operation module is connected to the result analysis module, where; The signal transmitting module is used to generate an incident electrical signal, convert the incident electrical signal into an incident acoustic signal, and transmit the incident acoustic signal to the measured vortex water area to obtain a distorted acoustic signal of the measured vortex water area; The signal receiving module is used to receive the distorted acoustic signal and convert the distorted acoustic signal into a distorted electrical signal; The data acquisition module is used to acquire the distorted electrical signal; The data operation module is used to determine the predicted acoustic wave phase and the actual acoustic wave phase of each preset measurement surface according to the incident electrical signal and the distorted electrical signal; determine the acoustic wave time delay of each preset measurement surface according to the predicted acoustic wave phase and the actual acoustic wave phase; determine the tangential velocity of the vortex of each preset measurement surface according to the acoustic wave time delay; Wherein, the formula for determining the tangential velocity of the vortex of each preset measurement surface according to the acoustic wave time delay is: wherein is the acoustic wave time delay, is the sound speed in water, is the tangential flow velocity of the vortex on the preset measurement surface, is the direction vector of the acoustic wave, and 1 and 2 in the integral formula respectively represent the positions of the transmitting sensor and the receiving sensor; The result analysis module is used to obtain the velocity distribution curve of the measured vortex water area according to the tangential velocity.

2. The vortex water area flow velocity measuring device according to claim 1, characterized in that, The signal transmitting module includes a signal generator and multiple transmitting sensors. The signal receiving module includes multiple receiving sensors. Each transmitting sensor corresponds to a receiving sensor and a preset measurement surface. The transmitting sensor array composed of multiple transmitting sensors and the receiving sensor array composed of multiple receiving sensors are arranged in parallel on both sides of the measured vortex water area, and the directivities of each transmitting sensor and the corresponding receiving sensor are opposite on both sides of the measured vortex water area.

3. The vortex water area flow velocity measuring device according to claim 2, characterized in that, Both the transmitting sensor array and the receiving sensor array are composed of sensor probes and array element fixing devices to form sensor array elements, and the sensor arrays are assembled by multiple sensor array elements.

4. A method for measuring the flow velocity of a vortex water area, which is applied to the vortex water area flow velocity measuring device described in any one of claims 1-3, and is characterized in that, The method includes: Generating an incident electrical signal, converting the incident electrical signal into an incident acoustic signal, and transmitting the incident acoustic signal to the measured vortex water area to obtain a distorted acoustic signal of the measured vortex water area; Receiving the distorted acoustic signal and converting the distorted acoustic signal into a distorted electrical signal; Acquiring the distorted electrical signal; Determining the predicted acoustic wave phase and the actual acoustic wave phase of each preset measurement surface according to the incident electrical signal and the distorted electrical signal; determining the acoustic wave time delay of each preset measurement surface according to the predicted acoustic wave phase and the actual acoustic wave phase; determining the tangential velocity of the vortex of each preset measurement surface according to the acoustic wave time delay; Wherein, the formula for determining the tangential velocity of the vortex of each preset measurement surface according to the acoustic wave time delay is: wherein is the acoustic wave time delay, is the sound speed in water, is the tangential flow velocity of the vortex on the preset measurement surface, is the direction vector of the acoustic wave, and 1 and 2 in the integral formula respectively represent the positions of the transmitting sensor and the receiving sensor; Obtaining the velocity distribution curve of the measured vortex water area according to the tangential velocity.

5. The vortex water area flow velocity measurement method according to claim 4, characterized in that, The generating an incident electrical signal, converting the incident electrical signal into an incident acoustic signal, and transmitting the incident acoustic signal to the measured vortex water area to obtain a distorted acoustic signal of the measured vortex water area includes: Determining the array size and the distance between array elements of the transmitting sensor array and the receiving sensor array according to the width of the measured vortex water area; Determining the frequency of the incident electrical signal according to the array size and the distance between array elements; Generate an incident electrical signal corresponding to a frequency based on a signal generator and send the incident electrical signal to the transmitting sensor; Based on the transmitting sensor, convert the incident electrical signal into an incident acoustic signal and send the incident acoustic signal to the measured vortex water area. After passing through the measured vortex water area, the incident acoustic signal generates a vortex-acoustic coupling effect to obtain a distorted acoustic signal of the measured vortex water area.

6. The vortex water area flow velocity measurement method according to claim 5, characterized in that, The formula for determining the frequency of the incident electrical signal according to the width of the measured vortex water area is: Wherein, is the wavelength, is the sound speed in water, is the array size, is the distance between array elements.

7. The method for measuring the flow velocity of a vortex water area according to claim 4, characterized in that The method for obtaining the velocity distribution curve of the measured vortex water area according to the tangential velocity includes: Construct a scatter plot of the velocity distribution coordinate system of the measured vortex water area according to the tangential velocities of the vortices on each preset measurement plane; Obtain the velocity distribution curve of the measured vortex water area according to the scatter plot of the velocity distribution coordinate system.

8. The vortex water area flow velocity measurement method according to claim 7, characterized in that, The method for constructing the velocity distribution coordinate system of the measured vortex water area according to the tangential velocities of the vortices on each preset measurement plane includes: Take the position of the preset measurement plane at the middle position as the origin of the abscissa and the corresponding tangential velocity as the origin of the ordinate to construct a velocity distribution coordinate system; Determine the axis positions corresponding to each preset measurement plane according to the relative positions and relative tangential velocities of each preset measurement plane and the preset measurement plane at the central position, and construct a scatter plot of the velocity distribution coordinate system.

Images