Detailed Description
The technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the drawings in the embodiments of the present disclosure, and it is obvious that the described embodiments are some, but not all embodiments of the present disclosure. All other embodiments, which can be derived by a person skilled in the art from the embodiments disclosed herein without making any creative effort, shall fall within the protection scope of the present disclosure.
Specific embodiments of the present disclosure are described in detail below with reference to the accompanying drawings.
Referring to fig. 1, fig. 1 is a schematic structural diagram of an embodiment of an underground pressure pipeline leakage detection system provided by the present application. As shown in fig. 1, the underground pressure pipeline leakage detection system 100 of the present embodiment includes at least: the device comprises a pipeline body 11, a sound wave detection probe 12, a signal acquisition card 13 and a computer acquisition terminal 14.
The pipeline body 11 can be an experimental pipeline installed underground, and the acoustic wave detection probe 12 comprises an acoustic emission sensor, is arranged on the pipeline body 11, and is used for acquiring an acoustic wave signal of the pipeline body; the signal acquisition card 13 is connected to the sound wave detection probe 12, and is configured to acquire a sound wave signal acquired by the sound wave detection probe 12.
Further, as shown in fig. 1, the system 100 for detecting leakage of an underground pressure pipe in the present embodiment at least includes two acoustic wave detection probes 12 respectively disposed at two ends of the pipe body 11, wherein the at least two acoustic wave detection probes 12 are respectively connected to a signal acquisition card 13 through a preposed signal amplifying device 15, so as to transmit the acquired acoustic wave signals to the signal acquisition card 13.
Specifically, please continue to refer to fig. 2 for the signal acquisition process of the underground pressure pipeline leakage detection system 100, and fig. 2 is a schematic diagram of the leakage data acquisition process provided herein. Preferably, the acoustic wave detection probe 12 of the present embodiment may employ the acoustic wave sensor 1 to perform signal acquisition, the pre-signal amplification device 15 may employ the PAS pre-amplifier 2, the signal acquisition card 13 may employ the NI data acquisition card 3, and the computer acquisition terminal 14 may employ the labview upper computer 4.
In this embodiment, the functions included and capable of being implemented by the field signal processing upper computer software written by the labview software include but are not limited to:
1) and calling a bottom USB serial port interface, connecting the bottom USB serial port interface with hardware, and acquiring data from the high-speed A/D acquisition card into upper computer software through the USB interface.
(2) And displaying the time domain of the original signal in the upper computer software so as to observe the form of the acquired signal.
(3) And carrying out preliminary filtering processing on the original signal, selecting a wavelet denoising algorithm, transplanting the algorithm to a labview software platform, and storing the signal in real time.
(4) And carrying out spectrum analysis on the signal, analyzing the frequency characteristics of the signal, and displaying the spectrum on an upper computer in real time so as to conveniently judge whether leakage occurs.
(5) An input interface is designed, and the frequency, the storage position, the acquisition form and the like of the acquired signals can be set. And an alarm lamp is arranged, so that real-time software alarm can be performed when leakage occurs.
(6) And performing power spectrum analysis on the filtered and denoised signal, integrating the power spectral density, comparing the power spectral value with a set threshold value to obtain a power spectral value obtained by integration, starting a leakage alarm if the power spectral value exceeds the set threshold value, and judging the leakage amount according to the leakage empirical value.
(7) And performing cross-correlation calculation on the signals acquired by the probes, giving out a cross-correlation calculation result, and positioning the distance between the leakage point and the detection probe.
Fig. 2 further reveals the flow relationship of the acoustic signal in the above-mentioned underground pressure pipe leak detection system 100. Specifically, the acoustic wave sensor 1 is connected with the PAS preamplifier 2 through a signal line from M5-KEY to BNC, the PAS preamplifier 2 is connected with the NI high-speed A/D data acquisition card 3 through a BNC coaxial cable, and the NI high-speed data acquisition card 3 is connected with the upper computer 4 through a USB line.
Continuing to combine with the block diagram of the leakage data acquisition module shown in fig. 3, the acoustic wave sensor 1 of the first acoustic wave detection probe acquires a pressure pipeline leakage signal, converts the leakage acoustic wave signal into an analog electrical signal, and transmits the analog electrical signal to the NI high-speed a/D data acquisition card 3 after being amplified by the first PAS preamplifier 2; and an acoustic wave sensor 4 of the second acoustic wave detection probe collects pressure pipeline leakage signals, converts the leakage acoustic wave signals into analog electric signals, and transmits the analog electric signals to the NI high-speed A/D data acquisition card 3 after the analog electric signals are amplified by a second PAS preamplifier 5. After being converted into digital signals in the A/D module, the digital signals are transmitted to the labview upper computer 6, and a leakage signal identification algorithm 8 and a leakage point positioning algorithm 7 are called for processing.
Specifically, please refer to fig. 4 for a principle of detecting a pipeline leakage by using an acoustic method according to an embodiment of the present disclosure, and fig. 4 is a schematic diagram of detecting a pipeline leakage by using an acoustic method according to the present disclosure. As shown in fig. 4, when a leak occurs, the pressure difference between the inside and outside of the pipe causes the leaked liquid to form a vortex when passing through the crack or leak point, and the vortex generates oscillatory sound waves and pressure fluctuations. The sound waves generated by the leakage generate a sound field, and the detection of the leakage is performed by using a sound pickup sensor. The sound wave is generated and propagated in different ways, and the difference of the ways of spreading can be divided into longitudinal wave existing in the medium and transverse wave existing in the solid of the pipe wall, and surface wave existing on the surface of the solid. Since longitudinal waves, transverse waves, and surface waves in a solid are attenuated greatly, a longitudinal wave existing in a medium is generally detected by an acoustic wave sensor. After the acoustic wave sensor detects longitudinal waves of the acoustic wave diffusion, acoustic wave signals are converted into analog voltage signals. The analog voltage signal is transmitted to a preposed signal amplifying device for amplification. The amplified voltage signal is transmitted to a high-speed A/D acquisition card for signal acquisition and converted into a digital signal, and the digital signal is transmitted to a data processing interrupt through a USB interface for response data processing.
As further described below with respect to the underground pressure pipe leak detection system 100 of fig. 1, the pipe body 11 portion further includes a shock-resistant pressure sensor 16, a throttle valve 17, a variable pressure plunger pump 18, a liquid flow meter 19, and a reservoir 110. It should be noted that the description of the pipe body 11 in this section is only a detailed description of the pipe body 11, and does not limit the protection scope of the underground pressure pipe leakage detection system 100 of the present application.
The constructed underground pressure pipeline leakage detection system 100 of the embodiment can be used for analyzing the characteristics of relevant factors of pipeline leakage and providing reference basis for pipeline construction and reasonable arrangement; in addition, the underground pressure pipeline leakage detection system 100 of the embodiment builds a PC end upper computer system based on labview software, and can realize the functions of local real-time data processing, real-time alarming and positioning.
It should be noted that the components of the underground pressure pipe leakage detection system 100 may be implemented by other reasonable devices, which are not described herein again.
Next, a method for detecting leakage of an underground pressure pipeline according to the present application is specifically described based on the system 100 for detecting leakage of an underground pressure pipeline introduced above, and specifically refer to fig. 5, where fig. 5 is a schematic flow chart of an embodiment of the method for detecting leakage of an underground pressure pipeline according to the present application.
Specifically, the method for detecting the leakage of the underground pressure pipeline comprises the following steps:
step S501: a first acoustic signal of an underground pressure pipe is collected.
Before the official detection, the worker needs to set the underground pressure pipeline leakage detection system 100 in advance. The specific setting process is as follows:
(1) an experimental pipeline and a water supply device shown in figure 1 are built, leakage holes with different leakage hole diameters are formed in the pipeline, and matched plugging wires are matched, so that leakage experiments with different leakage hole diameters can be carried out.
(2) The method comprises the following steps of grinding the place, attached to the sound wave sensor, of the pipe wall of the pipe body with abrasive paper, smearing the couplant special for the ultrasonic detector, attaching the sound wave sensor to the pipe body, and pressing the place, attached to the couplant, of the sound wave sensor and the pipe wall with the special probe clamp. All probes in fig. 1 should be handled in exactly the same manner and fixture.
(3) At least two paths of probes are respectively connected with the corresponding preposed operational amplifiers, the preposed operational amplifiers can amplify sound wave signals collected by the probes in different amplitudes, and the amplification amplitude is adjustable.
(4) At least two prepositive operational amplifiers are connected to a high-speed A/D signal acquisition card.
(5) The high-speed A/D signal acquisition card is connected to a computer data acquisition terminal.
(6) The computer data acquisition terminal consists of a PC and a labview-based data acquisition upper computer running on the PC. And the upper computer acquires the data transmitted from the high-speed A/D signal acquisition card through the binding data receiving serial port.
(7) And drawing a time domain image according to the acquired original data and displaying the time domain image on an upper computer in real time.
Further, the method for detecting the leakage of the underground pressure pipeline in the embodiment can explore the influence effect of the factors on the leakage signal by adjusting the pressure of the booster pump, the size of the leakage aperture and the distance from the probe to the leakage point.
In this step, the detection system collects a first acoustic signal of the underground pressure pipeline through the acoustic detection probe
Step S502: a frequency band in which the leak signal is concentrated is acquired based on the first acoustic wave signal.
The detection system carries out wavelet denoising processing on the collected first sound wave signals and takes out some noise signals of the first sound wave signals. Wavelet signals are widely used due to the superior engineering characteristics of the wavelet signals, and good results can be obtained by processing pipeline leakage signal data through the wavelet signals.
The detection system further performs band-pass filtering processing on the denoised first sound wave signal, and takes out a frequency band in which the leakage signal is concentrated from the first sound wave signal.
Step S503: power spectrum values are obtained based on the frequency bands in the leakage signal set.
The detection system performs power spectral density calculation on the frequency band with concentrated leakage signals, and draws a power spectral density curve. Then, the detection system further performs integration processing on the power spectral density curve to obtain a power spectral value of the leakage signal.
Step S504: and judging whether the power spectrum value is greater than or equal to a preset power spectrum threshold value.
The detection system compares the power spectrum value of the leakage signal with a preset power spectrum threshold value, judges whether leakage occurs or not according to the comparison result and confirms the leakage amount. Specifically, when the power spectrum value of the leakage signal is equal to or greater than the preset power spectrum threshold, the process proceeds to step S505.
Step S505: confirming the leakage of the underground pressure pipeline.
The detection system confirms that the underground pressure pipeline generates leakage, triggers an alarm button in the upper computer and gives out leakage alarm.
Further, the detection system calculates a difference value between the power spectrum value of the leakage signal and a preset power spectrum threshold value, and then calculates the leakage amount generated by the underground pressure pipeline according to the difference value and a preset conversion formula, or refers to a preset difference value-leakage amount table to obtain the leakage amount generated by the underground pressure pipeline.
Besides confirming whether the underground pressure pipeline generates leakage and the leakage amount, the detection system of the embodiment can further position the leakage point on the pipeline body, and the specific steps are as follows:
the first sound wave signal comprises at least two paths of second sound wave signals, and the at least two paths of second sound wave signals are acquired by two or more probes arranged on the underground pressure pipeline respectively. The detection system performs cross-correlation analysis on the at least two paths of second acoustic signals subjected to band-pass filtering and denoising to obtain time delay difference time between the at least two paths of second acoustic signals; and substituting the obtained time delay difference time into a time delay estimation calculation formula to calculate the distance between the leakage point and the two probes.
The method for detecting the leakage of the underground pressure pipeline can quantitatively analyze and collect signals by combining a wavelet denoising method with a power spectral density method; and judging whether leakage occurs or not and the size of the leakage amount by a threshold judgment method. Compared with the prior art, the method has the advantages that the leakage judgment accuracy is improved, the false alarm rate is reduced, and the leakage condition can be preliminarily evaluated. The method for detecting the leakage of the underground pressure pipeline can also perform correlation analysis on the signals collected by the multi-channel probe in a mode of combining wavelet denoising, band-pass filtering and cross-correlation time delay estimation, so as to obtain the time delay difference and position the position of the leakage point, and compared with the prior art, the positioning precision is improved.
Referring to fig. 6, fig. 6 is a schematic diagram of a frame of an embodiment of an electronic device provided in the present application. The electronic device 60 includes a memory 61 and a processor 62 coupled to each other, the processor 62 being configured to execute program instructions stored in the memory 61 to implement the steps of any of the above-described embodiments of the method for leak detection of a subterranean pressure conduit. In one particular implementation scenario, electronic device 60 may include, but is not limited to: a microcomputer, a server, and in addition, the electronic device 60 may also include a mobile device such as a notebook computer, a tablet computer, and the like, which is not limited herein.
In particular, the processor 62 is configured to control itself and the memory 61 to implement the steps in any of the above-described embodiments of the method of underground pressure conduit leak detection. The processor 62 may also be referred to as a CPU (Central Processing Unit). The processor 62 may be an integrated circuit chip having signal processing capabilities. The Processor 62 may also be a general purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other Programmable logic device, discrete Gate or transistor logic, discrete hardware components. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. In addition, the processor 62 may be collectively implemented by an integrated circuit chip.
Referring to fig. 7, fig. 7 is a block diagram illustrating an embodiment of a computer-readable storage medium according to the present application. The computer readable storage medium 70 stores program instructions 701 executable by a processor, the program instructions 701 for implementing steps in any of the above-described embodiments of a method of underground pressure conduit leak detection.
In some embodiments, functions of or modules included in the apparatus provided in the embodiments of the present disclosure may be used to execute the method described in the above method embodiments, and specific implementation thereof may refer to the description of the above method embodiments, and for brevity, will not be described again here.
The foregoing description of the various embodiments is intended to highlight various differences between the embodiments, and the same or similar parts may be referred to each other, and for brevity, will not be described again herein.
In the embodiments provided in the present invention, it should be understood that the disclosed method and apparatus can be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, a division of a module or a unit is merely one type of logical division, and an actual implementation may have another division, for example, a unit or a component may be combined or integrated with another system, or some features may be omitted, or not implemented. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection of devices or units through some interfaces, and may be in an electrical, mechanical or other form.
In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.
The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention may be substantially or partially implemented in the form of a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, a network device, or the like) or a processor (processor) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.
In the above description of the present specification, the terms "fixed," "mounted," "connected," or "connected," and the like, are to be construed broadly unless otherwise expressly specified or limited. For example, with the term "coupled", it can be fixedly coupled, detachably coupled, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship. Therefore, unless the specification explicitly defines otherwise, those skilled in the art can understand the specific meaning of the above terms in the present invention according to specific situations.
From the above description of the present specification, those skilled in the art will also understand the terms used below, terms indicating orientation or positional relationship such as "upper", "lower", "front", "rear", "left", "right", "length", "width", "thickness", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", "central", "longitudinal", "transverse", "clockwise" or "counterclockwise" and the like are based on the orientation or positional relationship shown in the drawings of the present specification, it is for the purpose of facilitating the explanation of the invention and simplifying the description, and it is not intended to state or imply that the devices or elements involved must be in the particular orientation described, constructed and operated, therefore, the above terms of orientation or positional relationship should not be construed or interpreted as limiting the present invention.
In addition, the terms "first" or "second", etc. used in this specification are used to refer to numbers or ordinal terms for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the feature. In the description of the present specification, "a plurality" means at least two, for example, two, three or more, and the like, unless specifically defined otherwise.
While various embodiments of the present invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous modifications, changes, and substitutions will occur to those skilled in the art without departing from the spirit and scope of the present invention. It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the invention and that the module compositions, equivalents, or alternatives falling within the scope of these claims be covered thereby.