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CN-122016166-A - Leakage position detection method and device based on physical nuclear magnetic detection

CN122016166ACN 122016166 ACN122016166 ACN 122016166ACN-122016166-A

Abstract

The invention discloses a leakage position detection device based on physical nuclear magnetic detection, which comprises a transmitting coil, a receiving coil, a signal processing unit, a control unit and a display unit, wherein the transmitting coil is used for transmitting radio frequency pulses to a detected object to generate a radio frequency magnetic field for exciting atomic nuclei to generate magnetic resonance, the receiving coil is used for collecting magnetic resonance signals generated by the atomic nuclei, the signal processing unit is electrically connected with the receiving coil and is used for amplifying, filtering and digitizing the magnetic resonance signals, the control unit is respectively electrically connected with the transmitting coil and the signal processing unit and is used for controlling parameters of the radio frequency pulses according to a preset pulse sequence and coordinating sampling time sequences of the signal processing unit, and the display unit is in communication connection with the control unit and is used for outputting leakage detection results. By introducing a physical nuclear magnetic detection technology and utilizing the characteristic magnetic resonance relaxation time of leaked substances, the centimeter-level high-precision positioning is realized, and the interference of environmental noise and temperature and humidity is effectively avoided.

Inventors

  • Diao shu
  • HUANG WEIMING
  • CAO XIAOBING
  • ZHOU GUANGHONG
  • HE JIAWEI

Assignees

  • 无锡职业技术大学

Dates

Publication Date
20260512
Application Date
20260129

Claims (10)

  1. 1. A leakage position detection device based on physical nuclear magnetic detection, comprising: a transmitting coil (1) for transmitting a radio frequency pulse to a detected object to generate a radio frequency magnetic field for exciting nuclei to generate magnetic resonance; A receiving coil (2) for acquiring magnetic resonance signals generated by the nuclei; the signal processing unit (4) is electrically connected with the receiving coil (2) and is used for amplifying, filtering and digitizing the magnetic resonance signals; The control unit (3) is respectively and electrically connected with the transmitting coil and the signal processing unit, and is used for controlling parameters of the radio frequency pulse according to a preset pulse sequence and coordinating sampling time sequences of the signal processing unit (4); And the display unit (5) is in communication connection with the control unit (3) and is used for outputting a leakage detection result.
  2. 2. The leakage position detection device based on physical nuclear magnetic detection according to claim 1, wherein the receiving coil (2) is an array structure formed by a plurality of receiving coils (2), and the control unit (3) determines coordinates of the leakage position by performing spatial correlation analysis on signal intensities received by each sub-coil in the array structure.
  3. 3. The leakage position detection device based on physical nuclear magnetic detection according to claim 1, characterized in that the signal processing unit (4) comprises a feature extraction module for calculating a longitudinal relaxation time T1 and a transversal relaxation time T2 of the magnetic resonance signal.
  4. 4. The leakage position detection device based on physical nuclear magnetic detection according to claim 1, wherein the transmitting coil (1) and the receiving coil (2) are connected to the signal processing unit (4) through a coaxial cable, and the control unit (3) and the display unit (5) are connected through a wireless communication module.
  5. 5. A leakage location detection method based on physical nuclear magnetic detection, characterized in that the device according to any one of claims 1-4 is applied, comprising the steps of: S1, setting the frequency, amplitude and pulse width of a radio frequency pulse through a control unit (3), and driving a transmitting coil (1) to apply a radio frequency magnetic field to a detected area; s2, acquiring a free induction attenuation signal generated by energy released by excited atomic nuclei by using a receiving coil (2), and transmitting the signal to the signal processing unit (4); S3, performing digital processing on the free induction attenuation signal through a signal processing unit (4) to extract signal intensity characteristics and relaxation time characteristics; s4, comparing a preset substance parameter library through a data analysis algorithm, identifying the type of the leaked substance according to the relaxation time characteristics, and determining the leakage position according to the space distribution inversion of the signal intensity characteristics.
  6. 6. The method for detecting a leak location based on physical nuclear magnetic resonance detection according to claim 5, wherein in the step of determining a leak location by inversion, a central projection coordinate of a leak region is located by calculating an amplitude gradient of each channel signal in the receiving coil array in combination with an electromagnetic field attenuation model.
  7. 7. The method for detecting a leakage position based on physical nuclear magnetic resonance detection according to claim 5, wherein the substance parameter library stores standard relaxation time ranges of different mediums under specific magnetic field intensity, and the leakage substance is distinguished as water or oil by matching the relaxation time characteristics extracted in real time with the standard relaxation time ranges.
  8. 8. The method for detecting a leak location based on physical nuclear magnetic resonance detection according to claim 5, further comprising: Before the step S1, the static magnetic field intensity is preset by the control unit (3) according to the material of the detected object, and the static magnetic field is generated by an external permanent magnet or an electromagnet and is used for leading atomic nuclei in the detected object to precess.
  9. 9. The method for detecting a leakage position based on physical nuclear magnetic resonance detection according to claim 5, wherein the step S3 further comprises: And performing time-frequency transformation on the digitized signals through a signal processing unit (4), extracting frequency domain characteristics, and performing multi-characteristic fusion analysis by combining the relaxation time characteristics.
  10. 10. The method for detecting a leak location based on physical nuclear magnetic detection of claim 5, further comprising: At least one of a signal intensity profile, a relaxation time profile and a three-dimensional coordinate of the leak location is displayed in real time by the display unit (5).

Description

Leakage position detection method and device based on physical nuclear magnetic detection Technical Field The invention relates to the technical field of physical detection and inspection, in particular to a leakage position detection method and device based on physical nuclear magnetic detection. Background In the fields of modern basic facilities and industrial production, such as building structures, hydraulic engineering and industrial pipe networks, early detection and accurate positioning of leakage problems are important to guaranteeing facility safety. At present, common leakage detection means mainly comprise manual inspection, pressure test, acoustic detection and infrared thermal imaging detection. However, the technology has obvious limitations in practical application, such as low manual inspection efficiency, difficulty in finding hidden leakage, complex pressure test operation, easiness in secondary damage to a pipeline system and insufficient sensitivity to tiny leakage, easiness in acoustic detection, difficulty in signal identification caused by interference of urban or industrial environmental noise, high dependence on temperature difference between leakage substances and surrounding environment in infrared thermal imaging detection, and great reduction in detection accuracy when the temperature difference is not obvious or the environmental temperature and humidity fluctuate in a large range. Disclosure of Invention The invention aims to provide a leakage position detection method and device based on physical nuclear magnetic detection, which are used for solving the problem that the detection accuracy of the existing leakage detection means is not high. In order to solve the above problems, the present invention discloses a leakage position detection device based on physical nuclear magnetic detection, comprising: a transmitting coil for transmitting a radio frequency pulse to the object to be detected to generate a radio frequency magnetic field that excites nuclei to generate magnetic resonance; A receiving coil for collecting magnetic resonance signals generated by the atomic nuclei; The signal processing unit is electrically connected with the receiving coil and is used for amplifying, filtering and digitizing the magnetic resonance signals; The control unit is respectively and electrically connected with the transmitting coil and the signal processing unit, and is used for controlling the parameters of the radio frequency pulse according to a preset pulse sequence and coordinating the sampling time sequence of the signal processing unit; and the display unit is in communication connection with the control unit and is used for outputting a leakage detection result. Preferably, the receiving coil is an array structure formed by a plurality of receiving coils, and the control unit determines the coordinates of the leakage position by performing spatial correlation analysis on the signal intensity received by each sub-coil in the array structure. Preferably, the signal processing unit comprises a feature extraction module for calculating a longitudinal relaxation time T1 and a transversal relaxation time T2 of the magnetic resonance signals. Preferably, the transmitting coil and the receiving coil are connected to the signal processing unit through coaxial cables, and the control unit and the display unit are connected through a wireless communication module. The invention also discloses a leakage position detection method based on physical nuclear magnetic detection, which comprises the following steps: s1, setting the frequency, amplitude and pulse width of a radio frequency pulse through a control unit, and driving a transmitting coil to apply a radio frequency magnetic field to a detected area, wherein before step S1, the static magnetic field strength is preset according to the material of the detected object through the control unit, and the static magnetic field is generated by an external permanent magnet or an electromagnet and is used for enabling atomic nuclei in the detected object to precess. S2, acquiring a free induction attenuation signal generated by energy released by excited atomic nuclei by using a receiving coil, and transmitting the signal to the signal processing unit; S3, performing digital processing on the free induction attenuation signal through a signal processing unit to extract signal intensity characteristics and relaxation time characteristics, performing time-frequency transformation on the digitized signal through the signal processing unit to extract frequency domain characteristics, and performing multi-characteristic fusion analysis by combining the relaxation time characteristics so as to improve accuracy of identifying leakage substance types. S4, comparing a preset substance parameter library through a data analysis algorithm, storing standard relaxation time ranges of different mediums under specific magnetic field intensity in the substance pa