A method and system for intelligent diagnosis and leak location of vacuum degree in vacuum heat exchangers

Abstract

This invention belongs to the field of industrial equipment condition monitoring and fault diagnosis technology, specifically a method and system for intelligent diagnosis and leak location of vacuum degree in a vacuum heat exchanger. It includes a heat exchanger shell, a data acquisition layer, an intelligent analysis layer, and an execution feedback layer. The data acquisition layer is used to collect absolute pressure signals, temperature distribution signals, and acoustic vibration signals. The intelligent analysis layer is used to run prediction models, diagnostic algorithms, and location algorithms. The execution feedback layer is used to perform maintenance compensation and alarm functions. The heat exchanger shell is equipped with a set of flange seats. Feedthrough flanges are connected to the flange seats. Sensing elements are fixedly connected to the feedthrough flanges. By integrating a sensor array and combining the prediction model, diagnostic algorithm, and location algorithm of the intelligent analysis layer, online real-time monitoring and intelligent diagnosis of the heat exchanger vacuum degree can be achieved. Accurate early warnings of minor leaks can be provided without equipment shutdown, distinguishing between normal pressure fluctuations and abnormal leaks.

Description

Technical Field

[0001] This invention belongs to the field of industrial equipment condition monitoring and fault diagnosis technology, specifically a method and system for intelligent diagnosis of vacuum degree and leakage location of vacuum heat exchanger. Background Technology

[0002] Vacuum heat exchangers achieve superior heat transfer efficiency by establishing and maintaining a high vacuum environment within them. This efficient heat transfer mechanism fundamentally relies on the stability of the vacuum state. Therefore, the long-term stability and reliability of the vacuum level are the most critical factors ensuring the continuous and efficient operation of the entire heat exchanger system. In actual operation, the vacuum level is not constant; its degradation often stems from extremely small leaks within the equipment or at connection points, which are difficult to detect by conventional means. Although the initial impact of such leaks is weak and difficult to detect, it triggers a slow and continuous gas infiltration process, gradually disrupting the vacuum environment and causing a gradual and imperceptible decline in heat transfer performance. Therefore, close monitoring of the vacuum level and prevention of even minor leaks are crucial for maintaining the long-term performance of the equipment.

[0003] Traditional maintenance relies primarily on periodic offline leak detection (such as pressure testing and helium mass spectrometry leak detection), which suffers from problems such as requiring equipment shutdown, lack of early warning, and low efficiency in leak location. While existing technologies include solutions that use a single pressure sensor to set a threshold for alarms, these cannot distinguish between normal pressure fluctuations and early, slow leaks, resulting in a high false alarm rate and a complete lack of leak location capability. Therefore, there is an urgent need for a technical solution capable of online, real-time, and intelligent diagnosis of vacuum anomalies and rapid leak location.

[0004] Therefore, the present invention provides a method and system for intelligent diagnosis and leakage location of vacuum degree in vacuum heat exchangers. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, at least one technical problem raised in the background art is solved.

[0006] The technical solution adopted by the present invention to solve its technical problem is: the intelligent diagnosis and leakage location system for vacuum degree of vacuum heat exchanger described in the present invention includes heat exchanger shell, data acquisition layer, intelligent analysis layer and execution feedback layer;

[0007] The data acquisition layer includes an absolute pressure sensor, a temperature sensor array, and an acoustic sensor array disposed on the inner wall of the heat exchanger shell, for acquiring absolute pressure signals, temperature distribution signals, and acoustic vibration signals.

[0008] The intelligent analysis layer is connected to the data acquisition layer and is used to run prediction models, diagnostic algorithms, and localization algorithms.

[0009] The execution feedback layer is connected to the intelligent analysis layer and includes a vacuum maintaining pump, an audible and visual alarm, and a human-machine interface, used to perform maintenance compensation and alarm operations.

[0010] A set of flange seats are arrayed on the surface of the heat exchanger shell; a data acquisition channel is provided inside the flange seat; a feedthrough flange is connected to the end of the flange seat; a sensing element is fixedly connected to the side of the feedthrough flange near the data acquisition channel; the sensing element includes an absolute pressure sensor, a temperature sensor or an acoustic sensor, and the cable of the sensing element extends outward through the feedthrough flange.

[0011] Preferably, a boss is provided on the top of the flange seat; a switching groove is provided inside the boss and the flange seat; a switching plate is slidably connected inside the switching groove; an electric telescopic rod is fixedly connected to the surface of the heat exchanger shell above the boss; the output rod of the electric telescopic rod is fixedly connected to the switching plate, and the output rod is slidably sealed to the top of the boss.

[0012] Preferably, annular grooves are provided on both sides of the switching plate; an elastic annular pad is fixedly connected inside the annular groove.

[0013] Preferably, an elastic stop is fixedly connected to the lower side of the switching plate; both the stop and the annular pad are designed as hollow structures and are interconnected through pipelines.

[0014] Preferably, a porous water-absorbing block is fixedly connected to the bottom of the switching plate near the sensing element.

[0015] Preferably, a water-squeezing plate is hinged to the top of the collection channel; a tension spring is fixedly connected between the water-squeezing plate and the collection channel; a magnetic block is fixedly connected to the bottom of the water-squeezing plate; a permanent magnet is fixedly connected to the bottom of the switching plate; the permanent magnet and the magnetic block attract each other when they are close together.

[0016] Preferably, a set of elastic protrusions are evenly distributed on the surface of the porous absorbent block; a set of elastic spikes are evenly distributed on the side of the squeezing plate near the switching plate.

[0017] Preferably, a return pipe is connected between the bottom of the switching slot and the heat exchanger shell.

[0018] A method for intelligent diagnosis and leak location of vacuum degree in a vacuum heat exchanger, the method employing the aforementioned intelligent diagnosis and leak location system, includes the following steps:

[0019] S1. Data Synchronous Acquisition: Absolute pressure signal, temperature distribution signal and acoustic vibration signal are synchronously acquired through a sensor array integrated on the inner wall of the vacuum heat exchanger.

[0020] S2. Dynamic baseline prediction and comparison: Based on the historical normal operation data of the equipment, a dynamic baseline prediction model for the normal decay of vacuum degree is established through a machine learning model, and the real-time collected vacuum degree data is compared with the dynamic baseline prediction value in real time.

[0021] S3. Abnormal mode diagnosis: Analyze the comparison results. If the actual vacuum decay rate continues and deviates significantly from the predicted baseline, it is determined that the vacuum system has an abnormal leakage mode.

[0022] S4. Leakage Area Location: When an abnormal leak is detected, the acoustic sensor array is activated, and a location algorithm based on Time Difference of Arrival (TDOA) is used to calculate the spatial location of the leak source.

[0023] S5. Hierarchical Decision-Making and Response: Determine the leakage level based on the decay rate of the abnormal leakage, and execute corresponding automatic maintenance compensation or alarm operations according to different levels.

[0024] The beneficial effects of this invention are as follows:

[0025] 1. The present invention discloses an intelligent diagnostic and leak location method and system for vacuum heat exchanger vacuum degree. By integrating an absolute pressure sensor, a temperature sensor array, and an acoustic sensor array, and combining the predictive model, diagnostic algorithm, and location algorithm of the intelligent analysis layer, the present invention achieves online real-time monitoring and intelligent diagnosis of vacuum heat exchanger vacuum degree. It can accurately warn of early minor leaks without equipment shutdown, effectively distinguish between normal pressure fluctuations and abnormal leaks, significantly reduce false alarm rate, and transform the traditional passive and offline maintenance mode into predictive maintenance. At the same time, the acoustic sensor array and location algorithm can quickly locate the leak area, overcome the shortcomings of low location efficiency of traditional leak detection methods, and significantly improve the operational reliability and maintenance efficiency of the equipment.

[0026] 2. The intelligent diagnosis and leak location method and system for vacuum degree of a vacuum heat exchanger described in this invention, when the sensing element needs to be repaired or replaced, drives its output rod downward by an electric telescopic rod, causing the switching plate to slide downward along the switching groove until the switching plate completely blocks the acquisition channel. At this time, the annular gaskets on both sides can seal the gap between the switching plate and the switching groove. The external environment is isolated from the vacuum chamber of the heat exchanger by the switching plate, ensuring that the sealing performance of the vacuum chamber is not affected during the repair or replacement of the sensing element, avoiding equipment shutdown due to loss of vacuum in the chamber, realizing rapid maintenance of the sensing element without stopping the machine, and improving the continuous operation capability and maintenance convenience of the equipment. Attached Figure Description

[0027] The invention will now be further described with reference to the accompanying drawings.

[0028] Figure 1This is a schematic diagram of the intelligent diagnosis and leak location system in this invention;

[0029] Figure 2 This is a schematic diagram of the flange seat in this invention;

[0030] Figure 3 This is a schematic diagram of the internal structure of the flange seat in this invention;

[0031] Figure 4 This is a schematic diagram of the switching plate in this invention;

[0032] Figure 5 This is a sectional view of the flange seat in this invention;

[0033] Figure 6 yes Figure 5 Enlarged view of a portion of point A in the middle;

[0034] Figure 7 yes Figure 5 Enlarged view of a section at point B in the middle;

[0035] Figure 8 This is the overall flowchart of the intelligent diagnosis and leak location method in this invention;

[0036] Figure 9 This is a detailed flowchart of the algorithm for leak localization based on acoustic sensor arrays and the time difference of arrival principle in this invention;

[0037] Figure 10 This is a flowchart of the intelligent diagnosis and decision-making process in this invention.

[0038] In the diagram: 1. Heat exchanger shell; 2. Flange seat; 3. Acquisition channel; 4. Feedthrough flange; 5. Sensing element; 6. Boss; 7. Switching groove; 8. Switching plate; 9. Electric telescopic rod; 10. Annular groove; 11. Annular gasket; 12. Stop block; 13. Porous water suction block; 14. Water squeezing plate; 15. Tension spring; 16. Magnetic block; 17. Permanent magnet; 18. Elastic protrusion; 19. Elastic spike; 20. Return pipe. Detailed Implementation

[0039] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0040] like Figures 1 to 7 As shown, the intelligent diagnosis and leak location system for vacuum degree of vacuum heat exchanger of the present invention includes heat exchanger shell 1, data acquisition layer, intelligent analysis layer and execution feedback layer.

[0041] The data acquisition layer includes an absolute pressure sensor, a temperature sensor array, and an acoustic sensor array disposed on the inner wall of the heat exchanger housing 1, for acquiring absolute pressure signals, temperature distribution signals, and acoustic vibration signals.

[0042] The intelligent analysis layer is connected to the data acquisition layer and is used to run prediction models, diagnostic algorithms and localization algorithms. Functionally, it includes a prediction module, a diagnostic module and a localization module.

[0043] The execution feedback layer is connected to the intelligent analysis layer and includes a vacuum maintaining pump, an audible and visual alarm, and a human-machine interface, used to perform maintenance compensation and alarm operations.

[0044] A set of flange seats 2 are arrayed on the surface of the heat exchanger shell 1; the flange seat 2 is provided with a data acquisition channel 3, and the data acquisition channel 3 communicates with the interior of the heat exchanger shell 1; a feedthrough flange 4 is fixedly connected to the end of the flange seat 2 by bolts; a sensing element 5 is fixedly connected to the side of the feedthrough flange 4 near the data acquisition channel 3; the sensing element 5 can be an absolute pressure sensor, a temperature sensor or an acoustic sensor, and the cable of the sensing element 5 extends outward through the feedthrough flange 4.

[0045] This invention employs flange seats 2 arrayed on the surface of the heat exchanger shell 1. The flange seats 2 house sensing elements 5, such as absolute pressure sensors, temperature sensors, or acoustic sensors, and these sensing elements 5 are connected to the interior of the shell via a data acquisition channel 3. Each sensing element 5 acquires absolute pressure signals, temperature distribution signals, and acoustic vibration signals from within the shell in real time. Cables are led out through a feedthrough flange 4 for airtightness. After receiving these signals, the intelligent analysis layer runs a prediction model, diagnostic algorithm, and positioning algorithm to dynamically assess the vacuum status and identify anomalies. When a vacuum anomaly or leak is detected, the intelligent analysis layer sends a command to the execution feedback layer to control the vacuum maintaining pump for automatic compensation, or triggers an audible and visual alarm and displays alarm information and positioning results on the human-machine interface.

[0046] This invention achieves modular and detachable fixing of sensors by arraying flange seats 2 on the shell surface and installing sensing elements 5 in conjunction with feedthrough flanges 4. This facilitates flexible configuration of different types of sensors such as absolute pressure, temperature, or acoustic sensors according to actual needs, reducing installation and maintenance difficulty. At the same time, the cable extends outward through the feedthrough flanges 4, ensuring the sealing reliability of the vacuum cavity. Combined with the intelligent analysis layer and the execution feedback layer, the system can monitor changes in vacuum level in real time, automatically identify abnormal leaks, and perform graded compensation or alarms, significantly improving the intelligence level and maintenance efficiency of vacuum heat exchanger operation.

[0047] This invention integrates an absolute pressure sensor, a temperature sensor array, and an acoustic sensor array, combined with a predictive model, diagnostic algorithm, and localization algorithm in an intelligent analysis layer, to achieve online real-time monitoring and intelligent diagnosis of vacuum levels in vacuum heat exchangers. It can accurately warn of early minor leaks without shutting down the equipment, effectively distinguishing between normal pressure fluctuations and abnormal leaks, significantly reducing false alarm rates, and transforming the traditional passive, offline maintenance mode into predictive maintenance. At the same time, the acoustic sensor array and localization algorithm can quickly locate the leak area, overcoming the low localization efficiency of traditional leak detection methods, and significantly improving the operational reliability and maintenance efficiency of the equipment.

[0048] In one embodiment of the present invention, a boss 6 is provided on the top of the flange seat 2; a switching groove 7 is provided inside the boss 6 and the flange seat 2, and the switching groove 7 is connected to the collection channel 3; a switching plate 8 is slidably connected inside the switching groove 7; an electric telescopic rod 9 is fixedly connected to the surface of the heat exchanger shell 1 above the boss 6; the output rod of the electric telescopic rod 9 is fixedly connected to the switching plate 8, and the output rod is slidably sealed to the top of the boss 6.

[0049] Both sides of the switching plate 8 are provided with annular grooves 10; an elastic annular pad 11 is fixedly connected inside the annular groove 10.

[0050] Under normal circumstances, the electric telescopic rod 9 is in the retracted state, and the switching plate 8 is located at the top, which will not obstruct the signal acquisition of the sensing element 5. When the sensing element 5 needs to be repaired or replaced, the output rod of the electric telescopic rod 9 is driven to extend downward, causing the switching plate 8 to slide down along the switching groove 7 until the switching plate 8 completely blocks the acquisition channel 3. At this time, the annular gaskets 11 on both sides can seal the gap between the switching plate 8 and the switching groove 7. The external environment and the vacuum chamber of the heat exchanger are isolated by the switching plate 8, ensuring that the sealing of the vacuum chamber is not affected during the repair or replacement of the sensing element 5, avoiding equipment shutdown due to loss of vacuum in the chamber, realizing rapid maintenance of the sensing element 5 without stopping the machine, and improving the continuous operation capability and maintenance convenience of the equipment. After the repair or replacement is completed, the sensing element 5 and the feedthrough flange 4 are reinstalled, the electric telescopic rod 9 is controlled to retract, the switching plate 8 is raised to the initial position, the acquisition channel 3 is reopened, and the sensing element 5 resumes normal signal acquisition.

[0051] Furthermore, when various sensors detect extreme conditions inside the vacuum heat exchanger shell 1, the intelligent analysis layer can control the electric telescopic rod 9 to move the switching plate 8 downward, isolating the sensing element 5 from the internal environment of the heat exchanger. This provides active protection for the sensing element 5, preventing it from being damaged by the extreme environment inside the shell. For example, when a sudden situation such as a pipe rupture causes a high-temperature medium leak inside the heat exchanger, and the temperature sensor detects that the cavity temperature rises sharply to above the tolerance threshold of the sensing element 5 in a short period of time, the switching plate 8 will quickly move downward to form a physical barrier, preventing the sensing element 5 from being directly exposed to the high-temperature environment. If the pressure sensor detects an abnormal surge in pressure inside the shell that exceeds the safe range, the switching plate 8 will also promptly cut off the acquisition channel 3 to prevent the high pressure from impacting the sensing element 5.

[0052] In one embodiment of the present invention, an elastic stop 12 is fixedly connected to the lower side of the switching plate 8; the stop 12 and the annular pad 11 are both designed as hollow structures and are interconnected by pipelines.

[0053] Under normal conditions, the annular pad 11 is recessed inside the annular groove 10, preventing the annular pad 11 from contacting or rubbing against the inner wall of the switching groove 7 during the up-and-down movement of the switching plate 8, thus preventing the annular pad 11 from wearing out. Only when the switching plate 8 moves to the bottom, the stop block 12 is squeezed by the bottom of the switching groove 7, and the gas or liquid inside it is forced into the annular pad 11, causing the annular pad 11 to bulge out from the annular groove 10 and fit tightly against the inner wall of the switching groove 7, forming an effective sealing structure. This completely isolates the acquisition channel 3 where the sensing element 5 is located from the inside of the vacuum heat exchanger housing 1, ensuring that the sealing of the cavity is not affected under extreme conditions or during maintenance, and preventing the vacuum environment from being damaged. This structure not only ensures the smooth movement of the switching plate 8 during normal operation, reduces the wear of the annular pad 11, and extends its service life, but also plays a role quickly when sealing is required, achieving a reliable isolation effect.

[0054] In one embodiment of the present invention, a porous water-absorbing block 13 is fixedly connected to the bottom of the switching plate 8 near the sensing element 5.

[0055] The absorbent block is made of highly absorbent resin material with interconnected micropores inside, which can quickly absorb any residual condensation or trace amounts of liquid on the surface of the sensing element 5. When the switching plate 8 moves inside the switching slot 7, the porous absorbent block 13 will come into contact with the sensitive detection area of ​​the sensing element 5. Through its capillary adsorption, it will quickly absorb the water adhering to the surface of the sensing element 5, avoiding the interference of residual water on the accuracy of subsequent measurements. At the same time, the wiping action of the porous absorbent block 13 can also remove any dirt that may adhere to the surface of the sensing element 5, preventing the accumulation of dirt from affecting the reception and conversion of signals by the sensing element 5.

[0056] In order to achieve high-quality cleaning of the surface of the sensing element 5, the switching plate 8 can be periodically controlled by the electric telescopic block to move up and down slightly inside the switching slot 7. That is, the switching plate 8 will not move to the bottom of the switching slot 7 to squeeze the stop block 12, but only control the porous water absorption block 13 to wipe the surface of the sensing element 5 back and forth to achieve a better cleaning effect, realize the periodic cleaning of moisture or dirt on the surface of the sensing element 5, and maintain its working condition.

[0057] In one embodiment of the present invention, a water-squeezing plate 14 is hinged to the top of the collection channel 3; a tension spring 15 is fixedly connected between the water-squeezing plate 14 and the collection channel 3; a magnetic block 16 is fixedly connected to the bottom of the water-squeezing plate 14; a permanent magnet 17 is fixedly connected to the bottom of the switching plate 8; the permanent magnet 17 and the magnetic block 16 attract each other when they are close together.

[0058] When the porous water-absorbing block 13 moves upward with the switching plate 8 to the position of the squeezing plate 14 near the top of the acquisition channel 3, the permanent magnet 17 at the bottom of the switching plate 8 attracts the magnetic block 16 at the bottom of the squeezing plate 14, causing the squeezing plate 14 to deflect towards the switching plate 8 and squeeze the porous water-absorbing block 13. The water adsorbed inside the porous water-absorbing block 13 is squeezed out, and at the same time, the dirt attached to the surface and inside of the porous water-absorbing block 13 is also squeezed out along with the water, effectively ensuring that the porous water-absorbing block 13 can maintain a good dry state and decontamination ability, thereby cleaning the surface of the sensing element 5 in a long-term and stable manner.

[0059] The porous absorbent block 13 has a set of elastic protrusions 18 evenly distributed on its surface; the squeezing plate 14 has a set of elastic spikes 19 evenly distributed on the side near the switching plate 8.

[0060] By setting the elastic protrusions 18, the porous absorbent block 13 can enhance its ability to grasp stubborn dirt when wiping the surface of the sensing element 5. When the porous absorbent block 13 moves upward with the switching plate 8 to the squeezing plate 14, the elastic protrusions 18 of the porous absorbent block 13 and the elastic spikes 19 of the squeezing plate 14 rub and squeeze each other, causing the porous absorbent block 13 to partially peristalse and twist. As the porous absorbent block 13 continues to move upward, the elastic protrusions 18 and the elastic spikes 19 separate from each other, and the porous absorbent block 13 partially rebounds and recovers, forming an intermittent damping-release effect, which causes the fiber structure of the porous absorbent block 13 to vibrate slightly, further promoting the loosening and discharge of deep dirt inside the porous absorbent block 13.

[0061] In one embodiment of the present invention, a return pipe 20 is connected between the bottom of the switching slot 7 and the heat exchanger housing 1.

[0062] The reflux pipe 20 provides an effective discharge path for the squeezed-out water and dirt, so that the water squeezed out from the porous water suction block 13 can flow back to the interior of the heat exchanger shell 1 or the designated collection area through the reflux pipe 20 after falling into the switching tank 7.

[0063] like Figures 8 to 10 As shown, the present invention provides an intelligent diagnosis and leak location method for vacuum degree of a vacuum heat exchanger. This method employs the aforementioned intelligent diagnosis and leak location system and includes the following steps:

[0064] S1. Data Synchronization Acquisition:

[0065] During the manufacturing or modification phase of the vacuum heat exchanger, absolute pressure sensors, temperature sensor arrays (typically arranged on critical heat exchange surfaces), and acoustic sensor arrays (arranged in a regular matrix on the inner wall of the shell) are pre-integrated and installed on the inner wall of the vacuum heat exchanger shell. During equipment operation, all sensors operate continuously, and their signal and power cables are leak-free and led out through feedthrough flanges to the intelligent analysis layer.

[0066] S2. Dynamic baseline prediction and comparison:

[0067] After the system is put into operation, a baseline learning process lasting several weeks is first conducted. The prediction module of the intelligent analysis layer collects historical data under various steady-state operating conditions during this period, trains it using a Long Short-Term Memory (LSTM) network algorithm, and generates a dynamic baseline model that can predict the normal range of vacuum variation based on parameters such as current operating load and temperature. In subsequent real-time monitoring, this model continuously outputs predicted values ​​and compares them at high speed with the actual pressure values ​​collected in step S1.

[0068] S3, Abnormal Pattern Diagnosis:

[0069] The diagnostic module of the intelligent analysis layer is responsible for analyzing and comparing the results. Instead of using a single fixed threshold, it sets a dynamic tolerance range based on statistics. For example, when the actual vacuum level value continuously exceeds the predicted baseline by more than 20%, and this trend persists for more than 10 minutes, the module determines that the system has entered an abnormal leakage mode, and this determination triggers the subsequent localization process.

[0070] S4. Leakage area location:

[0071] Once the diagnostic module confirms the anomaly, the location module immediately activates. It controls the acoustic sensor array to enter a high sampling rate mode, acquiring broadband acoustic / vibration signals generated by the leak. The location module first filters and enhances the signals, then uses the generalized cross-correlation (GCC) algorithm to accurately calculate the time difference of arrival (TDOA) of the same leak signal received by different sensors. Subsequently, with each pair of sensors as the focal point, a set of hyperbolic equations is constructed based on the TDOA and the speed of sound. By solving the intersection region of these hyperbolas (e.g., using Chan's algorithm or Taylor series expansion), the estimated location area of ​​the leak source on the equipment surface can be calculated, and a confidence assessment can be provided.

[0072] S5. Hierarchical Decision-Making and Response:

[0073] The system makes decisions based on the real-time decay rate calculated in step S3. If a minor leak is detected (e.g., the rate is below the set threshold A), a command is sent to the execution feedback layer to automatically start the vacuum maintaining pump for intermittent gas replenishment to maintain the system vacuum level, while displaying a "Compensation in progress" message on the human-machine interface. If a serious leak is detected (e.g., the rate is above the set threshold B), an audible and visual alarm is immediately triggered to issue an emergency alarm, and the location area calculated in step S4 is precisely displayed in a highlighted graphic on the equipment structure diagram on the human-machine interface, and a work order containing suggested maintenance measures is generated.

[0074] The terms "front," "back," "left," "right," "top," and "bottom" all refer to the figures in the accompanying drawings. Figure 1 Based on the perspective of the observer, the side of the device facing the observer is defined as the front, the left side of the observer is defined as the left, and so on.

[0075] In the description of this invention, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

[0076] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. An intelligent diagnostic and leak location system for vacuum degree of a vacuum heat exchanger, characterized in that: It includes the heat exchanger shell (1), the data acquisition layer, the intelligent analysis layer, and the execution feedback layer; The data acquisition layer includes an absolute pressure sensor, a temperature sensor array, and an acoustic sensor array disposed on the inner wall of the heat exchanger shell (1) for acquiring absolute pressure signals, temperature distribution signals, and acoustic vibration signals; The intelligent analysis layer is connected to the data acquisition layer and is used to run prediction models, diagnostic algorithms, and localization algorithms. The execution feedback layer is connected to the intelligent analysis layer and includes a vacuum maintaining pump, an audible and visual alarm, and a human-machine interface, used to perform maintenance compensation and alarm operations. A set of flange seats (2) are arrayed on the surface of the heat exchanger shell (1); a data acquisition channel (3) is provided inside the flange seat (2); a feedthrough flange (4) is connected to the end of the flange seat (2); a sensing element (5) is fixedly connected to the side of the feedthrough flange (4) near the data acquisition channel (3).

2. The intelligent diagnosis and leak location system for vacuum degree of a vacuum heat exchanger according to claim 1, characterized in that: The flange seat (2) is provided with a boss (6) on the top; a switching groove (7) is provided inside the boss (6) and the flange seat (2); a switching plate (8) is slidably connected inside the switching groove (7); an electric telescopic rod (9) is fixedly connected to the surface of the heat exchanger shell (1) above the boss (6); the output rod of the electric telescopic rod (9) is fixedly connected to the switching plate (8), and the output rod is slidably sealed to the top of the boss (6).

3. The intelligent diagnosis and leak location system for vacuum degree of a vacuum heat exchanger according to claim 2, characterized in that: The switching plate (8) has annular grooves (10) on both sides; an elastic annular pad (11) is fixedly connected inside the annular groove (10).

4. The intelligent diagnosis and leak location system for vacuum degree of a vacuum heat exchanger according to claim 3, characterized in that: The switching plate (8) is fixedly connected to a flexible stop (12) on its lower side; the stop (12) and the annular pad (11) are both designed as hollow structures and are connected to each other through pipelines.

5. The intelligent diagnosis and leak location system for vacuum degree of a vacuum heat exchanger according to claim 2, characterized in that: A porous water-absorbing block (13) is fixedly connected to the bottom of the switching plate (8) near the sensing element (5).

6. The intelligent diagnosis and leak location system for vacuum degree of a vacuum heat exchanger according to claim 5, characterized in that: The top of the collection channel (3) is hinged with a water-squeezing plate (14); a tension spring (15) is fixedly connected between the water-squeezing plate (14) and the collection channel (3); a magnetic block (16) is fixedly connected to the bottom of the water-squeezing plate (14); and a permanent magnet (17) is fixedly connected to the bottom of the switching plate (8).

7. The intelligent diagnosis and leak location system for vacuum degree of a vacuum heat exchanger according to claim 6, characterized in that: The porous absorbent block (13) has a set of elastic protrusions (18) evenly distributed on its surface; the squeezing plate (14) has a set of elastic spikes (19) evenly distributed on the side near the switching plate (8).

8. The intelligent diagnosis and leak location system for vacuum degree of a vacuum heat exchanger according to claim 6, characterized in that: A return pipe (20) is connected between the bottom of the switching slot (7) and the heat exchanger shell (1).

9. A method for intelligent diagnosis and leak location of vacuum degree in a vacuum heat exchanger, wherein the method employs the intelligent diagnosis and leak location system described in any one of claims 1-8, characterized in that: Includes the following steps: S1. Through the sensor array integrated on the inner wall of the vacuum heat exchanger housing (1), the absolute pressure signal, temperature distribution signal and acoustic vibration signal are collected simultaneously. S2. Establish a dynamic baseline prediction model for vacuum degree decay based on the historical normal operation data of the equipment, and compare the real-time collected vacuum degree data with the dynamic baseline prediction value in real time. S3. Analyze and compare the results. If the actual vacuum decay rate continues and deviates significantly from the predicted baseline, it is determined that the vacuum system has an abnormal leakage mode. S4. When an abnormal leak is detected, the acoustic sensor array is activated, and the TDOA positioning algorithm based on the time difference of arrival is used to calculate the spatial location of the leak source. S5. Determine the leakage level based on the decay rate of the abnormal leakage, and execute the corresponding automatic maintenance compensation or alarm operation.

10. The intelligent diagnosis and leak location method for vacuum degree of a vacuum heat exchanger according to claim 9, characterized in that: In step S4, the TDOA positioning algorithm includes: preprocessing the acoustic signal, calculating the time delay difference of the signal reaching different sensors, constructing a hyperbola equation with the sensor pair as the focus, and determining the leak location by solving the intersection area of ​​multiple hyperbolas.

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