Energy-saving heat exchange device with self-cleaning function

Abstract

This invention relates to the field of heat exchange device technology and discloses an energy-saving heat exchange device with self-cleaning function, including a shell, heat exchange tube bundle, baffle plate, cleaning component, and control component. The cleaning component includes a motor-driven positive and negative threaded screw and two cleaning plates with openings fitted onto the heat exchange tube bundle. Cleaning brushes are provided inside the openings, which can achieve online descaling through mechanical scraping. The control component integrates a multi-dimensional data acquisition module and a three-level correction logic: a flow field fluctuation off-target correction module introduces the theoretical clean heat transfer coefficient to distinguish between flow fluctuations and actual scaling; a mechanical load verification correction module cross-verifies based on pre-detection power consumption increments; an energy efficiency balance final correction module determines the cleaning economy through net benefit assessment; and an adaptive execution drive module dynamically adjusts the motor speed according to the scaling condition. This invention achieves accurate identification of scaling conditions and on-demand energy-saving cleaning, avoids frequent ineffective actions, and ensures long-term stable heat exchange efficiency.

Description

Technical Field

[0001] This invention relates to the field of heat exchange device technology, specifically to an energy-saving heat exchange device with self-cleaning function. Background Technology

[0002] As core equipment for heat transfer and recovery in industrial production and HVAC systems, heat exchangers directly affect the energy consumption and operational economy of the entire system due to the stability of their heat exchange efficiency. During actual operation, when the shell-side medium (especially industrial circulating water, process condensate, or fluids containing trace suspended solids) flows through the outer wall of the heat exchanger tube bundle, it is inevitably affected by factors such as temperature changes, uneven flow velocity distribution, and reduced solubility of salts in the water. This inevitably leads to the gradual formation of a fouling layer on the surface of the heat exchanger tubes, primarily composed of carbonates, silicates, or biological slime. This fouling layer typically has a low thermal conductivity; even a very thin layer can significantly increase the thermal resistance, resulting in a substantial decrease in the overall heat transfer coefficient of the device.

[0003] To maintain heat exchange performance under design conditions, mechanical or chemical cleaning methods involving periodic shutdowns are commonly used in engineering practice. Mechanical cleaning requires disassembling the end caps or removing the tube bundles, which not only consumes significant manpower and maintenance time but also disrupts the production line or heating system, resulting in substantial economic losses for continuous production. Chemical cleaning, on the other hand, dissolves scale by injecting acidic or alkaline cleaning agents into the shell side. While this can achieve online or semi-online operation to some extent, the treatment of cleaning wastewater presents environmental compliance challenges. Furthermore, improper chemical formulations and soaking times can easily cause irreversible intergranular corrosion or pitting damage to metal pipes and welds, shortening the overall service life of the equipment.

[0004] In recent years, some technical solutions have attempted to integrate online mechanical descaling mechanisms into heat exchange devices, such as using reciprocating brush or scraper components to periodically scrape the outer wall of the tube bundle. However, existing online cleaning solutions generally have the following shortcomings: First, the drive stroke of the cleaning components is not well matched with the length of the tube bundle, making it difficult to achieve uniform cleaning across the entire length and easily leading to the accumulation of stubborn scale at both ends of the heat exchange tubes or in the dead zone of the baffle. Second, the triggering logic for cleaning actions is relatively simple and crude, often based on timers or a single temperature difference threshold for start-stop control, failing to effectively distinguish between the apparent decrease in heat transfer coefficient caused by natural fluctuations in fluid conditions (such as reduced flow rate or changes in inlet temperature) and the performance degradation caused by actual scaling. This crude judgment mechanism not only easily leads to unnecessary frequent cleaning actions, increasing the mechanical wear of transmission components and drive energy consumption, but may also delay the cleaning opportunity when actual scaling has already occurred due to improper threshold settings, resulting in a significant reduction in energy-saving effects.

[0005] Therefore, how to construct a self-cleaning system for heat exchange devices that can accurately identify the scaling state while taking into account the energy efficiency of the cleaning action itself, while minimizing manual intervention and downtime losses, has become a technical problem that urgently needs to be improved in this field. Summary of the Invention

[0006] In order to solve the technical problems in the prior art, this application provides an energy-saving heat exchange device with self-cleaning function.

[0007] The energy-saving heat exchange device with self-cleaning function provided in this application adopts the following technical solution: it includes an outer shell, which serves as the main pressure-bearing and housing structure of the device, and has an internal accommodating space;

[0008] The heat exchange tube bundle, located inside the shell, consists of multiple metal tubes and is used for heat exchange between the tube side and the shell side for media of different temperatures.

[0009] A baffle plate is fixedly installed inside the outer shell, with its surface arranged at an angle to the axis of the heat exchange tube bundle. It is used to provide radial support for the heat exchange tube bundle and guide the shell-side fluid to flow along a preset path to flush the outer wall of the heat exchange tube bundle.

[0010] The medium inlet and medium outlet are respectively provided on the outer shell for introducing and discharging the shell-side medium;

[0011] A cleaning component, disposed inside the housing, is used to remove dirt deposited on the outer wall of the heat exchange tube bundle by mechanical scraping action;

[0012] A support is fixedly installed at the bottom of the housing to provide support and fixation for the housing;

[0013] The control component is a control system integrating data perception, multi-level logic correction and adaptive execution decision-making functions. It includes a multi-dimensional data acquisition module, an apparent heat transfer feature identification module, a flow field fluctuation off-target correction module, a mechanical load verification and correction module, an energy efficiency balance final correction module and an adaptive execution drive module.

[0014] Preferably, the cleaning component includes:

[0015] A positive and negative threaded screw is rotatably mounted inside the housing, extends axially along the housing, and has a positive threaded section and a negative threaded section with opposite directions of rotation on its shaft surface;

[0016] Two cleaning plates, both plate-shaped structures, each having openings corresponding to the number and spatial arrangement of the heat exchange tube bundle. The two cleaning plates are fitted onto the heat exchange tube bundle through their respective openings. One of the cleaning plates is connected to the positive thread section of the positive and negative threaded screw via an internal thread, and the other cleaning plate is connected to the negative thread section of the positive and negative threaded screw via an internal thread.

[0017] The motor, whose output shaft is connected to the positive and negative thread screw, is used to drive the positive and negative thread screw to rotate, so that the two cleaning plates produce axial displacements in opposite directions;

[0018] The inner edge of the opening is provided with a cleaning brush that is in close contact with the outer wall of the heat exchange tube bundle.

[0019] Preferably, the multi-dimensional data acquisition module is used to acquire in real time the shell-side inlet temperature, shell-side outlet temperature, tube-side inlet temperature, tube-side outlet temperature, shell-side mass flow rate, tube-side mass flow rate, and shell-side inlet and outlet pressure difference.

[0020] Preferably, the apparent heat transfer feature identification module is used to calculate the apparent heat transfer coefficient of the device under the current operating state based on the parameters obtained by the multi-dimensional data acquisition module.

[0021] Preferably, the flow field fluctuation off-target correction module serves as the first-level correction step. It is used to calculate a first correction coefficient, which characterizes the degree of deviation between the apparent heat transfer coefficient and the theoretical clean heat transfer coefficient, by introducing the theoretical clean heat transfer coefficient calculated based on the fluid Reynolds number, so as to distinguish the influence of flow fluctuation factors and actual fouling factors on heat exchange performance.

[0022] Preferably, the flow field fluctuation off-target correction module is further configured to: monitor the pressure difference between the shell side inlet and outlet in real time, and use the ratio of the theoretical clean pressure difference to the measured pressure difference under the current flow rate as a pressure difference correction factor to perform weighted correction on the first correction coefficient, so as to use the pressure difference change to assist in verifying the judgment result of the first-level correction.

[0023] Preferably, the mechanical load verification and correction module serves as a second-level correction step, used to calculate a second correction coefficient by monitoring the increase in mechanical power consumption of the motor during the pre-inspection stroke, in order to assist in verifying the scaling determination result based on the first correction coefficient.

[0024] Preferably, the energy efficiency balance final correction module serves as the third-level correction stage. After confirming the presence of fouling, it calculates a third correction coefficient by constructing a net benefit evaluation logic with heat recovery gain and cleaning execution cost as variables, in order to determine the economics of performing the cleaning operation.

[0025] Preferably, the adaptive execution drive module is used to dynamically adjust the operating speed of the motor according to the scale condition represented by the second correction coefficient after receiving the cleaning execution command.

[0026] Preferably, the surface of the positive and negative threaded screws is coated with a friction-reducing coating; there is a sliding gap between the outer periphery of the cleaning plate and the inner wall of the housing, and a guide ring made of polytetrafluoroethylene is installed on the outer periphery of the cleaning plate to ensure that the cleaning plate maintains perpendicularity to the heat exchange tube bundle during movement.

[0027] In summary, this application includes at least one of the following beneficial technical effects:

[0028] 1. This invention uses a cleaning assembly consisting of a screw with both positive and negative threads and two symmetrically arranged cleaning plates. A single motor can drive the two cleaning plates to produce axial displacements with opposite phases, achieving a scissor motion that moves synchronously toward the center or away from both ends. The cleaning brushes embedded inside the openings of the cleaning plates are in close contact with the outer wall of the heat exchange tube bundle, effectively removing deposited dirt through mechanical scraping. This structure can complete online cleaning without disassembling the equipment or interrupting the heat exchange process, avoiding the reduction in heat exchange efficiency caused by scaling, while eliminating the risk of corrosion to the tube bundle caused by traditional chemical cleaning, ensuring long-term stable operation of the device.

[0029] 2. The control unit sequentially incorporates a flow field fluctuation off-target correction module, a mechanical load verification correction module, and an energy efficiency balance final correction module for three levels of correction judgment. The first level of correction effectively distinguishes the impact of flow fluctuation factors and actual scaling factors on heat exchange performance by introducing theoretical clean heat transfer coefficients calculated based on Reynolds number and shell-side pressure difference as auxiliary verification. The second level of correction monitors the increase in mechanical power consumption of the motor during the pre-inspection stroke and uses the resistance change caused by the scale layer to perform physical-level cross-verification of the scaling judgment results, shielding false triggers caused by changes in medium properties or instrument drift. The third level of correction, after confirming scaling, determines the economic rationality of performing the cleaning operation based on the net benefit evaluation logic of heat recovery gain and cleaning execution cost. This multi-level correction mechanism makes the triggering of cleaning commands more accurate, energy-saving, and reliable.

[0030] 3. The control unit constructs a net benefit assessment function to quantitatively compare the economic value of the additional heat recovered due to the restoration of the heat transfer coefficient in the future time period with the electricity cost consumed by the cleaning action and the maintenance cost deducted from mechanical wear, and calculates the third correction coefficient accordingly; a full cleaning execution command is issued only when the benefit significantly exceeds the expenditure; this mechanism avoids energy waste and equipment life loss caused by frequent ineffective cleaning, and keeps the device in the optimal energy efficiency state throughout the entire operating cycle, reflecting the energy-saving concept of cleaning on demand.

[0031] 4. During the cleaning execution phase, the adaptive execution drive module dynamically adjusts the motor speed based on the scale condition characterized by the mechanical load verification and correction module. When the scale is thick, it operates in a low-speed, high-torque mode to prevent stalling, and in a high-speed mode to improve cleaning efficiency when the scale is thin. At the same time, the control unit integrates a self-learning library based on data annotation. After each cleaning, it automatically calculates the heat transfer coefficient recovery rate and stores it in the database. If the recovery rate is consistently lower than a preset threshold, a self-diagnostic program is triggered. In addition, the device also has a mechanical fault self-check function at the initial startup stage, which can identify foreign object jamming or transmission failure and issue an early warning. These designs together ensure the long-term stable, intelligent, and reliable operation of the device under complex working conditions. Attached Figure Description

[0032] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0033] Figure 2 This is a rear-view stereoscopic structural diagram of the present invention;

[0034] Figure 3 This is a cross-sectional structural diagram of the present invention;

[0035] Figure 4 for Figure 3 Enlarged view of point A in the middle;

[0036] Figure 5 This is a block diagram showing the architecture and logical connection of the control component of the present invention;

[0037] Figure 6 This is a flowchart illustrating the multi-level logic correction and decision-making process in an embodiment of the present invention.

[0038] Figure 7 This is a flowchart illustrating the adaptive execution and self-learning optimization process in an embodiment of the present invention.

[0039] Explanation of reference numerals in the attached drawings: 1. Outer shell; 2. Heat exchange tube bundle; 3. Baffle plate; 4. Medium inlet; 5. Medium outlet; 6. Cleaning component; 61. Threaded screw; 62. Cleaning plate; 63. Opening; 64. Motor; 7. Control component; 8. Support. Detailed Implementation

[0040] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. In addition, the forms of the various structures described in the following embodiments are merely illustrative. The energy-saving heat exchange device with self-cleaning function involved in the present invention is not limited to the structures described in the following embodiments. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] Please see Figures 1-7The energy-saving heat exchange device with self-cleaning function shown is composed of an outer shell 1, a heat exchange tube bundle 2, a baffle plate 3, a medium inlet 4, a medium outlet 5, a cleaning component 6, and a control component 7 as the logic center.

[0042] The outer shell 1 serves as the main pressure-bearing and housing structure of the device. Its material is typically 316L stainless steel or carbon steel with a corrosion-resistant coating, depending on the chemical properties of the heat exchange medium. It has a specific internal space that not only accommodates the core heat exchange components but also provides sufficient mechanical travel for the reciprocating motion of the cleaning component 6. The heat exchange tube bundle 2 is located inside the outer shell 1 and consists of several metal tubes with high thermal conductivity (such as deoxidized phosphorus copper tubes, titanium tubes, or stainless steel corrugated tubes) fixed by a tube sheet. The baffle plate 3 is installed inside the outer shell 1 and serves not only as a radial support structure for the heat exchange tube bundle 2, preventing tube bundle fatigue failure caused by fluid-induced vibration, but also...

[0043] The medium inlet 4 is located on the side wall of the outer shell 1 near one end of the heat exchange tube bundle 2, and is used to introduce the shell-side medium to be exchanged; the medium outlet 5 is located at the bottom of the opposite end of the outer shell 1. This diagonal inlet and outlet arrangement ensures that the shell-side fluid can flow fully through the entire tube bundle area, avoiding the generation of heat exchange dead zones; at the same time, the bottom medium outlet 5 facilitates the complete drainage of residual liquid in the shell side by gravity when the machine is shut down for maintenance or medium replacement, preventing deposits from solidifying during shutdown.

[0044] The cleaning component 6, as the core mechanism for physical descaling in this invention, specifically includes a threaded screw 61, two symmetrically arranged cleaning plates 62, and a motor 64. The threaded screw 61 is rotatably mounted on the central axis inside the outer casing 1 via a bearing seat and extends axially along the outer casing 1. Both cleaning plates 62 are high-strength composite plate structures with openings 63 on their surfaces that are identical in number and spatial arrangement to the heat exchange tube bundle 2. The cleaning plates 62 are fitted onto the heat exchange tube bundle 2 through these openings 63. The first cleaning plate 62 engages with the threaded section of the threaded screw 61 through its central internal threaded sleeve, while the second cleaning plate 62 engages with... The motor 64 is fixedly installed on the outer end of the housing 1, and its output shaft is connected to the positive and negative thread screw 61 through a magnetic coupling or a mechanical seal coupling. When the motor 64 drives the positive and negative thread screw 61 to rotate, based on the principle of helical transmission, the two cleaning plates 62 will generate axial displacements with opposite phases, that is, realize synchronous scissor motion towards the center or away from both ends. This motion mode can ensure full coverage mechanical brushing of the entire tube bundle length range under the drive of a single motor. It should be noted that the inner edge of the opening 63 of the cleaning plate 62 is inlaid with a cleaning brush made of wear-resistant material, so that it is in close contact with the outer wall of the heat exchange tube bundle 2, and removes the deposited dirt through mechanical scraping.

[0045] The control component 7 described in this invention is not a simple timer switch, but an intelligent control system integrating multi-dimensional sensing, multi-level logic correction, and adaptive execution decision-making. The control component 7 acquires basic physical parameters of the device in real time through a high-sampling-frequency multi-dimensional data acquisition module. Specifically, it acquires the shell-side inlet temperature using PT1000-level high-precision temperature sensors installed at the medium inlet 4 and medium outlet 5. and shell-side outlet temperature Simultaneously acquire the tube-side inlet temperature of heat exchanger tube bundle 2. and the tube-side outlet temperature of heat exchanger tube bundle 2 Simultaneously, the shell-side mass flow rate is monitored in real time using an electromagnetic flowmeter or an ultrasonic flowmeter. and tube mass flow In addition, the multi-dimensional data acquisition module also acquires the inlet and outlet pressure difference of the shell side in real time through a differential pressure transmitter. ;

[0046] The apparent heat transfer feature identification module is the first layer of logic in the control unit 7, which calculates the apparent heat transfer coefficient at the current moment based on the principle of heat balance. The computational logic is described as follows:

[0047] First, calculate the instantaneous heat transfer load of the heat exchange device. :

[0048] ;

[0049] In this formula, This indicates the instantaneous heat flow rate of the heat exchanger, measured in watts (W).

[0050] This indicates the mass flow rate of the shell-side medium, expressed in kilograms per second (kg / s).

[0051] This represents the isobaric specific heat capacity of the shell-side medium at the current average temperature, expressed in joules per kilogram of Kelvin (J / (kg·K)).

[0052] Next, the logarithmic mean temperature difference is automatically calculated. To reflect the average driving force of the heat exchange process:

[0053] ;

[0054] in, The logarithmic mean temperature difference is expressed in Kelvin (K).

[0055] Finally, considering the total heat exchange area of ​​heat exchange tube bundle 2 (Unit: square meters) The apparent heat transfer coefficient was calculated. :

[0056] ;

[0057] The unit is watts per square kelvin (W / ( ·K));

[0058] To eliminate pseudo-scaling interference caused by fluctuations in operating conditions (such as a decrease in circulating water flow), the flow field fluctuation off-target correction module is introduced as the first-level correction step; this module calculates the theoretical clean heat transfer coefficient at the current flow rate based on the fluid dynamics criterion equations. First, define the characteristic Reynolds number. :

[0059] ;

[0060] in, The shell-side equivalent diameter (m); Fluid mass flow rate (kg / ( ·s)); The dynamic viscosity of the fluid at the bulk temperature (Pa·s);

[0061] Theoretical clean heat transfer coefficient The calculation follows the following correlation:

[0062] ;

[0063] In this formula, The reference structural coefficient reflects the inherent influence of the heat exchanger's geometry on the flow field.

[0064] It needs to be further explained that, The reference structural coefficient is a dimensionless constant that characterizes the inherent influence of the device's inherent geometry on shell-side fluid flow and convective heat transfer processes. Its value is uniquely determined solely by the device's inherent geometric parameters, such as the inner diameter of the shell, the specifications and arrangement of the heat exchange tube bundles, the shear rate and spacing of the baffles, and the effective heat transfer length. It is independent of fluid properties, operating conditions, and scaling conditions, and remains constant throughout the entire lifespan of the device without permanent changes to its geometry. Those skilled in the art can determine its specific value corresponding to the structure of this device through cleanroom heat transfer performance calibration experiments specified in industry standard GB / T 27698, correlation fitting of convective heat transfer criterion numbers, or CFD numerical simulation methods.

[0065] Let be the Prandtl number of the fluid;

[0066] These are the Reynolds number index, Prandtl number index, and viscosity correction index, respectively. These parameters were obtained through regression analysis of experimental data from the initial operation phase of the heat exchange device.

[0067] First correction factor Defined as the ratio of apparent performance to theoretical performance:

[0068] ;

[0069] when When the pressure drops below a first preset threshold (e.g., 0.85), cleaning is not initiated immediately; instead, a suspicion of scaling is identified. To further improve the accuracy of the determination, the control unit 7 monitors the pressure difference between the inlet and outlet of the shell side. The changes were used for auxiliary verification; the corrected first coefficient Represented as:

[0070] ;

[0071] in, This represents the theoretical clean pressure differential at the current flow rate.

[0072] It should be further clarified that the theoretical clean pressure difference at the current flow rate is a dynamically calculated value based on the flow resistance characteristic parameters calibrated under clean operating conditions and combined with the current real-time operating conditions. It refers to the theoretical pressure difference between the shell-side inlet and outlet when the device is clean, scale-free, and the flow channels are unblocked, under operating conditions that are completely consistent with the current shell-side medium flow rate and medium properties. Its calibration is based on the industry standard GB / T 27698 "Test Methods for Heat Transfer Performance of Heat Exchangers". Those skilled in the art can obtain the shell-side flow resistance characteristic correlation by fitting multiple sets of measured shell-side flow rate-pressure difference data under steady-state operating conditions in a clean state, and then substitute this data into the real-time collected current shell-side mass flow rate to calculate the theoretical pressure difference. This value can also be obtained by CFD numerical simulation method targeting the structure of this device.

[0073] This is a pressure sensitivity index, typically ranging from 0.25 to 0.35.

[0074] The mechanical load verification and correction module, as the second-level correction stage, operates on the engineering logic that scaling inevitably leads to a slight increase in the outer diameter and surface roughness of the heat exchange tube bundle 2, thereby generating additional mechanical resistance when the cleaning plate 62 moves. This module monitors the output current of the motor 64 in real time via a frequency converter. Define the second correction factor. ;

[0075] ;

[0076] in, Pre-inspection travel time (s);

[0077] The driving voltage (V) remains constant during constant speed operation in a single pre-inspection stroke;

[0078] The reference power consumption (J) for the cleaning component 6 to operate at the same speed and displacement as the pre-inspection stroke under clean conditions.

[0079] like Indicator efficiency decreased, and If the power consumption exceeds the second preset threshold (e.g., a 15% increase), it is confirmed as genuine scaling; if If there is no obvious change, it is determined that the decrease in efficiency is caused by changes in the physical properties of the medium or sensor drift, thus blocking the cleaning command;

[0080] The energy efficiency balance final correction module, as the third-level correction stage, aims to resolve the contradiction of wasting energy in the pursuit of cleanliness; this module constructs an evaluation function for net benefit efficiency. Used to calculate in the predicted future time period Inside, is the heat generated by the cleaning process sufficient to offset its power consumption and wear and tear costs?

[0081] ;

[0082] in, After the cleaning action is performed, The economic value of the additional recovered heat due to the recovery of the heat transfer coefficient per unit time;

[0083] for The time-allocated value is the total electricity cost of motor 64 for a single cleaning cycle within a unit of time. The method for obtaining the time-allocated value is to linearly divide the total electricity cost of a single cleaning cycle into equal parts based on the effective benefit period of the heat transfer coefficient after cleaning. Internal values ​​are constant;

[0084] for The time-allocated value is the maintenance cost calculated based on the reduction in mechanical life caused by a single cleaning action per unit time. This time-allocated value is obtained by linearly dividing the total wear cost of vulnerable parts corresponding to a single cleaning action into equal parts over a revenue cycle consistent with electricity costs. Internal values ​​are constant;

[0085] Third correction factor Defined as:

[0086] ;

[0087] Only when When the third preset threshold is continuously exceeded (usually set to 1.5, meaning the benefit must exceed 50% of the expenditure), a final full cleaning execution instruction is issued.

[0088] During the execution phase, the adaptive execution driver module, according to The motor speed 64 is dynamically adjusted based on the hardness and thickness of the scale layer. :

[0089] ;

[0090] in, The reference speed;

[0091] The resistance sensitivity coefficient is a dimensionless, fixed preset value. Its value is obtained by regression analysis of experimental data from clean operating conditions and simulated scaling conditions during the initial operation of the device. It typically ranges from 1.5 to 3.0. This algorithm ensures that when the scale layer is thick, the motor 64 operates in a low-speed, high-torque mode to prevent stalling or damage to the brushes; when the scale layer is thin, it operates in a high-speed mode to improve cleaning efficiency.

[0092] In a preferred embodiment of the present invention, the control component 7 also integrates a self-learning library based on data annotation; after each cleaning task is completed, the heat transfer coefficient recovery rate is automatically calculated. :

[0093] ;

[0094] in, and These are the steady-state heat transfer coefficients measured before and after the cleaning process; the system will... As tags, these are combined with fluid conditions and load characteristics prior to the cleaning process to form a feature vector, which is then stored in the database. This is a dimensionless parameter used to characterize the effective recovery of heat exchange performance after a single cleaning action. A value closer to 1 indicates better cleaning effect and mechanical performance; if... If the value remains below the fourth preset threshold for an extended period, this threshold is a fixed preset value determined based on engineering practice experience in the shell-and-tube heat exchanger industry, combined with the energy-saving design goals of this device and the rated performance of the self-cleaning mechanism. The standard value is 0.7. This will automatically trigger a self-diagnostic program to check whether the cleaning brush is excessively worn and to correct the weighting coefficient for the next cycle.

[0095] In terms of mechanical design, the surface of the positive and negative thread screw 61 is coated with a diamond-like carbon anti-friction coating to reduce the frictional power consumption of the screw drive and extend its service life; a sliding gap of 0.5mm-1.0mm is maintained between the outer periphery of the cleaning plate 62 and the inner wall of the outer shell 1, and a polytetrafluoroethylene guide ring is installed to ensure that the cleaning plate always maintains its perpendicularity to the heat exchange tube bundle 2 during movement and avoids jamming;

[0096] Furthermore, the control component 7 described in this invention also has fault self-diagnosis and early warning functions during operation; at the initial stage of motor 64 startup, the control component 7 will drive the forward and reverse threaded screw 61 to perform a small pulse reciprocating motion of 5 degrees in each direction; if at this time the current feedback shows an abnormal increase in resistance torque, but the apparent heat transfer coefficient is low... If no degradation is displayed, it will be automatically determined to be due to foreign object obstruction or mechanical transmission failure rather than scaling, and an audible and visual alarm will be issued immediately.

[0097] In specific engineering applications, the hardware carrier of the control unit 7 adopts a high-performance embedded ARM processor with an AD sampling accuracy of 24 bits, ensuring sensitive capture of minute temperature and pressure fluctuations; all control algorithm logic resides in non-volatile memory in firmware form; the device has reserved RS485 and industrial Ethernet interfaces, supports Modbus TCP protocol, and can upload operating data to the factory cloud database in real time to realize collaborative optimization of multiple heat exchange devices.

[0098] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0099] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An energy-saving heat exchange device with self-cleaning function, characterized in that, include: The outer shell (1) serves as the main pressure-bearing and housing structure of the device, and its interior has a accommodating space; The heat exchange tube bundle (2) is located inside the shell (1) and consists of multiple metal tubes for heat exchange between the tube side and the shell side of the medium at different temperatures. The baffle (3) is fixedly installed inside the outer shell (1), and its plate surface is arranged at an angle to the axis of the heat exchange tube bundle (2). It is used to provide radial support for the heat exchange tube bundle (2) and guide the shell-side fluid to flow along a preset path to scour the outer wall of the heat exchange tube bundle (2). The medium inlet (4) and the medium outlet (5) are respectively provided on the outer shell (1) for introducing and discharging the shell-side medium; A cleaning component (6) is disposed inside the housing (1) and is used to remove dirt deposited on the outer wall of the heat exchange tube bundle (2) by mechanical scraping. The support (8) is fixedly installed at the bottom of the outer shell (1) to provide support and fixation for the outer shell (1); The control component (7) is a control system that integrates data perception, multi-level logic correction and adaptive execution decision-making functions. It includes a multi-dimensional data acquisition module, an apparent heat transfer feature identification module, a flow field fluctuation off-target correction module, a mechanical load verification correction module, an energy efficiency balance ultimate correction module and an adaptive execution drive module. The multi-dimensional data acquisition module is used to acquire in real time the shell-side inlet temperature, shell-side outlet temperature, tube-side inlet temperature, tube-side outlet temperature, shell-side mass flow rate, tube-side mass flow rate, and shell-side inlet and outlet pressure difference. The apparent heat transfer feature identification module is used to calculate the apparent heat transfer coefficient of the device under the current operating state based on the parameters obtained by the multi-dimensional data acquisition module. The flow field fluctuation off-target correction module, as the first-level correction stage, is used to calculate a first correction coefficient to characterize the deviation between the apparent heat transfer coefficient and the theoretical clean heat transfer coefficient by introducing the theoretical clean heat transfer coefficient calculated based on the fluid Reynolds number, so as to distinguish the influence of flow fluctuation factors and actual fouling factors on heat transfer performance. The flow field fluctuation off-target correction module is also configured to: monitor the pressure difference between the shell side inlet and outlet in real time, and use the ratio of the theoretical clean pressure difference to the measured pressure difference under the current flow rate as a pressure difference correction factor to perform weighted correction on the first correction coefficient, so as to use the pressure difference change to assist in verifying the judgment result of the first-level correction. The mechanical load verification and correction module serves as the second-level correction step. It is used to monitor the increase in mechanical power consumption of the motor (64) during the pre-inspection stroke and calculate the second correction coefficient to assist in verifying the scaling judgment result based on the first correction coefficient. The energy efficiency balance final correction module, as the third-level correction stage, is used to determine the economics of performing cleaning operations after confirming the existence of scaling by constructing a net benefit evaluation logic with heat recovery gain and cleaning execution cost as variables. The adaptive execution drive module is used to dynamically adjust the operating speed of the motor (64) according to the scale condition represented by the second correction coefficient after receiving the cleaning execution command.

2. The energy-saving heat exchange device with self-cleaning function according to claim 1, characterized in that, The cleaning component (6) includes: A positive and negative threaded screw (61) is rotatably mounted inside the housing (1), extending along the axial direction of the housing (1), and its shaft surface has a positive thread section and a negative thread section with opposite directions of rotation; Two cleaning plates (62) are plate-shaped structures. Each cleaning plate (62) has openings (63) corresponding to the number and spatial arrangement of the heat exchange tube bundle (2). The two cleaning plates (62) are fitted onto the heat exchange tube bundle (2) through their respective openings (63). One of the cleaning plates (62) is connected to the positive thread section of the positive and negative thread screw (61) through an internal thread, and the other cleaning plate (62) is connected to the negative thread section of the positive and negative thread screw (61) through an internal thread. The motor (64) has its output shaft connected to the positive and negative thread screw (61) for driving the positive and negative thread screw (61) to rotate so that the two cleaning plates (62) produce axial displacements in opposite directions; A cleaning brush is provided at the inner edge of the opening (63) and is closely attached to the outer wall of the heat exchange tube bundle (2).

3. The energy-saving heat exchange device with self-cleaning function according to claim 2, characterized in that, The surface of the positive and negative threaded screw (61) is coated with a friction-reducing coating; there is a sliding gap between the outer periphery of the cleaning plate (62) and the inner wall of the outer shell (1), and a guide ring made of polytetrafluoroethylene is installed on the outer periphery of the cleaning plate (62) to ensure that the cleaning plate (62) remains perpendicular to the heat exchange tube bundle (2) during movement.

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