Multi-mode double-channel heat exchange system, heat exchanger and control method

Abstract

The multi-mode double-flow-channel heat exchange system comprises a first heat exchanger and a second heat exchanger which are of the same structure, and each heat exchanger is provided with a first flow channel and a second flow channel which are isolated from each other; the first fluid source and the second fluid source respectively provide different temperature characteristics, and the two fluids have the same or different physical and chemical properties; the fluid pipeline network is connected with a fluid source and a heat exchanger runner through a valve group; and the control system periodically switches the valve group, so that the system alternately operates between the first working mode and the second working mode. Through the design of the independent flow channels, energy loss and mutual pollution caused by mixing of cold and hot fluid are avoided, the function switching transition time is greatly shortened, and the time average efficiency of continuous operation is improved; the energy loss caused by incomplete emptying of the runner is minimized, and the initial energy efficiency after switching is improved; a stable working state can be quickly entered only by exchanging fluid and air paths, and the efficiency valley caused by thermal inertia of traditional equipment is reduced to the minimum.

Description

Technical Field

[0001] This invention relates to the field of heat exchange equipment technology, and in particular to a multi-mode dual-channel heat exchange system, heat exchanger and control method. Background Technology

[0002] Heat exchangers are commonly used devices in industrial fields for heat and mass exchange between hot and cold media. Their heat exchange efficiency in actual processes is often affected by the heat exchange structure. Solid dryer coated heat exchangers have become a research focus in recent years due to their potential for utilizing low-quality industrial waste heat. Their working principle is based on a cycle of two processes: adsorption and regeneration. During adsorption, hot, humid air flows through the coating, moisture is adsorbed, and heat is released. At this time, a cold fluid is introduced into the tube to remove the adsorption heat, achieving air cooling and dehumidification. During regeneration, a hot fluid is introduced into the tube to provide desorption heat to the desiccant, causing it to desorb moisture and restore its adsorption capacity. The desorbed moisture is carried away by the regeneration airflow.

[0003] To achieve continuous output, such heat exchangers must periodically switch between adsorption and regeneration modes. Traditional designs typically employ a single flow channel, where cold and hot fluids alternately flow through the same pipe, as seen in heat exchangers disclosed in patents CN215062509U and CN119895221A. This design has a significant drawback: at the moment of mode switching, the fluid remaining in the pipe from the previous flow (cold or hot) directly mixes with the newly flowing fluid (hot or cold). This mixing not only causes considerable energy loss and reduces system efficiency, but also leads to cross-contamination if the cold and hot source media have different properties, affecting system operational stability and media quality.

[0004] Furthermore, for applications like desiccant-coated heat exchangers, which require frequent, periodic switching between 'pure cooling dehumidification' and 'pure heating regeneration' modes, the residual medium from the previous cycle in each flow channel experiences a 'cold-hot collision' with the newly flowing medium during the switching process, resulting in significant initial energy loss. Simultaneously, the thermal inertia of the heat exchanger body due to the residual medium and its own heat storage causes the system to require a relatively long transition time before reaching efficient operating conditions. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the technical problem to be solved by the present invention is to provide a multi-mode dual-channel heat exchange system, heat exchanger and control method, which can effectively avoid the mixing and mutual contamination of hot and cold fluids and significantly reduce the loss of cold or heat caused by the switching of working modes.

[0006] This invention proposes a multi-mode dual-channel heat exchange system, comprising: a first heat exchanger and a second heat exchanger, having identical structures and each having a first flow channel and a second flow channel isolated from each other; a first fluid source for providing a first fluid; a second fluid source for providing a second fluid, wherein the first fluid and the second fluid have different temperature characteristics, and the two fluids have the same or different physicochemical properties; a fluid piping network connecting the fluid source and the flow channels of the heat exchanger via valve groups; and a control system that periodically switches the valve groups to allow the system to operate alternately between a first operating mode and a second operating mode; wherein: in the first operating mode, the first fluid source is connected to the first flow channel of the first heat exchanger, and the second fluid source is connected to the second flow channel of the second heat exchanger; in the second operating mode, the first fluid source is connected to the first flow channel of the second heat exchanger, and the second fluid source is connected to the second flow channel of the first heat exchanger; in either the first or second operating mode, a single heat exchanger circulates only the first fluid or the second fluid.

[0007] Preferably, the first fluid is a cold fluid with a temperature lower than the ambient temperature, and the second fluid is a hot fluid with a temperature higher than the ambient temperature; or, the first fluid is a hot fluid with a temperature higher than the ambient temperature, and the second fluid is a cold fluid with a temperature lower than the ambient temperature.

[0008] Preferably, it further includes a fan unit; in the first operating mode, the fan unit provides the air to be treated to the first heat exchanger and provides the regenerated air to the second heat exchanger; in the second operating mode, the fan unit provides the air to be treated to the second heat exchanger and provides the regenerated air to the first heat exchanger.

[0009] Preferably, the first flow channel and the second flow channel are sloped along the flow direction.

[0010] Preferably, the control system is further configured to execute an auxiliary operating mode in which the control switching valve group is configured to allow fluids supplied by the first fluid source and the second fluid source to flow simultaneously through a designated heat exchanger.

[0011] A second aspect of the present invention provides a dual-channel heat exchanger for any of the above embodiments, comprising: a shell;

[0012] A first tube bundle and a second tube bundle are disposed in the housing in a mutually isolated manner. The first tube bundle forms a first flow channel, and the second tube bundle forms a second flow channel. The first flow channel and the second flow channel are both provided with a slope along the flow direction.

[0013] Preferably, the device further includes multiple heat exchange fins, which are fixedly connected to the first tube bundle and the second tube bundle, and gaps are formed between the heat exchange fins to allow air to pass through.

[0014] Preferably, the surface of the heat exchange fins is coated with a solid desiccant coating.

[0015] A third aspect of the present invention provides an operation control method for a heat exchange system as described in any of the above embodiments, comprising the following steps:

[0016] The control switching valve group enables the system to enter the first working mode, in which the first heat exchanger is circulated with the first fluid and the second heat exchanger is circulated with the second fluid.

[0017] After a first predetermined time, the valve group is controlled to switch to a second operating mode, wherein the second heat exchanger is circulated with a first fluid, and the first heat exchanger is circulated with a second fluid;

[0018] After a second predetermined time, the valve group is controlled to switch back to the first working mode, and this cycle is repeated.

[0019] Preferably, the method further includes a step of optimizing the first predetermined time or the second predetermined time. The optimization step includes: establishing a three-dimensional geometric model of the dual-channel heat exchanger; setting simulation boundary conditions and solving them according to the operating conditions corresponding to the operation control method; analyzing and determining the heat exchange effect of the dual-channel heat exchanger based on the obtained temperature field, velocity field, and pressure field data; and optimizing the configuration and predetermined time of the dual-channel heat exchanger based on the analysis results.

[0020] As described above, the multi-mode dual-channel heat exchange system, heat exchanger, and control method of the present invention have the following beneficial effects:

[0021] This invention controls two identical heat exchangers to periodically switch between a first and a second operating mode, ensuring that each heat exchanger carries only a single type of fluid in either mode. This system, in principle, avoids the "shutdown-draining-charging-startup" process required for switching within a single heat exchanger in traditional systems. This allows one heat exchanger to perform its primary function (such as cooling and dehumidification) while the other is already prepared for the next function switch (such as heating and regeneration) (pre-cooling or pre-heating), significantly shortening the overall system transition time and substantially improving the time-averaged efficiency of continuous operation.

[0022] This invention features slopes in both the first and second flow channels along the flow direction, allowing residual fluid to self-drain under gravity after the fluid pump stops. This structural feature directly reduces the degree of heat exchange (heat cancellation) between the residual fluid and the fluid flowing into the next mode, thereby minimizing direct energy loss due to incomplete channel dredging and improving initial energy efficiency after each switch. Furthermore, the independence of the first and second flow channels helps to minimize energy loss and cross-contamination caused by the mixing of hot and cold fluids, enhancing the overall stability of the system.

[0023] This invention constructs a dual-heat exchanger alternating system with air circulation and a sloped flow channel. When applied to desiccant dehumidification scenarios (such as those combined with desiccant coatings), this system spatially separates the functions of "adsorption cooling" and "regeneration heating," while temporally connecting them. While one heat exchanger is performing adsorption, the other is being preheated and regenerating, thus overcoming its structural thermal inertia. When switching, only the fluid and air paths need to be exchanged, and the system can quickly enter a new stable operating state, thereby minimizing the prolonged performance dips caused by the significant thermal inertia of traditional single-unit systems.

[0024] This invention, through a control system configured with executable auxiliary operation modes, allows users to initiate specific processes as needed, such as uniform preheating during system startup or performance diagnostics during maintenance. In addition to basic alternating operation, the system can also perform state pre-tuning and fault diagnosis, improving its practicality and reliability. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the first working mode of a multi-mode dual-channel heat exchange system provided in an embodiment of the present invention.

[0026] Figure 2 This is a schematic diagram of the second operating mode of a multi-mode dual-channel heat exchange system provided in an embodiment of the present invention.

[0027] Figure 3 This is a schematic diagram of the auxiliary working mode of a multi-mode dual-channel heat exchange system provided in an embodiment of the present invention.

[0028] Figure 4 This is a schematic diagram of the structure of a dual-channel heat exchanger for a multi-mode dual-channel heat exchange system provided in an embodiment of the present invention.

[0029] Figure 5 Provided for an embodiment of the present invention Figure 4 Exploded view.

[0030] Figure 6 This is a schematic cross-sectional view of the first and second tube bundles of the present invention.

[0031] Figure 7 This is a schematic cross-sectional view of the heat exchange fins of the present invention.

[0032] Figure 8 The pressure distribution diagram of the air flow channel of a dual-channel heat exchanger provided in an embodiment of the present invention.

[0033] Figure 9 Temperature distribution diagram of fins in a dual-channel heat exchanger provided in an embodiment of the present invention.

[0034] Figure 10 An air velocity distribution diagram of a dual-channel heat exchanger provided in an embodiment of the present invention.

[0035] Figure 11 This is a comparison diagram showing the effect of tube bundle cross-sectional shape on heat transfer according to an embodiment of the present invention.

[0036] Figure 12 This is a diagram illustrating the effect of wind speed on outlet air temperature, provided as an embodiment of the present invention.

[0037] Explanation of reference numerals in the attached figures:

[0038] 100. Shell; 110. First tube bundle; 120. Second tube bundle; 130. Heat exchange fins. Detailed Implementation

[0039] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0040] It should be understood that the structures, proportions, sizes, etc., illustrated in the accompanying drawings of this specification are merely for illustrative purposes to aid those skilled in the art in understanding and reading the content disclosed herein, and are not intended to limit the conditions under which the invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to the size, without affecting the effects and objectives achieved by the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms used in this specification, such as "upper," "lower," "left," "right," and "middle," are merely for clarity of description and are not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.

[0041] like Figures 1 to 2As shown, an embodiment of a multi-mode dual-channel heat exchange system for industrial or civil heat dissipation / cooling includes a first heat exchanger, a second heat exchanger, a first fluid source, a second fluid source, a fluid piping network, and a control system. The first and second heat exchangers have identical structures and each has a first and second flow channel that are isolated from each other. The first fluid source provides a first fluid, which can be either a heat source or a cold source. The second fluid source provides a second fluid, which can be either a cold source or a heat source, as long as the temperature properties of the first and second fluids are different; this embodiment does not limit this. Besides temperature, other properties can also differ; for example, the first fluid can be water, and the second fluid can be refrigerant R134a. The fluid piping network connects the fluid sources (i.e., the first and second fluid sources) to the flow channels of the heat exchangers (i.e., the first and second heat exchangers) via valve groups. The control system can periodically switch the valve groups, allowing the system to alternate between a first operating mode and a second operating mode. In either the first or second operating mode, a single heat exchanger only circulates the first fluid or the second fluid. Understandably, in any operating mode, only one type of fluid (the first fluid or the second fluid) is allowed to circulate within the first or second heat exchanger.

[0042] Furthermore, the first fluid is not limited to water, ammonia, Freon, carbon dioxide, etc.; the second fluid is not limited to water, heat transfer oil, steam, etc.

[0043] Preferably, the first fluid source can be a water-cooled refrigeration unit, and the second fluid source can be a solar heating system; or, the first fluid source can be a solar heating system, and the second fluid source can be a water-cooled refrigeration unit.

[0044] Preferably, the first fluid is a cold fluid with a temperature lower than the ambient temperature, and the second fluid is a hot fluid with a temperature higher than the ambient temperature; or, the first fluid is a hot fluid with a temperature higher than the ambient temperature, and the second fluid is a cold fluid with a temperature lower than the ambient temperature.

[0045] For ease of understanding, let's take the example of a first fluid source preferably being a cold source and a second fluid source being a heat source. The pipeline from the first fluid source entering the heat exchanger (including the first and second heat exchangers) is sequentially equipped with a filter, a cold fluid pump, a flow meter, and a pressure gauge. Similarly, the pipeline from the second fluid source entering the heat exchanger is sequentially equipped with a filter, a hot fluid pump, a flow meter, and a pressure gauge. The valve assembly includes solenoid valves A1-A6 on the cold-side pipeline and solenoid valves B1-B6 on the hot-side pipeline.

[0046] In the first operating mode, the first fluid source is connected to the first flow channel of the first heat exchanger, and the second fluid source is connected to the second flow channel of the second heat exchanger. Specifically, as follows: Figure 1As shown, the control system opens solenoid valves A1 and A2, and closes solenoid valves A3, A4, A5, and A6, allowing the first fluid to be pumped into the first heat exchanger via a cold fluid pump. Simultaneously, the control system opens solenoid valves B4 and B5, and closes solenoid valves B1, B2, B3, and B6, causing the first and second fluids to circulate in the directions of the red arrows. Furthermore, the desiccant coating on the first heat exchanger is in an adsorbed state, used for cooling and dehumidification to cool the air at the first heat exchanger; the desiccant coating on the second heat exchanger is in a regenerated state, having been preheated to complete its regeneration.

[0047] After the first working mode has been running for a certain period of time, the valve group needs to be controlled by the control system to switch from the first working mode to the second working mode.

[0048] After the mode conversion, in the second operating mode, the first fluid source is connected to the first flow channel of the second heat exchanger, and the second fluid source is connected to the second flow channel of the first heat exchanger. Specifically, as follows: Figure 2 As shown, the control system opens solenoid valves A4, A5, B1, and B2, and closes solenoid valves A1, A2, A3, A6, and B4, B5, B3, and B6. Consequently, the desiccant coating on the first heat exchanger is in a regenerated state, having been preheated and regenerated; the desiccant coating on the second heat exchanger is in an adsorbed state, used for cooling and dehumidification to cool the air at the second heat exchanger. The operating states of the first and second operating modes are detailed in Table 1.

[0049] Table 1. Operating Mode Status Table of Dual-Channel Heat Exchange System

[0050]

[0051] This embodiment realizes dual-mode dual-channel heat exchange of air-hot fluid and air-cold fluid within the same heat exchanger.

[0052] It should be noted that the time for switching from the first working mode to the second working mode can be determined according to the actual situation, and this embodiment does not impose a limitation.

[0053] This embodiment avoids the "shutdown-evacuation-charging-startup" process required for switching functions within a single heat exchanger in the traditional way. This allows one heat exchanger to perform its main function (such as cooling and dehumidification) while the other is already prepared for the next function switch (such as heating and regeneration) (pre-cooling or preheating), thereby greatly shortening the transition time of the overall system function switch and significantly improving the time-average efficiency of continuous operation.

[0054] In one embodiment, such as Figure 1As shown, the multi-mode dual-channel heat exchange system also includes a fan unit. In the first operating mode, the fan unit provides the air to be treated to the first heat exchanger and the regenerated air to the second heat exchanger. When the air to be treated flows through the air channel to the first heat exchanger, the desiccant coating on the first heat exchanger is in an adsorbed state, cooling and dehumidifying the air to be treated, and finally leaving the air channel to enter the next step of the refrigeration process. Since the second fluid source (heat source) enters the second heat exchanger, it heats the desiccant coating desorption process. The regenerated air flows through the air channel to the second heat exchanger, thereby carrying away the desorbed moisture and discharging it into the external environment.

[0055] like Figure 2 As shown, when switching from the first operating mode to the second operating mode, in this mode, the fan unit provides regenerated air to the first heat exchanger and air to be treated to the second heat exchanger. As this air flows through the airflow channel into the second heat exchanger, the desiccant coating on the second heat exchanger is in an adsorbed state, thus cooling and dehumidifying the air before it leaves the airflow channel to enter the next step of the refrigeration process. Because the second fluid source (heat source) enters the first heat exchanger, it heats the desiccant coating desorption process. The regenerated air flows through the airflow channel into the first heat exchanger, thereby carrying away the desorbed moisture and discharging it into the external environment.

[0056] When the first fluid source and the second fluid source are interchanged, the principle is the same as in this embodiment, and will not be repeated here.

[0057] It should be noted that the control system controls the valve group to form a first working mode and a second working mode, as detailed above, and will not be repeated here.

[0058] In one embodiment, the first and second flow channels are sloped along the fluid flow direction. In a specific embodiment of the invention, the heat exchanger is installed at an angle, so that the internal first and second tube bundles naturally form a slope. In another embodiment, by setting the inlet and outlet manifolds of the heat exchanger at different heights, the tube bundles themselves remain horizontal while the connecting pipes form an elevation difference, thus achieving the same venting function.

[0059] This embodiment effectively ensures that the fluid in the flow channel automatically flows back to the supply and return pipelines when stationary, ensuring that the residual cold / heat from the previous cycle is quickly discharged from the heat exchanger during mode switching, thereby increasing the effective working (cooling / heating) time of the heat exchanger. This structural feature directly reduces the degree of heat exchange (cold / heat cancellation) between the fluid flowing into the next mode and the residual fluid, thus minimizing direct energy loss caused by incomplete channel evacuation and improving the initial energy efficiency after each switch. In this embodiment, the slope is not limited and can be determined by those skilled in the art based on actual operating conditions.

[0060] In one embodiment, such as Figure 3As shown, the control system can also execute auxiliary operating modes to meet the needs of special operating conditions such as system startup, shutdown, maintenance, and performance monitoring. The auxiliary operating modes are independent of the aforementioned periodically switching main modes and can be activated or deactivated at any time based on system status or operating commands.

[0061] When the system starts in preheating mode, especially during cold starts, particularly in low ambient temperatures or after long-term shutdown, to prevent condensation on the fin surface, desiccant coating failure due to sudden entry of cold fluid, or thermal stress damage to the heat exchanger, the control system can execute the preheating mode. The control system opens solenoid valves B1, B2, B4, and B5. Hot fluid from the second fluid source flows into the second flow channel of the first heat exchanger via solenoid valve B1 and returns to the second fluid source via solenoid valve B2. Simultaneously, hot fluid from the second fluid source flows into the second flow channel of the second heat exchanger via solenoid valve B4 and returns to the second fluid source via solenoid valve B5. At this time, the first flow channels of both heat exchangers are closed, meaning solenoid valves A1 to A6 are closed. Hot fluid flows simultaneously through the hot fluid channels of both heat exchangers, transferring heat through the fins to uniformly raise the entire heat exchanger core to the preset temperature. After preheating is complete, the control system automatically exits the auxiliary mode and enters the periodically switching main mode. This mode effectively avoids the risk of condensation and thermal shock during cold starts, and extends the service life of the desiccant coating and heat exchanger.

[0062] After the system has been running for a long time, in order to assess the degree of degradation of the adsorption performance of the desiccant coating and detect whether the flow channel is blocked or leaking, the control system executes an auxiliary working mode to diagnose the system's executable performance.

[0063] Diagnose the first heat exchanger by opening solenoid valves A1, A2, B1, and B2 via the control system, while simultaneously closing solenoid valves A3, A4, A5, A6, B3, B4, B5, and B6. The first fluid (cold fluid) supplied by the first fluid source flows into the first flow channel of the first heat exchanger via solenoid valve A2 and returns to the first fluid source via solenoid valve A1. Simultaneously, the second fluid supplied by the second fluid source flows into the second flow channel via solenoid valve B1 and returns to the second fluid source via solenoid valve B2.

[0064] Diagnose the second heat exchanger by opening solenoid valves A4, A5, B4, and B5 via the control system, while simultaneously closing solenoid valves A1, A2, A3, A6, B1, B2, B3, and B6. The first fluid (cold fluid) supplied by the first fluid source flows into the first flow channel of the first heat exchanger via solenoid valve A5 and returns to the first fluid source via solenoid valve A4. Simultaneously, the second fluid supplied by the second fluid source flows into the second flow channel via solenoid valve B4 and returns to the second fluid source via solenoid valve B5.

[0065] Temperature, pressure, flow rate, and humidity sensors installed on pipelines and ducts collect real-time data on parameters such as the temperature difference between the inlet and outlet of the cold fluid, the temperature difference between the inlet and outlet of the hot fluid, the air-side pressure drop, and the air outlet moisture content. Based on this measured data, the control system or external diagnostic equipment calculates the current effective heat transfer coefficient of the heat exchanger and the effective adsorption capacity of the desiccant coating, comparing this data with factory baseline values ​​or historical data.

[0066] If the heat transfer coefficient drops below a threshold, it indicates that scaling or blockage exists in the flow channel; if the adsorption capacity drops below a threshold, it indicates that the desiccant coating needs regeneration or has aged and failed. After diagnosis, the system can provide maintenance suggestions or automatically execute an enhanced regeneration program based on the conclusions.

[0067] like Figures 4 to 7 As shown, an embodiment of a dual-channel heat exchanger for a multi-mode dual-channel heat exchange system includes a shell 100, a first tube bundle 110, and a second tube bundle 120. The first tube bundle 110 and the second tube bundle 120 are disposed within the shell 100 in a mutually isolated manner, such that the first tube bundle 110 forms a first flow channel and the second tube bundle 120 forms a second flow channel. The cross-sectional shape of the first tube bundle 110 and the second tube bundle 120 can be a round tube, a flat tube, a square tube, an elliptical tube, etc., with or without internal fins (e.g., ...). Figure 6 (As shown). Both the first and second flow channels have slopes along the flow direction, as detailed above, and will not be repeated here.

[0068] In this embodiment, with the same heat exchange and adsorption area, the heat exchange effects of rhomboid tubes, circular tubes, and flat circular tubes are compared using CFD simulation. Figure 11 As shown, under the same pressure drop, the heat flux density is highest for flat oval tubes, followed by rhomboid tubes, and lowest for round tubes. This means that with the same energy consumption (i.e., power consumption of the fan and water pump), flat oval tubes provide the best heat exchange effect. In other words, to achieve the same heat exchange effect and heat flux density, the heat exchanger with a flat oval cross-section consumes the least power, while the heat exchanger with a round cross-section requires more electrical energy. Therefore, in this embodiment, the first and second tube bundles can preferably be flat oval tubes.

[0069] It should be noted that this embodiment uses a double-row circular tube heat exchanger structure as an example. When the inlet air temperature is 30°C and the chilled water temperature is 26°C, the outlet air temperature changes with the wind speed (e.g., Figure 12 (As shown). As wind speed increases, the rate of decrease in outlet air temperature gradually flattens out. Similarly, the outlet air temperature is also affected by changes in the flow rate of the hot and cold fluids. In actual system operation, the hot and cold fluids should be controlled using detection devices such as anemometers, flow meters, and outlet temperature sensors. By adjusting the wind speed and the flow rate of the hot and cold fluids, the heat exchange and adsorption process of the system can be maintained at a high efficiency, avoiding a mismatch between the power consumption of the fan and pump and the heat exchange / adsorption effect, which would reduce the system's energy efficiency ratio.

[0070] In one embodiment, such as Figure 4 and Figure 5 As shown, the dual-channel heat exchanger also includes multiple heat exchange fins 130, which are fixedly connected to the first tube bundle 110 and the second tube bundle 120, forming gaps between the fins for air passage. The surfaces of the heat exchange fins are coated with a solid desiccant coating. The shape of the heat exchange fins is not limited to straight fins, serrated fins, porous fins, corrugated fins, etc. (e.g.,...) Figure 7 (As shown).

[0071] It should be noted that this embodiment differs from traditional finned tube heat exchangers. The function of the fins is not only to increase the heat exchange area and enhance fluid turbulence to strengthen heat transfer, but also to serve as the heat transfer medium for mode switching, supporting the continuous multi-mode operation of the dual-channel heat exchanger.

[0072] An embodiment of an operation control method for a multi-mode dual-channel heat exchange system includes the following steps:

[0073] S100: Control the switching valve group to put the system into the first working mode, in which the first heat exchanger is circulated with the first fluid and the second heat exchanger is circulated with the second fluid.

[0074] S200: After a first predetermined time, control the valve group to switch to the second operating mode. In this mode, the second heat exchanger circulates the first fluid, and the first heat exchanger circulates the second fluid.

[0075] S300: After the second predetermined time, control the valve group to switch back to the first working mode again, and repeat this cycle.

[0076] For details, please refer to the previous text; they will not be repeated here.

[0077] In one embodiment, taking a circular tube straight finned dual-channel heat exchanger as an example, the operation control method further includes a step of optimizing the first predetermined time or the second predetermined time, the optimization step including:

[0078] S400. Use finite element simulation software to perform geometric modeling of the circular tube straight finned dual-channel heat exchanger, establish the three-dimensional geometric model of the dual-channel heat exchanger and generate the mesh.

[0079] S500. Based on the operating conditions corresponding to the aforementioned operation control method, set simulation boundary conditions and solve them.

[0080] Specifically, the inlet velocities of air, the first fluid (cold fluid), and the second fluid (hot fluid) were set to 3 m / s, the outlet pressure was 0 Pa, the cold fluid temperature was 29 °C, the hot fluid temperature was 34 °C, and the air temperature was 32 °C. Based on this, the transient heat transfer process was simulated.

[0081] S600. Based on the temperature field, velocity field and pressure field data obtained from the solution, analyze and determine the heat exchange effect of the dual-channel heat exchanger.

[0082] Taking the first operating mode running for 120 seconds as an example, the pressure distribution, temperature distribution, and air velocity distribution inside the circular tube straight finned dual-channel heat exchanger are as follows: Figure 8 , Figure 9 and Figure 10 As shown in the diagram, the temperature distribution is uniform after 120 seconds of operation in the first working mode, thus achieving the purpose of air cooling.

[0083] S700. Based on the analysis results, the configuration and predetermined time of the dual-channel heat exchanger are optimized.

[0084] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A multi-mode dual-channel heat exchange system, characterized in that, include: The first heat exchanger and the second heat exchanger have the same structure, and each has a first flow channel and a second flow channel that are isolated from each other. A first fluid source is used to provide the first fluid; A second fluid source is provided to supply a second fluid, wherein the first fluid and the second fluid have different temperatures and the two fluids have the same or different physicochemical properties. A fluid piping network connects the fluid source to the flow path of the heat exchanger via valve assemblies; The control system periodically switches the valve group, causing the system to alternate between a first operating mode and a second operating mode; Wherein: in the first working mode, the first fluid source is connected to the first flow channel of the first heat exchanger, and the second fluid source is connected to the second flow channel of the second heat exchanger; In the second operating mode, the first fluid source is connected to the first flow channel of the second heat exchanger, and the second fluid source is connected to the second flow channel of the first heat exchanger. In the first or second operating mode, a single heat exchanger circulates only the first fluid or the second fluid.

2. The multi-mode dual-channel heat exchange system according to claim 1, characterized in that, The first fluid is a cold fluid with a temperature lower than the ambient temperature, and the second fluid is a hot fluid with a temperature higher than the ambient temperature; or, the first fluid is a hot fluid with a temperature higher than the ambient temperature, and the second fluid is a cold fluid with a temperature lower than the ambient temperature.

3. The multi-mode dual-channel heat exchange system according to claim 2, characterized in that, This also includes wind turbine units; In the first operating mode, the fan unit provides the air to be treated to the first heat exchanger and the regenerated air to the second heat exchanger; In the second operating mode, the fan unit provides the air flow to be treated to the second heat exchanger and the regenerated air flow to the first heat exchanger.

4. The multi-mode dual-channel heat exchange system according to claim 3, characterized in that, The first flow channel and the second flow channel are sloped along the flow direction.

5. The multi-mode dual-channel heat exchange system according to any one of claims 1 to 4, characterized in that, The control system is also configured to execute an auxiliary operating mode in which the control switching valve group causes the fluids supplied by the first fluid source and the second fluid source to flow simultaneously through a designated heat exchanger.

6. A dual-channel heat exchanger for use in any one of the heat exchange systems of claims 1-5, characterized in that, include: Casing (100); A first tube bundle (110) and a second tube bundle (120) are disposed in the housing (100) in a mutually isolated manner, the first tube bundle (110) forming a first flow channel and the second tube bundle (120) forming a second flow channel; Both the first flow channel and the second flow channel have a slope along the flow direction.

7. The dual-channel heat exchanger of the heat exchange system according to claim 6, characterized in that, It also includes multiple heat exchange fins (130), which are fixedly connected to the first tube bundle (110) and the second tube bundle (120), and gaps are formed between the heat exchange fins to allow air to pass through.

8. The dual-channel heat exchanger of the heat exchange system according to claim 7, characterized in that, The surface of the heat exchange fins (130) is coated with a solid desiccant coating.

9. A method for operating and controlling a heat exchange system as described in any one of claims 1 to 5, characterized in that, Includes the following steps: The control switching valve group enables the system to enter the first working mode, in which the first heat exchanger is circulated with the first fluid and the second heat exchanger is circulated with the second fluid. After a first predetermined time, the valve group is controlled to switch to a second operating mode, wherein the second heat exchanger is circulated with a first fluid, and the first heat exchanger is circulated with a second fluid; After a second predetermined time, the valve group is controlled to switch back to the first working mode, and this cycle is repeated.

10. The operation control method for the heat exchange system according to claim 9, characterized in that, It also includes a step of optimizing the first predetermined time or the second predetermined time, the optimization step including: Establish a three-dimensional geometric model of the dual-channel heat exchanger; Based on the operating conditions corresponding to the aforementioned operation control method, simulation boundary conditions are set and solved; Based on the temperature field, velocity field, and pressure field data obtained from the solution, the heat exchange effect of the dual-channel heat exchanger is analyzed and determined. Based on the analysis results, the configuration and predetermined time of the dual-channel heat exchanger were optimized.

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