Heat exchangers, flow path control methods for heat exchangers, readable storage media, and air conditioners

Abstract

The present invention discloses a heat exchanger, a flow path control method for the heat exchanger, a readable storage medium, and an air conditioner. The heat exchanger includes a liquid collecting pipe, a gas collecting pipe, a gas-liquid separator, a separable module, a variable flow path module, and a fourth control valve. The gas end of the gas-liquid separator is connected to the gas collecting pipe through a first pipeline; both ends of the separable module are respectively connected to a liquid end of the gas-liquid separator and the liquid collecting pipe through a second pipeline and a third pipeline; both ends of the first heat exchange tube group in the variable flow path module are respectively connected to the gas collecting pipe and another liquid end through a fourth pipeline and a fifth pipeline; both ends of the second heat exchange tube group are connected to the gas collecting pipe and another liquid end through a sixth pipeline and a seventh pipeline. One end of a third control valve is connected to one end of a first control valve away from the gas collecting pipe, and the other end is connected to one end of a second control valve away from another liquid end; the fourth control valve is provided on the first pipeline. The technical solution of the present invention can switch different numbers of heat exchange flow paths between different operating modes and improve the heat exchange effect.

Description

Technical Field

[0001] This invention relates to the field of heat exchanger technology, and particularly to a heat exchanger, a flow path control method for the heat exchanger, a readable storage medium, and an air conditioner using the heat exchanger. Background Technology

[0002] For existing heat pump air conditioner heat exchangers, the flow path is the same under various operating conditions, including cooling, heating, and different operating frequencies. However, numerous studies have shown that the optimal flow path for indoor and outdoor heat exchangers differs under these conditions. When the heat exchanger acts as a condenser, its pressure loss is relatively small, requiring fewer branch paths to increase refrigerant velocity and thus the heat transfer coefficient. When the heat exchanger acts as an evaporator, during medium- to high-frequency operation, the decrease in the logarithmic mean temperature difference caused by pressure loss has a dominant impact on heat transfer, compared to the effect of flow velocity on the heat transfer coefficient. In this case, a larger number of branch paths is needed to increase heat transfer. Consequently, it becomes impossible to adjust the heat exchanger flow path based on actual operating conditions for the same heat exchanger.

[0003] Existing technologies also include air conditioning heat exchangers that can change the flow path during evaporation / condensation modes. However, existing heat exchangers are highly specific, have low modularity, and are difficult to adapt to large-capacity air conditioners with large heat exchange areas. When the flow path is changed, it is limited to adding or removing a few flow paths, with few ways to change the flow path. During the evaporation process, the gaseous refrigerant still degrades the evaporation heat transfer coefficient, which limits the performance of heat exchangers and heat pumps (hot air blowers, heat pump water heaters). Summary of the Invention

[0004] The main objective of this invention is to propose a heat exchanger that aims to improve the problem of deterioration of the heat transfer coefficient by gaseous refrigerants and enhance the heat exchange effect.

[0005] To achieve the above objectives, the heat exchanger proposed in this invention includes a liquid collecting pipe;

[0006] Gas collection tube;

[0007] A gas-liquid separator, comprising two liquid ends and one gas end, wherein the gas end is connected to the gas collecting pipe via a first pipeline;

[0008] A separable module, one end of which is connected to the liquid end of the gas-liquid separator via a second pipeline, and the other end of which is connected to the liquid collection pipe via a third pipeline;

[0009] A variable flow path module, comprising: a first heat exchange tube group, a second heat exchange tube group, and a control valve assembly, wherein the control valve assembly comprises a first control valve, a second control valve, and a third control valve;

[0010] One end of the first heat exchange tube assembly is connected to the gas collecting pipe through the fourth pipe, and the other end is connected to the other liquid end through the fifth pipe; one end of the second heat exchange tube assembly is connected to the gas collecting pipe through the sixth pipe, and the other end is connected to the other liquid end through the seventh pipe.

[0011] The first control valve is located in the fifth pipeline, and the second control valve is located in the sixth pipeline; the third control valve has a first end and a second end that are interconnected, the first end being connected to the end of the first control valve away from the gas collecting pipe, and the second end being connected to the end of the second control valve away from the other liquid end; and

[0012] A fourth control valve is located on the first pipeline.

[0013] Optionally, the separable module includes two first separation flow paths, which are connected in parallel.

[0014] Optionally, the separable module further includes a second separation flow path, wherein the two first separation flow paths are connected in parallel and then connected in series with the second separation flow path.

[0015] Optionally, the single-flow path length of the separable module is 0.15 to 0.55 times the single-flow path length of the variable-flow path module.

[0016] Optionally, the first control valve is a first check valve, and the conduction direction of the first check valve is from the other liquid end to the first heat exchange tube assembly.

[0017] And / or, the second control valve is a second check valve, and the conduction direction of the second check valve is from the second heat exchange tube group to the gas collecting pipe.

[0018] Optionally, both the first heat exchange tube group and the second heat exchange tube group are provided with at least two, with at least two first heat exchange tube groups and at least two second heat exchange tube groups connected in parallel;

[0019] The third control valve is provided such that the end of each of the first heat exchange tube groups near the liquid collection pipe is connected to the first end; and the end of each of the second heat exchange tube groups near the gas collection pipe is connected to the second end.

[0020] Optionally, the fourth control valve is a third check valve, and the conduction direction of the third check valve is from the gas end to the gas collecting pipe;

[0021] Alternatively, the fourth control valve may be an electronic expansion valve or a capillary.

[0022] The present invention also proposes a flow path control method based on the above-mentioned heat exchanger, wherein the heat exchanger is applied in a refrigeration system, and the flow path control method includes:

[0023] Obtain the operating mode of the heat exchanger and the load mode of the refrigeration system;

[0024] When the operating mode is evaporation mode, the fourth control valve is turned on.

[0025] When the operating mode is condensation mode, the fourth control valve is closed.

[0026] Based on the obtained load mode, the first control valve is controlled to have the same opening and closing state as the second control valve, and the third control valve is controlled to have the opposite opening and closing state as the first control valve.

[0027] Optionally, the step of obtaining the operating mode of the heat exchanger and the load mode of the refrigeration system includes:

[0028] To determine the direction of refrigerant flow;

[0029] When the flow direction of the refrigerant is detected as flowing from the liquid collection pipe to the gas collection pipe, the heat exchanger is determined to be in evaporation mode.

[0030] When the flow direction of the refrigerant is detected as flowing from the gas collecting pipe to the liquid collecting pipe, the heat exchanger is determined to be in condensation mode.

[0031] Optionally, the step of controlling the first control valve and the second control valve to have the same opening and closing state, and controlling the third control valve to have the opposite opening and closing state to the first control valve, according to the acquired load mode, specifically includes:

[0032] When the load mode is the first load mode, the variable flow path module adopts the full flow path mode, that is, it controls the first control valve and the second control valve to be turned on, and controls the third control valve to be turned off;

[0033] When the load mode is the second load mode, the variable flow path module adopts a half flow path mode, that is, it controls the first control valve and the second control valve to close and controls the third control valve to open, wherein the first load is greater than the second load.

[0034] Optionally, when the fourth control valve is an electronic expansion valve, the flow path control method for the heat exchanger further includes:

[0035] Obtain the target operating frequency Fr of the refrigeration system;

[0036] Determine the magnitude of the target operating frequency Fr and the third preset value c, where c = l * (Fmax + Fmin), l ranges from 0.45 to 0.75, Fmax is the maximum operating frequency of the compressor, and Fmin is the minimum operating frequency of the compressor;

[0037] Based on the judgment result, the initial opening degree and holding time of the electronic expansion valve are obtained, and initialization control is performed.

[0038] Optionally, the step of obtaining the initial opening degree and holding time of the electronic expansion valve based on the judgment result and performing initialization control specifically includes:

[0039] If Fr≤c, then the initial opening of the electronic expansion valve is set to the first opening A, and the holding time is t1;

[0040] If Fr > c, then the initial opening of the electronic expansion valve is set to the second opening B, and the holding time is t2;

[0041] Where A is less than B, the range of the first opening A is 20P to 100P, the range of the second opening B is 50P to 150P; the range of t1 is 2min to 15min, and the range of t2 is 1min to 15min.

[0042] The present invention also proposes a readable storage medium storing a flow path control program for a heat exchanger, wherein when the flow path control program for the heat exchanger is executed by a processor, the flow path control program for the heat exchanger implements the steps of the above-described flow path control method for the heat exchanger.

[0043] The present invention also proposes an air conditioner comprising any of the heat exchangers described above.

[0044] Optionally, the air conditioner includes an outdoor unit, and the heat exchanger is disposed inside the outdoor unit.

[0045] In this invention, when the heat exchanger is used as an evaporator, the liquid phase change working fluid enters from the liquid collection pipe. It first undergoes preliminary evaporation through a separable module, then enters a gas-liquid separator via the liquid end for gas-liquid separation. The separated gas enters the first pipeline via the gas end, and after passing through the fourth control valve, it enters the gas collection pipe. The liquid portion enters the variable flow path module via another liquid end. This allows for timely separation of the gas portion after preliminary heat exchange, resulting in a higher heat transfer coefficient for the subsequent liquid portion and effectively enhancing the heat exchanger's heating effect. After entering the variable flow path module, the fluid splits into two paths. By opening the first control valve, it flows along the fifth and seventh pipelines to the first and second heat exchange tube groups, respectively. After heat exchange in the first heat exchange tube group, the gaseous phase change working fluid flows to the fourth pipeline, and after heat exchange in the second heat exchange tube group, it flows to the sixth pipeline. By opening the second control valve, the phase change working fluid can flow out from both the third and fourth pipelines and converge into the gas collection pipe. In this state, the number of flow paths for the phase change working fluid is the sum of the first and second heat exchanger tube groups, meaning there are more flow paths. This increases the heat exchange capacity in evaporation mode, further achieving a better heat exchange effect. When the heat exchanger is used as a condenser, the gaseous phase change working fluid enters from the gas collecting pipe. By opening the third control valve and closing the first and second control valves, the first and second heat exchanger tube groups are connected in series. The phase change working fluid flowing out of the gas collecting pipe flows to the liquid collecting pipe after heat exchange with the first and second heat exchanger tube groups. This reduces the number of flow paths in condensation mode, increases the flow rate of the phase change working fluid, and thus increases the heat transfer coefficient, also achieving a better heat exchange effect. Attached Figure Description

[0046] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0047] Figure 1 This is a schematic diagram of the structure of the heat exchanger of the present invention when it is used as an evaporator in one embodiment;

[0048] Figure 2 for Figure 1 The diagram shows the structure of the heat exchanger when it is used as a condenser.

[0049] Figure 3 for Figure 1 The diagram shows the flow path of a heat exchanger used as an evaporator in an air conditioner.

[0050] Figure 4 for Figure 1The diagram shows the flow path of a heat exchanger used as a condenser in an air conditioner.

[0051] Figure 5 This is a schematic diagram of another embodiment of the heat exchanger of the present invention;

[0052] Figure 6 This is a schematic diagram of another embodiment of the heat exchanger of the present invention.

[0053] Explanation of icon numbers:

[0054] label name label name 100 Collection tube 650 Fifth pipeline 200 Gas collection tube 660 Sixth pipeline 300 First heat exchanger tube assembly 670 Seventh pipeline 400 Second heat exchanger tube assembly 700 gas-liquid separator 510 First control valve 701 Gas end 520 Second control valve 702，703 Liquid end 530 Third control valve 800 Detachable module 540 Fourth control valve 801 First separation flow path 610 First pipeline 802 Second separation flow path 620 Second pipeline 900 Common heat exchanger tube assemblies 630 Third pipeline 2000 compressor 640 Fourth pipeline

[0055] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0056] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0057] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0058] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0059] This invention proposes a heat exchanger.

[0060] In embodiments of the present invention, such as Figure 1 and Figure 2As shown, the heat exchanger includes a liquid collection pipe 100, a gas collection pipe 200, a gas-liquid separator 700, a separable module 800, a variable flow path module, and a fourth control valve 540. The gas-liquid separator 700 includes two liquid ends (702, 703) and a gas end 701. The gas end 701 is connected to the gas collection pipe 200 through a first pipe 610.

[0061] One end of the separable module 800 is connected to the liquid end 702 of the gas-liquid separator 700 through the second pipe 620, and the other end is connected to the liquid collection pipe 100 through the third pipe 630.

[0062] The variable flow path module includes: a first heat exchange tube group 300, a second heat exchange tube group 400, and a control valve assembly. The control valve assembly includes a first control valve 510, a second control valve 520, and a third control valve 530. One end of the first heat exchange tube group 300 is connected to the gas collecting pipe 200 via a fourth pipe 640, and the other end is connected to the other liquid end 703 via a fifth pipe 650. One end of the second heat exchange tube group 400 is connected to the gas collecting pipe 200 via a sixth pipe 660, and the other end is connected to the third liquid end 703 via a fifth pipe 650. The seventh pipe 670 is connected to another liquid end 703; the first control valve 510 is located in the fifth pipe 650, and the second control valve 520 is located in the sixth pipe 660; the third control valve 530 has a first end and a second end that are connected to each other, the first end is connected to the end of the first control valve 510 away from the gas collecting pipe 200, and the second end is connected to the end of the second control valve 520 away from the other liquid end 703; the fourth control valve 540 is located on the first pipe 610.

[0063] Please combine Figure 3 and Figure 4 It should be noted that the phase change working fluid in the heat exchanger of the present invention can flow either from the liquid collecting pipe 100 to the gas collecting pipe 200, or from the gas collecting pipe 200 to the liquid collecting pipe 100. Therefore, the heat exchanger of the present invention can be adapted to air conditioners that have both cooling and heating functions. For example, when the air conditioner is in heating mode, it acts as an evaporator in the outdoor unit; or when the air conditioner is in cooling mode, it acts as a condenser in the outdoor unit. Of course, the heat exchanger can also be used in heat pump systems or other systems that perform cooling or heating, such as commercial, automotive, and drilling industry refrigeration / heat pump devices.

[0064] For the refrigerant evaporation process inside a circular tube, the refrigerant flow pattern, with increasing dryness, is as follows: single-phase liquid flow, bubbly flow, slug flow, annular flow, mist flow, and single-phase gas flow. In the bubbly, slug, and annular flow regions, as the refrigerant dryness increases, the heat transfer coefficient on the inner surface of the tube increases due to the increase in the average flow velocity inside the tube. However, in the mist flow region, due to excessive refrigerant dryness, the liquid film on the inner surface of the tube is destroyed, leading to deteriorated heat transfer and a sharp decrease in the heat transfer coefficient, which greatly affects the heat exchange performance of the evaporator. Applying gas bypass evaporation technology can effectively reduce the area of ​​the mist flow region, thereby increasing the effective heat exchange area of ​​the heat exchanger. In the technical solution of this invention, the phase separation evaporator technology can reduce the average flow velocity of the refrigerant, thereby reducing the refrigerant-side resistance loss and improving the overall performance of the heat exchanger. Therefore, when the heat exchanger is in evaporation mode, a portion of the phase change refrigerant can be evaporated first through the separable module 800. Then, at the point where heat exchange efficiency deteriorates, the gaseous refrigerant after heat exchange is separated by the gas-liquid separator 700. The remaining liquid refrigerant continues to evaporate, thereby improving the problem of deteriorated evaporation heat transfer coefficient of the gaseous refrigerant and improving heat exchange effect and efficiency. That is, during heating, gaseous refrigerant can be extracted to improve the evaporation heat transfer coefficient, thereby improving the overall heat exchange efficiency. At the same time, the heat exchanger can achieve the effect of switching different numbers of flow paths when in different operating states. It can be understood that when the heat exchanger is used as an evaporator, compared with the influence of flow velocity on the heat transfer coefficient, the decrease in logarithmic mean temperature difference caused by pressure loss has a dominant impact on the heat exchange capacity. In this case, we would like to use more flow paths to increase the heat exchange capacity.

[0065] Specifically, when the heat exchanger functions as an evaporator, the first control valve 510 and the second control valve 520 are both open, the third control valve 530 is closed, and the fourth control valve 540 is also open. The two ends of the first heat exchange tube assembly 300 are connected to the gas collecting pipe 200 and the gas-liquid separator 700 via the fourth pipe 640 and the fifth pipe 650, respectively. The two ends of the second heat exchange tube assembly 400 are connected to the gas collecting pipe 200 and the gas-liquid separator 700 via the sixth pipe 660 and the seventh pipe 670, respectively. If the liquid level is 00, the phase change working fluid entering from the liquid collection pipe 100 will first pass through the separable module 800. After preliminary evaporation and heat exchange, it will enter the gas-liquid separator 700. The gaseous working fluid will flow from the gas end 701 to the gas collection pipe 200, while the remaining liquid working fluid will flow in two separate streams. One stream will flow sequentially through the fifth pipe 650 (including the first control valve 510) and the first heat exchange tube group 300; the other stream will flow through the seventh pipe 670 and the second heat exchange tube group 400. Then, after simultaneous heat exchange in the first heat exchange tube group 300 and the second heat exchange tube group 400, it will be converted into a gaseous state and will converge into the gas collection pipe 200 via the fourth pipe 640 and the sixth pipe 660 respectively. Therefore, when the heat exchanger is used as an evaporator, the gaseous working fluid after heat exchange can be separated in a timely manner, reducing the deterioration of the heat exchange performance of the liquid working fluid. When the number of the first heat exchanger tube group 300 and the second heat exchanger tube group 400 are defined as A and B respectively, the phase change working fluid can flow through (A+B) flow paths simultaneously in the variable flow path module.

[0066] When the heat exchanger is used as a condenser, the flow rate of the phase change working fluid has a dominant effect on the heat transfer. In this case, we want to use fewer flow paths to increase the heat transfer coefficient. Specifically, by shutting off the first control valve 510 and the second control valve 520, and also shutting off the fourth control valve 540, the high-temperature and high-pressure gaseous phase change working fluid entering from the gas collecting pipe 200 will only flow into the first heat exchange tube group 300 through the fourth pipe 640 for heat exchange, so that the phase change working fluid condenses into a liquid state. Next, since the first control valve 510 on the fifth pipe 650, which is connected to the first heat exchanger tube group 300, is in the closed state, the phase change working fluid will not flow from the fifth pipe 650 to the gas-liquid separator 700. However, by opening the third control valve 530, the phase change working fluid after heat exchange in the first heat exchanger tube group 300 will enter the second heat exchanger tube group 400 for further heat exchange into more liquid phase change working fluid, and then flow from the second heat exchanger tube group 400 to the seventh pipe 670, and from the seventh pipe 670 to the gas-liquid separator 700. Therefore, when the heat exchanger is used as a condenser, and the number of the first heat exchanger tube group 300 and the second heat exchanger tube group 400 are defined as A and B respectively, the phase change working fluid can first flow through the A main heat exchange path simultaneously, and then flow through the B subcooling path simultaneously. It is understood that the number of the first heat exchange tube group 300 and the second heat exchange tube group 400 can be the same. When the number of the first heat exchange tube group 300 and the second heat exchange tube group 400 is the same, the number of heat exchange flow paths of the heat exchanger in the technical solution of the present invention when it is used as an evaporator is twice the number of heat exchange flow paths of the heat exchanger when it is used as a condenser.

[0067] This invention achieves the flow of phase change working fluid with different numbers of flow paths under different operating modes simply by adding three control valves to the heat exchanger. By controlling the opening and closing of these three valves, multiple flow paths are provided when the heat exchanger is operating as an evaporator, thereby increasing heat exchange capacity and improving the heat exchange effect during evaporation. Furthermore, the inclusion of the separable module 800 and the gas-liquid separator 700 further mitigates the problem of the gaseous working fluid deteriorating the evaporation heat transfer coefficient of the liquid working fluid, improving heat exchange efficiency. Conversely, when the heat exchanger is operating as a condenser, fewer flow paths are provided, thereby increasing the flow rate of the phase change working fluid and improving the heat exchange effect during condensation. Thus, the heat exchanger can adapt to different operating conditions and maintain good heat exchange performance under all conditions.

[0068] Furthermore, the first heat exchange tube group 300 and the second heat exchange tube group 400 in the heat exchanger of the present invention are both modular, which can adapt to large-capacity air conditioners with large heat exchange areas, as well as small-capacity air conditioners with small heat exchange areas, or air conditioners that focus on dehumidification, etc. That is, when a large heat exchange area is required under high-load mode, the number of the first heat exchange tube group 300 and / or the second heat exchange tube group 400 can be increased in parallel without adding other control valve groups to achieve the effect of different heat exchange flow paths in different operating modes. Therefore, the heat exchanger of the present invention is modular, highly versatile, simple to control, low in cost, adaptable to various different operating states, and the number of the first heat exchange tube group 300 and / or the second heat exchange tube group 400 can be flexibly increased.

[0069] In this invention, when the heat exchanger is used as an evaporator, the liquid phase change working fluid enters from the liquid collection pipe 100. It first undergoes preliminary evaporation through the separable module 800, and then enters the gas-liquid separator 700 through the liquid end 702 for gas-liquid separation. The separated gas enters the first pipeline 610 through the gas end 701, and then enters the gas collection pipe 200 after passing through the fourth control valve 540. The liquid part enters the variable flow path module through another liquid end 703. In this way, the gas part can be separated out in time after the preliminary heat exchange, so that the heat exchange coefficient of the subsequent liquid part is higher, effectively enhancing the heating effect of the heat exchanger. After entering the variable flow path module, the flow splits into two paths. By activating the first control valve 510, the fluid flows along the fifth pipe 650 and the seventh pipe 670 to the first heat exchange tube group 300 and the second heat exchange tube group 400, respectively. After heat exchange in the first heat exchange tube group 300, the gaseous phase change working fluid flows to the fourth pipe 640, and after heat exchange in the second heat exchange tube group 400, it flows to the sixth pipe 660. By activating the second control valve 520, the phase change working fluid can flow out from both the third pipe 630 and the fourth pipe 640, and converge into the gas collecting pipe 200. In this state, the number of flow paths for the phase change working fluid is the sum of the number of flow paths in the first heat exchange tube group 300 and the second heat exchange tube group 400, i.e., a larger number of flow paths, thereby increasing the heat exchange capacity in evaporation mode and further achieving a better heat exchange effect. When the heat exchanger is used as a condenser, the gaseous phase change working fluid enters from the gas collecting pipe 200. By opening the third control valve 530 and closing the first control valve 510 and the second control valve 520, the first heat exchange tube group 300 and the second heat exchange tube group 400 are connected in series. The phase change working fluid flowing out of the gas collecting pipe 200 flows to the liquid collecting pipe 100 after heat exchange with the first heat exchange tube group 300 and the second heat exchange tube group 400. This reduces the number of flow paths and increases the flow rate of the phase change working fluid in condensation mode, thereby increasing the heat transfer coefficient and achieving a better heat exchange effect.

[0070] Please continue to refer to Figure 1 and Figure 2Optionally, the separable module 800 includes two first separation flow paths 801, which are arranged in parallel.

[0071] In this embodiment, the phase separation evaporator technology reduces the average flow velocity of the refrigerant within the tubes, thereby reducing refrigerant-side resistance loss and improving the overall performance of the heat exchanger. Specifically, a separable module 800 is provided at the end of the liquid collection pipe 100 away from the first heat exchange tube group 300 and the second heat exchange tube group 400. The separable module 800 includes two parallel first separation flow paths 801. When the heat exchanger is used as an evaporator, the working fluid flow velocity is reduced by increasing the flow paths. After passing through the two first separation flow paths 801, the phase change working fluid enters the gas-liquid separator 700, allowing some of the evaporated gas to be separated and enter the gas collection pipe 200 through the fourth control valve 540, while the remaining liquid continues to enter the variable flow path module for further evaporation. When the heat exchanger is used as a condenser, the phase change working fluid, after heat exchange through the first heat exchange tube group 300 and the second heat exchange tube group 400, can undergo further heat exchange through the two first separation flow paths 801 before being recooled, further improving heat exchange efficiency.

[0072] Of course, in other embodiments, two or more first separation flow paths 801 may be set in parallel.

[0073] Optionally, the separable module 800 further includes a second separation flow path 802, wherein the two first separation flow paths 801 are connected in parallel and then connected in series with the second separation flow path 802.

[0074] To further improve heat exchange efficiency, in this embodiment, after the phase change working fluid passes through two first separation flow paths 801, it continues to pass through a second separation flow path 802 for heat exchange, i.e., it undergoes subcooling treatment, and then enters the liquid collection pipe 100. This can further improve heat exchange efficiency, enhance the heat exchange effect, and ensure that the phase change working fluid receives sufficient heat exchange, thereby improving heat exchange efficiency.

[0075] Optionally, the single-flow path length of the separable module 800 is 0.15 to 0.55 times the single-flow path length of the variable flow path module.

[0076] In this embodiment, the separable module 800, serving as a module for improving the heat transfer coefficient at the deterioration point of the gaseous working fluid, should not have an excessively long single-flow path length, exceeding that of the variable flow path module, which serves as the primary heat exchanger. Conversely, its single-flow path length should not be too short either, otherwise it will fail to reduce the flow rate and improve the heat transfer coefficient. Therefore, the single-flow path length of the separable module 800 is 0.15 to 0.55 times that of the variable flow path module, for example, 0.15, 0.2, 0.3, 0.4, or 0.5 times, to cooperate with the variable flow path module and achieve better heat exchange performance. Here, the optional single-flow path length of the separable module 800 is 0.5 times that of the variable flow path module.

[0077] Of course, based on the above reasons, the number of flow paths in the separable module 800 should not be too large. The total number of flow paths in the separable module 800 is less than the maximum number of flow paths in the variable flow path module. For example, the separable module 800 includes two first separation flow paths 801, which is less than the maximum number of flow paths of 4 when the variable flow path module is equipped with two first heat exchange tube groups 300 and two second heat exchange tube groups 400.

[0078] Please refer to this again. Figure 1 and Figure 2 Optionally, the first control valve 510 is a first check valve, and the conduction direction of the first check valve is from the other liquid end 703 to the first heat exchange tube group 300.

[0079] And / or, the second control valve 520 is a second check valve, and the conduction direction of the second check valve is from the second heat exchange tube group 400 to the gas collecting pipe 200.

[0080] Understandably, a one-way valve can only be open in one flow direction and cannot be open in the opposite direction. Therefore, by setting the first control valve 510 as a one-way valve, the procedure of setting up other control units to control the opening and closing of the first control valve 510 can be eliminated. Specifically, the opening direction of the first one-way valve is limited to the direction in which the phase change working fluid flows from the gas-liquid separator 700 to the first heat exchange tube group 300, but not to the direction in which the phase change working fluid flows from the first heat exchange tube group 300 to the gas-liquid separator 700. Similarly, the opening direction of the second one-way valve is also limited to the direction in which the phase change working fluid flows from the second heat exchange tube group 400 to the gas collecting pipe 200, but not to the direction in which the phase change working fluid flows from the gas collecting pipe 200 to the second heat exchange tube group 400.

[0081] Taking the example of the first control valve 510 being located in the fifth pipeline 650 and the second control valve 520 being located in the sixth pipeline 660, this configuration allows the phase change working fluid to flow in the fifth pipeline 650 when the heat exchanger is used as an evaporator. The second one-way valve located in the sixth pipeline 660 also allows the phase change working fluid to flow in the sixth pipeline 660. This ensures that the phase change working fluid can have at least one flow path from the gas-liquid separator 700 through the fifth pipeline 650, the first heat exchange tube group 300, the fourth pipeline 640 to the gas collecting pipe 200, and another flow path from the liquid collecting pipe 100 through the seventh pipeline 670, the second heat exchange tube group 400, the sixth pipeline 660 to the gas collecting pipe 200.

[0082] When the heat exchanger is used as a condenser, the phase change working fluid flows out from the gas collecting pipe 200 and passes through the fourth pipe 640, the first heat exchange tube group 300, and the third control valve 530 before entering the second heat exchange tube group 400. It is understood that after the phase change working fluid exchanges heat in the first heat exchange tube group 300, its pressure upon exiting is lower than its pressure upon entering the first heat exchange tube group 300, and therefore also lower than the pressure at the end of the second check valve near the gas collecting pipe 200. Therefore, even if the second check valve, after passing through the third control valve 530, enters the end of the second heat exchange tube group 400 near the gas collecting pipe 200, it will not flow back into the gas collecting pipe 200 through the second check valve. Instead, it continues to exchange heat through the second heat exchange tube group 400 and enters the seventh pipe 670, subsequently entering the gas-liquid separator 700.

[0083] Of course, in other embodiments, the first control valve 510 and / or the second control valve 520 may also be solenoid valves. When the first control valve 510 and / or the second control valve 520 are solenoid valves, the first control valve 510 and the second control valve 520 can be controlled to be in the open state when the heat exchanger is used as an evaporator, and the first control valve 510 and the second control valve 520 can be controlled to be in the closed state when the heat exchanger is used as a condenser.

[0084] When the first control valve 510 is located in the fourth pipeline 640 and the second control valve 520 is located in the seventh pipeline 670, since the first end of the third control valve 530 is connected to the end of the first control valve 510 away from the gas-liquid separator 700 and the second end is connected to the end of the second control valve 520 away from the gas collecting pipe 200, when the heat exchanger is used as a condenser, the phase change working fluid flowing out of the gas collecting pipe 200 will flow through the sixth pipeline 660 to the second heat exchange tube group 400. After heat exchange in the second heat exchange tube group 400, it will enter the first heat exchange tube group 300 through the third control valve 530 for further heat exchange, and then flow into the gas-liquid separator 700 through the seventh pipeline 670.

[0085] Here, the third control valve 530 can be selected as a solenoid valve. In this embodiment, the third control valve 530 is limited to opening only when the heat exchanger is used as a condenser, and not opening when the heat exchanger is used as an evaporator. In this embodiment, when the first control valve 510 is located in the fourth pipeline 640 and the second control valve 520 is located in the sixth pipeline 660, since the first end of the third control valve 530 is connected to the end of the first control valve 510 away from the gas-liquid separator 700, and the second end is connected to the end of the second control valve 520 away from the gas collecting pipe 200, when the heat exchanger is used as a condenser, the phase change working fluid flowing out of the gas collecting pipe 200 will flow through the fourth pipeline 640 to the first heat exchange tube group 300. After heat exchange in the first heat exchange tube group 300, it will enter the second heat exchange tube group 400 through the third control valve 530 for further heat exchange, and then flow into the gas-liquid separator 700 through the seventh pipeline 670.

[0086] Optionally, at least two of the first heat exchange tube group 300 and the second heat exchange tube group 400 are provided, with at least two of the first heat exchange tube groups 300 connected in parallel and at least two of the second heat exchange tube groups 400 connected in parallel;

[0087] The third control valve 530 is provided such that the end of each first heat exchange tube group 300 near the liquid collection pipe 100 is connected to the first end; and the end of each second heat exchange tube group 400 near the gas collection pipe 200 is connected to the second end.

[0088] By setting at least two first heat exchanger tube groups 300, and at least two first heat exchanger tube groups 300 connected in parallel, the number of flow paths when the heat exchanger is used as an evaporator can be increased, and the flow path length when the heat exchanger is used as a condenser can also be increased. It is understood that the number of first heat exchanger tube groups 300 and the number of second heat exchanger tube groups 400 can be the same or different. When the number of first heat exchanger tube groups 300 and second heat exchanger tube groups 400 is the same and both are N, the number of flow paths when the heat exchanger is used as an evaporator is 2N, and the number of flow paths when the heat exchanger is used as a condenser is N. Here, N is an integer, such as 1, 2, 3, 4, or 5. In this case, the separable module 800 includes two first separation flow paths 801, which is less than the maximum number of flow paths in the variable flow path module.

[0089] By setting a third control valve 530, the series and parallel operation of the first heat exchanger tube group 300 and the second heat exchanger tube group 400 can be controlled simply by opening and closing this third control valve 530, which is simple and convenient and reduces the setup of the control program. Specifically, when the third control valve 530 is opened, the module consisting of all parallel first heat exchanger tube groups 300 and the module consisting of all parallel second heat exchanger tube groups 400 can be connected in series, thereby reducing the number of flow paths for the phase change working fluid, which can be used when the heat exchanger is used as a condenser. When the third control valve 530 is closed, all first heat exchanger tube groups 300 and all second heat exchanger tube groups 400 can be connected in parallel, thereby increasing the number of flow paths for the phase change working fluid, which can be used when the heat exchanger is used as an evaporator.

[0090] Of course, in other embodiments, at least two third control valves 530 may be provided. Each third control valve 530 is connected between a first heat exchange tube group 300 and a second heat exchange tube group 400, and when the heat exchanger is used as a condenser, the first heat exchange tube group 300 and the second heat exchange tube group 400 are connected in series. Each third control valve 530 controls a module composed of a first heat exchange tube group 300 and a second heat exchange tube group 400, thereby making the control of the number of flow paths of the entire heat exchanger more flexible, and also making the path of the phase change working fluid from the first heat exchange tube group 300 to the second heat exchange tube group 400 (or from the second heat exchange tube group 400 to the first heat exchange tube group 300) shorter. It can also avoid the situation where the entire heat exchanger cannot work when one of the third control valves 530 is damaged.

[0091] Please combine Figures 3 to 5 Optionally, the fourth control valve 540 is a third check valve, and the conduction direction of the third check valve is from the gas end 701 to the gas collecting pipe 200.

[0092] Alternatively, the fourth control valve 540 may be an electronic expansion valve or a capillary.

[0093] Combination Figure 3In this embodiment, the fourth control valve 540 is a third check valve, which can only be opened in one flow direction and cannot be opened in the opposite direction. Therefore, by setting the fourth control valve 540 as a check valve, the procedure of setting other control units to control the opening and closing of the fourth control valve 540 can be eliminated. When the heat exchanger is used as an evaporator, the third check valve can be opened, so that the gas in the gas-liquid separator 700 can enter the gas collecting pipe 200 through the third check valve and the first pipeline 610. Of course, when the heat exchanger is used as a condenser, the third check valve is not open. At this time, the second control valve 520 is also not open. The phase change working fluid entering through the gas collecting pipe 200 can only flow to the fourth pipe 640 and enter the first heat exchange tube group 300. Moreover, when the phase change working fluid enters the gas-liquid separator 700 after passing through the variable flow path module, the pressure at the end of the third check valve near the gas-liquid separator 700 is lower than that at the end near the gas collecting pipe 200. Therefore, the gas-liquid separator 700 does not work, and all of them enter the separable module 800 from the liquid end 702 at the lower end for recooling or subcooling, further improving the heat exchange effect.

[0094] Please refer to Figure 5 In other embodiments, the fourth control valve 540 can also be an electronic expansion valve or a capillary tube. When the heat exchanger functions as an evaporator, the electronic expansion valve is activated and adjusted to a suitable opening degree, allowing the gaseous working fluid separated from the gas-liquid separator 700 to undergo appropriate pressure reduction before entering the gas collecting pipe 200 and then returning to the compressor 2000 for intake. When the heat exchanger functions as a condenser, the electronic expansion valve opening degree is set to zero. That is, the gas collecting pipe 200 does not enter the gas-liquid separator 700 through the first pipe 610, but instead undergoes heat exchange through the variable flow path module before flowing to the gas-liquid separator 700. At this time, the pressure of the phase change working fluid decreases after heat exchange, becoming less than the working fluid pressure exiting the gas collecting pipe 200. Therefore, it cannot pass through the electronic expansion valve for direct recooling or subcooling before entering the liquid collecting pipe 100.

[0095] Furthermore, such as Figure 6 As shown, based on the scheme that the first control valve 510 is located in the fifth pipeline 650 and the second control valve 520 is located in the sixth pipeline 660, in this embodiment, the heat exchanger also includes a common heat exchange tube assembly 900, one end of which is connected to the fourth pipeline 640 and the other end is connected to the seventh pipeline 670.

[0096] By connecting one end of the commonly used heat exchanger tube assembly 900 to the fourth pipe 640 and the other end to the seventh pipe 670, the commonly used heat exchanger tube assembly 900 is kept in a normally flowing state and is not affected by the opening and closing of the first control valve 510, the second control valve 520, etc. That is to say, regardless of whether the first control valve 510 and / or the second control valve 520 are in the open or closed state, the commonly used heat exchanger tube assembly 900 can supply the phase change working fluid, and the phase change working fluid can flow from the inlet pipe to the outlet pipe.

[0097] Of course, in another embodiment, when the first control valve 510 is located in the seventh pipeline 670 and the second control valve 520 is located in the fourth pipeline 640, in this embodiment, the heat exchange tube assembly 900 is usually connected to the sixth pipeline 660 at one end and to the fifth pipeline 650 at the other end.

[0098] It is understandable that there can be one, two, or more commonly used heat exchanger tube groups 900. Let M be the number of commonly used heat exchanger tube groups 900, and N be the number of the first heat exchanger tube group 300 and the second heat exchanger tube group 400. Then, when the heat exchanger is used as an evaporator, the number of heat exchanger flow paths through which the phase change working fluid flows is (2N+M); when the heat exchanger is used as a condenser, the number of heat exchanger flow paths through which the phase change working fluid flows is (N+M). The values ​​of N and M can be the same or different, and both N and M are integers, taking values ​​of 1, 2, 3, 4, or 5, etc.

[0099] Optionally, the first heat exchanger tube group 300 can be a double-row heat exchanger tube group or a single-row heat exchanger tube group; and / or, the second heat exchanger tube group 400 can be a double-row heat exchanger tube group or a single-row heat exchanger tube group. Regardless of whether the first heat exchanger tube group 300 is a double-row or single-row heat exchanger tube group, it has two interconnected ports, each a conduit through which the phase change working fluid enters from one port and exits from the other. It is understood that when the first heat exchanger tube group 300 is a double-row heat exchanger tube group, it can be connected via an intermediate conduit through which the outlet of one of the two single-row heat exchanger tube groups is connected to the inlet of the other. Of course, the type of the second heat exchanger tube group 400 can be the same as or different from that of the first heat exchanger tube group 300, and the second heat exchanger tube group 400 can also be a double-row or single-row heat exchanger tube group.

[0100] The present invention also proposes an air conditioner, which includes a heat exchanger. The specific structure of the heat exchanger is as described in the above embodiments. Since the air conditioner adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0101] Furthermore, the air conditioner can be a split-type air conditioner, comprising an indoor unit and an outdoor unit connected by refrigerant pipes. Specifically, the indoor unit contains a first heat exchange module, and the outdoor unit contains a second heat exchange module. The first heat exchange module, the second heat exchange module, and the compressor 2000 are connected by refrigerant pipes to form a circulation loop. The heat exchanger in this invention can be located inside the indoor unit, serving as the first heat exchange module; or the heat exchanger can also be located inside the outdoor unit, serving as the second heat exchange module.

[0102] This invention also proposes a flow path control method based on the above-described heat exchanger. Specific embodiments of the heat exchanger described above can be found in the various examples of the heat exchanger, and will not be repeated here. The heat exchanger is applied in a refrigeration system, and the flow path control method includes:

[0103] Step S1: Obtain the operating mode of the heat exchanger and the load mode of the refrigeration system;

[0104] Step S2: When the operating mode is evaporation mode, control the fourth control valve 540 to be turned on;

[0105] Step S3: When the operating mode is condensation mode, control the fourth control valve 540 to close;

[0106] Step S4: Based on the obtained load mode, control the first control valve 510 and the second control valve 520 to have the same opening and closing state, and control the third control valve 530 to have the opposite opening and closing state to the first control valve 510.

[0107] In this embodiment, since the fourth control valve 540 controls the gas flow in the gas-liquid separator 700, when the heat exchanger is in evaporation mode, timely gas-liquid separation is required. Therefore, the fourth control valve 540 is opened, allowing the gaseous working fluid to enter the gas collecting pipe 200 through the fourth control valve 540. When the heat exchanger is in condensation mode, gas does not need to enter the gas-liquid separator 700 first, so the fourth control valve 540 is closed, allowing the phase change working fluid to undergo heat exchange and condensation through the variable flow path module. Therefore, it is necessary to obtain the operating mode of the heat exchanger to control the fourth control valve 540, thereby improving the heat transfer coefficient.

[0108] Understandably, regardless of whether the heat exchanger functions as an evaporator or a condenser, it has a first load mode and a second load mode, with the first load being greater than the second load. In the first load mode, the heat exchanger requires a larger number of heat exchange flow paths, thereby increasing the heat exchange capacity under higher load conditions and achieving better heat exchange performance. In the second load mode, fewer flow paths are needed, resulting in better flow rates and improved heat exchange performance. Therefore, it is necessary to control the first control valve 510, the second control valve 520, and the third control valve 530 according to the load mode of the refrigeration system to achieve optimal heat exchange performance.

[0109] Specifically, when the first control valve 510 and the second control valve 520 are both in the open state (conducting state), the third control valve 530 is in the closed state (shutdown state). When the first control valve 510 and the second control valve 520 are both in the closed state (shutdown state), the third control valve 530 is in the open state (conducting state). The first control valve 510 can be a one-way valve or a two-way solenoid valve. When the first control valve 510 is a one-way valve, to ensure that the heat exchanger has multiple heat exchange paths when acting as an evaporator and fewer heat exchange paths when acting as a condenser, the conduction direction of the first control valve 510 is the direction of flow from the liquid collecting pipe 100 to the gas collecting pipe 200. Similarly, the second control valve 520 can be a one-way valve or a two-way solenoid valve. When the second control valve 520 is a one-way valve, in order to make the heat exchanger have more heat exchange flow paths when it is used as an evaporator and fewer heat exchange flow paths when it is used as a condenser, the conduction direction of the second one-way valve is the direction of flow from the liquid collection pipe 100 to the gas collection pipe 200.

[0110] The heat exchanger in this invention allows for a variable number of heat exchange flow paths simply by adjusting the opening and closing of the first control valve 510, the second control valve 520, and the third control valve 530. This ensures that the heat exchanger has a corresponding number of heat exchange flow paths under different load modes, resulting in good heat exchange performance in all modes. Furthermore, adjusting the opening and closing of the fourth control valve 540 can mitigate the deterioration of the heat transfer coefficient in evaporation mode. The addition of the separable module 800 further reduces the working fluid velocity, thereby enhancing the heat exchange effect in conjunction with the multi-flow path mode. In other words, gaseous refrigerant can be extracted during heating to increase the evaporative heat transfer coefficient, thus improving the overall heat exchange efficiency. In addition, the first heat exchange tube group 300 and the second heat exchange tube group 400 in this invention are modular, so the number of flow paths can be increased arbitrarily. Furthermore, when increasing or decreasing the number of flow paths, it is possible to achieve this without increasing the number of control valves. This results in a variety of heat exchange flow path variations for the heat exchanger, making control simple and cost-effective.

[0111] Optionally, the step of obtaining the operating mode of the heat exchanger and the load mode of the refrigeration system includes:

[0112] Step S11: Obtain the refrigerant flow direction;

[0113] Step S12: When the flow direction of the refrigerant is detected to be from the liquid collection pipe 100 to the gas collection pipe 200, the heat exchanger is determined to be in evaporation mode.

[0114] Step S13: When the flow direction of the refrigerant is detected to be from the gas collecting pipe 200 to the liquid collecting pipe 100, the heat exchanger is determined to be in condensation mode.

[0115] Understandably, the refrigerant flow direction within the heat exchanger differs depending on its operating mode. By obtaining the refrigerant flow direction, the operating state of the heat exchanger can be indirectly determined, thus providing a signal for the opening or closing status of each control valve. This is simple, convenient, and effectively improves control efficiency. In this embodiment, when the refrigerant flow direction is detected as flowing from the liquid collection pipe 100 to the gas collection pipe 200, the heat exchanger is determined to be in evaporation mode. Based on controlling the fourth control valve 540 to open, the first control valve 510 and the second control valve 520 can be controlled to have the same opening and closing state, and the third control valve 530 can be controlled to be opposite to the first control valve 510.

[0116] When the flow direction of the refrigerant is detected to be from the gas collecting pipe 200 to the liquid collecting pipe 100, and the heat exchanger is determined to be in condenser operation mode, the first control valve 510 and the second control valve 520 can be controlled to open and close in the same way, and the third control valve 530 can be controlled to be in the opposite state to the first control valve 510, based on the control valve 540 being closed.

[0117] In other embodiments, air conditioners that simultaneously provide cooling and heating typically include a four-way valve, which exhibits different states in cooling and heating modes. By monitoring the state of the four-way valve, it is possible to determine whether the air conditioner is in cooling or heating mode, and subsequently send a signal to the heat exchanger to cause it to operate in the appropriate mode, i.e., to switch to evaporation or condensation mode.

[0118] Optionally, the step of controlling the first control valve 510 and the second control valve 520 to have the same opening and closing state, and controlling the third control valve 530 to have the opposite opening and closing state to the first control valve 510, according to the acquired load mode, specifically includes:

[0119] Step S41: When the load mode is the first load mode, the variable flow path module adopts the full flow path mode, that is, controls the first control valve 510 and the second control valve 520 to be turned on, and controls the third control valve 530 to be turned off.

[0120] Step S42: When the load mode is the second load mode, the variable flow path module adopts a half flow path mode, that is, it controls the first control valve 510 and the second control valve 520 to close, and controls the third control valve 530 to open, wherein the first load is greater than the second load.

[0121] Please combine Figure 3 When the heat exchanger is used as an evaporator and is in the first load mode, the variable flow path adopts the full flow path mode. The first control valve 510 and the second control valve 520 are opened, and the third control valve 530 is closed. The phase change working fluid can flow in from the liquid collection pipe 100, and after passing through the separable module 800, it enters the gas-liquid separator 700. Part of the evaporated gas is separated and flows out through the fourth control valve 540. One part of the liquid flows into the first heat exchange tube group 300 through the fifth pipe 650 and the first control valve 510, and the other part flows into the second heat exchange tube group 400 through the seventh pipe 670. The phase change working fluid flowing out of the first heat exchange tube group 300 flows into the gas collection pipe 200 through the fourth pipe 640. The phase change working fluid flowing out of the second heat exchange tube group 400 flows into the gas collection pipe 200 through the sixth pipe 660 and the second control valve 520.

[0122] When the heat exchanger is used as a condenser and is in the first load mode, the phase change working fluid flows in through the gas collecting pipe 200, and then flows into the first heat exchange tube group 300 through the fourth pipe 640, and into the second heat exchange tube group 400 through the sixth pipe 660 and the second solenoid valve. The phase change working fluid flowing out of the first heat exchange tube group 300 flows into the gas-liquid separator 700 through the fifth pipe 650 and the first solenoid valve. The phase change working fluid flowing out of the second heat exchange tube group 400 flows into the gas-liquid separator 700 through the seventh pipe 670. In summary, as long as the heat exchanger is in the first load mode, the number of flow paths for the phase change working fluid is the sum of the first heat exchange tube group 300 and the second heat exchange tube group 400. The large number of heat exchange flow paths increases the heat exchange capacity under higher load operation modes, achieving better heat exchange performance. This configuration increases the number of heat exchange flow paths to meet the increased heat exchange capacity required when the heat exchanger is used as an evaporator, thus achieving higher heat exchange efficiency.

[0123] Please combine Figure 4Whether in evaporation or condensation mode, when the heat exchanger is in the second load mode, it adopts a semi-flow path mode. By closing the first control valve 510 and the second control valve 520, and only opening the third control valve 530, the first heat exchange tube group 300 and the second heat exchange tube group 400 are connected in series. This reduces the number of flow paths under low load operation, thereby increasing the flow rate of the phase change working fluid. This meets the requirement of increasing the heat transfer coefficient under low load operation and achieves better heat exchange effect.

[0124] Optionally, when the fourth control valve 540 is an electronic expansion valve, the flow path control method for the heat exchanger further includes:

[0125] Step S5: Obtain the target operating frequency Fr of the refrigeration system;

[0126] Step S6: Determine the magnitude of the target operating frequency Fr and the third preset value c, where c = l*(Fmax + Fmin), l ranges from 0.45 to 0.75, Fmax is the maximum allowable operating frequency of compressor 2000, and Fmin is the minimum allowable operating frequency of compressor 2000;

[0127] Step S7: Based on the judgment result, obtain the initial opening degree and holding time of the electronic expansion valve, and perform initialization control.

[0128] In this embodiment, when the fourth control valve 540 is an electronic expansion valve, in order to enhance the heating effect, the electronic expansion valve is opened when the heat exchanger is in evaporation mode. The initial opening degree and holding time of the electronic expansion valve are set according to the target operating frequency of the refrigeration system, thereby effectively saving energy and improving the efficiency of gas-liquid separation.

[0129] Specifically, the target operating frequency is compared with a third preset value c. Here, the third preset value is the ratio of the sum of the maximum and minimum operating frequencies of the compressor 2000. The ratio coefficient l ranges from 0.45 to 0.75, for example, 0.5, 0.6, or 0.7. In a preferred embodiment, the ratio coefficient is selected as 0.5, so that the target operating frequency is compared with half of the sum of Fmax and Fmin, which can best reflect the load mode of the refrigeration system. This allows for more accurate initial control of the opening and holding time of the electronic expansion valve, thereby improving heat exchange efficiency.

[0130] Optionally, the step of obtaining the initial opening degree and holding time of the electronic expansion valve based on the judgment result and performing initialization control specifically includes:

[0131] Step S71: If Fr≤c, then set the initial opening of the electronic expansion valve to the first opening A, and the holding time to t1;

[0132] Step S72: If Fr > c, then set the initial opening of the electronic expansion valve to the second opening B, and maintain it for t2.

[0133] Where A is less than B, the range of the first opening A is 20P to 100P, the range of the second opening B is 50P to 150P; the range of t1 is 2min to 15min, and the range of t2 is 1min to 15min.

[0134] Specifically, the heat exchanger is in heating mode. Combined with the obtained frequency Fr of compressor 2000, the operating mode of the heat exchanger is further determined. If the target operating frequency Fr of compressor 2000 is ≤ c, it indicates that the target operating frequency of compressor 2000 is low, meaning the heat exchanger may be operating under low load. Therefore, the opening degree of the electronic expansion valve can be set to a relatively small first opening degree A. Here, A ranges from 20P to 100P, for example, 30P, 40P, 50P, 60P, 70P, 80P, 90P, etc., preferably 50P. The maintenance time is t1, ranging from 2min to 15min, for example, 3min, 4min, 5min, 6min, 8min, 10min, 12min, etc. In a preferred embodiment, t1 is set to 5min, thereby effectively saving energy and improving heat exchange efficiency while meeting low load requirements. If Fr > c, it indicates that the compressor 2000 target operating frequency is high, and the heat exchanger may be operating under high load. Therefore, the initial opening of the electronic expansion valve is set to the second opening B, where B ranges from 50P to 150P, for example, 50P, 60P, 70P, 80P, 90P, 100P, 120P, 140P, etc. In a preferred embodiment, the second opening B is selected as 80P, and the holding time is t2, which ranges from 1min to 15min, for example, 2min, 3min, 4min, 5min, 6min, 8min, 10min, 12min, etc. Preferably, t2 is selected as 2min, thereby ensuring the heat exchange effect while meeting the high load requirements.

[0135] The present invention also provides a readable storage medium storing a flow path control program for a heat exchanger, wherein when the flow path control program for the heat exchanger is executed by a processor, the flow path control program for the heat exchanger implements the steps of the flow path control method for the heat exchanger described above.

[0136] Specific embodiments of the readable storage medium of the present invention can be found in the various embodiments of the flow path control method for the heat exchanger described above, and will not be repeated here.

[0137] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A flow path control method for a heat exchanger, characterized in that, The heat exchanger is used in a refrigeration system and includes: Collection tube; Gas collection tube; A gas-liquid separator, comprising two liquid ends and one gas end, wherein the gas end is connected to the gas collecting pipe via a first pipeline; A separable module, one end of which is connected to the liquid end of the gas-liquid separator via a second pipeline, and the other end of which is connected to the liquid collection pipe via a third pipeline; A variable flow path module, comprising: a first heat exchange tube group, a second heat exchange tube group, and a control valve assembly, wherein the control valve assembly comprises a first control valve, a second control valve, and a third control valve; One end of the first heat exchange tube assembly is connected to the gas collecting pipe through the fourth pipe, and the other end is connected to the other liquid end through the fifth pipe; one end of the second heat exchange tube assembly is connected to the gas collecting pipe through the sixth pipe, and the other end is connected to the other liquid end through the seventh pipe. The first control valve is located in the fifth pipeline, and the second control valve is located in the sixth pipeline; the third control valve has a first end and a second end that are interconnected, the first end being connected to the end of the first control valve away from the gas collecting pipe, and the second end being connected to the end of the second control valve away from the other liquid end; and The fourth control valve is located on the first pipeline; The flow path control method includes: Obtain the operating mode of the heat exchanger and the load mode of the refrigeration system; When the operating mode is evaporation mode, the fourth control valve is turned on. When the operating mode is condensation mode, the fourth control valve is closed. Based on the obtained load mode, the opening and closing states of the first control valve and the second control valve are controlled to be the same, and the opening and closing states of the third control valve are controlled to be opposite to those of the first control valve. When the fourth control valve is an electronic expansion valve, the flow path control method for the heat exchanger further includes: Obtain the target operating frequency Fr of the refrigeration system; Determine the magnitude of the target operating frequency Fr and the third preset value c, where c = l * (Fmax + Fmin), l ranges from 0.45 to 0.75, Fmax is the maximum operating frequency of the compressor, and Fmin is the minimum operating frequency of the compressor; Based on the judgment result, the initial opening degree and holding time of the electronic expansion valve are obtained, and initialization control is performed; The specific steps for obtaining the initial opening degree and holding time of the electronic expansion valve based on the judgment result and performing initialization control are as follows: If Fr≤c, then the initial opening of the electronic expansion valve is set to the first opening A, and the holding time is t1; If Fr > c, then the initial opening of the electronic expansion valve is set to the second opening B, and the holding time is t2; Where A is less than B, the range of the first opening A is 20P~100P, and the range of the second opening B is 50P~150P; The range of t1 is 2 min to 15 min, and the range of t2 is 1 min to 15 min.

2. The flow path control method for a heat exchanger as described in claim 1, characterized in that, The separable module includes two first separation flow paths, which are connected in parallel.

3. The flow path control method for a heat exchanger as described in claim 2, characterized in that, The separable module further includes a second separation flow path, wherein the two first separation flow paths are connected in parallel and then connected in series with the second separation flow path.

4. The flow path control method for a heat exchanger as described in claim 2, characterized in that, The single-path flow length of the separable module is 0.15 to 0.55 times that of the single-path flow length of the variable-path module.

5. The flow path control method for a heat exchanger as described in any one of claims 1 to 4, characterized in that, The first control valve is a first check valve, and the conduction direction of the first check valve is from the other liquid end to the first heat exchange tube assembly; And / or, the second control valve is a second check valve, and the conduction direction of the second check valve is from the second heat exchange tube group to the gas collecting pipe.

6. The flow path control method for a heat exchanger as described in claim 5, characterized in that, The first heat exchange tube group and the second heat exchange tube group are each provided with at least two, with at least two first heat exchange tube groups and at least two second heat exchange tube groups being arranged in parallel; The third control valve is provided such that the end of each of the first heat exchange tube groups near the liquid collection pipe is connected to the first end; and the end of each of the second heat exchange tube groups near the gas collection pipe is connected to the second end.

7. The flow path control method for a heat exchanger as described in any one of claims 1 to 4, characterized in that, The fourth control valve is a third check valve, and the conduction direction of the third check valve is from the gas end to the gas collecting pipe; Alternatively, the fourth control valve may be an electronic expansion valve or a capillary.

8. The flow path control method for a heat exchanger as described in any one of claims 1 to 4, characterized in that, The steps of obtaining the operating mode of the heat exchanger and the load mode of the refrigeration system include: To determine the direction of refrigerant flow; When the flow direction of the refrigerant is detected as flowing from the liquid collection pipe to the gas collection pipe, the heat exchanger is determined to be in evaporation mode. When the flow direction of the refrigerant is detected as flowing from the gas collecting pipe to the liquid collecting pipe, the heat exchanger is determined to be in condensation mode.

9. The flow path control method for a heat exchanger as described in any one of claims 1 to 4, characterized in that, The specific steps for controlling the first control valve to have the same opening and closing state as the second control valve, and controlling the third control valve to have the opposite opening and closing state to the first control valve, based on the obtained load mode, are as follows: When the load mode is the first load mode, the variable flow path module adopts the full flow path mode, that is, it controls the first control valve and the second control valve to be turned on, and controls the third control valve to be turned off; When the load mode is the second load mode, the variable flow path module adopts a half flow path mode, that is, it controls the first control valve and the second control valve to close and controls the third control valve to open, wherein the first load is greater than the second load.

10. A readable storage medium, characterized in that, The readable storage medium stores a flow path control program for a heat exchanger, which, when executed by a processor, implements the steps of the flow path control method for a heat exchanger as described in any one of claims 1 to 9.

11. An air conditioner, characterized in that, The heat exchanger includes one capable of performing the flow path control method for the heat exchanger as described in any one of claims 1 to 9.

12. The air conditioner as described in claim 11, characterized in that, The air conditioner includes an outdoor unit, and the heat exchanger is located inside the outdoor unit.

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