A plate heat exchanger and refrigeration system

Abstract

This invention relates to a plate heat exchanger and a refrigeration system. The plate heat exchanger includes: a heat exchanger body comprising multiple layers of heat exchange plates, which are stacked together to form multiple layers of refrigerant channels and multiple layers of heat exchange fluid channels. Refrigerant inlets and outlets are provided on the multiple layers of heat exchange plates, penetrating the thickness direction of the layers, and both are connected to the refrigerant channels; a heat exchange adjustment component including a slider and a drive element. The slider is slidably disposed in the refrigerant inlet, and the drive element is connected to the slider to drive the slider to slide within the refrigerant inlet to block at least a portion of the multiple layers of heat exchange fluid channels. By driving the slider to slide within the refrigerant inlet, the number of layers blocking the multiple layers of heat exchange fluid channels is adjusted, thereby changing the number of heat exchange layers on the heat exchange plate. This allows for control of enthalpy superheat under different operating conditions, achieving optimal energy efficiency for air conditioning under enthalpy-increasing conditions.

Description

Technical Field

[0001] This invention relates to the field of heat exchanger technology, and more particularly to a plate heat exchanger and a refrigeration system. Background Technology

[0002] A plate heat exchanger is a high-efficiency heat exchanger composed of a series of stacked metal plates. Thin rectangular channels are formed between the various heat exchange plates, through which heat exchange occurs. Plate heat exchangers are ideal devices for liquid-liquid and liquid-vapor heat exchange. They feature high heat exchange efficiency, low heat loss, compact and lightweight structure, small footprint, wide application, and long service life.

[0003] In the field of multi-split air conditioning systems, plate heat exchangers serve as crucial enthalpy-increasing components to enhance system capacity and energy efficiency. Enthalpy increase in air conditioning systems via plate heat exchangers can increase the subcooling of the refrigerant before throttling, thereby increasing cooling capacity. Furthermore, enthalpy increase can lower the compressor discharge temperature, ensuring compressor reliability. Due to cost considerations or technical reasons, multi-split systems typically only equip themselves with one plate heat exchanger. However, conventional plate heat exchangers have a fixed heat exchange capacity, which cannot meet the demands of various operating conditions. The refrigerant flow rate differs between nominal, intermediate, and minimum load points in cooling and heating operations, as well as in low-temperature heating conditions. Consequently, the flow rates of the main heat exchange path and the enthalpy-increasing path differ, resulting in significant differences in the actual superheat of the enthalpy-increasing path.

[0004] Compressor enthalpy increase tests show that, within a certain range, compressor efficiency increases with increasing enthalpy increase pressure and decreases with increasing enthalpy increase superheat. Therefore, during system enthalpy increase testing, the enthalpy increase pressure can be increased to reduce enthalpy increase superheat. However, during air conditioning system matching tests, because the heat exchanger is fixed, only the enthalpy increase pressure can be adjusted. Since the actual compressor capacity and efficiency are related to both enthalpy increase pressure and enthalpy increase superheat, adjusting only the enthalpy increase pressure cannot find the optimal point for the air conditioning system. Summary of the Invention

[0005] To address the problem that plate heat exchangers in related technologies have fixed heat exchange capacity, which is not conducive to matching tests of air conditioners and cannot maximize the capacity and energy efficiency of air conditioners, this invention provides a plate heat exchanger and a refrigeration system.

[0006] This invention provides a plate heat exchanger, comprising: a heat exchanger body including multiple layers of heat exchange plates, the multiple layers of heat exchange plates being stacked together to form multiple layers of refrigerant channels and multiple layers of heat exchange fluid channels, wherein refrigerant inlets and refrigerant outlets are provided on the multiple layers of heat exchange plates, and the refrigerant inlets and refrigerant outlets are both connected to the refrigerant channels; and a heat exchange adjustment assembly including a slider and a driving component, wherein the slider is slidably disposed in the refrigerant inlets, and the driving component is connected to the slider for driving the slider to slide in the refrigerant inlets to block at least a portion of the multiple layers of heat exchange fluid channels.

[0007] In some embodiments, the slider is provided with a flow hole communicating with the refrigerant inlet, the flow hole being used to discharge the refrigerant in the refrigerant inlet during the sliding of the slider.

[0008] In some embodiments, the heat exchanger body further includes a first mounting plate and a second mounting plate disposed on both sides of the multilayer heat exchange plates. The first mounting plate and the second mounting plate are connected to fix the multilayer heat exchange plates. An inlet communicating with the refrigerant inlet and an outlet communicating with the refrigerant outlet are provided on the first mounting plate.

[0009] In some embodiments, the driving component includes a motor and a lead screw. The motor is fixed to the second mounting plate. One end of the lead screw is connected to the output end of the motor, and the other end extends through the second mounting plate into the refrigerant inlet. The slider is threadedly connected to the lead screw.

[0010] In some embodiments, the heat exchange regulating assembly further includes a guide member disposed in the refrigerant inlet and slidably connected to the slider. One end of the guide member is fixed to the first mounting plate, and the other end passes through the slider and extends toward the second mounting plate.

[0011] In some embodiments, the motor is fixed to the second mounting plate by a mounting block located between the second mounting plate and the motor. The mounting block has a slider receiving cavity for avoiding the slider. The lead screw passes through the mounting block and is provided with a first seal between the lead screw and the mounting block. A second seal is provided between the mounting block and the second mounting plate.

[0012] In some embodiments, multi-layer refrigerant channels and multi-layer heat exchange fluid channels are arranged alternately in the thickness direction of the heat exchanger body.

[0013] In some embodiments, the multilayer heat exchange plate is further provided with a heat exchange fluid inlet and a heat exchange fluid outlet extending through the thickness direction of the multilayer heat exchange plate; wherein the refrigerant inlet and the heat exchange fluid inlet are on the same side, and the refrigerant outlet and the heat exchange fluid outlet are on the same side.

[0014] The present invention also provides a refrigeration system, comprising: a refrigerant circulation loop; a plate heat exchanger as described in any of the above embodiments, wherein the inlet end of the refrigerant circulation loop is connected to the refrigerant outlet, and the outlet end of the refrigerant circulation loop is connected to the refrigerant inlet.

[0015] In some embodiments, the refrigeration system further includes: a detection device for detecting the temperature and / or pressure value of the refrigerant circulation loop; and a control circuit board connected to the detection device and the motor for controlling the motor to drive the slider to slide in the refrigerant inlet based on the temperature and / or pressure value.

[0016] By adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art:

[0017] By driving a slider to slide in the refrigerant inlet, the number of layers blocking the multi-layer heat exchange fluid channels can be adjusted, thereby changing the number of heat exchange layers of the heat exchange plate. This allows for control of enthalpy superheat under different operating conditions, enabling the air conditioner to achieve optimal energy efficiency under enthalpy conditions.

[0018] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description

[0019] The accompanying drawings, as part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention, but do not constitute an undue limitation of the invention. Obviously, the drawings described below are merely some embodiments, and those skilled in the art can obtain other drawings based on these drawings without creative effort. In the drawings:

[0020] Figures 1a to 1c This is a cross-sectional schematic diagram of a plate heat exchanger with different numbers of heat exchange plates when the slider is opened, according to an exemplary embodiment of the present invention.

[0021] Figure 2 This is a schematic diagram of a slider structure according to an exemplary embodiment of the present invention;

[0022] Figure 3a and Figure 3b This is a schematic diagram illustrating the flow direction of the refrigerant channel and the heat exchange fluid channel according to an exemplary embodiment of the present invention;

[0023] Figure 4 This is a perspective view of a plate heat exchanger according to an exemplary embodiment of the present invention;

[0024] Figure 5 This is a block diagram of a refrigeration system according to an exemplary embodiment of the present invention;

[0025] It should be noted that these accompanying drawings and textual descriptions are not intended to limit the scope of the invention in any way, but rather to illustrate the concept of the invention to those skilled in the art by referring to specific embodiments. Detailed Implementation

[0026] In the description of this invention, it should be noted that the terms "inner" and "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0027] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," "contact," and "communication" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0028] like Figures 1a to 5 As shown, the present invention provides a plate heat exchanger, comprising: a heat exchanger body and a heat exchange adjustment assembly.

[0029] The heat exchanger body includes multiple layers of heat exchange plates 12, which are stacked together to form multiple layers of refrigerant channels 121 and multiple layers of heat exchange fluid channels 122. The multiple layers of refrigerant channels 121 and multiple layers of heat exchange fluid channels 122 can be arranged alternately along the thickness direction of the heat exchanger body. That is, the multiple layers of refrigerant channels 121 and multiple layers of heat exchange fluid channels 122 alternate with each other. Refrigerant inlets 123 and refrigerant outlets 124 are provided on the multiple layers of heat exchange plates 12, penetrating the thickness direction of the multiple layers of heat exchange plates. The refrigerant inlets 123 and refrigerant outlets 124 are respectively connected to the refrigerant channels 121.

[0030] The heat exchange regulating assembly includes a slider 21 and a driving component. The slider 21 is slidably disposed in the refrigerant inlet 123. The driving component is connected to the slider 21 and is used to drive the slider 21 to move so that the slider 21 blocks at least a portion of the refrigerant inlet 123, thereby regulating the number of layers of refrigerant entering the multi-layer refrigerant channel 121 from the refrigerant inlet 123.

[0031] like Figures 1a to 1c When it is necessary to adjust the heat exchange capacity of the plate heat exchanger, such as to increase the heat exchange capacity, the slider 21 can be moved by the driving component to reduce the number of layers of refrigerant channel 121 blocked by the slider 21. This can achieve the control of enthalpy superheat under different operating conditions and achieve the best energy efficiency of the air conditioner under enthalpy state.

[0032] In some embodiments, the heat exchanger body further includes a first mounting plate 11 and a second mounting plate 13 disposed on both sides of the multilayer heat exchange plates. The first mounting plate 11 and the second mounting plate 13 are connected together to fix the multilayer heat exchange plates 12, thereby clamping the multilayer heat exchange plates 12 between the first mounting plate 11 and the second mounting plate 13. The first mounting plate 11 is provided with an inlet 111 communicating with a refrigerant inlet 123 and an outlet 112 communicating with a refrigerant outlet 124. The second mounting plate 13 is provided with a through hole corresponding to and communicating with the refrigerant inlet 123.

[0033] The multi-layer heat exchanger plate 12 is also provided with a heat exchange fluid inlet 125 and a heat exchange fluid outlet 126 that penetrate through the thickness direction of the multi-layer heat exchanger plate; wherein the refrigerant inlet 123 is on the same side as the heat exchange fluid inlet 125, and the refrigerant outlet 124 is on the same side as the heat exchange fluid outlet 126.

[0034] In some embodiments, such as Figure 2 As shown, the slider 21 is provided with a flow hole 211. The flow hole 211 is used to discharge the refrigerant in the refrigerant inlet 123 during the sliding process of the slider 21 in the refrigerant inlet 123, so as to prevent the liquid in the refrigerant inlet 123 from being compressed.

[0035] In some embodiments, the driving component includes a motor 22 and a lead screw 23. The motor 22 is fixed to the second mounting plate 13, the lead screw 23 is connected to the output end of the motor, and the slider 21 is threadedly connected to the lead screw 23. The rotation of the motor 22 drives the lead screw 23 to rotate, thereby causing the slider 21 to slide in the refrigerant inlet 123, thereby changing the number of layers of refrigerant entering the multi-layer refrigerant channel 121 from the refrigerant inlet 123.

[0036] In some embodiments, the heat exchange regulating assembly further includes a guide member 24, which is disposed within the refrigerant inlet 123 and slidably connected to the slider 21. One end of the guide member 24 is fixed to the first mounting plate 11, and the other end passes through the slider 21 and extends toward the second mounting plate 13. The guide member 24 guides the slider 21 as it slides within the refrigerant inlet 123, preventing the slider from rotating with the lead screw 23.

[0037] In some embodiments, the motor 22 is fixed to the second mounting plate 13 by a mounting block located between the second mounting plate 13 and the motor 22. The mounting block has a slider receiving cavity for avoiding the slider 21. The lead screw 23 passes through the mounting block and is provided with a first seal between the mounting block and the mounting block. A second seal is provided between the mounting block and the second mounting plate 13.

[0038] The mounting block and motor 22 are fixed to the second mounting plate 13 with screws. There is a radial first seal between the lead screw 23 and the slider cavity of the mounting block, and an axial second seal between the slider and the second mounting plate 13 to prevent fluid leakage inside the plate heat exchanger. The slider 21 is driven by the lead screw 23 and moves along the thickness direction of the heat exchange plate 12. During the movement, it can block the fluid from entering the circulation between the layers of the multi-layer half plate, thereby achieving the purpose of controlling the heat exchange.

[0039] Specifically, the slider 21 is installed in the refrigerant inlet 123. When the heat exchange capacity needs to be adjusted, the stepper motor 22 can be adjusted to control the lead screw 23 to drive the slider 21 to move, thereby affecting the number of heat exchange plates 12 participating in heat exchange. Since the number of layers participating in heat exchange in the multi-layer heat exchange fluid channel 122 remains unchanged, while the number of layers participating in heat exchange in the multi-layer refrigerant channel 121 changes, the heat exchange capacity of the plate heat exchanger is affected. More preferably, the length of the slider 21 can completely cover the refrigerant inlet 123, and when the slider returns completely to the slider cavity, the slider will not obstruct the heat exchange of each layer of the refrigerant inlet 123. Figure 1a When slider 21 moves to the right, the number of heat exchange fins participating in heat exchange increases, meaning the number of refrigerant channels 121 increases, and the heat exchange capacity increases; when slider 21 moves to the left... Figure 1b As the heat exchange gradually decreases, when the slider moves to its extreme position to the left, such as Figure 1c As shown, the multi-layer heat exchange fluid channel 122 does not participate in heat exchange, and the plate heat exchanger does not work at this time.

[0040] The present invention also provides a refrigeration system, such as Figure 5 As shown, it includes a refrigerant circulation loop; as in any of the above embodiments, the inlet end of the refrigerant circulation loop is connected to the refrigerant outlet, and the outlet end of the refrigerant circulation loop is connected to the refrigerant inlet.

[0041] The refrigeration system also includes: a detection device for detecting the temperature and / or pressure values ​​of the refrigerant circulation loop; and a control circuit board connected to the detection device and the motor for controlling the motor to drive the slider to slide in the refrigerant inlet based on the temperature and / or pressure values.

[0042] The refrigeration system can be a multi-split system, using a plate heat exchanger to achieve superheat of the makeup gas. Its enthalpy increase is achieved by an electronic expansion valve controlling the pressure, with the makeup gas temperature obtained through heat exchange in the plate heat exchanger. Conventional plate heat exchangers have non-adjustable heat exchange capacity, so the makeup gas superheat is uncontrollable and can only be monitored. By using the adjustable heat exchange plate heat exchanger of this invention, multi-split systems can freely adjust the makeup gas superheat, adapting to different test conditions and thus improving the overall system energy efficiency.

[0043] The specific adjustment process is as follows: For refrigeration systems, such as air conditioning systems, adjusting the opening of the electronic expansion valve in the enthalpy-increasing circuit regulates the enthalpy-increasing pressure. The effect of enthalpy-increasing pressure on compressor efficiency is parabolic. Increasing the pressure helps find the optimal efficiency value. However, as the pressure increases, the superheat of the injection gas decreases. When the superheat is low, the compressor faces the risk of liquid carryover during injection. To avoid liquid carryover, the heat exchanger heat transfer can be increased (the slider moves to the right), thereby increasing the superheat of the injection gas. A relationship between the superheat of the injection gas and the slider position can be established. For example... Figure 5 As shown in the system implementation plan, the enthalpy increase control board monitors the enthalpy increase pressure and temperature, calculates the superheat of the make-up gas, and automatically adjusts the slider position when the measured value is inconsistent with the set value to control the superheat. During the actual adjustment process of the air conditioning system, the make-up gas pressure can be adjusted first. When the energy efficiency reaches the optimal level, the heat exchange is adjusted to reach the set make-up gas superheat. To prevent liquid carryover in the make-up gas, the make-up gas superheat can be initially set to 5°C.

[0044] It can be further understood that in this disclosure, "multiple" refers to two or more, and other quantifiers are similar. "And / or" describes the relationship between related objects, indicating that three relationships can exist; for example, A and / or B can represent: A alone, A and B simultaneously, and B alone. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. The singular forms "a," "the," and "the" are also intended to include the plural forms unless the context clearly indicates otherwise.

[0045] It is further understood that the terms "first," "second," etc., are used to describe various types of information, but this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another, and do not indicate a specific order or degree of importance. In fact, the expressions "first," "second," etc., are completely interchangeable. For example, without departing from the scope of this disclosure, first information can also be referred to as second information, and similarly, second information can also be referred to as first information.

[0046] It is further understood that although operations are described in a specific order in the accompanying drawings in the embodiments of this disclosure, this should not be construed as requiring these operations to be performed in the specific order or serial order shown, or requiring all of the shown operations to be performed to obtain the desired result. In certain environments, multitasking and parallel processing may be advantageous.

[0047] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the following claims.

[0048] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

Claims

1. A plate heat exchanger, characterized in that, include: The heat exchanger body includes multiple layers of heat exchange plates, which are stacked together to form multiple layers of refrigerant channels and multiple layers of heat exchange fluid channels. Refrigerant inlets and refrigerant outlets are provided on the multiple layers of heat exchange plates, which penetrate the thickness direction of the multiple layers of heat exchange plates. Both the refrigerant inlets and refrigerant outlets are connected to the refrigerant channels. A heat exchange regulating component includes a slider and a driving component. The slider is slidably disposed in the refrigerant inlet. The driving component is connected to the slider. The slider is driven to slide in the refrigerant inlet by the driving component, which can block at least part of the multi-layer heat exchange fluid channels and can adjust the number of layers of multi-layer heat exchange fluid channels blocked. The slider is provided with a flow hole communicating with the refrigerant inlet, and the flow hole is used to discharge the refrigerant in the refrigerant inlet during the sliding of the slider.

2. The plate heat exchanger according to claim 1, characterized in that, The heat exchanger body also includes a first mounting plate and a second mounting plate disposed on both sides of the multi-layer heat exchange plates, the first mounting plate and the second mounting plate being connected to fix the multi-layer heat exchange plates. The first mounting plate is provided with an inlet that communicates with the refrigerant inlet and an outlet that communicates with the refrigerant outlet.

3. The plate heat exchanger according to claim 2, characterized in that, The driving component includes a motor and a lead screw. The motor is fixed to the second mounting plate. One end of the lead screw is connected to the output end of the motor, and the other end extends through the second mounting plate into the refrigerant inlet. The slider is threadedly connected to the lead screw.

4. The plate heat exchanger according to claim 3, characterized in that, The heat exchange regulating assembly also includes a guide member, which is disposed in the refrigerant inlet and slidably connected to the slider. One end of the guide member is fixed to the first mounting plate, and the other end passes through the slider and extends toward the second mounting plate.

5. The plate heat exchanger according to claim 4, characterized in that, The motor is fixed to the second mounting plate by a mounting block located between the second mounting plate and the motor. The mounting block has a slider receiving cavity to avoid the slider. The lead screw passes through the mounting block and is provided with a first sealing element between the lead screw and the mounting block. A second sealing element is provided between the mounting block and the second mounting plate.

6. The plate heat exchanger according to any one of claims 1-5, characterized in that, Multi-layer refrigerant channels and multi-layer heat exchange fluid channels are arranged alternately in the thickness direction of the heat exchanger body.

7. The plate heat exchanger according to claim 6, characterized in that, The multilayer heat exchange plate is also provided with a heat exchange fluid inlet and a heat exchange fluid outlet that penetrate through the thickness direction of the multilayer heat exchange plate. The refrigerant inlet is on the same side as the heat exchange fluid inlet, and the refrigerant outlet is on the same side as the heat exchange fluid outlet.

8. A refrigeration system, characterized in that, include: Refrigerant circulation loop; In the plate heat exchanger as described in any one of claims 1-7, the inlet end of the refrigerant circulation loop is connected to the refrigerant outlet, and the outlet end of the refrigerant circulation loop is connected to the refrigerant inlet.

9. The refrigeration system according to claim 8, characterized in that, Also includes: The detection device is used to detect the temperature and / or pressure values ​​of the refrigerant circulation loop; A control circuit board, connected to the detection device and the motor, is used to control the motor to drive the slider to slide in the refrigerant inlet based on the temperature value and / or pressure value.

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