Plate heat exchanger

Abstract

The application relates to a plate heat exchanger, which comprises a first partition plate, a second partition plate and a shunt pipe, the first partition plate is arranged at intervals along a preset height direction in a hot flow inlet liquid channel to separate the hot flow inlet liquid channel into multiple hot flow inlet liquid sections; the second partition plate is arranged at intervals along a preset height direction in a hot flow outlet liquid channel to separate the hot flow outlet liquid channel into multiple hot flow outlet liquid sections; the first partition plate and the second partition plate are arranged in a staggered mode to make the hot flow inlet liquid sections, hot flow layers and hot flow outlet liquid sections sequentially and circularly communicated; the shunt pipe is sequentially arranged in the multiple hot flow inlet liquid sections, the inner walls of the shunt pipe and the hot flow inlet liquid sections are arranged at intervals, and the side wall of the shunt pipe is provided with a communication hole communicating with the corresponding hot flow inlet liquid section, so that at least part of gaseous refrigerant in one hot flow inlet liquid section enters another hot flow inlet liquid section through the shunt pipe. The plate heat exchanger provided by the application solves the problem of the decrease of the refrigerant heat exchange coefficient in the process of the water-cooled condenser.

Description

Technical Field

[0001] This application relates to the field of heat exchanger technology, and in particular to a plate heat exchanger. Background Technology

[0002] During the operation of an air conditioning and thermal management system, high-temperature, high-pressure refrigerant gas enters a water-cooled condenser (usually a plate heat exchanger structure) and exchanges heat with the flowing cooling water, transferring a large amount of heat to the cooling water. In this process, the refrigerant gas is first cooled to a gas-liquid two-phase state, and then the proportion of the liquid phase continues to increase until it is completely condensed into a liquid state. Depending on the actual operating conditions and system design, it may further reach different degrees of subcooling.

[0003] To improve the heat exchange performance of water-cooled condensers, a multi-pass arrangement is commonly used on the refrigerant side. This involves changing the refrigerant flow direction multiple times and extending its heat exchange path between the plates, thereby avoiding incomplete condensation due to a short flow path.

[0004] However, as the condensation process progresses, the mass fraction of the gas phase in the gas-liquid mixture (i.e., the proportion of gaseous refrigerant) continuously decreases, leading to a significant reduction in the latent heat released through phase change. Since the phase change heat released by gaseous condensation is much higher than the heat released by liquid refrigerant through sensible heat changes, this phenomenon causes a sharp decrease in the overall heat transfer coefficient on the refrigerant side, severely limiting the performance of water-cooled condensers. Utility Model Content

[0005] Therefore, there is an urgent need to develop a new type of plate heat exchanger to improve the problem of the continuous decrease in the refrigerant heat transfer coefficient of existing water-cooled condensers during process advancement.

[0006] The plate heat exchanger provided in this application includes a hot flow inlet channel, a hot flow outlet channel, a cold flow inlet channel, a cold flow outlet channel, a hot flow layer, and a cold flow layer. The hot flow layer and the cold flow layer are alternately distributed along a preset height direction of the plate heat exchanger. The cold flow inlet channel, each cold flow layer, and the cold flow outlet channel are sequentially connected. The plate heat exchanger includes a first partition, a second partition, and a distribution pipe. The first partition is spaced along the preset height direction in the hot flow inlet channel to divide the hot flow inlet channel into multiple hot flow inlet sections arranged sequentially along the preset height direction. The second partition is spaced along the preset height direction in the hot flow outlet channel... The outflow channel is divided into multiple hot outflow sections arranged sequentially along a predetermined height direction. Along the predetermined height direction, the first and second partitions are staggered to allow the hot inflow section, hot flow layer, and hot outflow section to be sequentially circulated and connected to form a refrigerant flow structure with multiple detours. The diverter is sequentially installed through multiple hot inflow sections, with the inner walls of the diverter and the hot inflow sections spaced apart. The side wall of the diverter is provided with a connecting hole that connects to the corresponding hot inflow section, so that at least part of the gaseous refrigerant in one hot inflow section can enter another hot inflow section through the diverter.

[0007] In one embodiment, the manifold connects all the hot liquid inlet sections.

[0008] In one embodiment, the total area of ​​the connecting hole between the splitter pipe and the corresponding hot flow inlet section tends to increase along the direction from the inlet end of the splitter pipe to the outlet end.

[0009] In one embodiment, the annular channel between the manifold and the inner wall of the hot flow inlet section is defined as the main flow channel, and the flow area A of the manifold and the flow area B of the main flow channel satisfy 0.02≤A / (A+B)≤0.5.

[0010] In one embodiment, the manifold is disposed in the hot liquid inlet channel, and the height difference H between the end face of the manifold and the end face of the hot liquid inlet channel satisfies H≤2mm.

[0011] In one embodiment, the plate heat exchanger further includes a flow-limiting sleeve and a sealing cover. The flow-limiting sleeve is fitted around the outer periphery of the distribution tube and sealed through the first partition. The inner wall of the flow-limiting sleeve is spaced apart from the outer wall of the distribution tube, and the outer wall of the flow-limiting sleeve is spaced apart from the inner wall of the hot liquid inlet channel. The sealing cover is sealed over the inlet end of the region between the flow-limiting sleeve and the inner wall of the hot liquid inlet channel, so that the refrigerant at the inlet end of the hot liquid inlet channel can enter the distribution tube and the region between the outer wall of the distribution tube and the inner wall of the flow-limiting sleeve, respectively. The distribution tube, the flow-limiting sleeve, and the inner wall of the hot liquid inlet channel are connected by the first partition. The side wall of the flow-limiting sleeve is provided with an outlet hole. The flow-limiting sleeve is connected to the hot liquid inlet channel through the outlet hole. The distribution tube can connect to the region between the inner wall of the hot liquid inlet channel and the outer wall of the flow-limiting sleeve in sequence through the connecting hole and the outlet hole.

[0012] In one embodiment, the plate heat exchanger further includes a core plate, with adjacent core plates forming a hot flow layer and a cold flow layer. The first partition includes a first partition and a second partition. The core plate extends toward the outer wall of the flow-limiting sleeve to form the first partition. The first partition separates the area between the inner wall of the hot flow inlet channel and the outer wall of the flow-limiting sleeve, and the second partition separates the area between the inner wall of the flow-limiting sleeve and the outer wall of the diversion pipe.

[0013] In one embodiment, the annular channel between the diverter and the flow-limiting sleeve is defined as the first flow channel, and the flow area A of the diverter and the flow area C of the first flow channel satisfy 0.1≤A / (A+C)≤0.5.

[0014] In one embodiment, the plate heat exchanger further includes a flow restrictor cover, which covers the inlet end of the region between the distribution pipe and the inner wall of the hot liquid inlet channel. The flow restrictor cover has a flow restrictor hole so that the refrigerant at the inlet end of the hot liquid inlet channel can enter the region between the distribution pipe and the inner wall of the hot liquid inlet channel through the flow restrictor hole.

[0015] In one embodiment, the plate heat exchanger further includes a flow-limiting tube and a sealing cap. The flow-limiting tube is inserted inside the distribution tube, with its outer wall spaced apart from the inner wall of the distribution tube. The outer wall of the distribution tube is also spaced apart from the inner wall of the hot flow inlet channel. The sealing cap is positioned at the inlet end of the region between the distribution tube and the inner wall of the hot flow inlet channel, allowing the refrigerant at the inlet end of the hot flow inlet channel to enter both the flow-limiting tube and the region between the inner wall of the distribution tube and the outer wall of the flow-limiting tube. The flow-limiting tube, the distribution tube, and the inner wall of the hot flow inlet channel are connected by a first partition. The side wall of the flow-limiting tube has a flow hole through which the flow-limiting tube connects to the distribution tube. The flow-limiting tube can sequentially connect to the region between the inner wall of the hot flow inlet channel and the outer wall of the distribution tube through the flow hole and the connecting hole.

[0016] Compared to existing technologies, the plate heat exchanger provided in this application, specifically, after the refrigerant enters the hot flow inlet channel, part of the gaseous refrigerant enters the inside of the distributor tube, while the remainder flows along the annular channel. The distributor tube transports the gaseous refrigerant to other hot flow inlet sections, allowing it to mix again with the refrigerant in subsequent processes. Through the staggered arrangement of the first and second baffles, the refrigerant flows sequentially through different hot flow inlet and outlet sections, forming a multi-fold flow path. During this process, the distributor tube continuously introduces the incompletely condensed gaseous refrigerant from the front end into subsequent processes, preventing the proportion of the gas phase from decreasing prematurely within a single process.

[0017] Compared with existing technologies, this solution achieves cross-process redistribution of gaseous refrigerant through a distribution pipe, maintaining a high proportion of gas phase in each process, thereby fully utilizing the latent heat of phase change to improve heat exchange efficiency. Furthermore, the meandering path formed by the staggered baffles extends the refrigerant flow distance, further enhancing the uniformity of the condensation process.

[0018] Through the above technical solution, this application can dynamically adjust the distribution of gaseous refrigerant in each process, avoiding a decrease in heat transfer coefficient due to excessively low local gas phase ratio. The gaseous refrigerant continuously participates in phase change heat transfer during multiple reversal flows, significantly improving the overall efficiency of the condensation process. The synergistic effect of the distributor, the first baffle, and the second baffle optimizes the refrigerant flow path, ensuring stable heat transfer performance throughout the process. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 A schematic diagram of the structure of a plate heat exchanger according to an embodiment of this application;

[0021] Figure 2 A cross-sectional view of the plate heat exchanger provided in Embodiment 1 of this application;

[0022] Figure 3 for Figure 2 The enlarged view at point Q is shown below;

[0023] Figure 4 A partial structural schematic diagram of the plate heat exchanger provided in Embodiment 1 of this application;

[0024] Figure 5 This is a partial cross-sectional view of the plate heat exchanger of Embodiment 2 provided in this application;

[0025] Figure 6 This is a partial structural schematic diagram of the plate heat exchanger of Embodiment 2 provided in this application.

[0026] Reference numerals: 110, Hot flow inlet pipe; 120, Hot flow outlet pipe; 130, Cold flow inlet pipe; 140, Cold flow outlet pipe; 150, Core plate; 160, Hot flow layer; 170, Cold flow layer; 200, Hot flow inlet channel; 210, First hot flow inlet section; 220, Second hot flow inlet section; 230, First flow channel; 300, Hot flow outlet channel; 310, First hot flow outlet section; 320, Second hot flow outlet section; 410, First partition; 411, First dividing part; 412, Second dividing part; 420, Second partition; 500, Diverter pipe; 510, Connecting hole; 600, Flow limiting sleeve; 610, Outlet hole; 700, Sealing cap; 800, Flow limiting cap; 810, Flow limiting hole. Detailed Implementation

[0027] Please see Figures 1-6 This application provides a plate heat exchanger, which includes a hot liquid inlet pipe 110, a hot liquid outlet pipe 120, a cold liquid inlet pipe 130, a cold liquid outlet pipe 140, and a plurality of core plates 150 alternately stacked along a predetermined height direction. The plate heat exchanger is provided with a hot liquid inlet channel 200, a hot liquid outlet channel 300, a cold liquid inlet channel (not shown), a cold liquid outlet channel (not shown), a hot liquid layer 160 (which may be a gaseous or gas-liquid mixture of refrigerant), and a cold liquid layer 170 (which may be a liquid coolant), the hot liquid layer 160 and the cold liquid layer 170 being alternately distributed along the predetermined height direction of the plate heat exchanger. Furthermore, adjacent core plates 150 form a hot flow layer 160 and a cold flow layer 170. The hot flow inlet pipe 110 connects to the hot flow inlet channel 200, the hot flow outlet pipe 120 connects to the hot flow outlet channel 300, the cold flow inlet pipe 130 connects to the cold flow inlet channel, and the cold flow outlet pipe 140 connects to the cold flow outlet channel. The hot flow inlet pipe 110 and the hot flow outlet pipe 120 are located at both ends of the plate heat exchanger along a predetermined height direction, while the cold flow inlet pipe 130 and the cold flow outlet pipe 140 can be located at either end of the plate heat exchanger along the predetermined height direction, or at the same end of the plate heat exchanger along the predetermined height direction.

[0028] The hot liquid inlet channel 200 is equivalent to the refrigerant inlet manifold, and the hot liquid outlet channel 300 is equivalent to the refrigerant outlet manifold. The hot liquid inlet channel 200 extends along a preset height direction and is connected to one end of each hot liquid layer 160. The hot liquid outlet channel 300 extends in the opposite direction of the preset height direction and is connected to the other end of each hot liquid layer 160. That is, the hot liquid inlet channel 200, each hot liquid layer 160, and the hot liquid outlet channel 300 are sequentially connected to form a refrigerant circulation channel structure. The cold liquid inlet channel is equivalent to the coolant inlet manifold, and the cold liquid outlet channel is equivalent to the coolant outlet manifold. The cold liquid inlet channel extends along a preset height direction and is connected to one end of each cold liquid layer 170. The cold liquid outlet channel extends in the opposite direction of the preset height direction and is connected to the other end of each cold liquid layer 170. That is, the cold liquid inlet channel, each cold liquid layer 170, and the cold liquid outlet channel are sequentially connected to form a coolant flow structure.

[0029] The plate heat exchanger also includes a first partition 410 and a second partition 420. One or more first partitions 410 are spaced apart along a preset height direction in the hot liquid inlet channel 200 to divide the hot liquid inlet channel 200 into multiple hot liquid inlet sections (which can be 2, 3 or more than 3 other numbers, not listed here) arranged sequentially along the preset height direction. These sections are defined as the first hot liquid inlet section 210, the second hot liquid inlet section 220, ..., the nth hot liquid inlet section. The first hot liquid inlet section 210 is closest to the refrigerant inlet, and the nth hot liquid inlet section is farthest from the refrigerant inlet.

[0030] One or more second partitions 420 are spaced apart along a preset height direction in the hot liquid outflow channel 300 to divide the hot liquid outflow channel 300 into multiple hot liquid outflow segments arranged sequentially along the preset height direction, which are defined sequentially as the first hot liquid outflow segment 310, the second hot liquid outflow segment 320, ..., the nth hot liquid outflow segment, wherein the nth hot liquid outflow segment is closest to the outlet of the refrigerant, and the first hot liquid outflow segment 310 is farthest from the outlet of the refrigerant.

[0031] The number of first partitions 410 and second partitions 420 is equal. Furthermore, the first partitions 410 and second partitions 420 are staggered along a preset height direction so that all other hot liquid inlet sections except the first hot liquid inlet section 210 can be connected to adjacent hot liquid outlet sections through the corresponding hot liquid layer 160. Also, all other hot liquid outlet sections except the nth hot liquid outlet section can be connected to adjacent hot liquid inlet sections through the corresponding hot liquid layer 160. In other words, the hot liquid inlet section, the hot liquid layer 160, and the hot liquid outlet section are sequentially and cyclically connected to form a refrigerant flow structure with multiple detours.

[0032] It should be noted that the forms of the hot flow inlet channel 200, hot flow outlet channel 300, cold flow inlet channel, and cold flow outlet channel are not unique. Specifically, there are several forms: The first form is that the core plate 150 has through holes, and the through holes at corresponding positions on each core plate 150 are connected vertically to form a corresponding hot flow layer 160 or a corresponding cold flow layer 170. When the through holes connect to the hot flow layer 160, multiple through holes connect to form the hot flow inlet channel 200 and the hot flow outlet channel 300; when the through holes connect to the cold flow layer 170, multiple through holes connect to form the cold flow inlet channel and the cold flow outlet channel. The second form is: based on the first form, the core plate 150 below the lowest hot flow layer 160... Alternatively, the base plate may have an opening to form a new hot liquid outlet, which is also part of the hot liquid outlet channel 300. The third form and the first form are parallel technical solutions. Specifically, the insert tube directly penetrates the core plate 150, and the tube wall has upper and lower spaced insertion holes, which are respectively connected to the corresponding hot liquid layer 160 or cold liquid layer 170. That is, when the insert tube is connected to the hot liquid layer 160, the insert tube forms a hot liquid inlet channel 200 and a hot liquid outlet channel 300. When the insert tube is connected to the cold liquid layer 170, the insert tube forms a cold liquid inlet channel and a cold liquid outlet channel. Of course, based on the third form, the structure of the second form can also be combined with the third form to form a fourth form of channel structure.

[0033] In order to improve the heat transfer coefficient of the refrigerant at the end of the process, this application proposes a channel structure that is completely different from the previous types. Specifically, the plate heat exchanger also includes a distribution pipe 500, which is sequentially installed through multiple hot flow inlet sections. The inner walls of the distribution pipe 500 and the hot flow inlet sections are spaced apart. The side wall of the distribution pipe 500 is provided with a connecting hole 510 that connects to the corresponding hot flow inlet section, so that at least part of the gaseous refrigerant in one of the hot flow inlet sections can enter the corresponding hot flow inlet section through the distribution pipe 500.

[0034] Taking an example where there is one first partition 410 and one second partition 420, the hot liquid inlet section is divided into a first hot liquid inlet section 210 and a second hot liquid inlet section 220 by the first partition 410, and the hot liquid outlet section is divided into a first hot liquid outlet section 310 and a second hot liquid outlet section 320 by the second partition 420. One end of the diverter pipe 500 starts from the inlet of the first hot liquid inlet section 210 and passes through the first hot liquid inlet section 210, the first partition 410 and the second hot liquid inlet section 220 in sequence. Furthermore, the connecting hole 510 is provided in the part of the diverter pipe 500 that connects to the second hot liquid inlet section 220. Thus, the first portion of refrigerant (including gaseous and liquid refrigerant) enters the corresponding heat flow layers 160 through the area between the distributor pipe 500 and the first hot flow inlet section 210, then enters the first hot flow outlet section 310 through the heat flow layer 160, and then detours through the next level of heat flow layers 160 to enter the area between the second hot flow inlet section 220 and the distributor pipe 500, and then detours through the next level of heat flow layers 160 to enter the second hot flow outlet section 320, finally leaving the plate heat exchanger. The second portion of refrigerant (including gaseous and liquid refrigerant) enters the area between the second hot flow inlet section 220 and the distributor pipe 500 through the distributor pipe 500 and the connecting hole 510, and merges with the first portion of refrigerant. Then, the merged first and second portions of refrigerant enter the second hot flow outlet section 320 through the next level of heat flow layers 160, finally leaving the plate heat exchanger.

[0035] Specifically, after the refrigerant enters the hot flow inlet channel 200, part of the gaseous refrigerant enters the distributor pipe 500, while the remainder flows along the annular channel. The distributor pipe 500 transports the gaseous refrigerant to other hot flow inlet sections, allowing it to mix again with the refrigerant in subsequent processes. Through the staggered arrangement of the first baffle 410 and the second baffle 420, the refrigerant flows sequentially through different hot flow inlet and outlet sections, forming a multi-fold flow path. During this process, the distributor pipe 500 continuously introduces the incompletely condensed gaseous refrigerant from the front end into subsequent processes, preventing the proportion of the gas phase from decreasing prematurely within a single process.

[0036] Compared with existing technologies, this solution achieves cross-process redistribution of gaseous refrigerant through the distributor 500, maintaining a high proportion of gas phase in each process, thereby fully utilizing the latent heat of phase change to improve heat exchange efficiency. In addition, the tortuous path formed by the staggered baffles extends the refrigerant flow distance, further enhancing the uniformity of the condensation process.

[0037] Through the above technical solution, this application can dynamically adjust the distribution of gaseous refrigerant in each process, avoiding a decrease in heat transfer coefficient due to excessively low local gas phase ratio. The gaseous refrigerant continuously participates in phase change heat transfer during multiple reversal flows, significantly improving the overall efficiency of the condensation process. The synergistic effect of the distributor 500, the first baffle 410, and the second baffle 420 optimizes the refrigerant flow path, ensuring stable heat transfer performance throughout the process.

[0038] In one embodiment, one end of the diversion pipe 500 is connected to the first hot liquid inlet section 210, and the other end extends into and connects to the nth hot liquid inlet section. That is, the diversion pipe 500 passes through all the first partitions 410 and connects to all the hot liquid inlet sections, so that part of the refrigerant entering the first hot liquid inlet section 210 enters the area between the diversion pipe 500 and the hot liquid inlet channel 200, and the other part enters the diversion pipe 500 and enters the corresponding hot liquid inlet section through the diversion pipe 500.

[0039] Specifically, the manifold 500 runs through all the hot flow inlet sections and is connected to each hot flow inlet section. When the proportion of gaseous refrigerant in a certain hot flow inlet section decreases due to the condensation process, gaseous refrigerant in the adjacent inlet section can be replenished to that hot flow inlet section through the connecting hole 510 in the manifold 500, so as to avoid a sudden drop in heat exchange efficiency in a local area due to insufficient gas phase.

[0040] Compared with existing technologies, this solution connects all hot liquid inlet sections through the 500 diverter pipe, breaking the physical barriers between processes and enabling the gaseous refrigerant to dynamically adjust its distribution according to the actual needs of each section, thereby optimizing the phase change heat utilization efficiency of the condensation process.

[0041] However, this is not the only possibility. In other embodiments, the diverter 500 may also connect to a portion of the hot flow inlet section. For example, when the number of hot flow inlet sections is equal to four, the diverter 500 may only connect to the first hot flow inlet section 210 and the second hot flow inlet section 220 near the inlet end of the hot flow inlet channel 200 (meaning the fluid entering includes liquid and gas). Alternatively, the diverter 500 may only connect to the third and fourth hot flow inlet sections near the outlet end of the hot flow inlet channel 200. Or, the diverter 500 may only connect to the second hot flow inlet section 220 or the third hot flow inlet section in the middle portion.

[0042] In one embodiment, along the direction from the inlet end to the outlet end of the diverter 500, the connection area between the diverter 500 and the corresponding hot flow inlet section tends to increase. The connection area between the diverter 500 and the corresponding hot flow inlet section refers to the total area of ​​all the connecting holes 510 between the diverter 500 and the corresponding hot flow inlet section. That is, the total connection area can be increased by increasing the diameter of a single connecting hole 510, by increasing the number of connecting holes 510, or by a combination of the two.

[0043] Specifically, when the two-phase refrigerant enters from the inlet of the distributor 500, the liquid phase proportion gradually increases while the gas phase proportion decreases as the flow direction progresses. By increasing the total area of ​​the connecting hole 510 along the flow direction, the flow resistance of the downstream hot flow inlet section is relatively reduced, prompting more refrigerant to enter the subsequent hot flow inlet sections, thereby maintaining a balanced distribution of refrigerant flow in each hot flow inlet section. This structure ensures that the gas-liquid mixed refrigerant is evenly distributed in multiple circuits, avoiding a sharp drop in heat transfer coefficient due to insufficient local gas phase. In summary, this solution, by directionally adjusting the area of ​​the connecting hole 510 and actively matching the refrigerant phase change pattern, solves the problem of heat transfer efficiency degradation caused by gas phase deficiency at the end of the process.

[0044] In one embodiment, the annular channel between the diversion pipe 500 and the inner wall of the corresponding hot flow inlet section is defined as the main flow channel. The flow area A of the diversion pipe 500 and the flow area B of the main flow channel satisfy 0.02≤A / (A+B)≤0.5. Specifically, A / (A+B) can be 0.02, 0.05, 0.1, 0.2, 0.3, 0.4 or 0.5. Preferably, A / (A+B) equals 0.2.

[0045] Through the above technical solution, this application effectively solves the problem of reduced heat transfer coefficient caused by the decrease in gas phase mass fraction during the condensation process of refrigerant. By adjusting the flow area ratio of the split pipe 500 to the main flow channel, the active control of the gas-liquid two-phase flow state is achieved, thereby extending the effective heat transfer path and improving the overall heat transfer performance.

[0046] In one embodiment, there are multiple connecting holes 510, which are evenly distributed on the wall of the diversion pipe 500. Specifically, the connecting holes 510 can be evenly distributed along the circumference of the diversion pipe 500 or evenly distributed along the axial direction of the diversion pipe 500.

[0047] In one embodiment, the manifold 500 is disposed within the hot liquid inlet channel 200, and the height difference H between the inlet end face of the manifold 500 and the inlet end face of the hot liquid inlet channel 200 satisfies H ≤ 2mm. That is, when the preset height direction is vertical, the inlet end face of the manifold 500 can be higher than the inlet end face of the hot liquid inlet channel 200, but the height difference does not exceed 2mm; alternatively, the inlet end face of the manifold 500 can be lower than the inlet end face of the hot liquid inlet channel 200, and the height difference also does not exceed 2mm.

[0048] Specifically, the inlet faces of the manifold 500 and the hot liquid inlet channel 200 are kept highly aligned; for example, H can be 0.5 mm, 1 mm, 2 mm, or smaller. Because the height difference is limited to a small range, the flow cross-section of the refrigerant at the inlet of the manifold 500 changes gradually, thereby reducing the separation phenomenon caused by the inertial difference between the gas and liquid phases. This allows the gaseous refrigerant to be distributed more evenly to the manifold 500 and the hot liquid inlet channel 200, reducing the impact of localized gas phase enrichment on heat exchange efficiency.

[0049] Example 1

[0050] like Figures 2-4 As shown, in this embodiment, the plate heat exchanger further includes a flow-limiting sleeve 600 and a sealing cover 700. The flow-limiting sleeve 600 is sleeved on the outer periphery of the distribution pipe 500 and sealed through the first partition plate 410. The inner wall of the flow-limiting sleeve 600 is spaced apart from the outer wall of the distribution pipe 500, and the outer wall of the flow-limiting sleeve 600 is spaced apart from the inner wall of the hot liquid inlet channel 200. The sealing cover 700 is sealed over the inlet end of the region between the flow-limiting sleeve 600 and the inner wall of the hot liquid inlet channel 200, so that the refrigerant (including gaseous refrigerant and liquid refrigerant) at the inlet end of the hot liquid inlet channel 200 enters the distribution pipe 500 and the region between the outer wall of the distribution pipe 500 and the inner wall of the flow-limiting sleeve 600, respectively. Furthermore, the sealing cover 700 can also support the connection between the flow-limiting sleeve 600 and the hot liquid inlet channel 200. The inner wall of the liquid channel 200, the diversion pipe 500, the flow-limiting sleeve 600, and the inner wall of the hot flow inlet channel 200 (one of the core plates 150) are connected by a first partition 410. Specifically, the first partition 410 includes a first partition 411 and a second partition 412. The core plate 150 extends toward the outer wall of the flow-limiting sleeve 600 to form the first partition 411. The first partition 411 separates (mainly by welding, but can also be by snap-fit) the area between the inner wall of the hot flow inlet channel 200 and the outer wall of the flow-limiting sleeve 600. The second partition 412 separates (mainly by welding, but can also be by snap-fit) the area between the inner wall of the flow-limiting sleeve 600 and the outer wall of the diversion pipe 500. That is, the flow-limiting sleeve 600 is sealed between the first partition 411 and the second partition 412.

[0051] Specifically, the core plate 150 forms alternating hot flow layers 160 and cold flow layers 170 through a corrugated structure. A flow-limiting sleeve 600 and a flow divider 500 are installed within the hot flow inlet channel 200 to form a double-ring flow channel. A first partition 411 extends directly from the core plate 150 to the outer wall of the flow-limiting sleeve 600, dividing the annular region between the inner wall of the hot flow inlet channel 200 and the outer wall of the flow-limiting sleeve 600 into independent sections. A second partition 412 divides the annular region between the inner wall of the flow-limiting sleeve 600 and the outer wall of the flow divider 500 into independent sections. This achieves stratified flow of the refrigerant within the double-ring flow channel, ensuring that refrigerants of different processes flow independently within their corresponding annular regions.

[0052] It should be noted that the bottom of the flow-limiting sleeve 600 (the end furthest from the inlet) and the bottom of the diverter 500 can be sealed separately. They can be sealed by the same plate or sealed separately.

[0053] Furthermore, the side wall of the flow-limiting sleeve 600 is provided with an outlet hole 610. The flow-limiting sleeve 600 is constantly connected to the hot liquid inlet channel 200 through the outlet hole 610. The diverter pipe 500 can connect the area between the inner side wall of the hot liquid inlet channel 200 and the outer side wall of the flow-limiting sleeve 600 through the connecting hole 510 and the outlet hole 610 in sequence. It should be noted that both the diverter pipe 500 and the flow-limiting sleeve 600 are set inside the hot liquid inlet channel 200. Therefore, theoretically, the internal space of the diverter pipe 500 and the internal space of the flow-limiting sleeve 600 are both within the hot liquid inlet channel 200. All spaces belong to the hot flow inlet channel 200. However, for ease of description, in this application, when the sealing area of ​​the first partition 410 is used as the dividing point, the hot flow inlet channel 200 mainly refers to the area between the outer wall of the diverter pipe 500 and the inner wall of the hot flow inlet channel 200. When distinguishing between the inner space of the flow-limiting sleeve 600 and the area of ​​the hot flow inlet channel 200 connected to the hot flow layer 160, the hot flow inlet channel 200 can also specifically refer to the area between the outer wall of the flow-limiting sleeve 600 and the inner wall of the hot flow inlet channel 200.

[0054] Thus, taking the example of one first partition 410 and one second partition 420, the first part of the refrigerant (including gaseous and liquid refrigerant) passes through the area between the diverter 500 and the flow-limiting sleeve 600, through the outlet hole 610, and enters the area between the flow-limiting sleeve 600 and the first hot flow inlet section 210. Then, the refrigerant enters the corresponding hot flow layers 160, and then enters the first hot flow outlet section 310 through the hot flow layers 160. Then, it detours through the next level of hot flow layers 160 to enter the area between the second hot flow inlet section 220 and the flow-limiting sleeve 600. Then, it detours through the next level of hot flow layers 160 to enter the second hot flow outlet section 320, and finally leaves the plate heat exchanger. The second part of the refrigerant (including gaseous and liquid refrigerant) enters the flow-limiting sleeve 600 through the diversion pipe 500 and the connecting hole 510 in sequence. Then, it enters the area between the second hot flow inlet section 220 and the flow-limiting sleeve 600 through the outlet hole 610, and merges with the first part of the refrigerant. After that, the merged first and second parts of the refrigerant enter the second hot flow outlet section 320 through each hot flow layer 160, and finally leave the plate heat exchanger.

[0055] Specifically, after the refrigerant enters the inlet end of the hot flow inlet channel 200, it is blocked by the sealing cap 700 and divided into two streams, which enter the interior of the distribution pipe 500 and the first flow channel 230 between the distribution pipe 500 and the flow-limiting sleeve 600, respectively. By adjusting the distance between the flow-limiting sleeve 600 and the distribution pipe 500 and the hot flow inlet channel 200, the flow ratio of the two refrigerant streams can be controlled. The first baffle 410 divides the hot flow inlet channel 200 into multiple inlet sections and connects with the flow-limiting sleeve 600 and the distribution pipe 500 to form a sealed structure, ensuring that the refrigerant flows along a preset path.

[0056] Through the above technical solution, this application achieves dynamic diversion control of refrigerant in multiple processes, effectively balancing the distribution state of gas-liquid two-phase refrigerant in different processes, mitigating the decreasing trend of heat transfer coefficient as the process progresses, and improving the overall heat transfer efficiency of the condensation process. Furthermore, the flow-limiting sleeve 600 reduces the flow rate of gaseous refrigerant and increases the proportion of gaseous refrigerant entering the diversion pipe 500.

[0057] In one embodiment, the annular channel between the diversion pipe 500 and the flow-limiting sleeve 600 is defined as the first flow channel 230. The flow area A of the diversion pipe 500 and the flow area C of the first flow channel 230 satisfy 0.1≤A / (A+C)≤0.5. Specifically, A / (A+C) can be 0.1, 0.2, 0.3, 0.4 or 0.5. Preferably, A / (A+C) is equal to 0.3.

[0058] Through the above technical solution, this application can achieve dynamic separation and distribution of gaseous and liquid refrigerant during the process advancement, maintaining a stable proportion of gaseous refrigerant in each heat flow layer 160. When the refrigerant enters the downstream process, gaseous refrigerant is continuously replenished to the corresponding heat flow inlet section through the diversion pipe 500, effectively alleviating the problem of heat transfer coefficient decay caused by the decrease in gas phase mass fraction.

[0059] In one embodiment, there are multiple outlet holes 610, which are evenly distributed on the pipe wall of the flow-limiting sleeve 600. Specifically, the outlet holes 610 can be evenly distributed along the circumference of the flow-limiting sleeve 600 or evenly distributed along the axial direction of the flow-limiting sleeve 600.

[0060] Example 2

[0061] like Figures 5-6As shown, in this embodiment, the plate heat exchanger also includes a flow-limiting cover 800, which covers (mainly welded, but can also be snap-fitted) the inlet end of the region between the distribution pipe 500 and the inner wall of the hot liquid inlet channel 200. The flow-limiting cover 800 has one or more flow-limiting holes 810, so that the refrigerant (including gaseous refrigerant and liquid refrigerant) at the inlet end of the hot liquid inlet channel 200 enters the region between the distribution pipe 500 and the inner wall of the hot liquid inlet channel 200 through the flow-limiting holes 810.

[0062] Specifically, when the refrigerant enters from the inlet end of the hot flow inlet channel 200, the flow restrictor 800 prevents the refrigerant from flowing directly to the outer area of ​​the distribution pipe 500, forcing the refrigerant to preferentially enter the annular area between the distribution pipe 500 and the inner wall of the channel through the flow restrictor 810. The size and distribution of the flow restrictor 810 can control the flow rate and pressure distribution of the refrigerant within the annular area; for example, a tapered orifice design can balance the flow distribution in different height areas.

[0063] In some specific implementations, the flow restrictor 800 can be designed as a detachable structure, which facilitates the replacement of flow restrictor 810 plates with different orifice diameters according to the working conditions.

[0064] Furthermore, in one embodiment, a plurality of flow-limiting orifices 810 are evenly spaced around the axis of the flow divider 500.

[0065] Example 3

[0066] In this embodiment, the plate heat exchanger further includes a flow-limiting tube and a sealing cap. The flow-limiting tube is inserted inside the flow divider 500. The outer wall of the flow-limiting tube is spaced apart from the inner wall of the flow divider 500. The outer wall of the flow divider 500 is spaced apart from the inner wall of the hot liquid inlet channel 200. The sealing cap is sealed at the inlet end of the region between the flow divider 500 and the inner wall of the hot liquid inlet channel 200, so that the refrigerant at the inlet end of the hot liquid inlet channel 200 can enter the flow-limiting tube and the region between the inner wall of the flow divider 500 and the outer wall of the flow-limiting tube, respectively. The flow-limiting tube, the flow divider 500 and the inner wall of the hot liquid inlet channel 200 are connected by a first partition 410.

[0067] The flow-limiting cannula has a flow hole on its side wall. The flow-limiting cannula is connected to the shunt tube 500 through the flow hole. The flow-limiting cannula can connect the area between the inner side wall of the hot liquid inlet channel 200 and the outer side wall of the shunt tube 500 through the flow hole and the connecting hole 510 in sequence.

[0068] It should be noted that the function of the flow-limiting tube in this embodiment is the same as that of the flow-limiting sleeve 600 in Embodiment 1, both serving to limit the refrigerant flow rate. The difference lies in their placement. Thus, the refrigerant participating in the first process of condensation heat exchange enters the heat flow layer 160 from the inner cavity of the flow-limiting tube through the flow hole, the connecting hole 510, and the hot flow inlet channel 200. The gaseous refrigerant participating in the second process of heat exchange flows in from the area between the inner wall of the branch pipe 500 and the outer wall of the flow-limiting tube.

[0069] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0070] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the scope of protection of this application should be determined by the appended claims.

[0071] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application 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, and therefore should not be construed as a limitation of this application.

[0072] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0073] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0074] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0075] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0076] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

Claims

1. A plate heat exchanger, characterized in that, The plate heat exchanger is provided with a hot flow inlet channel (200), a hot flow outlet channel (300), a cold flow inlet channel, a cold flow outlet channel, a hot flow layer (160), and a cold flow layer (170). The hot flow layer (160) and the cold flow layer (170) are alternately distributed along the preset height direction of the plate heat exchanger. The cold flow inlet channel, each of the cold flow layers (170) and the cold flow outlet channel are connected in sequence. The plate heat exchanger includes a first partition (410), a second partition (420), and a flow divider (500). The first partition (410) is spaced apart along a preset height direction in the heat inlet channel (200) to divide the heat inlet channel (200) into multiple heat inlet sections arranged sequentially along the preset height direction. The second partition (420) is spaced apart along a preset height direction in the heat outlet channel (300) to divide the heat outlet channel (300) into multiple heat outlet sections arranged sequentially along the preset height direction. Along the preset height direction, the first partition (410) and the second partition (420) are staggered so that the hot liquid inlet section, the hot liquid layer (160) and the hot liquid outlet section are sequentially circulated and connected to form a refrigerant flow structure with multiple detours. The diversion pipe (500) is sequentially installed through multiple hot liquid inlet sections. The inner walls of the diversion pipe (500) and the hot liquid inlet sections are spaced apart. The side wall of the diversion pipe (500) is provided with a connecting hole (510) that connects to the corresponding hot liquid inlet section, so that at least part of the gaseous refrigerant in one of the hot liquid inlet sections can enter another hot liquid inlet section through the diversion pipe (500).

2. The plate heat exchanger according to claim 1, characterized in that, The shunt pipe (500) connects all of the hot flow inlet sections.

3. The plate heat exchanger according to claim 1 or 2, characterized in that, Along the direction from the inlet end to the outlet end of the diversion pipe (500), the total area of ​​the diversion pipe (500) and the connecting hole (510) between the corresponding hot liquid inlet section tends to increase.

4. The plate heat exchanger according to claim 1, characterized in that, The annular channel between the diversion pipe (500) and the inner wall of the hot flow inlet section is defined as the main channel. The flow area A of the diversion pipe (500) and the flow area B of the main channel satisfy 0.02≤A / (A+B)≤0.

5.

5. The plate heat exchanger according to claim 1, characterized in that, The diverter pipe (500) is disposed in the hot liquid inlet channel (200), and the height difference H between the end face of the diverter pipe (500) and the end face of the hot liquid inlet channel (200) satisfies that H≤2mm.

6. The plate heat exchanger according to claim 1, characterized in that, It also includes a flow-limiting sleeve (600) and a sealing cap (700). The flow-limiting sleeve (600) is sleeved on the outer periphery of the diversion pipe (500) and sealed through the first partition plate (410). The inner wall of the flow-limiting sleeve (600) is spaced apart from the outer wall of the diversion pipe (500), and the outer wall of the flow-limiting sleeve (600) is spaced apart from the inner wall of the hot liquid inlet channel (200). The sealing cap (700) is sealed and covered by the flow-limiting sleeve. The inlet end of the region between the hot liquid inlet channel (200) and the inner wall of the hot liquid inlet channel (200) is provided so that the refrigerant at the inlet end of the hot liquid inlet channel (200) can enter the branch pipe (500) and the region between the outer wall of the branch pipe (500) and the inner wall of the flow limiting sleeve (600). The branch pipe (500), the flow limiting sleeve (600) and the inner wall of the hot liquid inlet channel (200) are connected by the first partition (410). The side wall of the flow-limiting sleeve (600) is provided with an outlet hole (610). The flow-limiting sleeve (600) is connected to the hot liquid inlet channel (200) through the outlet hole (610). The diverter pipe (500) can connect the area between the inner side wall of the hot liquid inlet channel (200) and the outer side wall of the flow-limiting sleeve (600) through the connecting hole (510) and the outlet hole (610) in sequence.

7. The plate heat exchanger according to claim 6, characterized in that, It also includes a core plate (150), adjacent to the core plate (150) forming the hot flow layer (160) and the cold flow layer (170), the first partition (410) includes a first partition (411) and a second partition (412), the core plate (150) extends toward the outer wall of the flow-limiting sleeve (600) to form the first partition (411), the first partition (411) separates the area between the inner wall of the hot flow inlet channel (200) and the outer wall of the flow-limiting sleeve (600), and the second partition (412) separates the area between the inner wall of the flow-limiting sleeve (600) and the outer wall of the diversion pipe (500).

8. The plate heat exchanger according to claim 6, characterized in that, The annular channel between the diverter (500) and the flow-limiting sleeve (600) is defined as the first flow channel (230). The flow area A of the diverter (500) and the flow area C of the first flow channel (230) satisfy 0.1≤A / (A+C)≤0.

5.

9. The plate heat exchanger according to claim 1, characterized in that, It also includes a flow-limiting cover (800), which covers the inlet end of the region between the flow divider (500) and the inner wall of the hot flow inlet channel (200). The flow-limiting cover (800) is provided with a flow-limiting hole (810) so that the refrigerant at the inlet end of the hot flow inlet channel (200) can enter the region between the flow divider (500) and the inner wall of the hot flow inlet channel (200) through the flow-limiting hole (810).

10. The plate heat exchanger according to claim 1, characterized in that, It also includes a flow-limiting tube and a sealing cap. The flow-limiting tube is inserted inside the shunt tube (500). The outer wall of the flow-limiting tube is spaced apart from the inner wall of the shunt tube (500). The outer wall of the shunt tube (500) is spaced apart from the inner wall of the hot liquid inlet channel (200). The sealing cap is sealed at the inlet end of the region between the shunt tube (500) and the inner wall of the hot liquid inlet channel (200) so that the refrigerant at the inlet end of the hot liquid inlet channel (200) can enter the flow-limiting tube and the region between the inner wall of the shunt tube (500) and the outer wall of the flow-limiting tube, respectively. The flow-limiting tube, the shunt tube (500) and the inner wall of the hot liquid inlet channel (200) are connected by the first partition (410). The flow-limiting tube has a flow hole on its side wall. The flow-limiting tube is connected to the diversion tube (500) through the flow hole. The flow-limiting tube can connect the area between the inner side wall of the hot liquid inlet channel (200) and the outer side wall of the diversion tube (500) in sequence through the flow hole and the connecting hole (510).

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