A full counterflow heat exchange device and a swimming pool heat pump system with the same

Abstract

The utility model relates to heat exchange technical field discloses a kind of full reverse flow heat exchange device and the swimming pool heat pump system with it.Full reverse flow heat exchange device, comprising: installation shell, heat exchange cavity is arranged in it, fluid inlet and fluid outlet are provided on installation shell, fluid inlet and fluid outlet are respectively arranged in the two ends of installation shell along length direction;Coil assembly is installed in installation shell, coil assembly includes inner ring coil and outer ring coil, inner ring coil is arranged around the axis of installation shell, outer ring coil is arranged around inner ring coil, first inlet and first outlet are provided on inner ring coil, second inlet and second outlet are provided on outer ring coil, two kinds of heat exchange fluid pass through full reverse flow, can increase the average heat exchange temperature difference between fluid, improve overall heat exchange efficiency.Meanwhile also can avoid effusion of working fluid in the bottom of heat exchange cavity, ensure that effective heat exchange area on coil assembly can be fully utilized, reduce heat exchange dead zone, realize the optimization of energy efficiency.

Description

Technical Field

[0001] This utility model relates to the field of heat exchange technology, specifically to a full countercurrent heat exchange device and a swimming pool heat pump system having the same. Background Technology

[0002] Heat pumps, as highly efficient and energy-saving heating systems, are increasingly widely used in fields such as swimming pool temperature control, industrial refrigeration, and commercial hot water. Among them, titanium tube heat exchangers, due to their excellent corrosion resistance and biocompatibility, have become the core heat exchange component for treating chlorinated water or corrosive working fluids.

[0003] Titanium tube heat exchangers are primarily used as condensers in swimming pool heat pump units. Existing titanium tube heat exchangers typically employ a single-layer spiral coil design. The refrigerant side uses a "top-in, top-out" arrangement, meaning the refrigerant enters from the top of the coil, exchanges heat inside, and then flows back to the top to exit. The water side uses a "bottom-in, top-out" arrangement, allowing cooling water to flow upwards across the outer surface of the coil for heat exchange. However, to ensure the smooth discharge of the condensed liquid refrigerant, a certain liquid level needs to be maintained within the heat exchanger. This results in the lower coil being submerged in liquid refrigerant, reducing the effective heat exchange area and consequently decreasing the overall heat exchange capacity of the heat exchanger. Furthermore, the compact space layout of swimming pool heat pump units limits the height of the titanium tube heat exchanger, further exacerbating the problem of reduced heat exchange capacity. Utility Model Content

[0004] In view of this, the present invention provides a fully countercurrent heat exchange device and a swimming pool heat pump system having the same, so as to solve the problem of limited heat exchange capacity of titanium tube heat exchangers in existing swimming pool heat pumps.

[0005] In a first aspect, this utility model provides a fully countercurrent heat exchange device, comprising: The mounting housing has a heat exchange chamber inside, and a fluid inlet and a fluid outlet are provided on the mounting housing. The fluid inlet and the fluid outlet are respectively located at both ends of the mounting housing along its length. A coil assembly is installed inside the mounting housing. The coil assembly includes an inner coil and an outer coil. The inner coil is arranged around the axis of the mounting housing, and the outer coil is arranged around the inner coil. The inner coil is provided with a first inlet and a first outlet, and the outer coil is provided with a second inlet and a second outlet. The first outlet and the second outlet penetrate through the end of the mounting housing where the fluid inlet is provided, and the first inlet and the second inlet penetrate through the end of the mounting housing where the fluid outlet is provided.

[0006] The counter-current heat exchanger is used in swimming pool heat pump systems. Water, used for heat exchange, circulates within the heat exchange chamber, while the refrigerant, used for heat exchange, circulates within the coil assembly. During operation, water, the working fluid, enters the heat exchange chamber through the fluid inlet of the mounting shell and flows along the length of the shell towards the fluid outlet. Simultaneously, the refrigerant, another working fluid, enters the coil assembly through the first inlet of the inner coil and the second inlet of the outer coil, flowing within the inner and outer coils respectively, and finally exiting through the first and second outlets. Because the first and second outlets are located at one end of the fluid inlet and the first and second inlets at the other end, the two working fluids form a completely counter-current flow path within the heat exchange chamber. One working fluid flows from the fluid inlet to the fluid outlet outside the coil, while the other flows from the fluid outlet to the fluid inlet inside the coil, thus achieving highly efficient counter-current heat exchange. Counter-flow heat exchangers, employing a method of inner and outer coil windings, do not increase the overall height of the heat exchange unit, allowing for easy installation within compact pool heat pump units. Furthermore, the counter-flowing of the two working fluids increases the average temperature difference between them, thereby improving overall heat exchange efficiency. Additionally, the counter-flowing nature of the two working fluids prevents liquid accumulation at the bottom of the heat exchange chamber, ensuring full utilization of the effective heat exchange area on the coil assembly, reducing dead zones, and optimizing energy efficiency within a limited space.

[0007] In one alternative implementation, the first outlet and the second inlet are connected in series via a cooperating flow channel, or the second outlet and the first inlet are connected in series via a cooperating flow channel.

[0008] The refrigerant first flows through the outer coil, exits from the second outlet of the outer coil, then enters the first inlet of the inner coil through a matching flow channel, and finally exits from the first outlet of the inner coil. Alternatively, the refrigerant first flows through the inner coil, exits from the first outlet of the inner coil, then enters the second inlet of the outer coil through a matching flow channel, and finally exits from the second outlet of the outer coil. Throughout the process, the water flow maintains a flow direction from the fluid inlet to the fluid outlet of the mounting shell, forming a counter-current flow with the refrigerant flow within the coil assembly. Connecting the inner and outer coils in series extends the refrigerant flow path, increases the heat exchange time within the coil assembly, and is suitable for applications requiring greater subcooling, while maintaining a full counter-current heat exchange characteristic and a high heat exchange temperature difference.

[0009] In one alternative implementation, the first inlet and the second inlet are connected in parallel to an external refrigerant supply device.

[0010] After flowing out from the external refrigerant supply equipment, the refrigerant is simultaneously distributed to the first inlet of the inner coil and the second inlet of the outer coil. The refrigerant flows in parallel from top to bottom within both the inner and outer coils, finally converging at the first and second outlets respectively before being discharged. The parallel connection of the inner and outer coils reduces refrigerant flow resistance, improves refrigerant distribution uniformity, and allows both coils to perform heat exchange simultaneously. This results in a larger effective heat exchange area for the same refrigerant flow rate, thereby improving overall heat exchange efficiency.

[0011] In one optional embodiment, the inner coil diameter is 30% to 40% of the inner diameter of the mounting housing, so that the inner coil is tightly arranged in the central region of the heat exchange chamber; the outer coil diameter is 70% to 80% of the inner diameter of the mounting housing, so that the outer coil makes full use of the annular area near the inner wall of the mounting housing, allowing the two working fluids to exchange heat in countercurrent between the inner and outer coils arranged within a specific diameter range, eliminating the "heat exchange dead zone" formed in the central region by traditional single coils, thereby improving the space utilization inside the mounting housing and the overall heat exchange performance of the heat exchange device.

[0012] In one optional embodiment, the inner coil has a winding spacing of 2mm-4mm, and the outer coil has a winding spacing not less than that of the inner coil. The smaller spacing of the inner coil enhances the turbulence of the water flow in the central area, while the appropriately increased spacing of the outer coil ensures a suitable cross-sectional area for water flow, preventing excessive resistance and ensuring the uniformity and stability of the water flow distribution throughout the heat exchange chamber. This synergistically improves the overall heat exchange capacity of the heat exchange device.

[0013] In one alternative embodiment, the ratio of the total length of the inner coil to the total length of the outer coil is 0.8 to 1.0.

[0014] When refrigerant flows through parallel or series-connected inner and outer coils, the similar lengths of both result in a more balanced refrigerant flow distribution and matched flow resistance characteristics. By controlling the total length ratio of the inner and outer coils, the natural distribution of refrigerant in the inner and outer flow paths is optimized, avoiding flow imbalances or uneven resistance caused by excessively long or short pipes in one path. This ensures that the heat exchange capacity of the inner and outer coils is utilized synchronously and fully, achieving optimal overall heat exchange performance while maintaining a constant total amount of tubing.

[0015] In one alternative embodiment, a supporting inner cylinder is further included, which is installed inside the mounting housing, and the inner coil is wound around and fixed to the outer side wall of the supporting inner cylinder.

[0016] The inner support cylinder is fixedly installed inside the mounting housing. The inner coil is directly wound around and fixed to the outer wall of the inner support cylinder, thereby obtaining stable support and positioning through the inner support cylinder, preventing the inner coil from deforming or displacing due to fluid impact or vibration, and enhancing the mechanical stability and reliability of the entire coil assembly.

[0017] In one alternative embodiment, the inner support cylinder, the inner coil, and the outer coil are coaxially mounted.

[0018] This design ensures a more stable and uniform flow of the working fluid as it passes through the annular flow channel formed by the supporting inner cylinder, inner coil, and outer coil. It avoids the generation of flow deviations or localized eddies, promoting uniform heat transfer and reducing flow resistance, thereby further improving heat transfer efficiency.

[0019] In one alternative embodiment, the end of the supporting inner cylinder facing the fluid outlet is closed.

[0020] When the working fluid enters the mounting housing from the fluid inlet, the closed end of the inner support cylinder forces the fluid to flow entirely through the annular heat exchange space formed by the inner and outer coils outside the inner support cylinder, preventing it from being directly discharged from the fluid outlet through the inner support cylinder. This ensures that all fluid can fully exchange heat with the coil assembly, improving the utilization rate of the heat exchange medium and the overall effective heat exchange efficiency of the device.

[0021] Secondly, this utility model also provides a swimming pool heat pump system, including the full countercurrent heat exchange device described in this application.

[0022] Since the pool heat pump system includes a full counter-current heat exchanger, it has the same effect as the full counter-current heat exchanger, so it will not be elaborated here. Attached Figure Description

[0023] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 A schematic diagram of the structure of the all-counterflow heat exchanger provided in the embodiment of this utility model.

[0025] Figure 2 This is a schematic diagram of the structure of the coil assembly provided in an embodiment of the present utility model.

[0026] Figure 3This is a schematic diagram of the structure of the inner and outer coils connected in series, provided for an embodiment of the present invention.

[0027] Figure 4 This is a schematic diagram of the structure in which the inner and outer coils are connected in parallel, as provided in an embodiment of the present invention.

[0028] Explanation of reference numerals in the attached drawings: 1. Mounting housing; 101. Top cover; 102. Outer cylinder; 103. Base; 104. Fluid inlet; 105. Fluid outlet; 2. Coil assembly; 201. Inner coil; 2011. First inlet; 2012. First outlet; 202. Outer coil; 2021. Second inlet; 2022. Second outlet; 3. Supporting inner cylinder. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0030] The following is combined Figures 1 to 4 The following describes embodiments of the present invention.

[0031] According to an embodiment of the present invention, a full countercurrent heat exchange device is provided, including a mounting housing 1 and a coil assembly 2 disposed inside the mounting housing 1.

[0032] The mounting housing 1 has a heat exchange chamber inside for containing the working fluid and exchanging heat. The wall of the mounting housing 1 is provided with a fluid inlet 104 for the working fluid to enter the heat exchange chamber and a fluid outlet 105 for the working fluid to leave the heat exchange chamber. The fluid inlet 104 and fluid outlet 105 are respectively arranged at both ends of the mounting housing 1 along its length, thereby ensuring that the working fluid can form an axial flow path within the heat exchange chamber.

[0033] The coil assembly 2 is fixedly installed inside the heat exchange cavity of the mounting housing 1. The coil assembly 2 consists of an inner coil 201 and an outer coil 202. The inner coil 201 is arranged around the central axis of the mounting housing 1 in the central region of the heat exchange cavity. The outer coil 202 is arranged around the outer side of the inner coil 201 in the peripheral region of the heat exchange cavity. The outer coil 202 is concentrically arranged with the inner coil 201, thus forming a double-layer coil structure in the radial direction. The two ends of the inner coil 201 are respectively the first inlet 2011 for the cooling medium to enter and the first outlet 2012 for the cooling medium to exit. The two ends of the outer coil 202 are respectively the second inlet 2021 for the cooling medium to enter and the second outlet 2022 for the cooling medium to exit. The first outlet 2012 and the second outlet 2022 both penetrate the end of the mounting housing 1 that is provided with a fluid inlet 104 and extend to the outside of the mounting housing 1. The first inlet 2011 and the second inlet 2021 both penetrate the end of the mounting housing 1 where the fluid outlet 105 is provided and extend to the outside of the mounting housing 1.

[0034] In one specific application scenario of this embodiment, the full counter-current heat exchange device is applied to a swimming pool heat pump system. The heat exchange chamber contains water, which participates in heat exchange, while the coil assembly 2 contains a cooling or heating medium.

[0035] Specifically, during the operation of the counter-current heat exchanger, water enters the heat exchange chamber through the fluid inlet 104 of the mounting housing 1 and flows along the length of the mounting housing 1 towards the fluid outlet 105. Simultaneously, the refrigerant enters the coil assembly 2 through the first inlet 2011 of the inner coil 201 and the second inlet 2021 of the outer coil 202. The refrigerant entering the inner coil 201 flows along the tube side of the inner coil 201, and the refrigerant entering the outer coil 202 flows along the tube side of the outer coil 202. Finally, the refrigerant that has completed heat exchange in the inner coil 201 is discharged from the first outlet 2012, and the refrigerant that has completed heat exchange in the outer coil 202 is discharged from the second outlet 2022. Since the first outlet 2012 and the second outlet 2022 are located at the end of the mounting housing 1 where the fluid inlet 104 is located, and the first inlet 2011 and the second inlet 2021 are located at the end of the mounting housing 1 where the fluid outlet 105 is located, the two working fluids form an overall counter-current flow path inside the heat exchange chamber. Water flows from the fluid inlet 104 to the fluid outlet 105 outside the coil assembly 2, while the cooling medium flows from the fluid outlet 105 to the fluid inlet 104 inside the coil assembly 2, achieving efficient counter-current heat exchange.

[0036] The counter-current heat exchanger provided in this embodiment uses an outer coil 202 surrounding an inner coil 201, eliminating the need to increase the axial height of the mounting housing 1. This allows the counter-current heat exchanger to be easily installed inside a compact pool heat pump unit, improving the equipment's space adaptability. Because the two working fluids flow in opposite directions, the average heat exchange temperature difference between water and the cooling medium is increased, effectively improving the overall heat exchange efficiency of the counter-current heat exchanger. Furthermore, the completely counter-current flow between water and the cooling medium, along with the cooling medium flowing from top to bottom, effectively prevents the accumulation of cooling medium at the bottom of the heat exchange chamber. This ensures that the surfaces of both the inner and outer coils 201 and 202 are fully utilized as effective heat exchange areas, reducing dead zones and optimizing energy efficiency within a limited space.

[0037] In one embodiment, the first outlet 2012 and the second inlet 2021 are connected in series via a cooperating flow channel, or the second outlet 2022 and the first inlet 2011 are connected in series via a cooperating flow channel.

[0038] Specifically, when the outer coil 202 and the inner coil 201 are arranged in series, the refrigerant first enters the second inlet 2021 of the outer coil 202 from the end of the mounting housing 1 where the fluid outlet 105 is provided, and flows downward along the tube side of the outer coil 202. After completing the main condensation heat exchange in the outer coil 202, the liquid refrigerant flows out from the second outlet 2022 of the outer coil 202. Subsequently, the liquid refrigerant is guided to the first inlet 2011 of the inner coil 201 through the matching flow channel, and continues to flow downward in the inner coil 201, where it is further subcooled. Finally, the refrigerant that has completed the heat exchange process is discharged from the first outlet 2012 of the inner coil 201 from the mounting housing 1.

[0039] Alternatively, the inner coil 201 can be connected in series with the outer coil 202 following, meaning the refrigerant flows through the inner coil 201 first, and then through the outer coil 202. Throughout the series operation, the water flow direction remains from the fluid inlet 104 to the fluid outlet 105 of the mounting housing 1. The water flows upward outside the pipes, forming a complete counter-current flow with the refrigerant flow direction inside the coil assembly 2.

[0040] The series connection of the inner coil 201 and the outer coil 202 can significantly extend the overall flow of the refrigerant and increase the heat exchange time of the refrigerant in the coil assembly 2. It is particularly suitable for refrigeration or heat pump operations that require greater subcooling. At the same time, it maintains the full counterflow heat exchange characteristics, maintains a high heat exchange temperature difference, and ensures that the heat exchange efficiency will not decrease due to the extension of the flow.

[0041] The flow channel can be made of rigid or flexible connecting pipes, or it can be a channel formed inside a structure such as a wall that allows fluid to pass through. When the flow channel is made of rigid connecting pipe, it can be made of the same material as the coil assembly 2 or a different corrosion-resistant material. The connection method can be welding, threaded connection or quick coupling connection.

[0042] In one embodiment, the first inlet 2011 and the second inlet 2021 are connected in parallel via a diversion device and are connected to an external refrigerant supply device. After the refrigerant flows out from the external refrigerant supply device, it is distributed by the diversion device to the first inlet 2011 of the inner coil 201 and the second inlet 2021 of the outer coil 202. The refrigerant flows in parallel from top to bottom in the inner coil 201 and the outer coil 202, exchanging heat with the water flow outside the coil in its respective tube pass. After heat exchange, the refrigerant is finally collected from the first outlet 2012 and the second outlet 2022 and discharged from the mounting housing 1.

[0043] The flow distribution device can be a Y-type tee, T-type tee, or distributor, etc., capable of flow distribution. Furthermore, independent control valves can be installed at the first inlet 2011 of the inner coil 201 and the second inlet 2021 of the outer coil 202, respectively, to adjust the flow ratio between the inner and outer coils 202 by regulating the valve opening.

[0044] The parallel connection of the inner coil 201 and the outer coil 202 can reduce the total resistance of refrigerant flow and improve the uniformity of refrigerant distribution. This allows the inner coil 201 and the outer coil 202 to perform heat exchange simultaneously, achieving a larger effective heat exchange area under the same refrigerant flow rate, thereby improving the overall heat exchange efficiency. This is particularly suitable for high-efficiency heat pump systems that are sensitive to flow resistance.

[0045] In one embodiment, the inner coil 201 has a winding diameter of 30% to 40% of the inner diameter of the mounting housing 1, so that the inner coil 201 is closely arranged in the central region of the heat exchange cavity; the outer coil 202 has a winding diameter of 70% to 80% of the inner diameter of the mounting housing 1, so that the outer coil 202 makes full use of the annular region near the inner wall of the mounting housing 1.

[0046] The inner coil 201 occupies the central area with a smaller coil diameter, while the outer coil 202 occupies the peripheral area with a larger coil diameter, forming an annular flow channel space between them. The two working fluids can exchange heat in countercurrent between the inner coil 201 and the outer coil 202, which are arranged within a specific diameter range.

[0047] The diameter ratio of the inner coil 201 and the outer coil 202 can maximize the coverage of the internal area of ​​the mounting shell 1, eliminate the heat exchange dead zone formed in the central area by the traditional single coil, thereby improving the space utilization rate inside the mounting shell 1 and the overall heat exchange performance of the heat exchange device, while avoiding the edge flow short-circuit problem caused by the outer coil 202 being too close to the shell wall.

[0048] Furthermore, the winding spacing of the inner coil 201 is 2mm-4mm, and the winding spacing of the outer coil 202 is not less than that of the inner coil 201. A smaller winding spacing in the inner coil 201 enhances the turbulence in the central region, disrupts the boundary layer development of the heat exchange fluid during flow, and improves the local heat transfer coefficient. Appropriately increasing the winding spacing of the outer coil 202 ensures the cross-sectional area for water flow and avoids excessive flow resistance. The winding spacing of the outer coil 202 can be set equal to the winding spacing of the inner coil 201, or 1mm to 2mm larger. When the water velocity in the heat exchange chamber is high, the winding spacing of the inner coil 201 can be appropriately increased to reduce pressure drop; when the water velocity is low, the winding spacing of the inner coil 201 can be further reduced to enhance the turbulence effect. The spacing configuration of the tubes ensures the uniformity and stability of the water flow distribution throughout the heat exchange chamber, thereby synergistically enhancing the overall heat exchange capacity of the heat exchange device and achieving a differentiated heat exchange design that strengthens the center and balances the periphery.

[0049] In one embodiment, the ratio of the total length of the inner coil 201 to the total length of the outer coil 202 is 0.8 to 1.0.

[0050] When refrigerant flows through the inner coil 201 and outer coil 202, which are connected in parallel or series, the similar lengths of the inner and outer coils result in a more balanced refrigerant flow distribution, and the flow resistance characteristics of the inner and outer coils match. In a series arrangement, the length of the downstream coil can be appropriately extended to increase subcooling; in a parallel arrangement, the consistency of the two coil lengths must be strictly ensured to guarantee uniform flow distribution. By controlling the total length ratio of the inner coil 201 to the outer coil 202, the natural distribution of refrigerant between the inner and outer coils is optimized, avoiding flow imbalances or uneven resistance caused by one coil being too long or too short. This ensures that the heat exchange capacity of the inner coil 201 and outer coil 202 is simultaneously and fully utilized, achieving optimal overall heat exchange performance while maintaining a constant total amount of tubing, thus achieving the best balance between material usage and heat exchange effect.

[0051] In one embodiment, a supporting inner cylinder 3 is also included, which is installed inside the mounting housing 1, and the inner coil 201 is wound around and fixed on the outer wall of the supporting inner cylinder 3.

[0052] The inner support cylinder 3 is fixedly installed at the center of the mounting housing 1. The inner coil 201 is directly wound and fixed to the outer wall of the inner support cylinder 3 in a spiral manner. The inner coil 201 can be mechanically fixed to the inner support cylinder by welding, clamping, or binding, thereby obtaining stable radial support and axial positioning through the inner support cylinder 3. The inner support cylinder 3 can be made of stainless steel pipe, engineering plastic pipe, or composite material pipe, and its wall thickness is determined according to the strength requirements.

[0053] Furthermore, a spiral groove can be pre-machined on the outer wall of the inner support cylinder 3, and the inner coil 201 is embedded in the spiral groove to achieve positioning; or axially extending positioning ribs can be provided on the outer wall of the inner support cylinder 3, and the inner coil 201 is engaged between adjacent ribs. The inner support cylinder 3 effectively prevents the inner coil 201 from deforming or displacing due to fluid impact or vibration, enhances the mechanical stability and long-term operational reliability of the entire coil assembly 2, and provides a positioning reference for the manufacturing and assembly of the inner coil 201, simplifying the assembly process and improving production efficiency.

[0054] In one embodiment, the central axis of the supporting inner cylinder 3, the helical axis of the inner coil 201, and the helical axis of the outer coil 202 coincide, making the flow state of the working fluid more stable and uniform when it flows through the annular flow channel formed by the supporting inner cylinder 3, the inner coil 201, and the outer coil 202.

[0055] In this embodiment, the inner supporting cylinder 3 and the mounting shell 1 are kept coaxial by positioning brackets at both ends. The positioning brackets can be radial supporting ribs or annular supporting plates. The outer coil 202 can be centered by positioning grooves or positioning blocks on the inner wall of the mounting shell 1. The coaxial installation of the inner supporting cylinder 3, the inner coil 201, and the outer coil 202 can avoid the generation of flow deviation or local eddies, which is conducive to achieving uniform heat exchange and reducing flow resistance, thereby further improving heat exchange efficiency.

[0056] In this embodiment, the end of the inner support cylinder 3 facing the fluid outlet 105 is sealed. Specifically, the end face of the inner support cylinder 3 facing the fluid outlet 105 is sealed by welding or threaded sealing using an end plate or end cap to prevent water from entering the hollow area inside the inner support cylinder 3.

[0057] Furthermore, the closed end of the inner support cylinder 3 can be configured as a detachable structure, such as a flange cover, to facilitate the inspection and maintenance of the inner coil 201; or the end of the inner support cylinder 3 facing the fluid inlet 104 can be closed simultaneously, making the inner support cylinder 3 a completely sealed cylinder structure. When the working fluid enters the mounting housing 1 from the fluid inlet 104, during its flow to the fluid outlet 105, the closed end of the inner support cylinder 3 forces all the fluid to flow through the annular heat exchange space formed by the inner coil 201 and the outer coil 202 outside the inner support cylinder 3, and it cannot be directly discharged from the fluid outlet 105 through the inner support cylinder 3. This ensures that all fluids can fully exchange heat with the coil assembly 2, improving the utilization rate of the heat exchange medium and the effective heat exchange efficiency of the entire device, while avoiding insufficient heat exchange caused by fluid short circuits, ensuring the stable and reliable thermal performance of the heat exchange device.

[0058] In this embodiment, the mounting housing 1 is composed of three sealed parts: an upper cover 101, an outer cylinder 102, and a base 103. The upper cover 101 and the base 103 are welded to both ends of the outer cylinder 102, forming a sealed heat exchange chamber. The outer cylinder 102 is a cylindrical stainless steel cylinder or a titanium alloy cylinder. The upper cover 101 is a circular flat head or an elliptical head. A refrigerant connection hole for penetrating the first outlet 2012 and the second outlet 2022 is opened in the central area of ​​the upper cover 101. A water pipe interface for connecting to the water outlet is opened on the side of the upper cover 101. A refrigerant connection hole for penetrating the first inlet 2011 and the second inlet 2021 is opened in the central area of ​​the base 103. A water pipe interface for connecting to the fluid inlet 104 is opened on the side wall of the base 103. Threaded or flanged connecting short pipes are welded to both the refrigerant connection hole and the water pipe interface for easy sealing connection with external pipelines.

[0059] The counter-current heat exchanger provided in this embodiment divides the heat exchange titanium tubes into two parts: an inner coil 201 and an outer coil 202. The flow channel connection method is rationally designed to ensure that the refrigerant and water flow form a counter-current heat exchange overall, thereby maximizing the heat exchange temperature difference. Simultaneously, the finely designed small-diameter inner coil enhances fluid turbulence, effectively eliminates the central dead zone, and improves overall heat exchange performance. The inner coil 201 is located in the central region of the heat exchanger, with a coil diameter approximately 30%-40% of the inner diameter of the outer shell. The smaller tube spacing aims to enhance the turbulence of the fluid in this region. The outer coil 202 is arranged in the region of the outer shell near the inner wall, with a coil diameter approximately 70%-80% of the inner diameter of the outer shell. The tube spacing can be the same as or slightly larger than that of the inner coil. The ratio of the total length of the inner coil 201 to the total length of the outer coil 202 is controlled between 0.8 and 1.0 to ensure optimized flow distribution while maintaining a constant total tube usage.

[0060] In the parallel counter-current scheme, the first inlet 2011 and the second inlet 2021, which serve as refrigerant inlets, are connected by a Y-shaped tee or similar diverter to simultaneously distribute the refrigerant to the upper port of the inner coil 201 and the upper port of the outer coil 202. The refrigerant flows from top to bottom inside the pipes, while the cooling water / water flow flows from bottom to top outside the pipes, thus forming a complete counter-current heat exchange in both the inner and outer coils. In the series counter-current scheme, the refrigerant first enters the upper port of the outer coil 202, flows through the outer coil, and then is led from its lower port to the upper port of the inner coil 201 via a connecting pipe, finally flowing out from the lower port of the inner coil 201. The water flow remains from bottom to top, thus forming a counter-current flow throughout the heat exchanger.

[0061] According to an embodiment of this utility model, another aspect provides a swimming pool heat pump system, including a compressor, a counter-current heat exchanger provided in this application, an electronic expansion valve as a throttling element, an evaporator, and a water circulation assembly. The counter-current heat exchanger adopts the inner and outer coil 202 structure described in the foregoing embodiments of this application, which includes an inner coil 201 and an outer coil 202, and serves as a condenser in the swimming pool heat pump system. The high-pressure exhaust port of the compressor is connected to the first inlet 2011 and the second inlet 2021 of the counter-current heat exchanger through a refrigerant pipeline. The first outlet 2012 and the second outlet 2022 of the counter-current heat exchanger are connected to the inlet of the throttling element through a refrigerant pipeline. The outlet of the throttling element is connected to the inlet of the evaporator through a refrigerant pipeline. The outlet of the evaporator is connected to the low-pressure suction port of the compressor through a refrigerant pipeline, thereby forming a complete refrigerant circulation loop. The water circulation assembly includes a circulating water pump, a filter, and connecting pipes. The inlet of the circulating water pump is connected to the pool water via a water pipe, and the outlet of the circulating water pump is connected to the fluid inlet 104 of the counter-current heat exchanger via a water pipe. The fluid outlet 105 of the counter-current heat exchanger is connected to the inlet of the filter via a water pipe, and the outlet of the filter delivers the heated water back to the pool via a water pipe.

[0062] In this embodiment, the pool heat pump system operates by compressing low-temperature, low-pressure refrigerant gas into high-temperature, high-pressure gas in the compressor. This high-temperature, high-pressure gas simultaneously enters the inner coil 201 and outer coil 202 of the counter-current heat exchanger. In the counter-current heat exchanger, the high-temperature, high-pressure refrigerant gas flows downwards and exchanges heat counter-currently with water flowing upwards. The refrigerant releases heat and condenses into a high-pressure liquid, while the water absorbs heat and heats up. The condensed high-pressure liquid refrigerant flows out from the first outlet 2012 and the second outlet 2022, and after being depressurized by a throttling element, it enters the evaporator. In the evaporator, it absorbs external heat and evaporates into low-temperature, low-pressure gas, which is then drawn into the compressor for the next cycle. Simultaneously, the circulating water pump extracts low-temperature water from the pool and delivers it to the fluid inlet 104 of the counter-current heat exchanger. The water flows upwards in the heat exchange chamber, absorbing the condensation heat of the refrigerant and increasing in temperature. It then flows out from the fluid outlet 105, is purified by a filter, and returns to the pool, completing the water heating cycle. Because the counter-current heat exchanger uses an inner and outer coil 202 structure, it provides a larger heat exchange area without increasing the height of the mounting shell 1, enabling the pool heat pump system to achieve efficient heating in a compact installation space.

[0063] The swimming pool heat pump system in this embodiment significantly improves the heat exchange efficiency between refrigerant and water by using the full counter-current heat exchange device of this application as the condenser. Tests show that under nominal operating conditions, the heating capacity can be increased by 5% to 6%, and the system's coefficient of performance (COP) is improved from 3.85 in the traditional scheme to approximately 4.08. Simultaneously, the counter-current heat exchange design avoids refrigerant accumulation at the bottom of the condenser, ensuring full utilization of the effective heat exchange area. The inner and outer coil 202 structure eliminates the central heat exchange dead zone of traditional single-coil coils, resulting in a more uniform water flow distribution and further improving heat exchange performance. The filter installed in the water circulation assembly effectively filters impurities in the pool water, preventing impurities from depositing in the heat exchange chamber and affecting heat exchange efficiency, thus extending the service life of the full counter-current heat exchange device.

[0064] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A fully countercurrent heat exchanger, characterized in that, include: The mounting housing (1) has a heat exchange chamber inside. The mounting housing (1) has a fluid inlet (104) and a fluid outlet (105). The fluid inlet (104) and the fluid outlet (105) are respectively located at both ends of the mounting housing (1) along the length direction. A coil assembly (2) is installed inside the mounting housing (1). The coil assembly (2) includes an inner coil (201) and an outer coil (202). The inner coil (201) is arranged around the axis of the mounting housing (1), and the outer coil (202) is arranged around the inner coil (201). The inner coil (201) is provided with a first inlet (2011) and a first outlet (2012). The outer coil (202) is provided with a second inlet (2021) and a second outlet (2022). The first outlet (2012) and the second outlet (2022) penetrate one end of the mounting housing (1) where the fluid inlet (104) is provided. The first inlet (2011) and the second inlet (2021) penetrate one end of the mounting housing (1) where the fluid outlet (105) is provided.

2. The countercurrent heat exchanger according to claim 1, characterized in that, The first outlet (2012) and the second inlet (2021) are connected in series via a matching flow channel, or the second outlet (2022) and the first inlet (2011) are connected in series via a matching flow channel.

3. The countercurrent heat exchanger according to claim 1, characterized in that, The first inlet (2011) and the second inlet (2021) are connected in parallel to the external refrigerant supply equipment.

4. The all-countercurrent heat exchanger according to any one of claims 1 to 3, characterized in that, The inner coil (201) has a winding diameter of 30% to 40% of the inner diameter of the mounting housing (1), and the outer coil (202) has a winding diameter of 70% to 80% of the inner diameter of the mounting housing (1).

5. The all-countercurrent heat exchanger according to any one of claims 1 to 3, characterized in that, The inner coil (201) has a winding spacing of 2mm-4mm, and the outer coil (202) has a winding spacing of not less than that of the inner coil (201).

6. The all-countercurrent heat exchanger according to any one of claims 1 to 3, characterized in that, The ratio of the total length of the inner coil (201) to the total length of the outer coil (202) is 0.8 to 1.

0.

7. The all-countercurrent heat exchanger according to any one of claims 1 to 3, characterized in that, It also includes a supporting inner cylinder (3), which is installed inside the mounting housing (1), and the inner ring coil (201) is wound around and fixed on the outer side wall of the supporting inner cylinder (3).

8. The countercurrent heat exchanger according to claim 7, characterized in that, The inner support cylinder (3), the inner coil (201), and the outer coil (202) are coaxially installed.

9. The countercurrent heat exchanger according to claim 7, characterized in that, The supporting inner cylinder (3) is closed at one end facing the fluid outlet (105).

10. A swimming pool heat pump system, characterized in that, Includes the full countercurrent heat exchanger as described in any one of claims 1 to 9.

Images