Titanium tube heat exchanger and heat pump system having the same

Abstract

The utility model relates to the technical field of swimming pool heat pump, disclose a titanium tube heat exchanger and have its heat pump system. Titanium tube heat exchanger, include: pressure bearing casing, install fluid delivery pipe in the inner chamber of pressure bearing casing, fluid delivery pipe extends along the circumference of pressure bearing casing, interval sleeve, install in pressure bearing casing, interval sleeve cover and install in fluid delivery pipe outside, heat exchange coil, spiral around and install in first heat exchange space and second heat exchange space. Through interval sleeve and fluid delivery pipe in pressure bearing casing formed double -layer sleeve structure, the single chamber of traditional large diameter casing is divided into first heat exchange space and second heat exchange space of series communication, prolongs the flow path of heat exchange fluid inside pressure bearing casing, and forces heat exchange fluid to complete the return flow along the preset path, avoids the heat exchange performance loss caused by uneven fluid distribution, short circuit and dead zone when heat exchange fluid flows in large diameter casing, improves the uniformity of shell flow field, thereby improves the heat exchange efficiency.

Description

Technical Field

[0001] This utility model relates to the field of swimming pool heat pump technology, specifically to a titanium tube heat exchanger and a heat pump system having the same. Background Technology

[0002] Heat pump water heaters, swimming pool thermostats, and other heat exchange equipment widely employ shell-and-tube heat exchangers to achieve heat transfer. Among these, titanium tube heat exchangers are the preferred choice for these applications due to their excellent corrosion resistance, particularly their superior performance in harsh water conditions such as seawater and high chloride ion content. In titanium tube heat exchangers, the heat exchange fluid typically flows in the shell side, exchanging heat with the refrigerant in the tube side.

[0003] With the increasing size of equipment and ever-improving energy efficiency requirements, especially in large-diameter titanium tube heat exchangers with an inner diameter greater than 140mm, a large number of heat exchange tubes are typically arranged within the shell to meet the demand for high heat exchange capacity. In this case, using conventional multi-inlet / multi-outlet or other simple water circuit connections can easily lead to uneven water flow distribution within the wide shell-side space, resulting in flow short-circuiting, eddies, and even localized stagnation – "heat exchange dead zones." This chaotic water flow cannot form an ideal counter-current heat exchange mode, leading to a reduction in the average heat exchange temperature difference and thus limiting further improvements in overall heat exchange efficiency. Simultaneously, uneven water flow distribution can prevent some heat exchange tubes from fully utilizing their capacity and may exacerbate scaling and localized corrosion risks due to excessively low flow velocities, affecting the long-term stability and lifespan of the equipment. Utility Model Content

[0004] This invention provides a titanium tube heat exchanger and a heat pump system thereof, to solve the problem of reduced heat exchange efficiency in existing titanium tube heat exchangers when the inner diameter of the shell is increased.

[0005] In a first aspect, this utility model provides a titanium tube heat exchanger, comprising: A pressure-bearing housing has a first end and a second end that are axially opposite each other along the axial direction. A fluid delivery pipe is installed in the inner cavity of the pressure-bearing housing. The fluid delivery pipe extends circumferentially along the pressure-bearing housing. One end of the fluid delivery pipe extends from the first end to the outside of the pressure-bearing housing, and a first flow space is reserved between the other end and the inner wall of the second end of the pressure-bearing housing. The second end is provided with a fluid delivery port. A spacer sleeve is installed inside the pressure-bearing housing and is fitted around the fluid delivery pipe. One end of the spacer sleeve is fixedly connected to the second end of the pressure-bearing housing, and a second flow space is reserved between the other end and the inner wall of the first end of the pressure-bearing housing. The spacer sleeve and the fluid delivery pipe enclose a first heat exchange space, and the inner wall of the pressure-bearing housing and the spacer sleeve enclose a second heat exchange space. A heat exchange coil is spirally wound and installed in the first heat exchange space and the second heat exchange space. The input end and the output end of the heat exchange coil both extend through the second end of the pressure-bearing shell to the outside of the pressure-bearing shell.

[0006] When the titanium tube heat exchanger is operating, the heat exchange fluid flows in from the fluid delivery pipe, passes through the first flow space, and enters the first heat exchange space formed by the spacer sleeve and the fluid delivery pipe. Subsequently, the heat exchange fluid flows axially through the first heat exchange space, then flows back through the second flow space, enters the second heat exchange space formed by the inner wall of the pressure-bearing shell and the spacer sleeve, and finally flows out from the fluid delivery port. Similarly, the heat exchange fluid can also flow in from the fluid delivery port and out from the fluid delivery pipe in the opposite direction. Simultaneously, the heat exchange medium flows in from the inlet end of the heat exchange coil, flows in the coil spirally wound within the first and second heat exchange spaces, and finally flows out from the outlet end. During this process, the heat exchange fluid and the heat exchange medium exchange heat along a generally counter-current flow path, increasing the average heat transfer temperature difference and enhancing the overall heat exchange efficiency. Titanium tube heat exchangers utilize a double-layer sleeve structure formed by a spacer sleeve and a fluid delivery pipe within a pressure-bearing shell. This divides the single chamber of a traditional large-diameter shell into a series-connected first and second heat exchange space, extending the flow path of the heat exchange fluid within the pressure-bearing shell and forcing the fluid to complete a reverse flow along a preset path to form a co-current flow. This avoids heat exchange performance losses caused by uneven fluid distribution, short circuits, and dead zones when the fluid flows in a large-diameter shell, improving the uniformity of the shell-side flow field and thus enhancing heat exchange efficiency.

[0007] In one optional embodiment, the pressure-bearing shell includes a pressure-bearing outer cylinder and mounting bases and mounting top covers disposed at both ends of the pressure-bearing outer cylinder, wherein the mounting bases, the mounting top covers, and the pressure-bearing outer cylinder enclose a pressure-bearing cavity.

[0008] The pressure-bearing shell is designed as a sealed assembly of a pressure-bearing outer cylinder, a mounting base, and a mounting top cover. This facilitates the step-by-step assembly and positioning of the internal components of the pressure-bearing shell, and allows for the installation and fixation of the fluid delivery pipe and spacer sleeve inside the pressure-bearing outer cylinder. Furthermore, the mounting base and mounting top cover, as independent end seals, allow for flexible design of interface forms based on the location requirements of the fluid inlet and outlet, enhancing the flexibility of the structural design and promoting standardized and modular production.

[0009] In one alternative embodiment, the fluid delivery pipe extends from the side of the mounting base to the outside of the pressure-bearing housing; and / or, the fluid delivery port is located on the side of the mounting top cover.

[0010] The fluid delivery pipe extends from the side of the mounting base to the outside of the pressure-bearing shell, serving as the inlet or outlet of the heat exchange fluid; the fluid delivery port is located on the side of the mounting top cover, serving as the other corresponding outlet or inlet of the heat exchange fluid. Positioning the fluid delivery pipe and fluid delivery port on the sides of the mounting base and mounting top cover respectively facilitates connection to external pipelines and system integration, and optimizes the internal space layout of the pressure-bearing shell.

[0011] In one optional embodiment, the heat exchange coil includes an outer coil and an inner coil, the outer coil being located in the second heat exchange space, the inner coil being located in the first heat exchange space, and the outer coil and the inner coil being connected in series via a connecting pipe.

[0012] The heat exchange coils are divided into outer and inner coils arranged in series. This allows the heat exchange medium to flow sequentially through the first and second heat exchange zones, creating counter-current heat exchange with the heat exchange fluid in different sections. This effectively increases the heat exchange area per unit space, achieving a larger total heat exchange area within the same pressure-bearing outer cylinder volume, thus improving heat exchange efficiency. Simultaneously, the series connection of the outer and inner coils extends the flow path of the heat exchange medium, increasing the heat exchange time. Combined with the reversible flow of the heat exchange fluid, this creates a fully counter-current heat exchange mode, maximizing the utilization of the heat transfer temperature difference and improving overall heat transfer performance. This is particularly suitable for the high-efficiency heat exchange requirements of large-diameter titanium tube heat exchangers.

[0013] In one optional embodiment, a flow clearance is provided between the pressure-bearing housing and the outer coil, and / or between the outer coil and the spacer sleeve, and / or between the spacer sleeve and the inner coil, and / or between the inner coil and the fluid delivery pipe.

[0014] By reserving flow gaps between components, heat exchange fluid is prevented from stagnating or short-circuiting in local areas. This ensures that the heat exchange fluid can evenly flush the entire outer surface of the outer and inner coils, enhancing the convective heat transfer coefficient between the heat exchange fluid and the heat exchange coils, and fully utilizing the efficiency of all heat exchange coils.

[0015] In one optional embodiment, the flow gap is 3mm-10mm. The heat exchange fluid can form a suitable flow velocity when flowing through each gap channel, avoiding both excessive flow resistance due to too small a gap and uneven heat exchange fluid distribution due to too large a gap. Furthermore, by setting a smaller flow gap, sufficiently strong turbulence can be induced in the heat exchange fluid, effectively disrupting the boundary layer near the pipe wall and improving the convective heat transfer coefficient.

[0016] In one optional embodiment, the input end of the heat exchange coil is connected to the outer coil, and the output end of the heat exchange coil is connected to the inner coil.

[0017] By coordinating the counter-current flow of the heat exchange fluid, both heat exchange sections maintain a counter-current state, significantly improving the average heat transfer temperature difference and overall heat exchange efficiency. Simultaneously, the heat exchange medium flows from the outside to the inside, facilitating the cascade utilization of heat and allowing the heat exchanger's thermodynamic performance to be fully realized.

[0018] In one alternative embodiment, the heat exchange fluid is adapted to be input from an opening at the first end of the fluid delivery pipe, and the heat exchange medium is adapted to be input from the input end of the heat exchange coil.

[0019] This allows the heat exchange fluid and the medium fluid to form a stable counter-current heat exchange mode in the two heat exchange spaces, maximizing the utilization of the heat transfer temperature difference. It also allows the heat exchange fluid to exchange heat with the heat exchange medium in different sections before and after the reversal, extending the effective heat exchange time and improving the utilization rate of the heat exchange area.

[0020] In one alternative embodiment, the pressure-bearing housing, the spacer sleeve, and the fluid delivery pipe are arranged coaxially.

[0021] This design creates a uniform annular flow channel between the first and second heat exchange spaces, ensuring the symmetry and uniformity of the heat exchange fluid distribution in the circumferential direction. The coaxial structure also eliminates flow asymmetry problems that may be caused by eccentric arrangement, allowing both the outer and inner coils to receive similar heat exchange fluid scouring intensity, improving the equal utilization rate of the heat exchange area, and thus ensuring the uniformity of the output heat exchange fluid temperature.

[0022] Secondly, this utility model also provides a heat pump system, including the titanium tube heat exchanger described in this utility model.

[0023] Since the heat pump system includes a titanium tube heat exchanger, it has the same effect as a titanium tube heat exchanger, so it will not be elaborated on here. Attached Figure Description

[0024] 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.

[0025] Figure 1 This is a longitudinal sectional view of a titanium tube heat exchanger provided in an embodiment of the present invention.

[0026] Figure 2 A perspective view of a titanium tube heat exchanger provided for an embodiment of this utility model.

[0027] Figure 3A cross-sectional view of a titanium tube heat exchanger provided in an embodiment of this utility model.

[0028] Explanation of reference numerals in the attached drawings: 1. Pressure-bearing shell; 101. Pressure-bearing outer cylinder; 102. Mounting base; 103. Mounting top cover; 2. Spacer sleeve; 3. Heat exchange coil; 301. Outer coil; 302. Inner coil; 303. Connecting pipe; 4. Fluid delivery pipe; 5. Fluid delivery port; 6. Flow gap. 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 3 The following describes embodiments of the present invention.

[0031] According to an embodiment of the present invention, a titanium tube heat exchanger is provided, comprising a pressure-bearing shell 1, a spacer sleeve 2, and a heat exchange coil 3.

[0032] The pressure-bearing shell 1 serves as the external support structure for the entire titanium tube heat exchanger. It has a first end and a second end arranged opposite each other along the axial direction, and a through-type cylindrical cavity is formed inside the pressure-bearing shell 1. Within the cavity of the pressure-bearing shell 1, fluid delivery pipes 4 are concentrically arranged, extending along the axial direction of the pressure-bearing shell 1. One end of the fluid delivery pipe 4 extends outward from the first end face of the pressure-bearing shell 1 to the outside of the pressure-bearing shell 1, serving to receive externally input heat exchange fluid. The other end of the fluid delivery pipe 4 extends to a position close to the second end face of the pressure-bearing shell 1, and this end of the fluid delivery pipe 4 maintains a certain axial distance from the inner wall of the second end of the pressure-bearing shell 1, thereby forming a first flow space between the fluid delivery pipe 4 and the second end of the pressure-bearing shell 1 for fluid passage. A fluid delivery port 5 is also provided at the second end face of the pressure-bearing shell 1, used to discharge the heat exchange fluid after heat exchange from inside the pressure-bearing shell 1.

[0033] A spacer sleeve 2 is installed inside the pressure-bearing housing 1. The spacer sleeve 2 has a cylindrical structure and is fitted over the fluid delivery pipe 4. The spacer sleeve 2, the fluid delivery pipe 4, and the pressure-bearing housing 1 are arranged concentrically. One end of the spacer sleeve 2 is fixedly connected to the inner wall of the end face of the second end of the pressure-bearing housing 1 to achieve a seal. The other end of the spacer sleeve 2 extends towards the first end of the pressure-bearing housing 1, and this end of the spacer sleeve 2 maintains a certain axial distance from the inner wall of the first end of the pressure-bearing housing 1, thereby forming a second flow space between the spacer sleeve 2 and the first end of the pressure-bearing housing 1 for fluid to pass through. With the above arrangement, the spacer sleeve 2 and the fluid delivery pipe 4 enclose an annular first heat exchange space, and the inner wall of the pressure-bearing housing 1 and the spacer sleeve 2 enclose an annular second heat exchange space. The first heat exchange space and the second heat exchange space are fluidly connected at the second end of the pressure-bearing housing 1 through the first flow space.

[0034] The heat exchange coil 3 is installed in the first and second heat exchange spaces in a spiral manner. Both the inlet and outlet ends of the heat exchange coil 3 penetrate the side wall of the pressure-bearing shell 1 from the second end face of the shell and extend to the outside of the shell 1, for connecting to external heat exchange medium pipelines. The heat exchange coil 3 forms a spiral winding structure in both the first and second heat exchange spaces to increase the contact area with the heat exchange fluid.

[0035] During the operation of the titanium tube heat exchanger, the heat exchange fluid first flows into the fluid delivery pipe 4 through the opening at the first end of the pressure-bearing shell 1. The fluid flows axially along the fluid delivery pipe 4 to the second end of the pressure-bearing shell 1, then flows out of the fluid delivery pipe 4 through the first flow space and enters the first heat exchange space formed by the spacer sleeve 2 and the fluid delivery pipe 4. After entering the first heat exchange space, the heat exchange fluid flows axially along the pressure-bearing shell 1 and exchanges heat with the heat exchange coils 3 within the first heat exchange space. When the heat exchange fluid reaches the first end of the pressure-bearing shell 1, its flow direction is reversed through the second flow space, and it enters the second heat exchange space formed by the inner wall of the pressure-bearing shell 1 and the spacer sleeve 2. In the second heat exchange space, the heat exchange fluid flows in the opposite direction to its previous flow direction in the fluid delivery pipe 4 and exchanges heat again with the heat exchange coils 3 within the second heat exchange space. Finally, it flows out of the pressure-bearing shell 1 from the fluid delivery port 5 located at the second end of the pressure-bearing shell 1. It should be noted that, depending on the actual application requirements, the flow direction of the heat exchange fluid can also be reversed. That is, the heat exchange fluid can flow into the titanium tube heat exchanger from the fluid delivery port 5, flow in the opposite direction of the above path, and finally flow out from the fluid delivery pipe 4.

[0036] Simultaneously, the heat exchange medium flows into the heat exchange coil 3 from the inlet end of the coil, and flows within the coil spirally arranged in the first and second heat exchange spaces. During this flow, it exchanges heat with the heat exchange fluids in the first and second heat exchange spaces through the coil wall. After completing the heat exchange, the heat exchange medium finally flows out of the titanium tube heat exchanger from the outlet end of the coil 3. In the above flow process, the heat exchange fluid and the heat exchange medium exchange heat along a generally counter-current flow path, thus forming a counter-current heat exchange mode, increasing the average heat transfer temperature difference, and enhancing the overall heat exchange efficiency. More importantly, the titanium tube heat exchanger, through the double-layer sleeve structure formed by the spacer sleeve 2 and the fluid delivery pipe 4 within the pressure-bearing shell 1, divides the single chamber of the traditional large-diameter shell into a first heat exchange space and a second heat exchange space connected in series. This extends the flow path of the heat exchange fluid inside the pressure-bearing shell 1 and forces the heat exchange fluid to complete a zigzag flow along a preset path, forming a long-path, unidirectional flow pattern. This effectively avoids the loss of heat exchange performance caused by uneven fluid distribution, short circuits, and dead zones when the heat exchange fluid flows in a large-diameter shell, improves the uniformity of the shell-side flow field, and thus improves the overall heat exchange efficiency of the titanium tube heat exchanger.

[0037] In one embodiment, the pressure-bearing housing 1 includes a pressure-bearing outer cylinder 101 and mounting bases 102 and mounting top covers 103 disposed at both ends of the pressure-bearing outer cylinder 101. The mounting bases 102, mounting top covers 103, and pressure-bearing outer cylinder 101 together form a sealed pressure-bearing cavity. The pressure-bearing outer cylinder 101 preferably adopts a cylindrical structure and is made of PVC material through extrusion molding or injection molding. Its inner diameter is typically between 140mm and 300mm, and the wall thickness is designed to be between 5mm and 15mm according to the pressure requirements. Both the mounting base 102 and the mounting top cover 103 are made of the same or similar PVC material as the pressure-bearing outer cylinder 101. The mounting base 102 is sealed to the first end of the pressure-bearing outer cylinder 101 by hot-melt welding or bonding. Similarly, the mounting top cover 103 is sealed to the second end of the pressure-bearing outer cylinder 101 by hot-melt welding or bonding. The three together form a pressure-bearing cavity, which can withstand the strong water pressure during the operation of the heat exchanger without being damaged, thereby ensuring the safety and reliability of the entire system.

[0038] As an alternative implementation, the pressure-bearing outer cylinder 101, the mounting base 102, and the mounting top cover 103 can also adopt an integrally formed structure, or achieve sealing through detachable methods such as flange connection or threaded connection. In situations where frequent maintenance is required, the detachable end cover structure has better maintenance convenience and can easily clean or replace the internal heat exchange coil 3.

[0039] Furthermore, the fluid delivery pipe 4 extends from the side of the mounting base 102 to the outside of the pressure-bearing shell 1, and the fluid delivery port 5 is located on the side of the mounting top cover 103. The fluid delivery pipe 4 extends radially or tangentially from the side of the mounting base 102 to the outside of the pressure-bearing shell 1, serving as the inlet channel for the heat exchange fluid to enter the titanium tube heat exchanger. The connection between the fluid delivery pipe 4 and the mounting base 102 is achieved through sealing welding or threaded sealing to ensure watertightness. The fluid delivery port 5 is located on the side of the mounting top cover 103, serving as the outlet channel for the heat exchange fluid to exit the titanium tube heat exchanger after heat exchange is completed. The fluid delivery port 5 is integrally formed with the mounting top cover 103 or connected by hot-melt welding.

[0040] The fluid delivery pipe 4 and the fluid delivery port 5 are respectively set on the side of the mounting base 102 and the mounting top cover 103, which facilitates the connection with the external piping system and the overall system integration of the heat pump unit. This optimizes the internal spatial layout of the pressure-bearing shell 1 and makes the pipe connection more compact and reasonable.

[0041] In one embodiment, the heat exchange coil 3 includes an outer coil 301 and an inner coil 302. The outer coil 301 is located in the second heat exchange space, and the inner coil 302 is located in the first heat exchange space. The outer coil 301 and the inner coil 302 are connected in series through a connecting pipe 303.

[0042] The outer coil 301 is spirally wound within the second heat exchange space formed by the inner wall of the pressure-bearing shell 1 and the spacer sleeve 2. The outer diameter of the outer coil 301 is slightly smaller than the inner diameter of the pressure-bearing shell 1, and the inner diameter is slightly larger than the outer diameter of the spacer sleeve 2. The pitch of the outer coil 301 is evenly distributed. The inner coil 302 is spirally wound within the first heat exchange space formed by the spacer sleeve 2 and the fluid transport pipe 4. The outer diameter of the inner coil 302 is slightly smaller than the inner diameter of the spacer sleeve 2, and the inner diameter is slightly larger than the outer diameter of the fluid transport pipe 4. The pitch of the inner coil 302 can be the same as or different from that of the outer coil 301.

[0043] The outer coil 301 and the inner coil 302 are connected in series inside the pressure-bearing shell 1 via a titanium elbow connecting pipe 303. Dividing the heat exchange coil 3 into an outer coil 301 and an inner coil 302 and arranging them in series allows the heat exchange medium to flow sequentially through the second and first heat exchange spaces, forming counter-current heat exchange with the heat exchange fluid in different sections. This effectively increases the heat exchange area per unit space, achieving a larger total heat exchange area within the same pressure-bearing outer cylinder 101 volume, thus improving heat exchange efficiency. Simultaneously, the series structure of the outer coil 301 and the inner coil 302 extends the flow path of the heat exchange medium, increasing the heat exchange time. Combined with the reversible flow of the heat exchange fluid, this forms a fully counter-current heat exchange mode, maximizing the utilization of the heat transfer temperature difference and improving overall heat transfer performance. This is particularly suitable for the high-efficiency heat exchange requirements of large-diameter titanium tube heat exchangers.

[0044] In one embodiment, a flow gap 6 is provided between the pressure-bearing housing 1 and the outer coil 301, between the outer coil 301 and the spacer sleeve 2, between the spacer sleeve 2 and the inner coil 302, and between the inner coil 302 and the fluid delivery pipe 4.

[0045] A flow gap 6 is reserved between each component to prevent the heat exchange fluid from stagnating or short-circuiting in local areas, ensuring that the heat exchange fluid can evenly flush the entire outer surface of the outer coil 301 and the inner coil 302, enhancing the convective heat transfer coefficient between the heat exchange fluid and the heat exchange coil 3, and fully utilizing the efficiency of all heat exchange coils 3.

[0046] Specifically, the flow gap 6 is 3mm-10mm. This allows the heat exchange fluid to achieve a suitable flow velocity as it flows through each gap channel, avoiding both excessive flow resistance due to too small a gap and uneven heat exchange fluid distribution due to too large a gap. By setting the flow gap 6 within this size range, sufficient turbulence can be induced in the heat exchange fluid, effectively disrupting the boundary layer near the pipe wall and improving the convective heat transfer coefficient. Simultaneously, the gap size of 3mm to 10mm ensures good heat transfer performance while keeping the flow resistance within a reasonable range.

[0047] In one embodiment, the inlet of heat exchange coil 3 is connected to the outer coil 301, and the outlet of heat exchange coil 3 is connected to the inner coil 302. Both the inlet and outlet of heat exchange coil 3 are equipped with titanium threaded connectors serving as refrigerant inlets and outlets for connection to other components of the heat pump system; their dimensions are determined based on the titanium tube dimensions. The heat exchange medium enters the outer coil 301 from the inlet of heat exchange coil 3 located on the second end side of the pressure-bearing housing 1, forming a counter-current heat exchange with the heat exchange fluid in the second heat exchange space. It then flows into the inner coil 302 through connecting pipe 303, continuing heat exchange with the heat exchange fluid in the first heat exchange space, and finally exits from the outlet of the inner coil 302. This flow path, combined with the reversible flow of the heat exchange fluid, ensures that the flow direction of the heat exchange medium and the heat exchange fluid in the second heat exchange space is opposite, forming a stable counter-current heat exchange state, significantly improving the average heat transfer temperature difference and overall heat exchange efficiency. Meanwhile, the heat exchange medium flows from the outside to the inside, which is conducive to the cascade utilization of heat. This allows the higher-temperature heat exchange medium to exchange heat with the higher-temperature heat exchange fluid in the second heat exchange space, and the slightly lower-temperature heat exchange medium to exchange heat with the slightly lower-temperature heat exchange fluid in the first heat exchange space, so that the thermodynamic performance of the heat exchanger can be fully utilized.

[0048] Accordingly, the heat exchange fluid enters through the opening at the first end of the fluid delivery pipe 4, while the heat exchange medium enters through the input end of the heat exchange coil 3. During normal operation of the titanium tube heat exchanger, the heat exchange fluid, as the shell-side fluid, enters through the opening at the bottom of the first end of the pressure-bearing shell 1 of the fluid delivery pipe 4, flows axially along the fluid delivery pipe 4 to the second end, and then turns back into the second heat exchange space. Simultaneously, the heat exchange medium, as the tube-side fluid, enters through the input end of the heat exchange coil 3, flowing sequentially through the outer coil 301 and the inner coil 302. This allows the heat exchange fluid and heat exchange medium to form a stable counter-current heat exchange mode in the two heat exchange spaces, with the flow directions of the two fluids being completely opposite, maximizing the utilization of the heat transfer temperature difference. The heat exchange fluid exchanges heat with the heat exchange medium in different sections before and after the turnback, extending the effective heat exchange time.

[0049] The input positions of the heat exchange fluid and the heat exchange medium can also be interchanged. That is, the heat exchange fluid is input from the fluid delivery port 5 and output from the fluid delivery pipe 4, and the heat exchange medium is input from the inner coil 302 and output from the outer coil 301. This interchangeable flow direction design can also achieve full countercurrent heat exchange. In engineering applications, it can be flexibly selected according to the convenience of pipeline connection.

[0050] In this embodiment, the pressure-bearing shell 1, the spacer sleeve 2, and the fluid delivery pipe 4 are arranged coaxially. During assembly, the fluid delivery pipe 4 is first positioned at the center of the mounting base 102, then the spacer sleeve 2 is fitted over the fluid delivery pipe 4, and the concentricity of the spacer sleeve 2 and the fluid delivery pipe 4 is ensured by a positioning ring or a centering bracket. Finally, the pressure-bearing outer cylinder 101 is fitted over the spacer sleeve 2, and the coaxiality deviation of the three components is ensured by an overall tooling.

[0051] The coaxial arrangement creates a uniform annular flow channel between the first and second heat exchange spaces, ensuring the symmetry and uniformity of the heat exchange fluid distribution in the circumferential direction and reducing circumferential velocity deviation. The coaxial structure also eliminates flow asymmetry problems that may result from eccentric arrangement, allowing both the outer coil 301 and the inner coil 302 to receive similar heat exchange fluid scouring intensity, improving the equal utilization rate of the heat exchange area, and thus ensuring the uniformity of the output heat exchange fluid temperature.

[0052] It should be noted that in specific application scenarios, such as when heat exchange on a certain side needs to be enhanced, the pressure shell 1, the spacer sleeve 2 and the fluid delivery pipe 4 can also be arranged eccentrically. A specific heat exchange fluid distribution can be achieved through the asymmetrical flow channel design. Although this eccentric design will reduce the overall uniformity, it has certain advantages in local heat exchange enhancement. Those skilled in the art can flexibly choose the concentric or eccentric arrangement scheme according to the specific heat exchange requirements.

[0053] According to an embodiment of the present invention, another aspect provides a heat pump system, including a compressor, an expansion valve, an evaporator, and the titanium tube heat exchanger of the present invention.

[0054] The inlet of heat exchange coil 3 of the titanium tube heat exchanger is connected to the compressor's exhaust port via a pipeline, and the outlet of heat exchange coil 3 is connected to the expansion valve's inlet via a pipeline. The fluid delivery pipe 4 of the titanium tube heat exchanger is connected to an external hot water circulation loop via a pipeline, and the fluid delivery port 5 of the titanium tube heat exchanger is connected to an external cold water return pipe via a pipeline. During heat pump system operation, low-temperature, low-pressure refrigerant gas is compressed into high-temperature, high-pressure gas in the compressor. This high-temperature, high-pressure refrigerant gas exits from the compressor's exhaust port and enters heat exchange coil 3 of the titanium tube heat exchanger. It flows within heat exchange coil 3 and exchanges heat with water in the first and second heat exchange spaces of the titanium tube heat exchanger. After releasing heat, the refrigerant gas condenses into a high-pressure liquid. This high-pressure liquid refrigerant flows out from the outlet of heat exchange coil 3 and enters the expansion valve for throttling and pressure reduction. The throttled, low-temperature, low-pressure refrigerant then enters the evaporator to absorb heat from an external heat source and evaporates into gas, before re-entering the compressor to complete the cycle. In this process, external cold water enters through the fluid delivery pipe 4 of the titanium tube heat exchanger, and is heated into hot water after countercurrent heat exchange with the high-temperature refrigerant inside the titanium tube heat exchanger. The hot water is then output to the external hot water circulation system from the fluid delivery port 5 of the titanium tube heat exchanger. Because the heat pump system uses the titanium tube heat exchanger of this invention as the condenser, it achieves the same technical effects as the titanium tube heat exchanger in improving heat exchange efficiency, improving water flow distribution, and reducing manufacturing costs. The overall energy efficiency ratio of the heat pump system can be improved by more than 10%, and the hot water output temperature is more stable and uniform.

[0055] 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 titanium tube heat exchanger, characterized in that, include: A pressure-bearing housing (1) has a first end and a second end that are axially opposite each other along the axial direction. A fluid delivery pipe (4) is installed in the inner cavity of the pressure-bearing housing (1). The fluid delivery pipe (4) extends circumferentially along the pressure-bearing housing (1). One end of the fluid delivery pipe (4) extends from the first end to the outside of the pressure-bearing housing (1), and a first flow space is reserved between the other end and the inner wall of the second end of the pressure-bearing housing (1). A fluid delivery port (5) is provided at the second end. A spacer sleeve (2) is installed inside the pressure-bearing housing (1). The spacer sleeve (2) is sleeved on the outside of the fluid conveying pipe (4). One end of the spacer sleeve (2) is fixedly connected to the second end of the pressure-bearing housing (1), and the other end is reserved between the spacer sleeve (2) and the inner wall of the first end of the pressure-bearing housing (1) to form a second flow space. The spacer sleeve (2) and the fluid conveying pipe (4) enclose a first heat exchange space, and the inner wall of the pressure-bearing housing (1) and the spacer sleeve (2) enclose a second heat exchange space. The heat exchange coil (3) is spirally wound and installed in the first heat exchange space and the second heat exchange space. The input end and the output end of the heat exchange coil (3) both extend through the second end of the pressure shell (1) to the outside of the pressure shell (1).

2. The titanium tube heat exchanger according to claim 1, characterized in that, The pressure-bearing shell (1) includes a pressure-bearing outer cylinder (101) and mounting bases (102) and mounting top covers (103) located at both ends of the pressure-bearing outer cylinder (101). The mounting bases (102), the mounting top covers (103), and the pressure-bearing outer cylinder (101) enclose a pressure-bearing cavity.

3. The titanium tube heat exchanger according to claim 2, characterized in that, The fluid delivery pipe (4) extends from the side of the mounting base (102) to the outside of the pressure-bearing housing (1); and / or, the fluid delivery port (5) is located on the side of the mounting top cover (103).

4. The titanium tube heat exchanger according to any one of claims 1 to 3, characterized in that, The heat exchange coil (3) includes an outer coil (301) and an inner coil (302). The outer coil (301) is located in the second heat exchange space, and the inner coil (302) is located in the first heat exchange space. The outer coil (301) and the inner coil (302) are connected in series through a connecting pipe (303).

5. The titanium tube heat exchanger according to claim 4, characterized in that, An overflow gap (6) is provided between the pressure-bearing shell (1) and the outer coil (301) and / or between the outer coil (301) and the spacer sleeve (2) and / or between the spacer sleeve (2) and the inner coil (302) and / or between the inner coil (302) and the fluid delivery pipe (4).

6. The titanium tube heat exchanger according to claim 5, characterized in that, The flow gap (6) is 3mm-10mm.

7. The titanium tube heat exchanger according to claim 4, characterized in that, The input end of the heat exchange coil (3) is connected to the outer coil (301), and the output end of the heat exchange coil (3) is connected to the inner coil (302).

8. The titanium tube heat exchanger according to any one of claims 1 to 3, characterized in that, The heat exchange fluid is adapted to be input from the opening at the first end of the fluid delivery pipe (4), and the heat exchange medium is adapted to be input from the input end of the heat exchange coil (3).

9. The titanium tube heat exchanger according to any one of claims 1 to 3, characterized in that, The pressure-bearing shell (1), the spacer sleeve (2), and the fluid delivery pipe (4) are arranged coaxially.

10. A heat pump system, characterized in that, Includes the titanium tube heat exchanger as described in any one of claims 1 to 9.

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