CN114812228B - Heat exchangers and heat pump systems - Google Patents

Abstract

The present application provides a heat exchanger and a heat pump system. The heat exchanger has an evaporator working mode and a condenser working mode, wherein the heat exchanger includes a shell, a heat exchange tube bundle, a first inlet pipe, a second inlet pipe, a first outlet pipe, a second outlet pipe and a fluid guiding structure. The shell has a cavity. The heat exchange tube bundle is accommodated in the cavity. The first inlet pipe, the second inlet pipe, the first outlet pipe and the second outlet pipe are connected to the shell and are in fluid communication with the cavity. The fluid guiding structure is arranged in the cavity and is configured to respectively define different flow paths of the heat exchanger in the condenser working mode and in the evaporator working mode. The heat exchanger of the present application can ensure a high heat exchange efficiency, and can also ensure that the fluid flowing out of the first outlet pipe is free of liquid, and is conducive to the discharge of the lubricant. The heat pump system of the present application does not need to be provided with a refrigerant liquid reservoir, which greatly simplifies the components and connection relationships of the heat pump system.

Description

Heat exchanger and heat pump system

Technical Field

The application relates to the field of heat exchangers, in particular to a heat exchanger in a heat pump system.

Background

In the prior art, the falling film evaporator is an evaporator with higher heat exchange efficiency. However, conventional falling film evaporators cannot be used as condensers. In a reversible heat pump system, the heat exchanger has a need to function as both an evaporator and a condenser.

Thus, there is a need for a heat exchanger that can be used as either a falling film evaporator or a condenser.

Disclosure of Invention

In order to achieve the above object, the present application provides a heat exchanger having an evaporator operation mode and a condenser operation mode, wherein the heat exchanger comprises a housing, a heat exchange tube bundle, a first inlet tube, a second inlet tube, a first outlet tube, a second outlet tube, and a fluid guiding structure. The housing has a cavity. The heat exchange tube bundle is accommodated in the accommodating chamber. The first inlet tube, the second inlet tube, the first outlet tube, and the second outlet tube are connected to the housing and in fluid communication with the plenum, wherein the first inlet tube, the second inlet tube, and the first outlet tube are positioned above the heat exchange tube bundle, and the second outlet tube is positioned below the heat exchange tube bundle. The fluid directing structure is disposed in the cavity and is configured to define different flow paths of the heat exchanger in the condenser operating mode and in the evaporator operating mode, respectively. When the heat exchanger is in the evaporator operation mode, the fluid guiding structure guides the fluid flowing in from the first inlet pipe to exchange heat with the fluid in the heat exchange tube bundle so as to evaporate the fluid into gas, and guides the gas formed by evaporation to be discharged out of the heat exchanger through the first outlet pipe. When the heat exchanger is in the condenser operating mode, the fluid directing structure directs fluid flowing in from the second inlet tube into heat exchange relationship with fluid in the heat exchange tube bundle to condense it into liquid, and liquid formed by the subsequent condensation exits the heat exchanger via the second outlet tube.

According to the heat exchanger described above, the fluid guiding structure comprises a main baffle assembly arranged in the cavity and dividing the cavity into a first cavity located at the upper part and a second cavity located at the lower part, wherein the heat exchange tube bundle is arranged in the second cavity, the first outlet tube is communicated with the first cavity, and the second outlet tube is communicated with the second cavity. The main baffle plate assembly is provided with a first communication port and a second communication port, and the first inlet pipe and the second inlet pipe are respectively communicated with the second containing cavity through the first communication port and the second communication port. Wherein the fluid guiding structure guides the fluid flowing in from the first inlet pipe to enter the second accommodating chamber through the first communication port when the heat exchanger is in the evaporator operation mode, and guides the fluid flowing in from the second inlet pipe to enter the second accommodating chamber through the second communication port when the heat exchanger is in the condenser operation mode. The main baffle assembly is provided with a plurality of channels, and the first containing cavity and the second containing cavity can be in fluid communication through the channels.

According to the heat exchanger described above, the fluid guiding structure further comprises a distributor arranged between the first inlet pipe and the heat exchange tube bundle. The dispenser comprises a dispenser housing, a dispenser cavity defined by the dispenser housing, and a dispenser inlet and a plurality of dispenser outlets which are formed in the dispenser housing and are communicated with the dispenser cavity. The distributor is configured such that fluid flowing in from the first inlet tube enters the distributor plenum via the distributor inlet and is distributed from the plurality of distributor outlets to the heat exchange tube bundle.

According to the heat exchanger, the distributor is arranged below the main baffle assembly, and the first inlet pipe is communicated with the distributor inlet through the first communication port on the main baffle assembly, so that fluid flowing in the first inlet pipe can sequentially flow through the first communication port, the distributor inlet, the distributor accommodating cavity and the distributor outlet and then enter the second accommodating cavity.

According to the heat exchanger described above, the fluid guiding structure further includes a buffer disposed in the second chamber and disposed between the main baffle assembly and the heat exchange tube bundle, the buffer being disposed below the second communication port with a first distance from the second communication port, the first distance enabling fluid from the second communication port to enter the second chamber.

According to the heat exchanger, a plurality of distributor outlets of the distributor are positioned below the buffer.

According to the heat exchanger described above, the buffer is a buffer plate having a buffer length extending in a length direction of the housing and having a buffer width extending along a width of the housing. The buffer plates are connected to the main baffle plate assembly at two ends of the shell in the width direction, so that fluid entering the second containing cavity from the second communication port flows to the heat exchange tube bundle after flowing along the length direction of the shell.

According to the above heat exchanger, the buffer length and the buffer width of the buffer plate are configured to be able to cover the second communication port.

According to the heat exchanger, the heat exchange tube bundle comprises a first group of heat exchange tubes and a second group of heat exchange tubes, and the first group of heat exchange tubes are positioned above the second group of heat exchange tubes. Wherein the first set of heat exchange tubes comprises a first number of heat exchange tubes and the second set of heat exchange tubes comprises a second number of heat exchange tubes. Wherein the ratio of the first number to the second number is greater than 2:1.

According to the heat exchanger, the bottom of the first group of heat exchange tubes is a second distance from the top of the second group of heat exchange tubes. The housing is circular in cross section and has an inner diameter. Wherein the ratio of the second distance to the inner diameter is less than 1:2.

The application also provides a heat pump system, which comprises the heat exchanger. The heat pump system is provided with a refrigerating working mode and a heating working mode, when the heat pump system is in the refrigerating working mode, the heat exchanger is used as an evaporator, and when the heat pump system is in the heating working mode, the heat exchanger is used as a condenser.

The heat exchanger of the application has two working modes, namely an evaporator working mode and a condenser working mode. When the heat exchanger is in the working mode of the evaporator, the heat exchanger has at least the following advantages that firstly, the heat exchanger can realize falling film evaporation heat exchange, and higher heat exchange efficiency can be ensured. Second, the heat exchanger of the present application can ensure that the fluid flowing out of the first outlet pipe is free of liquid. Third, the heat exchanger of the present application facilitates the discharge of lubricant. The heat exchanger of the application can store the fluid condensed into liquid in the condenser working mode, thereby avoiding the arrangement of an external storage.

The heat pump system of the application does not need to be provided with a refrigerant liquid storage device, thereby greatly simplifying the components and connection relation of the heat pump system.

Other features, advantages, and embodiments of the application may be set forth or apparent from consideration of the following detailed description, drawings, and claims. Furthermore, it is to be understood that both the foregoing summary and the following detailed description are exemplary and intended to provide further explanation without limiting the scope of the application as claimed. However, the detailed description and the specific examples merely indicate preferred embodiments of the application. Various changes and modifications within the spirit and scope of the application will become apparent to those skilled in the art from this detailed description.

Drawings

The features and advantages of the present application may be better understood by reading the following detailed description taken in conjunction with the drawings in which like reference designators refer to like elements throughout, and in which:

FIG. 1 is a perspective view of a heat exchanger of the present application;

FIG. 2 is an axial cross-sectional view of the heat exchanger shown in FIG. 1;

FIG. 3 is a cross-sectional view of the heat exchanger shown in FIG. 1 taken along line A-A of FIG. 2;

FIG. 4 is a cross-sectional view of the heat exchanger shown in FIG. 1 taken along line B-B of FIG. 2;

FIG. 5A is an axial cross-sectional view of the heat exchanger of FIG. 1, illustrating a path of movement of fluid across the axial cross-sectional view of the heat exchanger when the heat exchanger is in an evaporator mode of operation;

FIG. 5B is a cross-sectional view of the heat exchanger of FIG. 1 taken along line A-A of FIG. 2, illustrating the path of movement of fluid on an axial cross-sectional view of the heat exchanger when the heat exchanger is in an evaporator mode of operation;

FIG. 6A is an axial cross-sectional view of the heat exchanger of FIG. 1, illustrating the path of movement of fluid across the axial cross-sectional view of the heat exchanger when the heat exchanger is in a condenser mode of operation;

FIG. 6B is a cross-sectional view of the heat exchanger of FIG. 1 taken along line B-B of FIG. 2, illustrating the path of movement of fluid on an axial cross-sectional view of the heat exchanger when the heat exchanger is in a condenser mode of operation;

FIG. 7 is a system diagram of a heat pump system employing the heat exchanger of the present application;

FIG. 8A is a system diagram of the heat pump system of FIG. 7 in a cooling mode;

Fig. 8B is a system diagram of the heat pump system shown in fig. 7 in a heating mode.

Detailed Description

Various embodiments of the present invention are described below with reference to the accompanying drawings, which form a part hereof. It is to be understood that, although directional terms, such as "front", "rear", "upper", "lower", "left", "right", etc., may be used in describing various exemplary structural portions and elements of the present invention, these terms are used herein for convenience of description only and are determined based on the exemplary orientations shown in the drawings. Since the disclosed embodiments of the invention may be arranged in a variety of orientations, these directional terms are used by way of illustration only and are in no way limiting. In the drawings below, like reference numerals refer to like elements, and like reference numerals refer to like elements.

Fig. 1 is a perspective view of a heat exchanger 100 according to the present application, fig. 2 is an axial sectional view of the heat exchanger 100 shown in fig. 1, fig. 3 is a sectional view of the heat exchanger 100 shown in fig. 1 taken along the line A-A in fig. 2, and fig. 4 is a sectional view of the heat exchanger 100 shown in fig. 1 taken along the line B-B in fig. 2 to show a specific structure of the heat exchanger 100.

As shown in fig. 1-4, the heat exchanger 100 includes a housing 102. The housing 102 includes a cylinder 131, a left partition plate 132, a right partition plate 133, a left end plate 135, and a right end plate 136. Wherein the cylinder 131 has an inner diameter D. The cylinder 131 extends in the longitudinal direction of the heat exchanger 100. The left and right ends of the cylinder 131 are closed by a left partition plate 132 and a right partition plate 133, respectively, to form a chamber 202. The left end plate 135 has a circular arc shape, and the left end plate 135 is connected to the left partition plate 132 to form a communication chamber 203. The right end plate 136 is also circular arc-shaped, and the right end plate 136 is connected to the right partition plate 133. The right divider plate 133 also includes a transverse divider plate 211 extending transversely from the right divider plate 133 to the right end plate 136, thereby forming an outlet plenum 212 and an inlet plenum 213.

As shown in fig. 1-2, the heat exchanger 100 further includes a first inlet pipe 112, a second inlet pipe 114, a first outlet pipe 124, a second outlet pipe 122, and a discharge pipe 125. First inlet tube 112, second inlet tube 114, first outlet tube 124, second outlet tube 122, and drain tube 125 are connected to housing 102 and are in fluid communication with volume 202. The first inlet pipe 112, the second inlet pipe 114, and the first outlet pipe 124 are located at substantially the upper portion of the cylinder 131. Wherein the first outlet tube 124, the first inlet tube 112, and the second inlet tube 114 are disposed along the length of the housing 102. The first outlet tube 124 is located at the left portion of the housing 102, the first inlet tube 112 is located at the middle portion of the housing 102, and the second inlet tube 114 is located at the right portion of the housing 102. The second outlet pipe 122 and the discharge pipe 125 are located substantially at the lower portion of the cylinder 131. Wherein the second outlet pipe 122 is located at the bottom of the housing 102, and the second outlet pipe 122 is located at the middle of the housing 102 in the length direction of the housing 102. The discharge pipe 125 is located at a lower portion of the housing 102, and in a length direction of the housing 102, the discharge pipe 125 is located at a left portion of the housing 102, which is disposed downward obliquely to a vertical direction in a radial direction of the housing 102.

The heat exchanger 100 of the present application has an evaporator mode of operation and a condenser mode of operation, and when the heat exchanger 100 is in either the evaporator mode of operation or the condenser mode of operation, the fluid will have different flow paths after entering the heat exchanger 100 from different inlets. As shown in fig. 1-2, the heat exchanger 100 also includes a fluid directing structure. A fluid directing structure is disposed in the cavity 202 to define different flow paths for the heat exchanger 100 in the evaporator mode of operation and in the condenser mode of operation. Specifically, the fluid directing structure includes a main baffle assembly 231. The main baffle assembly 231 extends along the length of the housing 102 and is transversely disposed in the chamber 202 to divide the chamber 202 into a first chamber 204 at an upper portion and a second chamber 206 at a lower portion. As shown in fig. 3-4, the main baffle assembly 231 is generally stepped with lower ends and higher middle ends in a radial cross-section of the housing 102. The lower portions of both ends of the main barrier assembly 231 are provided with a plurality of passages 241 such that the first and second chambers 204 and 206 located at the upper and lower portions can communicate through the plurality of passages 241. Specifically, channel 241 is dog-bone shaped. The channel 241 has four adjacent fold line segments and two adjacent fold line segments are substantially 90 ° so that the fluid can change direction of movement multiple times as it moves in the channel 241. A first communication port 281 and a second communication port 282 are provided at a middle upper portion of the main shutter assembly 231. The first communication port 281 is located substantially at the middle position in the longitudinal direction of the housing 102, and the second communication port 282 is disposed substantially near the right end. The first inlet pipe 112 communicates with the first communication port 281, and the outlet of the second inlet pipe 114 communicates with the second communication port 282.

As shown in fig. 2, the fluid guiding structure of the heat exchanger 100 further comprises a first inlet pipe expander 291. The first inlet tube expander 291 is disposed in the first chamber 204. Which is disposed over the first communication port 281 and is connected to the first inlet pipe 112 and the main baffle assembly 231. Specifically, the first inlet pipe expander 291 is a pipe having a larger pipe diameter than the first inlet pipe 112. The upper portion thereof is connected to the first inlet pipe 112, and the opening 292 of the upper portion thereof communicates with the outlet of the first inlet pipe 112. The lower portion thereof is covered on the main barrier assembly 231 and the opening 293 of the lower portion thereof is made to communicate with the first communication port 281. Thereby, the fluid flowing in from the first inlet pipe 112 can flow into the second chamber 206 through the first inlet pipe expander 291 and the first communication port 281. After exiting the first inlet tube 112, the fluid can reduce the flow velocity in the first inlet tube expander 291.

As shown in fig. 2-3, the fluid directing structure of the heat exchanger 100 further comprises a distributor 221. The dispenser 221 is disposed below the main shutter assembly 231. The dispenser 221 includes a dispenser housing 225 defining a dispenser receptacle 226. The dispenser housing 225 extends generally along the length of the housing 102. The upper portion of the dispenser housing 225 is provided with a dispenser inlet 222. Specifically, the dispenser inlet 222 is disposed substantially in the middle along the length direction of the housing 102, and is disposed below the first communication port 281 on the main baffle assembly 231 such that fluid can flow into the dispenser receptacle 226 through the first communication port 281 and the dispenser inlet 222. The lower portion of the dispenser housing 225 is provided with a plurality of dispenser outlets 223. Specifically, a plurality of dispenser outlets 223 are spaced apart along the length of the housing 102 such that fluid flowing in the dispenser plenum 226 is able to flow along the length of the housing 102 and into the second plenum 206 through the dispenser outlets 223. In the example of the present application, the dispenser outlet 223 is in the form of a narrow strip. Those skilled in the art will appreciate that the dispenser outlet 223 may be of any shape.

As shown in fig. 2, the fluid guiding structure of the heat exchanger 100 further includes a second inlet pipe expander 297. The second inlet tube expander 297 is disposed in the first plenum 204. Which is disposed over the second communication port 282 and is connected to the second inlet pipe 114 and the main baffle assembly 231. Specifically, the second inlet tube expander 297 is generally flared. The upper part of which is smaller and the lower part is larger. The upper portion of which is connected to the second inlet pipe 114 and the opening 285 of which is in communication with the outlet of the second inlet pipe 114. The lower portion thereof is covered on the main shutter assembly 231, and the opening 286 of the lower portion thereof communicates with the second communication port 282. . The opening 285 at the upper part of the second inlet pipe amplifier 297 has the same size as the outlet of the second inlet pipe 114, and the diameters thereof are all the first diameter d1. The diameter of the opening 286 of the lower portion of the second inlet tube expander 297 is the second diameter d2. The second diameter d2 is larger than the first diameter d1 so that the fluid flowing in from the second inlet pipe 114 can reduce the flow velocity in the second inlet pipe expander 297.

As shown in fig. 2 and 4, the fluid guiding structure of the heat exchanger 100 further includes a buffer 250. The damper 250 is disposed below the main shutter assembly 231 and below the second communication port 282. In an embodiment of the present application, the buffer 250 is a buffer plate. The buffer plate has a buffer length extending in the length direction of the housing 102, and has a buffer width extending in the width direction of the housing 102. The shape of the buffer plate is similar to the shape of the main baffle assembly 231. Specifically, the baffle is generally stepped with lower ends and higher middle portions in the radial cross section of the housing 102. Further, in a radial cross section of the housing 102, both sides of the buffer plate in the width direction are tilted upward and connected to the main barrier assembly 231. The buffer length and the buffer width of the buffer plate are configured to cover the second communication port 282, so that the fluid flowing in from the second communication port 282 can flow in the direction of the buffer length of the buffer plate to enter the second receiving chamber 206. In one example, the width of the buffer plate is d3. Wherein d3:d2 is 1:1 or more and 5:1 or less, so that the buffer plate can cover the second communication port 282. In another example, the buffer plate has a first distance h1 from the second communication port 282. In yet another example, the width of the dispenser 221 in the width direction of the housing 102 is d4. Wherein d2:d4 is greater than or equal to 2:1 and less than or equal to 5:1, such that the dispenser 221 does not excessively block the flow of fluid through the opening 286 of the lower portion of the second inlet tube expander 297.

It should be noted that the buffer plate is also provided with a channel 401 along its buffer length to accommodate a portion of the dispenser 221. The dispenser outlet 223 of the dispenser 221 is disposed at a lower portion of the buffer plate so that the fluid flowing in from the first inlet pipe 112 can flow into the second chamber 206 through the dispenser outlet 223 without being affected by the buffer plate.

As shown in fig. 3-4, the fluid guiding structure of the heat exchanger 100 further includes a first additional plate 333 and a second additional plate 334. The first and second additional plates 333 and 334 are connected to the main barrier assemblies 231, respectively. Specifically, the first and second additional plates 333 and 334 extend along the length direction of the housing 102, and are disposed substantially vertically in the second cavity 206. The first and second additional plates 333 and 334 are connected to lower portions of the stepped main baffle assembly, respectively, and are formed to extend generally downward.

As shown in fig. 2-4, heat exchanger 100 also includes a heat exchange tube bundle 210. Heat exchange tube bundle 210 is disposed in second plenum 206 and is positioned below first inlet tube 112, second inlet tube 114, and first outlet tube 124, and above second outlet tube 122. Specifically, heat exchange tube bundle 210 includes a first set of heat exchange tubes 261 and a second set of heat exchange tubes 262. The first set of heat exchange tubes 261 includes a first number of heat exchange tubes, the second set of heat exchange tubes 262 includes a second number of heat exchange tubes, and a ratio of the first number to the second number is greater than 2:1. The first group of heat exchange tubes 261 is disposed substantially in the middle of the second chamber 206 and extends in the longitudinal direction of the housing 102. The left ends of the heat exchange tubes in the first group of heat exchange tubes 261 are communicated with the communication cavity 203 on the left side of the heat exchanger 100, and the right ends of the heat exchange tubes in the first group of heat exchange tubes 261 are communicated with the outlet cavity 212 on the right side of the heat exchanger 100. The second group of heat exchange tubes 262 is disposed substantially at the lower portion of the second chamber 206 and extends in the longitudinal direction of the housing 102. The left ends of the heat exchange tubes in the second group of heat exchange tubes 262 are communicated with the communication cavity 203 on the left side of the heat exchanger 100, and the right ends of the second group of heat exchange tubes 262 are communicated with the inlet accommodating cavity 213 on the right side of the heat exchanger 100. In this way, the heat exchange fluid may enter the heat exchanger 100 from the inlet plenum 213 at the right side of the heat exchanger 100, flow through the second set of heat exchange tubes 262, the communication plenum 203, and the first set of heat exchange tubes 261 in that order, and then flow out of the heat exchanger 100 from the outlet plenum 212. As the heat exchange fluid flows in the first set of heat exchange tubes 261 and the second set of heat exchange tubes 262, it is able to exchange heat with the fluid in the second plenum 206. Further, the inner diameter of the cylinder 131 is D. The bottom of the first set of heat exchange tubes 261 is a second distance h2 from the top of the second set of heat exchange tubes 262. That is, the distance between the bottom of the lowermost heat exchange tube of the first group of heat exchange tubes 261 and the top of the uppermost heat exchange tube of the second group of heat exchange tubes 262 is the second distance h2. Wherein the ratio of the second distance h2 to the inner diameter D is less than 1:2.

Thus, the fluid directing structure is configured to define different flow paths of the heat exchanger 100 in the condenser operating mode and in the evaporator operating mode, respectively. When heat exchanger 100 is in the evaporator mode of operation, the fluid directing structure directs fluid flowing from first inlet tube 112 to exchange heat with fluid in heat exchange tube bundle 210 to vaporize it into a gas and directs the vaporized gas to exit heat exchanger 100 via first outlet tube 124. When heat exchanger 100 is in the condenser operating mode, the fluid directing structure directs the fluid flowing in from second inlet tube 114 to exchange heat with the fluid in heat exchange tube bundle 210 to condense it into a liquid, and the liquid resulting from the condensation then exits heat exchanger 100 via second outlet tube 122. This will be described in detail below in connection with the different modes of operation shown in fig. 5A-5B and fig. 6A-6B.

The heat exchanger 100 shown in fig. 1-4 has an evaporator mode of operation and a condenser mode of operation. When the heat exchanger 100 is in the evaporator mode of operation, the heat exchanger 100 is used as an evaporator. When the heat exchanger 100 is in the condenser operation mode, the heat exchanger 100 is used as a condenser. The flow path of fluid in the heat exchanger 100 when the heat exchanger 100 is in the evaporator mode of operation and the condenser mode of operation is described below in connection with fig. 5A-5B and fig. 6A-6B, respectively.

Fig. 5A is an axial cross-sectional view of the heat exchanger shown in fig. 1, illustrating the path of movement of fluid over the axial cross-sectional view of the heat exchanger when the heat exchanger 100 is in the evaporator mode of operation. Fig. 5B is a cross-sectional view of the heat exchanger of fig. 1 taken along line A-A of fig. 2, illustrating the path of fluid movement in an axial cross-sectional view of the heat exchanger when the heat exchanger 100 is in the evaporator mode of operation. As shown in fig. 5A-5B, when the heat exchanger 100 is in the evaporator mode of operation, fluid (e.g., a gas-liquid mixture) flows into the heat exchanger 100 from the first inlet tube 112. The fluid then flows into the distributor volume 226 of the distributor 221 through the first inlet pipe expander 291, the first communication port 281 on the main baffle assembly 231, and the distributor inlet 222 in sequence. Since the dispenser receptacle 226 extends along the length of the housing 102, the fluid contained in the dispenser receptacle 226 also moves along the length of the housing 102. That is, in the length direction of the housing 102, the fluid flows from the middle to both sides. During the flow, since the lower portion of the distributor 221 is provided with a plurality of distributor outlets 223, the fluid may flow downward. It can be seen that since the plurality of distributor outlets 223 are disposed along the length of the housing 102, fluid is able to flow downwardly more uniformly along the length of the housing 102 and through the first set of heat exchange tubes 261 from top to bottom. Flowing in the first set of heat exchange tubes 261 is a higher temperature heat exchange fluid. The fluid contacts the first set of heat exchange tubes 261 and exchanges heat with the heat exchange fluid in the first set of heat exchange tubes 261. Specifically, during the downward flow of fluid in contact with the first set of heat exchange tubes 261, the fluid is distributed over the uppermost row of heat exchange tubes and forms a liquid film on the uppermost row of tube heat tubes for evaporation. The liquid fluid which is not evaporated drops onto the next row of heat exchange tubes to continue evaporation. The liquid fluid may flow all the way down and form a liquid film at the first set of heat exchange tubes 261 for evaporation. The fluid that is not evaporated on the first group of heat exchange tubes 261 flows downward to contact the second group of heat exchange tubes 262, which exchanges heat with the heat exchange fluid in the second group of heat exchange tubes 262, increases in temperature, and evaporates. Since the first additional plate 333 and the second additional plate 334 are disposed at both sides of the first group of heat exchange tubes 261, the fluid evaporated to the gas at the first group of heat exchange tubes 261 continues to flow downward until the fluid evaporated to the gas flows upward after passing over the first additional plate 333 and the second additional plate 334. In other words, in the radial direction of the housing 102, the fluid evaporated into gas flows downward beyond the first group of heat exchange tubes 261 to both sides and then flows upward. The fluid vaporized into gas passes through the plurality of channels 241 in the main baffle assembly 231 and enters the first plenum 204 and then exits the heat exchanger 100 through the first outlet tube 124. Another portion of the fluid vaporized into gas at the second set of heat exchange tubes 262 flows upward and through the plurality of channels 241 in the main baffle assembly 231 into the first plenum 204 and then out of the heat exchanger 100 through the first outlet tube 124. It should be noted that, when the heat exchanger 100 is in the evaporator operation mode, the liquid fluid can be deposited at the bottom of the second cavity 206 and exchange heat with the second set of heat exchange tubes 262 to evaporate.

Fig. 6A is an axial cross-sectional view of the heat exchanger shown in fig. 1, illustrating the path of fluid movement on the axial cross-sectional view of the heat exchanger when the heat exchanger 100 is in the condenser mode of operation. Fig. 6B is a cross-sectional view of the heat exchanger of fig. 1 taken along line B-B of fig. 2, illustrating the path of fluid movement in an axial cross-sectional view of the heat exchanger when the heat exchanger 100 is in a condenser mode of operation. As shown in fig. 6A-6B, when the heat exchanger 100 is in the condenser mode of operation, fluid (e.g., a relatively fast flow rate of gas) flows into the heat exchanger 100 from the second inlet tube 114. The fluid then enters the second plenum 206 through the second inlet tube expander 297, the second communication port 282 in the main baffle assembly 231 in sequence. Because of the high velocity of the fluid, the fluid flowing into the second volume 206 directly impacts the damper 250. Since the width direction of the damper 250 is connected to the main barrier assembly 231, the fluid can move in the length direction of the housing 102 and move downward beyond the damper 250. The fluid then flows to the first set of heat exchange tubes 261. Flowing in the first set of heat exchange tubes 261 is a lower temperature heat exchange fluid. The fluid contacts the first set of heat exchange tubes 261 and exchanges heat with the heat exchange fluid in the first set of heat exchange tubes 261. During the downward flow of fluid into contact with the first set of heat exchange tubes 261, the fluid condenses into a liquid and accumulates at the bottom of the second chamber 206. When the fluid condensed into liquid accumulates at the bottom of the second volume 206, it can cause the second set of heat exchange tubes 262 to be immersed in the liquid. Because the lower temperature heat exchange fluid flows in the second set of heat exchange tubes 262, the fluid condensed into a liquid will continue to exchange heat with the heat exchange fluid in the second set of heat exchange tubes 262, further reducing the temperature. Subsequently, the fluid condensed into liquid may flow out of the heat exchanger 100 from the second outlet pipe 122.

Fig. 7 is a system diagram of a heat pump system using the heat exchanger 100 of the present application to show components of the heat pump system and their connection relationship. As shown in fig. 1, the heat pump system includes a compressor 701, a heat exchanger 100, a second heat exchanger 702, a four-way valve 722, a throttle device 703, and several other valves as will be described below. The connections between the various components shown in fig. 7, including the compressor 701, the second heat exchanger 702, the heat exchanger 100, the four-way valve 722, the throttle 703 and the other various valves, represent connecting lines. The compressor 701 has a suction port 711, a discharge port 712, and a lubricant inlet 713. The second heat exchanger 702 has a heat exchanger first port 741 and a heat exchanger second port 742. The four-way valve 722 has a first port 731, a second port 732, a third port 733, and a fourth port 734. The restriction 703 has a restriction first port 743 and a restriction second port 744. Specifically, the discharge port 712 of the compressor 701 is connected to the first port 731 of the four-way valve 722 through a connection line. The second port 732 of the four-way valve 722 is connected to the heat exchanger first port 741 of the second heat exchanger 702 via a connecting line. The heat exchanger second port 742 of the second heat exchanger 702 is connected to the throttle device first port 743 of the throttle device 703 via a connecting line. The throttle device second port 744 of the throttle device 703 is connected to the first inlet pipe 112 and the second outlet pipe 122 of the heat exchanger 100 by connecting lines. The third port 733 of the four-way valve 722 is connected to the intake port 711 of the compressor 701 through a connection line. The fourth port 734 of the four-way valve 722 is connected to the second inlet pipe 114 and the first outlet pipe 124 of the heat exchanger 100 by connecting lines. The lubricant inlet 713 of the compressor 701 is connected to the discharge pipe 125 of the heat exchanger 100 by a connecting line. The four-way valve 722 has a pair of passages and has a first state and a second state. When the four-way valve 722 is in different states, a pair of passages can communicate with different ports on the four-way valve 722. Wherein, when the four-way valve 722 is in the first state, a pair of passages can communicate the first port 731 and the fourth port 734, and the second port 732 and the third port 733. When the four-way valve 722 is in the second state, a pair of passages can communicate the first port 731 with the second port 732 and the third port 733 with the fourth port 734.

In addition, the heat pump system further includes a first check valve 751, a second check valve 752, a third check valve 753, and a fourth check valve 754. Wherein the first one-way valve 751 is disposed on a connecting line between the throttle device second port 744 of the throttle device 703 and the first inlet pipe 112 of the heat exchanger 100 and is configured to enable fluid flow from the throttle device second port 744 to the first inlet pipe 112. The second check valve 752 is disposed on the connection between the throttle device second port 744 of the throttle device 703 and the second outlet pipe 122 of the heat exchanger 100 and is configured to enable fluid flow from the second outlet pipe 122 to the throttle device second port 744. A third check valve 753 is disposed on the connection line between the fourth port 734 of the four-way valve 722 and the second inlet pipe 114 of the heat exchanger 100 and is configured to enable fluid to flow from the fourth port 734 to the second inlet pipe 114. The fourth check valve 754 is disposed on a connection line between the fourth port 734 of the four-way valve 722 and the first outlet pipe 124 of the heat exchanger 100 and is configured to enable fluid to flow from the first outlet pipe 124 to the fourth port 734.

Those skilled in the art will appreciate that the first 751, second 752, third 753 and fourth 754 check valves may also be provided as other types of valves that enable controlled communication or disconnection between the upstream and downstream valves.

The heat pump system can realize a cooling mode and a heating mode. When the heat pump system is in the cooling mode, the heat exchanger 100 is in the evaporator mode of operation. When the heat pump system is in the heating mode, the heat exchanger 100 is in the condenser operating mode. The flow path of fluid in the heat pump system when the heat pump system is in the cooling mode and the heating mode, respectively, is described below in connection with fig. 8A-8B.

Fig. 8A is a system diagram of the heat pump system shown in fig. 7 in a cooling mode. As shown in fig. 8A, when the heat pump system is in the cooling mode, the four-way valve 722 is in the second state. That is, a pair of passageways can communicate the first port 731 and the second port 732, and the third port 733 and the fourth port 734. Specifically, the high-temperature and high-pressure gaseous refrigerant flowing out of the discharge port 712 of the compressor 701 flows to the second heat exchanger 702 through the first port 731, the second port 732 of the four-way valve 722, and the heat exchanger first port 741 of the second heat exchanger 702 in this order. The high-temperature and high-pressure gaseous refrigerant exchanges heat with air in the second heat exchanger 702, thereby changing the high-temperature and high-pressure gaseous refrigerant into a high-pressure liquid refrigerant. The high pressure liquid refrigerant flows from the second heat exchanger 702, through the restriction 703 to become a low temperature low pressure refrigerant, and then flows into the heat exchanger 100 through the first check valve 751 and the first inlet line 112 of the heat exchanger 100. In the heat exchanger 100, a low-temperature low-pressure refrigerant exchanges heat with a fluid having a higher temperature at the user side, thereby reducing the temperature of the fluid at the user side to provide the fluid having a lower temperature at the user side (for example, for providing air-conditioning cold water). The low-temperature low-pressure refrigerant changes into a low-pressure gaseous refrigerant after heat exchange with the user side fluid in the heat exchanger 100. The low-pressure gaseous refrigerant flows out of the first outlet pipe 124, sequentially passes through the fourth check valve 754, the fourth port 734 of the four-way valve 722 and the third port 733 of the four-way valve 722, and then enters the compressor 701 again through the suction port 711 of the compressor 701, and becomes high-temperature high-pressure gaseous refrigerant, so that the circulation of the refrigerant is completed.

Fig. 8B is a system diagram of the heat pump system shown in fig. 7 in a heating mode. As shown in fig. 8B, when the heat pump system is in the heating mode, the four-way valve 722 is in the first state. That is, a pair of passageways can communicate the first port 731 and the fourth port 734, and the second port 732 and the third port 733. Specifically, the high-temperature and high-pressure gaseous refrigerant flowing out of the discharge port 712 of the compressor 701 flows into the heat exchanger 100 through the first port 731 of the four-way valve 722, the fourth port 734 of the four-way valve 722, the third check valve 753, and the second inlet pipe 114 of the heat exchanger 100 in this order. In the heat exchanger 100, the high-temperature and high-pressure gaseous refrigerant exchanges heat with a fluid having a lower temperature at the user side, thereby raising the temperature of the fluid at the user side to provide the fluid having a higher temperature to the user (for example, for providing air-conditioning hot water). The high-temperature high-pressure gaseous refrigerant is changed into a high-pressure liquid refrigerant after heat exchange with the user side fluid in the heat exchanger 100. The high-pressure liquid refrigerant flows out of the heat exchanger 100, passes through the second outlet pipe 122 and the second check valve 752 in this order, and then flows through the throttle 703. The high pressure liquid refrigerant flows through the restriction 703 to be a low temperature low pressure refrigerant, which then flows through the heat exchanger second port 742 of the second heat exchanger 702 to the second heat exchanger 702. The low-temperature low-pressure refrigerant exchanges heat with air in the second heat exchanger 702, thereby changing the low-temperature low-pressure refrigerant into a low-pressure gaseous refrigerant. The low-pressure gaseous refrigerant sequentially passes through the second port 732 and the third port 733 of the four-way valve 722 and then enters the compressor 701 again from the suction port 711 of the compressor 701, and becomes high-temperature high-pressure gaseous refrigerant, so that the circulation of the refrigerant is completed.

Thus, the heat exchanger 100 of the present application can be used as both an evaporator and a condenser. When the heat exchanger 100 of the present application is used as an evaporator, there is at least an advantage in that, first, the heat exchanger 100 of the present application can ensure a higher heat exchange efficiency because it can achieve falling film evaporation with a higher heat exchange efficiency to form a liquid film of fluid in the first group of heat exchange tubes 261 of the second chamber 206. Second, the heat exchanger 100 of the present application also ensures that the fluid exiting the first outlet tube 124 is free of liquid, as the fluid flow path defined by the fluid directing structure allows for better separation of the gas from the liquid. In particular, the arrangement of the first and second additional plates 333, 334 and the plurality of channels 241 enables the direction of movement of the fluid evaporated to a gas to be varied a plurality of times, and the gas can better flow out of the heat exchanger 100 in a defined path due to the different densities of the liquid and the gas, while the liquid is left in the second chamber 206 for evaporation. Third, the heat exchanger 100 of the present application facilitates the draining of lubricant. Specifically, the fluid flowing in from the first inlet pipe 112 of the heat exchanger 100 includes a refrigerant and a lubricant. In one aspect, lubricant is retained in the second volume 206 after the refrigerant fluid evaporates into a gas exiting the heat exchanger 100 from the first outlet tube 124. Lubricant may be deposited at the bottom of the second volume 206. On the other hand, since the ratio of the first number of heat exchange tubes to the second number of heat exchange tubes is greater than 2:1, the liquid-full area ratio in the heat exchanger 100 is small, and the amount of liquid (which includes refrigerant liquid and lubricant) that can be contained in the bottom is small. Thereby, the lubricant discharged from the heat exchanger 100 has a high concentration. When the heat exchanger 100 of the present application is used as a condenser, the heat exchanger 100 can store a fluid condensed into a liquid, thereby avoiding the provision of an external reservoir. In particular, in the conventional heat pump system, the heat pump system needs to provide a refrigerant reservoir for storing the refrigerant because the amount of the refrigerant stored inside is not uniform when the heat exchanger is used as a condenser and an evaporator in the heat pump system. The heat pump system of the present application does not require a refrigerant reservoir to be provided. This is because the bottom of the first group of heat exchange tubes 261 has the second distance h2 from the top of the second group of heat exchange tubes 262, and thus there are enough chambers in the second chamber 206 to accommodate the refrigerant. The heat exchanger 100 is capable of automatically adjusting the amount of refrigerant contained in the second volume 206 in response to the demand for refrigerant by the heat pump system in different modes. This greatly simplifies the components and connections of the heat pump system.

It should be noted that, although a basic heat pump system is shown in fig. 7, those skilled in the art will understand that the heat pump system may be implemented by various connection relationships, and the heat pump system may also include other components such as an economizer.

Although only a few features of the application have been shown and described, many modifications and changes will occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the application.

Claims (11)

1. A heat exchanger (100), characterized in that the heat exchanger (100) has an evaporator operation mode and a condenser operation mode, wherein the heat exchanger (100) comprises:

-a housing (102), the housing (102) having a cavity (202);

-a heat exchange tube bundle (210), said heat exchange tube bundle (210) being housed in said cavity (202);

A first inlet tube (112), a second inlet tube (114), a first outlet tube (124) and a second outlet tube (122), the first inlet tube (112), the second inlet tube (114), the first outlet tube (124) and the second outlet tube (122) being connected to the housing (102) and in fluid communication with the plenum (202), wherein the first inlet tube (112), the second inlet tube (114) and the first outlet tube (124) are located above the heat exchange tube bundle (210), the second outlet tube (122) is located below the heat exchange tube bundle (210), and

A fluid guiding structure disposed in the cavity (202) and configured to define different flow paths of the heat exchanger (100) in the condenser and evaporator modes of operation, respectively;

Wherein, when the heat exchanger (100) is in the evaporator operation mode, the fluid directing structure directs fluid flowing in from the first inlet tube (112) to exchange heat with fluid in the heat exchange tube bundle (210) to evaporate it into a gas and directs the evaporated gas to exit the heat exchanger (100) via the first outlet tube (124);

Wherein, when the heat exchanger (100) is in the condenser operating mode, the fluid directing structure directs fluid flowing in from the second inlet tube (114) to exchange heat with fluid in the heat exchange tube bundle (210) to condense it into liquid, and subsequently the condensed liquid exits the heat exchanger (100) via the second outlet tube (122).

2. The heat exchanger (100) of claim 1, wherein the fluid directing structure comprises:

A main baffle assembly (231), the main baffle assembly (231) being disposed in the vessel (202) and dividing the vessel (202) into a first vessel (204) at an upper portion and a second vessel (206) at a lower portion, wherein the heat exchange tube bundle (210) is disposed in the second vessel (206), the first outlet tube (124) being in communication with the first vessel (204), the second outlet tube (122) being in communication with the second vessel (206);

Wherein, a first communication port (281) and a second communication port (282) are arranged on the main baffle assembly (231), and the first inlet pipe (112) and the second inlet pipe (114) are respectively communicated with the second containing cavity (206) through the first communication port (281) and the second communication port (282);

Wherein the fluid directing structure directs fluid flowing from the first inlet tube (112) through the first communication port (281) into the second plenum (206) when the heat exchanger (100) is in an evaporator mode of operation and directs fluid flowing from the second inlet tube (114) through the second communication port (282) into the second plenum (206) when the heat exchanger (100) is in a condenser mode of operation, and

Wherein, a plurality of channels (241) are arranged on the main baffle assembly (231), and the first containing cavity (204) and the second containing cavity (206) can be in fluid communication through the channels (241).

3. The heat exchanger (100) of claim 2, wherein the fluid directing structure further comprises:

-a distributor (221), said distributor (221) being arranged between said first inlet pipe (112) and said heat exchange tube bundle (210);

the dispenser (221) comprises a dispenser housing (225), a dispenser receptacle (226) defined by the dispenser housing (225), and a dispenser inlet (222) and a plurality of dispenser outlets (223) formed in the dispenser housing (225), the dispenser inlet (222) and the plurality of dispenser outlets (223) each being in communication with the dispenser receptacle (226);

the distributor (221) is configured to pass fluid flowing in from the first inlet tube (112) into the distributor plenum (226) via the distributor inlet (222) and distribute from the plurality of distributor outlets (223) to the heat exchange tube bundle (210).

4. A heat exchanger (100) according to claim 3, wherein:

The distributor (221) is arranged below the main baffle assembly (231), and the first inlet pipe (112) is communicated with the distributor inlet (222) through the first communication opening (281) on the main baffle assembly (231), so that fluid flowing in by the first inlet pipe (112) can sequentially flow through the first communication opening (281), the distributor inlet (222), the distributor accommodating cavity (226) and the distributor outlet (223) and then enter the second accommodating cavity (206).

5. The heat exchanger (100) of claim 4, wherein the fluid directing structure further comprises:

A buffer (250), the buffer (250) being arranged in the second cavity (206) and being disposed between the main baffle assembly (231) and the heat exchanger tube bundle (210), the buffer (250) being disposed below the second communication port (282) and having a first distance from the second communication port (282) that enables fluid from the second communication port (282) to enter the second cavity (206).

6. The heat exchanger (100) of claim 5, wherein:

a plurality of distributor outlets (223) of the distributor (221) are located below the buffer (250).

7. The heat exchanger (100) of claim 5, wherein:

The damper (250) is a damper plate having a damper length extending in a length direction of the housing (102) and having a damper width extending along a width of the housing (102);

Wherein the buffer plate is connected to the main baffle assembly (231) at both ends of the width direction of the housing (102) so that the fluid entering the second accommodating chamber (206) from the second communication port (282) flows along the length direction of the housing (102) and then flows to the heat exchange tube bundle (210).

8. The heat exchanger (100) of claim 7, wherein:

the buffer length and the buffer width of the buffer plate are configured to cover the second communication port (282).

9. The heat exchanger (100) according to claim 1, wherein:

the heat exchange tube bundle (210) comprises a first group of heat exchange tubes (261) and a second group of heat exchange tubes (262), wherein the first group of heat exchange tubes (261) are positioned above the second group of heat exchange tubes (262);

Wherein the first set of heat exchange tubes (261) comprises a first number of heat exchange tubes and the second set of heat exchange tubes (262) comprises a second number of heat exchange tubes;

Wherein the ratio of the first number to the second number is greater than 2:1.

10. The heat exchanger (100) of claim 9, wherein:

the bottom of the first group of heat exchange tubes (261) is a second distance (h 2) from the top of the second group of heat exchange tubes (262);

-the housing (102) is circular in cross section, having an inner diameter (D);

Wherein the ratio of the second distance (h 2) to the inner diameter (D) is less than 1:2.

11. A heat pump system, characterized by:

The heat pump system comprising a heat exchanger (100) according to any one of claims 1 to 10;

The heat pump system is provided with a refrigerating operation mode and a heating operation mode, when the heat pump system is in the refrigerating operation mode, the heat exchanger (100) works as an evaporator, and when the heat pump system is in the heating operation mode, the heat exchanger (100) works as a condenser.