EP4621316A1

EP4621316A1 - Heat exchanger unit and air conditioning system

Info

Publication number: EP4621316A1
Application number: EP25163983.7A
Authority: EP
Inventors: Yongliang Hu
Original assignee: Carrier Corp
Current assignee: Carrier Corp
Priority date: 2024-03-20
Filing date: 2025-03-14
Publication date: 2025-09-24
Also published as: US20250297809A1

Abstract

This invention provides a heat exchanger unit and an air conditioning system. The heat exchanger unit includes: a first heat exchanger (1), including a first housing (11) provided with a first refrigerant inlet and a first refrigerant outlet, a first refrigerant flow passage (111) formed between the first refrigerant inlet and the first refrigerant outlet, and a first heat exchanging tube bundle (12) disposed in the first housing (11); a second heat exchanger (2), including a second housing (21) provided with a second refrigerant inlet and a second refrigerant outlet, a second refrigerant flow passage (211) formed between the second refrigerant inlet and the second refrigerant outlet, and a third heat exchanging tube bundle (22) disposed in the second housing (21) and having an inlet in communication with an outlet of the first heat exchanging tube bundle (12); a third heat exchanger (6), including a third refrigerant flow passage (61) in communication with the first refrigerant flow passage (111), and a first heat exchanging flow passage (62); and a fourth heat exchanger (7), including a fourth refrigerant flow passage (71) in communication with the second refrigerant flow passage (211), and a second heat exchanging flow passage (72) and having an inlet in communication with an outlet of the first heat exchanging flow passage (61). This invention can reduce the temperature of the refrigerant entering the second heat exchanger, increase the degree of supercooling of the refrigerant, and improve the heating effect.

Description

Priority Claim

This application claims priority to Chinese Patent Application No. CN202410323799.1, entitled "Heat Exchanger Unit and Air Conditioning System," filed with the China Patent Office on March 20, 2024 , the entire contents of which are incorporated herein by reference.

Technical Field

This invention relates to a field of refrigeration equipment, and in particular to a heat exchanger unit and an air conditioning system.

Background Art

For the air-conditioning chiller-heater unit or chiller unit, heat generated by a high-temperature and high-pressure gaseous refrigerant in a condenser during heat release can raise a temperature of the water to a higher temperature. In order to ensure good unit efficiency, it needs to be ensured that the refrigerant at an outlet of the condenser can have a certain degree of supercooling or a lower liquid refrigerant temperature. However, in a heat exchanger of an air conditioning system illustrated in FIG. 1, waterways of a first condenser 100 and a second condenser 200 are connected in series, and the entering water temperature of the second condenser 200 (the leaving water temperature of the first condenser 100) is higher, so that the degree of supercooling of the second condenser 200 is limited, and it is difficult for the refrigerant at the outlet of the second condenser 200 to obtain a larger degree of supercooling or a lower liquid refrigerant temperature, which affects the overall heating performance of the air-conditioning chiller-heater unit or chiller unit.

Summary of the Invention

Embodiments of this invention provide a heat exchanger unit and an air conditioning system, which are used for at least solving or relieving partial problems in the prior art.
A first aspect of this invention provides a heat exchanger unit, including:

a first heat exchanger, including a first housing provided with a first refrigerant inlet and a first refrigerant outlet, a first refrigerant flow passage formed between the first refrigerant inlet and the first refrigerant outlet, and a first heat exchanging tube bundle disposed in the first housing;
a second heat exchanger, including a second housing provided with a second refrigerant inlet and a second refrigerant outlet, a second refrigerant flow passage formed between the second refrigerant inlet and the second refrigerant outlet, and a third heat exchanging tube bundle disposed in the second housing, and having an inlet in communication with an outlet of the first heat exchanging tube bundle;
a third heat exchanger, including a third refrigerant flow passage in communication with the first refrigerant flow passage, and a first heat exchanging flow passage; and
a fourth heat exchanger, including a fourth refrigerant flow passage in communication with the second refrigerant flow passage, and a second heat exchanging flow passage having an inlet in communication with an outlet of the first heat exchanging flow passage.

In an optional technical solution, the third heat exchanger is disposed in the first housing, the first heat exchanging flow passage is a second heat exchanging tube bundle disposed in the first housing, the second heat exchanging tube bundle is disposed closer to the first refrigerant outlet than the first heat exchanging tube bundle, and the third refrigerant flow passage and the first refrigerant flow passage together form an empty space inside the first housing, and
the fourth heat exchanger is disposed in the second housing, the second heat exchanging flow passage is a fourth heat exchanging tube bundle disposed in the second housing, the fourth heat exchanging tube bundle is disposed closer to the second refrigerant outlet than the third heat exchanging tube bundle, and the fourth refrigerant flow passage and the second refrigerant flow passage together form an empty space inside the second housing.
Optionally, the first heat exchanger further includes

first housing tube sheets respectively disposed at two inner ends of the first housing and fixing the first heat exchanging tube bundle and the second heat exchanging tube bundle,
first heat exchanger end covers respectively disposed at two ends of the first housing,
first chambers enclosed by the first heat exchanger end covers and the first housing tube sheets disposed corresponding to the first heat exchanger end covers, and
at least one first separator disposed in the first chamber and dividing the first chamber into a first heat exchanging tube bundle chamber in communication with the first heat exchanging tube bundle and a second heat exchanging tube bundle chamber in communication with the second heat exchanging tube bundle.

Optionally, the second heat exchanger further includes

second housing tube sheets respectively disposed at two inner ends of the second housing and fixing the third heat exchanging tube bundle and the fourth heat exchanging tube bundle,
second heat exchanger end covers respectively disposed at two ends of the second housing,
second chambers enclosed by the second heat exchanger end covers and the second housing tube sheets disposed corresponding to the second heat exchanger end covers, and
at least one second separator disposed in the second chamber and dividing the second chamber into a first accommodating chamber in communication with the third heat exchanging tube bundle and a second accommodating chamber in communication with the fourth heat exchanging tube bundle.

Optionally, the second heat exchanger further includes
two third separators disposed in the second chamber and dividing the second chamber into a third accommodating chamber in communication with the third heat exchanging tube bundle, a fourth accommodating chamber in communication with the fourth heat exchanging tube bundle, and a fifth accommodating chamber between the third accommodating chamber and the fourth accommodating chamber.
Optionally, the fourth accommodating chamber is in communication with the first heat exchanging tube bundle chamber through a pipeline,

the first heat exchanging tube bundle chamber is in communication with the fifth accommodating chamber through a pipeline, and
the fifth accommodating chamber is in communication with the third accommodating chamber through the third heat exchanging tube bundle.

Optionally, the pipeline through which the fourth accommodating chamber is in communication with the first heat exchanging tube bundle chamber is provided with a first water pump.
Optionally, the second heat exchanging tube bundle chamber is in communication with the fifth accommodating chamber through a pipeline,

the fourth heat exchanging tube bundle is in communication with the first heat exchanging tube bundle chamber through a pipeline,
the first heat exchanging tube bundle chamber is in communication with the fifth accommodating chamber through a pipeline, and
the fifth accommodating chamber is in communication with the third accommodating chamber through the third heat exchanging tube bundle.

Optionally, the pipeline through which the fourth heat exchanging tube bundle is in communication with the first heat exchanging tube bundle chamber is provided with a second water pump.
Optionally, each of the first heat exchanger and the second heat exchanger is a condenser.
Optionally, an outlet of the fourth heat exchanging tube bundle is in communication with an inlet of the third heat exchanging tube bundle through a pipeline.
Optionally, the pipeline through which the outlet of the fourth heat exchanging tube bundle is in communication with the inlet of the third heat exchanging tube bundle is provided with a third water pump.
Optionally, the third heat exchanger is disposed outside the first housing, and an inlet of the third refrigerant flow passage is in communication with the first refrigerant outlet. The fourth heat exchanger is disposed outside the second housing, and an inlet of the fourth refrigerant flow passage is in communication with the second refrigerant outlet.
Optionally, a pipeline through which the first heat exchanging flow passage is in communication with the second heat exchanging flow passage is provided with a fourth water pump.
Optionally, the outlet of the second heat exchanging flow passage is in communication with an inlet of the third heat exchanging tube bundle through a pipeline.
Optional, the pipeline through which the outlet of the second heat exchanging flow passage is in communication with the inlet of the third heat exchanging tube bundle is provided with a fifth water pump.
A second aspect of this invention provides an air conditioning system, including the above heat exchanger unit as a condenser.

Descriptions of the Drawings

Certain exemplary embodiments will now be described in greater detail by way of example only and with reference to the accompanying drawings in which:

FIG. 1 is a schematic structural diagram of a heat exchanger unit in the prior art.
FIG. 2 is a schematic structural diagram of a first heat exchanger unit.
FIG. 3 is a schematic structural diagram of a second heat exchanger unit.
FIG. 4 is a schematic structural diagram of a third heat exchanger unit.
FIG. 5 is a schematic structural diagram of a fourth heat exchanger unit.
FIG. 6 is a schematic structural diagram of a fifth heat exchanger unit.
FIG. 7 is a schematic structural diagram of a sixth heat exchanger unit.

List of Reference Numerals:

First condenser 100, second condenser 200.

First heat exchanger 1, first housing 11, first heat exchanging tube bundle 12, first tube body 121, second tube body 122, second heat exchanging tube bundle 13 (first heat exchanging flow passage 13), first housing tube sheet 14, first heat exchanger end cover 15, first chamber 16, first heat exchanging tube bundle chamber 161, chamber 161A, chamber 161B, second heat exchanging tube bundle chamber 162, third heat exchanging tube bundle chamber 163, fourth heat exchanging tube bundle chamber 164, first separator 17, fourth separator 18, fifth separator 19.
Second heat exchanger 2, second housing 21, third heat exchanging tube bundle 22, third tube body 221, fourth tube body 222, fourth heat exchanging tube bundle 23 (second heat exchanging flow passage 23), second housing tube sheet 24, second heat exchanger end cover 25, second chamber 26, first accommodating chamber 261, accommodating chamber 261A, accommodating chamber 261B, second accommodating chamber 262, third accommodating chamber 263, fourth accommodating chamber 264, fifth accommodating chamber 265, second separator 27, third separator 28, sixth separator 29, first water pump 31, second water pump 32, third water pump 33, fourth water pump 34.
First refrigerant flow passage 111, second refrigerant flow passage 211, third heat exchanger 6, third refrigerant flow passage 61, first heat exchanging flow passage 62, fourth heat exchanger 7, fourth refrigerant flow passage 71, second heat exchanging flow passage 72.

Detailed Description

The technical solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this invention, and obviously, the described embodiments are merely a part of the embodiments of this invention, and are not all embodiments. Based on the embodiments in this invention, all other embodiments obtained by a person skilled in the art without creative work fall within the protection scope of this invention as set out in the appended claims.

As illustrated in FIG. 2, a first embodiment of this invention provides a heat exchanger unit, including a first heat exchanger 1 and a second heat exchanger 2 that are in communication with each other. The first heat exchanger 1 includes a first housing 11 and a first heat exchanging tube bundle 12 and a second heat exchanging tube bundle 13 that are disposed in the first housing 11. The first housing 11 is provided with a first refrigerant inlet and a first refrigerant outlet. The second heat exchanging tube bundle 13 is disposed closer to the first refrigerant outlet than the first heat exchanging tube bundle 12. The second heat exchanger 2 includes a second housing 21 and a third heat exchanging tube bundle 22 and a fourth heat exchanging tube bundle 23 disposed in the second housing 21. The second housing 21 is provided with a second refrigerant inlet and a second refrigerant outlet. The fourth heat exchanging tube bundle 23 is disposed closer to the second refrigerant outlet than the third heat exchanging tube bundle 22. The first heat exchanging tube bundle 12 is in communication with the third heat exchanging tube bundle 22, and the second heat exchanging tube bundle 13 is in communication with the fourth heat exchanging tube bundle 23.
Specifically, a heat exchanging medium flowing in the first heat exchanging tube bundle 12, the second heat exchanging tube bundle 13, the third heat exchanging tube bundle 22, and the fourth heat exchanging tube bundle 23 is preferably water. Water is used as an example below. Of course, the heat exchanging medium is not limited to water, and other fluids that can exchange heat with the refrigerant are applicable to embodiments of the invention.
When each of the first heat exchanger 1 and the second heat exchanger 2 is a condenser, in the first heat exchanger 1, a high-temperature and high-pressure gaseous refrigerant enters from the first refrigerant inlet, and the heat of the high-temperature and high-pressure gaseous refrigerant in the first heat exchanger 1 is absorbed by the water in the first heat exchanging tube bundle 12 and the second heat exchanging tube bundle 13. During the heat exchange process, the high-temperature and high-pressure refrigerant is gradually condensed into high-pressure liquid and the temperature is gradually reduced, thus completing the condensation process. Since the second heat exchanging tube bundle 13 is closer to the first refrigerant outlet, the refrigerant enters from the first refrigerant inlet, sequentially exchanges heat with the first heat exchanging tube bundle 12 and the second heat exchanging tube bundle 13, and then is discharged from the first refrigerant outlet. Similarly, in the second heat exchanger 2, the high-temperature and high-pressure gaseous refrigerant enters from the second refrigerant inlet, sequentially exchanges heat with the third heat exchanging tube bundle 22 and the fourth heat exchanging tube bundle 23, and then is discharged from the second refrigerant outlet.
It should be noted that "refrigerant in" and "refrigerant out" indicated in FIG. 1 to FIG. 4 are for illustration only and represent "a refrigerant entering" and "a refrigerant flowing out", and do not represent actual positions of the first refrigerant inlet, the first refrigerant outlet, the second refrigerant inlet, and the second refrigerant outlet. Preferably, in directions illustrated in FIG. 1 to FIG. 4, in the first heat exchanger 1, the refrigerant enters from a top end of the first housing 11 and flows out from a bottom end of the first housing 11. In the second heat exchanger 2, the refrigerant enters from a top end of the second housing 21 and flows out from a bottom end of the second housing 21, where the top end and the bottom end may correspond to a top portion and a bottom portion in a radial direction of the housing.
Further, in the first heat exchanger 1, since the high-temperature and high-pressure refrigerant enters from the first refrigerant inlet and sequentially exchanges heat with the first heat exchanging tube bundle 12 and the second heat exchanging tube bundle 13, the heat exchanging medium in the first heat exchanging tube bundle 12 has a relatively high temperature after absorbing the heat of the high-temperature and high-pressure gaseous refrigerant, but after the high-temperature and high-pressure gaseous refrigerant exchanges heat with the first heat exchanging tube bundle 12, most or all of the gaseous refrigerant is condensed into liquid, and the condensed liquid refrigerant further exchanges heat with the second heat exchanging tube bundle 13, so that the part of the liquid refrigerant has a further reduced temperature after exchanging heat with the second heat exchanging tube bundle 13, and the heat exchanging medium in the second heat exchanging tube bundle 13 absorbs the heat of the refrigerant after flowing through the first heat exchanging tube bundle 12 and has a relatively low temperature (compared with a case in which the first heat exchanging tube bundle 12 directly exchanges heat with the high-temperature gaseous refrigerant). That is, when the configurations of the first heat exchanging tube bundle 12 and the second heat exchanging tube bundle 13 are substantially the same, the temperature rise of the heat exchanging medium in the first heat exchanging tube bundle 12 is higher than the temperature rise of the heat exchanging medium in the second heat exchanging tube bundle 13.
In the prior art, the first condenser 100 only includes one heat exchanging medium outlet. The heat exchanging medium after exchanging heat with the refrigerant in the first condenser 100 absorbs the heat released by the refrigerant in the first condenser 100, and then all enters the second condenser 200 to exchange heat with the refrigerant in the second condenser 200, resulting in a small temperature difference between the heat exchanging medium and the refrigerant in the second condenser 200, a small degree of supercooling at the condenser outlet of the second condenser 200, and a poor heat exchange effect. Compared with the technical solution in the prior art, embodiments of this invention utilize the fact that in the flow direction of the refrigerant, the second heat exchanging tube bundle 13 is close to the first refrigerant outlet, and the heat exchanging medium in the second heat exchanging tube bundle 13 has a lower outlet temperature than the heat exchanging medium in the first heat exchanging tube bundle 12, and communicate the second heat exchanging tube bundle 13 with the fourth heat exchanging tube bundle 23 of the second heat exchanger 2, so that the inlet temperature of the heat exchanging medium entering the fourth heat exchanging tube bundle 23 of the second heat exchanger 2 is reduced, the temperature difference between the heat exchanging medium in the fourth heat exchanging tube bundle 23 and the refrigerant in the second heat exchanger 2 is increased, the heat exchange effect is improved, and a greater degree of supercooling is ensured for the refrigerant at the outlet of the second heat exchanger 2, which is beneficial to improving the overall heating efficiency and heating capacity of the heat exchanger unit.
In addition, in some embodiments of this invention, the ratio of the flow capacity of the heat exchanging medium flowing through the second heat exchanging tube bundle 13 to the flow capacity of the heat exchanging medium flowing through the first heat exchanging tube bundle 12 is not particularly limited, and may be appropriately adjusted according to the capacity load and the like of the heat exchanger.
However, as a preferred solution, the flow capacity of the heat exchanging medium flowing through the second heat exchanging tube bundle 13 may be less than the flow capacity of the heat exchanging medium in the first heat exchanging tube bundle 12, and the flow capacity of the heat exchanging medium flowing through the third heat exchanging tube bundle 22 is greater than the flow capacity of the heat exchanging medium in the fourth heat exchanging tube bundle 23 (for example, the amount of water flowing through the first heat exchanging tube bundle 12 and the third heat exchanging tube bundle 22 is 90%, and the amount of water flowing through the second heat exchanging tube bundle 13 and the fourth heat exchanging tube bundle 23 is 10%).
Still referring to FIG. 2, in an embodiment of this invention, the first heat exchanger 1 further includes two first housing tube sheets 14, two first heat exchanger end covers 15, two first chambers 16, and at least one first separator 17. The two first housing tube sheets 14 are respectively disposed at two inner ends of the first housing 11 and are used for fixing the first heat exchanging tube bundle 12 and the second heat exchanging tube bundle 13. The two first heat exchanger end covers 15 are respectively disposed at two ends of the first housing 11, and the two first housing tube sheets 14 are respectively disposed corresponding to the two first heat exchanger end covers 15 and enclose two first chambers 16 with the first heat exchanger end covers 15. At least one first separator 17 is disposed in the first chambers 16 and divides the first chambers 16 into a first heat exchanging tube bundle chamber 161 in communication with the first heat exchanging tube bundle 12 and a second heat exchanging tube bundle chamber 162 in communication with the second heat exchanging tube bundle 13.
The second heat exchanger 2 further includes two second housing tube sheets 24, two second heat exchanger end covers 25, two second chambers 26, and at least one second separator 27. The two second housing tube sheets 24 are respectively disposed at two inner ends of the second housing 21 and are used for fixing the third heat exchanging tube bundle 22 and the fourth heat exchanging tube bundle 23. The two second heat exchanger end covers 25 are respectively disposed at two ends of the second housing 21, and the two second housing tube sheets 24 are respectively disposed corresponding to the two second heat exchanger end covers 25 and enclose two second chambers 26 with the second heat exchanger end covers 25. At least one second separator 27 is disposed in the second chambers 26 and divides the second chambers 26 into a first accommodating chamber 261 in communication with the third heat exchanging tube bundle 22 and a second accommodating chamber 262 in communication with the fourth heat exchanging tube bundle 23.
Specifically, as illustrated in FIG. 2, when the first heat exchanger 1 and the second heat exchanger 2 are connected in series, only one first separator 17 is disposed on the outlet side of the first heat exchanger 1, one second separator 27 is disposed on the inlet side of the second heat exchanger 2, the first heat exchanging tube bundle 12 is in communication with the third heat exchanging tube bundle 22, and the second heat exchanging tube bundle 13 is in communication with the fourth heat exchanging tube bundle 23.
In this way, only one outlet of the two first chambers 16 of the first heat exchanger 1 (the leaving water side of the first heat exchanger 1) and one inlet of the two second chambers 26 of the second heat exchanger 2 (the entering water side of the second heat exchanger 2) need to be changed slightly in structure, so that the temperature of part of the heat exchanging medium entering the second heat exchanger 2 is reduced, the overall heating capacity and heating efficiency of the heat exchanger unit is improved, and the cost is saved.
In the embodiment of this invention, in the above heat exchanger unit disposed in series, the first heat exchanging tube bundle 12, the second heat exchanging tube bundle 13, the third heat exchanging tube bundle 22, and the fourth heat exchanging tube bundle 23 are all single-pass heat exchanging tube bundles. The single-pass heat exchanging tube bundle has the advantage of large flow capacity. A person skilled in the art could select heat exchanging tube bundles of different passes according to actual needs, as long as the connection relationship between different heat exchanging tube bundles follows the above connection relationship, which is not limited in this embodiment.
Another embodiment of this invention provides an air conditioning system, including the above heat exchanger unit as a condenser. By using the above heat exchanger unit as a condenser, under the same working conditions (the same refrigerant temperature and pressure at the outlet of the compressor unit) of a compressor unit of the air conditioning system, the outlet temperature of the refrigerant in the second heat exchanger 2 can be reduced to a lower temperature, thereby ensuring a large degree of supercooling of the second heat exchanger 2, and improving the overall heating capacity and heating efficiency of the heat exchanger unit and the air conditioning system.
The above embodiment of this invention will be described by taking an example in which the entering water temperature of the first chamber 16 on the entering water side of the first heat exchanger 1 is 50°C and the leaving water temperature of the second chamber 26 on the leaving water side of the second heat exchanger 2 is 70°C.
Part of water entering the first chamber 16 at 50°C flows through the second heat exchanging tube bundle 13 to exchange heat with the refrigerant and then flows out of the second heat exchanging tube bundle chamber 162. At this time, for example, the leaving water temperature is 51.5°C, which is lower than the leaving water temperature 60°C of the first condenser 100 in the prior art illustrated in FIG. 1, that is, the temperature of the part of the entering water of the second heat exchanger 2 is significantly reduced. Further, the temperature of the refrigerant flowing out of the first heat exchanger 1 is 53°C, and the temperature of the refrigerant flowing out of the second heat exchanger 2 is 54.5°C, which is slightly higher than the temperature of the refrigerant flowing out of the first heat exchanger 1, but is still lower than the temperature (63°C) of the refrigerant at the outlet of the second condenser 200 in the prior art, that is, the temperature of the refrigerant at the outlet of the second heat exchanger 2 can be reduced and the degree of supercooling of the refrigerant at the outlet of the second heat exchanger 2 and the heating effect can be improved by introducing the water in the second heat exchanging tube bundle 13 into the fourth heat exchanging tube bundle 23 to exchange heat with the refrigerant in the second heat exchanger 2.
In some embodiments, the above air conditioning system may be a series counterflow chiller unit. It should be noted that other structures and connection relationships of the air conditioning system are not limited in embodiments of this invention, as long as they can form a complete refrigerant circulation loop.

As illustrated in FIG. 3, the second embodiment of this invention provides a heat exchanger unit, which differs from that in the first embodiment in the waterway connection between the first heat exchanger 1 and the second heat exchanger 2 and the structure of the first chamber 16 of the first heat exchanger 1 or the second chamber 26 of the second heat exchanger 2. Further, the first heat exchanger 1 further includes one fourth separator 18, which is disposed in the first chamber 16 on the entering water side of the first heat exchanger 1 and divides the first chamber 16 (the first chamber 16 on the right side in the drawing direction) into a third heat exchanging tube bundle chamber 163 and a fourth heat exchanging tube bundle chamber 164. Since the first separator 17 is disposed, the first chamber 16 on the left side of the drawing direction is divided into the first heat exchanging tube bundle chamber 161 and the second heat exchanging tube bundle chamber 162. The third heat exchanging tube bundle chamber 163 is in communication with the first heat exchanging tube bundle 12, and the fourth heat exchanging tube bundle chamber 164 is in communication with the first heat exchanging tube bundle 12 and the second heat exchanging tube bundle 13 at the same time. The first heat exchanging tube bundle 12 is a double-pass tube bundle, and includes a first tube body 121 and a second tube body 122 which are disposed in parallel and in communication with each other through the first heat exchanging tube bundle chamber 161. Two ends of the first tube body 121 are in communication with the first heat exchanging tube bundle chamber 161 and the third heat exchanging tube bundle chamber 163 respectively, and two ends of the second tube body 122 are in communication with the first heat exchanging tube bundle chamber 161 and the fourth heat exchanging tube bundle chamber 164 respectively. Two ends of the second heat exchanging tube bundle 13 are in communication with the second heat exchanging tube bundle chamber 162 and the fourth heat exchanging tube bundle chamber 164 respectively.
As illustrated in FIG. 3, the second heat exchanger 2 further includes two third separators 28 disposed in one of the second chambers 26 of the second heat exchanger 2. The two third separators 28 divide the second chamber 26 (the second chamber 26 on the right side of the drawing direction) into a third accommodating chamber 263 in communication with the third heat exchanging tube bundle 22, a fourth accommodating chamber 264 in communication with the fourth heat exchanging tube bundle 23, and a fifth accommodating chamber 265 between the third accommodating chamber 263 and the fourth accommodating chamber 264. The fifth accommodating chamber 265 is disposed corresponding to the third heat exchanging tube bundle 22. The third heat exchanging tube bundle 22 is a double-pass tube bundle, including a third tube body 221 and a fourth tube body 222 which are disposed in parallel and in communication with each other through the first accommodating chamber 261. Two ends of the third tube body 221 are in communication with the first accommodating chamber 261 and the third accommodating chamber 263 respectively, and two ends of the fourth tube body 222 are in communication with the first accommodating chamber 261 and the fifth accommodating chamber 265 respectively. Two ends of the fourth heat exchanging tube bundle 23 are in communication with the second accommodating chamber 262 and the fourth accommodating chamber 264 respectively.
In this embodiment, the waterway connection between the first heat exchanger 1 and the second heat exchanger 2 is that the fourth accommodating chamber 264 of the second heat exchanger 2 is in communication with the first heat exchanging tube bundle chamber 161 of the first heat exchanger 1 through an external pipeline. The first heat exchanging tube bundle chamber 161 is in communication with the third heat exchanging tube bundle chamber 163 through the first tube body 121, and then is in communication with the fifth accommodating chamber 265 of the second heat exchanger 2 through an external pipeline. The fifth accommodating chamber 265 is in communication with the third accommodating chamber 263 through the third heat exchanging tube bundle 22 and the first accommodating chamber 261.
In some preferred embodiments, the above separators disposed in the first chamber 16 may be collectively referred to as first separators 17, and the above separators disposed in the second chamber 26 may be collectively referred to as second separators 27. The chambers in communication with the first heat exchanging tube bundle 12 may be collectively referred to as first heat exchanging tube bundle chambers 161, and the chambers in communication with the second heat exchanging tube bundle may be collectively referred to as second heat exchanging tube bundle chambers 162. The chambers in communication with the third heat exchanging tube bundle 22 may be collectively referred to as first accommodating chambers 261, and the chambers in communication with the fourth heat exchanging tube bundle 24 may be collectively referred to as second accommodating chambers 262. From the perspective of easy reading and understanding, the above first separators 17, the second separators 27, the heat exchanging tube bundle chambers, and the accommodating chambers are renamed according to different positions thereof (mainly, the chamber on the inlet side (the entering water side) of the first heat exchanger 1 is named, and the accommodating chamber on the outlet side (the leaving water side) of the second heat exchanger 2 is named).
The structures of the first heat exchanger 1 and the second heat exchanger 2 are described in detail above, and the flow directions of the waterways thereof are described below.
In this embodiment, water as the heat exchanging medium enters the first heat exchanging tube bundle 12 and the second heat exchanging tube bundle 13 from the fourth heat exchanging tube bundle chamber 164 of the first heat exchanger 1.
The water entering the second heat exchanging tube bundle 13 enters the second accommodating chamber 262 of the second heat exchanger 2 through the second heat exchanging tube bundle chamber 162, exchanges heat in the fourth heat exchanging tube bundle 23, flows out through the fourth accommodating chamber 264 and enters the first heat exchanging tube bundle chamber 161 of the first heat exchanger 1, mixes with the water flowing through the second tube body 122, flows through the first tube body 121 and flows out through the third heat exchanging tube bundle chamber 163, enters the fifth accommodating chamber 265 of the second heat exchanger 2 through an external pipeline, flows through the fourth tube body 222, the first accommodating chamber 261, and the third tube body 221, and finally is discharged from the third accommodating chamber 263, thus completing heat exchange and flowing out of the second heat exchanger 2.
As described above, the first heat exchanging tube bundle 12 is a double-pass tube bundle including the first tube body 121 and the second tube body 122. The water entering the second tube body 122 of the first heat exchanging tube bundle 12 merges with the water from the fourth accommodating chamber 264 after entering the first heat exchanging tube bundle chamber 161, which will not be repeated here.
In this embodiment, after the entering water of the heat exchanger unit enters the heat exchanger unit from the fourth heat exchanging tube bundle chamber 164 of the first heat exchanger 1, part of the entering water firstly flows through the second heat exchanging tube bundle 13 of the first heat exchanger 1 and then flows through the fourth heat exchanging tube bundle 23 of the second heat exchanger 2, exchanges heat with the refrigerant that has been partially cooled and condensed in the first heat exchanger 1 and the second heat exchanger 2 respectively, enters the first heat exchanging tube bundle chamber 161 of the first heat exchanger 1 through an external pipeline, and exchanges heat with the high-temperature and high-pressure refrigerant entering the first heat exchanger 1 from the outlet of the compressor to further increase its temperature. The water entering the first heat exchanging tube bundle chamber 161 from the fourth heat exchanging tube bundle 23 can cool the refrigerant in the first heat exchanger 1, so that the refrigerant maintains an appropriate temperature difference with the water from the second heat exchanger 2, thereby ensuring the heating effect of the first heat exchanger 1.
In this embodiment, for example, as a housing-and-tube heat exchanger, there is no need to make a large structural change to the first heat exchanger 1 and the second heat exchanger 2, and only corresponding separators need to be disposed at ends of a respective housing and proper external pipelines need to be configured, thereby simplifying waterway arrangement of the heat exchanger unit. In some embodiments, on the premise of ensuring that the flow directions of the waterways are unchanged or the positions of the inlets and the outlets of the waterways are unchanged, the number of waterway passes of the first heat exchanging tube bundle 12 and the third heat exchanging tube bundle 22 may also be adjusted and corresponding separators may be added, which is not limited in embodiments of this invention.
Preferably, the external pipeline through which the fourth accommodating chamber 264 is in communication with the first heat exchanging tube bundle chamber 161 is provided with a first water pump 31. The first water pump 31 can pump the heat exchanging medium in the fourth accommodating chamber 264 to the first heat exchanging tube bundle chamber 161, thereby overcoming the flow resistance caused by this part of water passing through the second heat exchanging tube bundle 13, the fourth heat exchanging tube bundle 23, and the external pipeline, and is beneficial to achieve pressure balance and full mix with the water from the second tube body 122 in the first heat exchanging tube bundle chamber 161 to ensure the water flow capacity requirement of the first tube body 121.
Corresponding to the second embodiment of this invention, there is further provided an air conditioning system, including the heat exchanger unit according to the second embodiment. By adopting the above heat exchanger unit, the water flowing through the first heat exchanger 1 and the second heat exchanger 2 exchanges heat with the high-temperature and high-pressure refrigerants respectively entering the first heat exchanger 1 and the second heat exchanger 2. In the waterway pass, the water as the heat exchanging medium and the refrigerant are always kept at an appropriate temperature difference, thereby achieving sufficient heat exchange, so that the refrigerant at the outlet of the second heat exchanger 2 is reduced to a lower temperature, a large degree of supercooling of the refrigerant is ensured, and the overall heating capacity and heating efficiency of the heat exchanger unit and the air conditioning system are improved.
The heat exchange between water and refrigerant in each heat exchanger is described by way of an example in which the entering water temperature of the fourth heat exchanging tube bundle chamber 164 is 50°C as the entering water of the heat exchanger unit, and the leaving water temperature of the third accommodating chamber 263 is 70°C as the leaving water of the heat exchanger unit.
In the entering water entering the heat exchanger unit, part of the entering water exchanges heat with the refrigerant through the second heat exchanging tube bundle 13 and then flows out of the second heat exchanging tube bundle chamber 162. At this time, the leaving water temperature is 51.5°C, which is lower than the overall leaving water temperature 60°C of the first condenser 100 in the prior art, that is, the entering water temperature of the second heat exchanger 2 is significantly reduced. Further, the temperature of the refrigerant flowing out of the first heat exchanger 1 is 53°C, which is substantially the same as the temperature (53°C) of the refrigerant flowing out of the first condenser 100 in the prior art, that is, the structure of the heat exchanger unit in the second embodiment of this invention basically does not cause large fluctuation to the temperature of the refrigerant of the first heat exchanger 1, thereby ensuring the operation reliability and heating effect of the heat exchanger unit. Still further, the temperature of the refrigerant flowing out of the second heat exchanger 2 in some embodiments of this invention is 54.5°C, which is slightly higher than the temperature of the refrigerant flowing out of the first heat exchanger 1, but is still lower than the temperature (63°C) of the refrigerant at the outlet of the second heat exchanger 2 in the prior art, that is, the temperature of the refrigerant in the second heat exchanger 2 can be reduced and the degree of supercooling of the refrigerant and the heating effect can be improved by introducing the water with a lower temperature in the second heat exchanging tube bundle 13 into the fourth heat exchanging tube bundle 23 to exchange heat with the refrigerant in the second heat exchanger 2.
On the other hand, part of the entering water passes through the second tube body 122 of the first heat exchanging tube bundle 12 and exchanges heat with the refrigerant entering the first heat exchanger 1 and preliminarily subjected to heat exchange with the water of the first tube body 121 to increase its temperature, and then mixes with the above water from the fourth heat exchanging tube bundle 23 of the second heat exchanger 2 in the first heat exchanging tube bundle chamber 161, and continues to flow through the first tube body 121 and the third tube body 221 and the fourth tube body 222 of the second heat exchanger 2 to continue to exchange heat with the high-temperature and high-pressure refrigerant to increase its temperature.
As described above, in each waterway pass of the first heat exchanger 1 and the second heat exchanger 2, the water as the heat exchanging medium and the refrigerant are always kept at an appropriate temperature difference, thereby achieving sufficient heat exchange, so that the refrigerant at the outlet of the second heat exchanger 2 is reduced to a lower temperature, a large degree of supercooling of the refrigerant is ensured, and the overall heating capacity and heating efficiency of the heat exchanger unit and the air conditioning system are improved.

As illustrated in FIG. 4, the third embodiment of this invention provides a heat exchanger unit, which has substantially the same structure as the heat exchanger unit of the second embodiment, except that the second heat exchanging tube bundle chamber 162 is in communication with the fourth accommodating chamber 264 through an external pipeline, the fourth heat exchanging tube bundle 23 is in communication with the first heat exchanger bundle chamber 161 through the second accommodating chamber 262 and through an external pipeline, the first heat exchanging tube bundle chamber 161 is in communication with the fifth accommodating chamber 265 through the first tube body 121 and through an external pipeline, and the fifth accommodating chamber 265 is in communication with the third accommodating chamber 263 through the third heat exchanging tube bundle 22.
That is, in this embodiment, the waterway flows sequentially through the fourth heat exchanging tube bundle chamber 164, the second heat exchanging tube bundle 13, the second heat exchanging tube bundle chamber 162, the fourth accommodating chamber 264, the fourth heat exchanging tube bundle 23, the second accommodating chamber 262, the first heat exchanging tube bundle chamber 161, the first tube body, the third heat exchanging tube bundle chamber 163, the fifth accommodating chamber 265, the fourth tube body 222, the first accommodating chamber 261, the third tube body 221, and the third accommodating chamber 263.
In this way, a person skilled in the art could adjust the connection position between the second heat exchanging tube bundle chamber 162 and the fourth heat exchanging tube bundle 23 of the second heat exchanger 2 according to actual conditions, and the flexibility is strong.
Further, the pipeline through which the fourth heat exchanging tube bundle 23 is in communication with the first heat exchanging tube bundle chamber 161 is provided with a second water pump 32. The second water pump 32 can pump the heat exchanging medium in the second accommodating chamber 262 to the first heat exchanging tube bundle chamber 161, thereby overcoming the flow resistance caused by this part of water passing through the second heat exchanging tube bundle 13, the fourth heat exchanging tube bundle 23, and the external pipeline, and achieves pressure balance and full mix with the water from the second tube body 122 in the first heat exchanging tube bundle chamber 161 to ensure the water flow capacity requirement of the first tube body 121. It is beneficial to improve the heat exchange efficiency between the heat exchanging medium and the refrigerant.
Corresponding to the third embodiment of this invention, there is further provided an air conditioning system, including the heat exchanger unit according to the third embodiment. By adopting the above heat exchanger unit, the water flowing through the first heat exchanger 1 and the second heat exchanger 2 exchanges heat with the high-temperature and high-pressure refrigerants respectively entering the first heat exchanger 1 and the second heat exchanger 2. In the waterway pass, the water as the heat exchanging medium and the refrigerant are always kept at an appropriate temperature difference, thereby achieving sufficient heat exchange, so that the refrigerant at the outlet of the second heat exchanger 2 is reduced to a lower temperature, and the overall heating capacity and heating efficiency of the heat exchanger unit and the air conditioning system are improved.
For example, the entering water temperature of the fourth heat exchanging tube bundle chamber 164 is 50°C, and the leaving water temperature of the third accommodating chamber 263 is 70°C
In the entering water of the heat exchanger unit, part of the entering water exchanges heat with the refrigerant through the second heat exchanging tube bundle 13 and then flows out of the second heat exchanging tube bundle chamber 162. The leaving water temperature thereof is 51.5°C, which is lower than the leaving water temperature 60°C of the first condenser 100 in the prior art, that is, the entering water temperature of the second heat exchanger 2 is partially reduced. Further, the temperature of the refrigerant flowing out of the first heat exchanger 1 is 53°C, which is substantially the same as the temperature (53°C) of the refrigerant flowing out of the first heat exchanger 1 in the prior art, that is, the structure of the heat exchanger unit in the third embodiment of this invention basically does not cause large fluctuation to the temperature of the refrigerant at the outlet of the first heat exchanger 1, thereby ensuring the operation reliability and heating effect of the heat exchanger unit. Still further, the temperature of the refrigerant flowing out of the second heat exchanger 2 in some embodiments of this invention is 54.5°C, which is slightly higher than the temperature of the refrigerant flowing out of the first heat exchanger 1, but is still lower than the temperature (63°C) of the refrigerant at the outlet of the second condenser 200 in the prior art, that is, the temperature of the refrigerant in the second heat exchanger 2 can be reduced and the degree of supercooling of the refrigerant at the outlet of the second heat exchanger 2 and the heating effect can be improved by introducing the water in the second heat exchanging tube bundle 13 into the fourth heat exchanging tube bundle 23 to exchange heat with the refrigerant in the second heat exchanger 2.
On the other hand, the flow and heat exchange of part of the entering water after passing through the second tube body 122 of the first heat exchanging tube bundle 12 are the same as those in the third embodiment, which will not be repeated here.

As illustrated in FIG. 5, this embodiment provides a heat exchanger unit including the first heat exchanger 1 and the second heat exchanger 2, which is similar in structure to that of the first embodiment, but differs in the following points.
The first heat exchanger 1 further includes

a fourth separator 18 disposed in the first chamber 16 and dividing the first chamber 16 into a third heat exchanging tube bundle chamber 163 and a fourth heat exchanging tube bundle chamber 164, and
a fifth separator 19 dividing the first heat exchanging tube bundle chamber 161 into a chamber 161A and a chamber 161B, the chamber 161A being located above the chamber 161B.

The first heat exchanging tube bundle 12 is a three-pass heat exchanging tube bundle and includes a first tube body, a second tube body, and a third tube body which are disposed in parallel (the first tube body, the second tube body, and the third tube body are respectively disposed from top to bottom, and the vertical direction refers to the radial direction of the first housing 11). Two ends of the first tube body are respectively in communication with the chamber 161A and the third heat exchanging tube bundle chamber 163, two ends of the second tube body are respectively in communication with the chamber 161B and the third heat exchanging tube bundle chamber 163, and two ends of the third tube body are respectively in communication with the chamber 161B and the fourth heat exchanging tube bundle chamber 164.
The second heat exchanger 2 further includes

two third separators 28 disposed in the second chamber 26 and dividing the second chamber 26 into a third accommodating chamber 263 in communication with the third heat exchanging tube bundle 22, a fifth accommodating chamber 265, and a fourth accommodating chamber 264 in communication with the fourth heat exchanging tube bundle 23, and
a sixth separator 29 disposed in the second chamber 26 and dividing the first accommodating chamber 261 into an accommodating chamber 261A and an accommodating chamber 261B, the accommodating chamber 261A being adjacent to the accommodating chamber 261B.

The third heat exchanging tube bundle 22 is a three-pass heat exchanging tube bundle and includes a fourth tube body, a fifth tube body, and a sixth tube body which are disposed in parallel (the fourth tube body, the fifth tube body, and the sixth tube body are respectively disposed from top to bottom, and the vertical direction refers to the radial direction of the second housing 21). Two ends of the fourth tube body are respectively in communication with the third accommodating chamber 263 and the accommodating chamber 261A, two ends of the fifth tube body are respectively in communication with the fifth accommodating chamber 265 and the accommodating chamber 261B, and two ends of the sixth tube body are respectively in communication with the fifth accommodating chamber 265 and the accommodating chamber 261B.
The pipeline connection between the first heat exchanger 1 and the second heat exchanger 2 is that the second heat exchanging tube bundle chamber 162 is in communication with the second accommodating chamber 262 through an external pipeline, the fourth accommodating chamber 264 is in communication with the chamber 161B through an external pipeline, and the chamber 161A is in communication with the accommodating chamber 261B through an external pipeline.
The communication structures of the first heat exchanger 1 and the second heat exchanger 2 in this embodiment are specifically described above, and the flow directions of the waterways thereof are described below.
As the entering water of the heat exchanger unit, the entering water enters from the fourth heat exchanging tube bundle chamber 164, partially flows into the first heat exchanging tube bundle 12, and partially flows into the second heat exchanging tube bundle 13.
The water entering the first heat exchanging tube bundle 12 flows into the chamber 161B through the third tube body, then enters the chamber 261B through the second tube body, the third heat exchanging tube bundle chamber 163, the first tube body, and the chamber 161A, and then is discharged along the sixth tube body, the fifth accommodating chamber 265, the fifth tube body, the chamber 261A, the fourth tube body, and the third accommodating chamber 263.
The water entering the second heat exchanging tube bundle 13 enters the chamber 161B through the second heat exchanging tube bundle chamber 162, the second accommodating chamber 262, the fourth heat exchanging tube bundle 23, and the fourth accommodating chamber 264, and merges with the water entering the chamber 161B through the third tube body, and the flow pass after entering the chamber 161B is repeated, which will not be repeated here.
It should be noted that, in this embodiment, although it is illustrated that the first heat exchanging tube bundle 12 and the third heat exchanging tube bundle 22 are three-pass tube bundles, it can be foreseen that a person skilled in the art could adjust the number of waterways of the first heat exchanging tube bundle 12 and the third heat exchanging tube bundle 22, the number of separators in each heat exchanger, and the relative positions of the separators and the heat exchanging tube bundles according to actual needs, so that the water in the first heat exchanging tube bundle 12 has a corresponding inlet and outlet, the water in the third heat exchanging tube bundle 22 has a corresponding inlet and outlet, and the water in the second heat exchanging tube bundle 13 in the first heat exchanger 1 can return to the first heat exchanging tube bundle 12 and the third heat exchanging tube bundle 22 for heat exchange after entering the fourth tube bundle 23 in the second heat exchanger 2, thereby improving the cooling effect on the refrigerant.
In addition, although four different embodiments are illustrated, a person skilled in the art could combine the solutions described in the different embodiments, which will not be repeated in this specification.
Corresponding to the fourth embodiment of this invention, there is further provided an air conditioning system, including the heat exchanger unit according to the fourth embodiment. By adopting the above heat exchanger unit, the water flowing through the first heat exchanger 1 and the second heat exchanger 2 exchanges heat with the high-temperature and high-pressure refrigerants respectively entering the first heat exchanger 1 and the second heat exchanger 2. In the waterway pass, the water as the heat exchanging medium and the refrigerant are always kept at an appropriate temperature difference, thereby achieving sufficient heat exchange, so that the refrigerant at the outlet of the second heat exchanger 2 is reduced to a lower temperature, and the overall heating capacity and heating efficiency of the heat exchanger unit and the air conditioning system are improved. In this embodiment, the refrigerant at the outlet of the second heat exchanger 2 can also be cooled to 54.5°C, which is the same as the above first, second, and third embodiments described above and will not be repeated here.

As illustrated in FIG. 6, the fifth embodiment of this invention provides a heat exchanger unit, which has substantially the same structure as the first embodiment, except that the second heat exchanger 2 includes two second separators 27, the two second separators 27 are respectively disposed in two second chambers 26 at two ends of the second housing 21, and divide each of the second chambers 26 into a first accommodating chamber 261 in communication with the third heat exchanging tube bundle 22 and a second accommodating chamber 262 in communication with the fourth heat exchanging tube bundle 23, and an outlet of the fourth heat exchanging tube bundle 23 is in communication with an inlet of the third heat exchanging tube bundle 22 through a pipeline, specifically, the second accommodating chamber 262 on the outlet side of the fourth heat exchanging tube bundle 23 is in communication with the first accommodating chamber 261 on the inlet side of the third heat exchanging tube bundle 22 through a pipeline.
In this way, the heat exchanging medium at the outlet of the fourth heat exchanging tube bundle 23 can enter the third heat exchanging tube bundle 22 to continue to exchange heat with the refrigerant in the second housing 21, thereby improving the heat exchange efficiency and the degree of supercooling of the refrigerant at the outlet of the second heat exchanger 2. Further, the pipeline through which the outlet of the fourth heat exchanging tube bundle 23 is in communication with the inlet of the third heat exchanging tube bundle 22 is provided with a third water pump 33. Other structures and principles of the fifth embodiment are the same as those of the first embodiment, which will not be repeated in this specification.
The operation of the fifth embodiment of this invention will be described below by taking an example in which the entering water temperature of the first chamber 16 on the entering water side of the first heat exchanger 1 is 50°C and the leaving water temperature of the second chamber 26 on the leaving water side of the second heat exchanger 2 is 70°C.
The heat exchange process of the water entering the first chamber 16 passing through the first heat exchanging tube bundle 12 and the third heat exchanging tube bundle 22 is similar to that in the prior art, which will not be repeated in this specification.
Part of water entering the first chamber 16 at 50°C flows through the second heat exchanging tube bundle 13 to exchange heat with the refrigerant and then flows out of the second heat exchanging tube bundle chamber 162. At this time, for example, the leaving water temperature is 51.5°C, which is lower than the leaving water temperature 60°C of the first condenser 100 in the prior art illustrated in FIG. 1, that is, the temperature of the part of the entering water of the second heat exchanger 2 is significantly reduced. Further, the temperature of the refrigerant flowing out of the first heat exchanger 1 is 53°C, and the temperature of the refrigerant flowing out of the second heat exchanger 2 is 54.5°C, which is slightly higher than the temperature of the refrigerant flowing out of the first heat exchanger 1, but is still lower than the temperature (63°C) of the refrigerant at the outlet of the second condenser 200 in the prior art, that is, the temperature of the refrigerant at the outlet of the second heat exchanger 2 can be reduced and the degree of supercooling of the refrigerant at the outlet of the second heat exchanger 2 and the heating effect can be improved by introducing the water in the second heat exchanging tube bundle 13 into the fourth heat exchanging tube bundle 23 to exchange heat with the refrigerant in the second heat exchanger 2 and then introducing the water at the outlet of the fourth heat exchanging tube bundle 23 into the third heat exchanging tube bundle 22 to exchange heat with the refrigerant in the second housing 21.

As illustrated in FIG. 7, the sixth embodiment of this invention provides a heat exchanger unit, including the first heat exchanger 1, the second heat exchanger 2, a third heat exchanger 6, and a fourth heat exchanger 7.
The first heat exchanger 1 includes a first housing 11, a first refrigerant flow passage 111, and a first heat exchanging tube bundle 12. The first housing 11 is provided with a first refrigerant inlet and a first refrigerant outlet. The first refrigerant flow passage 111 is formed between the first refrigerant inlet and the first refrigerant outlet (a space other than the first heat exchanging tube bundle 12 in the first housing 11). The first heat exchanging tube bundle 12 is disposed in the first housing 11.
The second heat exchanger 2 includes a second housing 21, a second refrigerant flow passage 211, and a third heat exchanging tube bundle 22. The second housing 21 is provided with a second refrigerant inlet and a second refrigerant outlet. The second refrigerant flow passage 211 is formed between the second refrigerant inlet and the second refrigerant outlet (a space other than the third heat exchanging tube bundle 22 in the second housing 21). The third heat exchanging tube bundle 22 is disposed in the second housing 21. An inlet of the third heat exchanging tube bundle 22 is in communication with an outlet of the first heat exchanging tube bundle 12.
The third heat exchanger 6 is disposed outside the first housing 11. The third heat exchanger 6 includes a third refrigerant flow passage 61 and a first heat exchanging flow passage 62 disposed corresponding to the third refrigerant flow passage 61. The third refrigerant flow passage 61 is in communication with the first refrigerant flow passage 111 (an inlet of the third refrigerant flow passage 61 is in communication with the first refrigerant outlet). An inlet of the first heat exchanging flow passage 62 is in communication with an inlet of the first heat exchanging tube bundle 12 and is in communication with a water supply end (not illustrated in the figure).
The fourth heat exchanger 7 is disposed outside the second housing 21. The fourth heat exchanger 7 includes a fourth refrigerant flow passage 71 and a second heat exchanging flow passage 72 disposed corresponding to the fourth refrigerant flow passage 71. The fourth refrigerant flow passage 71 is in communication with the second refrigerant flow passage 211 (an inlet of the fourth refrigerant flow passage 71 is in communication with the second refrigerant outlet). An inlet of the second heat exchanging flow passage 72 is in communication with an outlet of the first heat exchanging flow passage 62.
In this embodiment, a heat exchanging medium flowing in the first heat exchanging tube bundle 12, the third heat exchanging tube bundle 22, the first heat exchanging flow passage 62, and the second heat exchanging flow passage 72 is preferably water. The working process of the heat exchanger unit will be described below by taking water as an example. Of course, the heat exchanging medium is not limited to water, and other fluids that can exchange heat with the refrigerant are applicable to embodiments of this invention. The third heat exchanger 6 and the fourth heat exchanger 7 may be plate heat exchangers or other heat exchangers.
Flow process of a refrigerant: When each of the first heat exchanger 1 and the second heat exchanger 2 is a condenser, a first path of high-temperature and high-pressure gaseous refrigerant sequentially flows through the first refrigerant inlet, the first refrigerant flow passage 111, the first refrigerant outlet, and the third refrigerant flow passage 61 for heat exchange, and then is condensed into a liquid refrigerant and discharged. A second path of high-temperature and high-pressure gaseous refrigerant sequentially flows through the second refrigerant inlet, the second refrigerant flow passage 211, the second refrigerant outlet, and the fourth refrigerant flow passage 71 for heat exchange, and then is condensed into a liquid refrigerant and discharged.
Flow process of the heat exchanging medium: Water as the heat exchanging medium is divided into two flow paths respectively entering the first heat exchanging flow passage 62 and the first heat exchanging tube bundle 12.
The water entering the first heat exchanging tube bundle 12 exchanges heat with the refrigerant in the first housing 11, then enters the third heat exchanging tube bundle 22 and exchanges heat with the refrigerant in the second housing 21, and then is discharged.
The water entering the first heat exchanging flow passage 62 of the third heat exchanger 6 exchanges heat with the refrigerant entering the third refrigerant flow passage 61, and then enters the second heat exchanging flow passage 72 of the fourth heat exchanger 7 and exchanges heat with the refrigerant in the fourth refrigerant flow passage 71.
In this embodiment, since the refrigerant at the outlet of the first heat exchanger 1 further exchanges heat with the heat exchanging medium in the third heat exchanger 6, the outlet temperature of the refrigerant is further reduced. Since the refrigerant at the outlet of the second heat exchanger 2 further exchanges heat with the heat exchanging medium having a relatively low temperature from the second heat exchanging flow passage 72 in the fourth heat exchanger 7, the outlet temperature of the refrigerant in the heat exchanger unit is also reduced.
Specifically, since the high-temperature and high-pressure refrigerant enters from the first refrigerant inlet and sequentially exchanges heat with the first heat exchanging tube bundle 12 and the first heat exchanging flow passage 62, the heat exchanging medium in the first heat exchanging tube bundle 12 has a relatively high temperature after absorbing the heat of the high-temperature and high-pressure gaseous refrigerant, but after the high-temperature and high-pressure gaseous refrigerant exchanges heat with the first heat exchanging tube bundle 12, most or all of the gaseous refrigerant is condensed into liquid, and the condensed liquid refrigerant further exchanges heat with the water flowing in the first heat exchanging flow passage 62, so that the part of the liquid refrigerant has a further reduced temperature after exchanging heat with the first heat exchanging flow passage 62, and the heat exchanging medium in the first heat exchanging flow passage 62 absorbs the heat of the refrigerant after flowing through the first heat exchanging tube bundle 12 and has a still relatively low temperature (compared with a case in which the first heat exchanging tube bundle 12 directly exchanges heat with the high-temperature gaseous refrigerant). That is, when the configurations of the first heat exchanging tube bundle 12 and the first heat exchanging flow passage 62 are substantially the same, the temperature rise of the heat exchanging medium in the first heat exchanging tube bundle 12 is higher than the temperature rise of the heat exchanging medium in the first heat exchanging flow passage 62. Similarly, when the configurations of the third heat exchanging tube bundle 22 and the second heat exchanging flow passage 72 are substantially the same, the temperature rise of the heat exchanging medium in the third heat exchanging tube bundle 22 is higher than the temperature rise of the heat exchanging medium in the second heat exchanging flow passage 72.
In the prior art, after heat exchange between the heat exchanging medium and the refrigerant in the first condenser 100, all the heat exchanging medium enters the second heat exchanger 200 and exchanges heat with the refrigerant in the second condenser 200, resulting in a small temperature difference between the heat exchanging medium and the refrigerant in the second condenser 200, a small degree of supercooling of the refrigerant at the outlet of the second condenser 200, and a poor heat exchange effect.
Compared with the prior art, embodiments of this invention utilize the fact that in the flow direction of the refrigerant, the heat exchanging medium in the downstream first heat exchanging flow passage 62 has a lower temperature than the heat exchanging medium in the upstream first heat exchanging tube bundle 12, and the heat exchanging medium in the downstream second heat exchanging flow passage 72 has a lower temperature than the heat exchanging medium in the upstream third heat exchanging tube bundle 22, communicate the first heat exchanging flow passage 62 with the second heat exchanging flow passage 72 of the fourth heat exchanger 7, and communicate the inlet of the first heat exchanging flow passage 62 of the third heat exchanger 6 with the water supply end, so that the inlet temperature of the heat exchanging medium in the first heat exchanging flow passage 62 of the third heat exchanger 6 and the second heat exchanging flow passage 72 of the fourth heat exchanger 7 is reduced, the temperature difference between the heat exchanging medium in the first heat exchanging flow passage 62 and the corresponding refrigerant and the temperature difference between the second heat exchanging flow passage 72 and the corresponding refrigerant are increased, the heat exchange effect is improved, the temperature of the refrigerant at the outlet of the third heat exchanger 6 is lower than the temperature of the refrigerant at the outlet of the first heat exchanger 1, the temperature of the refrigerant at the outlet of the fourth heat exchanger 7 is lower than the temperature of the refrigerant at the outlet of the second heat exchanger 2, and the refrigerant at the final outlet of the heat exchanger unit has a greater degree of supercooling, which is beneficial to improving the overall heating efficiency and heating capacity of the heat exchanger unit.
It should be noted that "refrigerant in" and "refrigerant out" indicated in FIG. 1 to FIG. 7 are for illustration only and represent "a refrigerant entering" and "a refrigerant flowing out", and do not represent actual positions of the first refrigerant inlet, the first refrigerant outlet, the second refrigerant inlet, and the second refrigerant outlet. Preferably, in directions illustrated in FIG. 1 to FIG. 7, in the first heat exchanger 1, the refrigerant enters from a top end of the first housing 11 and flows out from a bottom end of the first housing 11. In the second heat exchanger 2, the refrigerant enters from a top end of the second housing 21 and flows out from a bottom end of the second housing 21, where the top end and the bottom end may correspond to a top portion and a bottom portion in a radial direction of the housing.
In embodiments of this invention, the ratio of the flow capacity of the heat exchanging medium flowing through the first heat exchanging flow passage 62 to the flow capacity of the heat exchanging medium flowing through the first heat exchanging tube bundle 12 is not particularly limited, and may be appropriately adjusted according to the capacity load and the like of the heat exchanger.
However, as a preferred solution, the flow capacity of the heat exchanging medium flowing through the first heat exchanging flow passage 62 may be less than the flow capacity of the heat exchanging medium in the first heat exchanging tube bundle 12, and the flow capacity of the heat exchanging medium flowing through the third heat exchanging tube bundle 22 is greater than the flow capacity of the heat exchanging medium in the second heat exchanging flow passage 72 (for example, the amount of water flowing through the first heat exchanging tube bundle 12 and the third heat exchanging tube bundle 22 is 90%, and the amount of water flowing through the first heat exchanging flow passage 62 and the second heat exchanging flow passage 72 is 10%).
As a preferred example in the embodiment of this invention, in the above heat exchanger unit disposed in series, the first heat exchanging tube bundle 12, the first heat exchanging flow passage 62, the third heat exchanging tube bundle 22, and the second heat exchanging flow passage 72 may all be single-pass heat exchanging tube bundles. The single-pass heat exchanging tube bundle has the advantage of large flow capacity. A person skilled in the art could select heat exchanging tube bundles of different passes according to actual needs, as long as the connection relationship between different heat exchanging tube bundles follows the above connection relationship, which is not limited in this embodiment.
Preferably, a pipeline through which the first heat exchanging flow passage 62 is in communication with the second heat exchanging flow passage 72 is provided with a fourth water pump 34. The fourth water pump 34 can pump the heat exchanging medium in the first heat exchanging flow passage 62 to the second heat exchanging flow passage 72, thereby overcoming the flow resistance of the heat exchanging medium and improving the heat exchange efficiency.
Preferably, an outlet of the second heat exchanging flow passage 72 is in communication with an inlet of the third heat exchanging tube bundle 22 through a pipeline. Therefore, the heat exchanging medium at the outlet of the second heat exchanging flow passage 72 can enter the third heat exchanging tube bundle 22 to continue to exchange heat with the refrigerant in the second refrigerant flow passage 211, thereby improving the heat exchange efficiency and the degree of supercooling of the refrigerant at the outlet of the second heat exchanger 2. Further, the pipeline through which the outlet of the second heat exchanging flow passage 72 is in communication with the inlet of the third heat exchanging tube bundle 22 is provided with a fifth water pump (not illustrated in the figure). The fifth water pump can pump the heat exchanging medium in the second heat exchanging flow passage 72 to the third heat exchanging tube bundle 22, thereby overcoming the flow resistance of the heat exchanging medium and improving the heat exchange efficiency.
Another embodiment of this invention provides an air conditioning system, including the above heat exchanger unit as a condenser. By using the above heat exchanger unit as a condenser, under the same working conditions (the same refrigerant temperature and pressure at the outlet of the compressor unit) of a compressor unit of the air conditioning system, the outlet temperature of the refrigerant in the heat exchanger unit can be reduced to a lower temperature, thereby improving the overall heating capacity and heating efficiency of the heat exchanger unit and the air conditioning system.
The operation process of the above embodiment of this invention will be described below by taking an example in which the entering water temperature at the entering water side of the first heat exchanger 1 and the third heat exchanger 6 are 50°C and the leaving water temperature at the leaving water side of the second heat exchanger 2 is 70°C.
The leaving water temperature of the heat exchanging medium in the first heat exchanging tube bundle 12 after exchanging heat with the refrigerant in the first refrigerant flow passage 111 is 60°C, and the leaving water temperature of the heat exchanging medium at 60°C after entering the second heat exchanger 2 and exchanging heat is 70°C.
After the refrigerant at the outlet of the first heat exchanger 1 enters the third refrigerant flow passage 61 of the third heat exchanger 6 and exchanges heat with the heat exchanging medium in the first heat exchanging flow passage 62, the outlet temperature of the refrigerant is 53°C.
After the refrigerant at the outlet of the second heat exchanger 2 enters the fourth refrigerant flow passage 71 of the fourth heat exchanger 7 and exchanges heat with the heat exchanging medium in the second heat exchanging flow passage 72, the outlet temperature of the refrigerant is 56°C. The above outlet temperature is lower than the temperature (63°C) of the refrigerant at the outlet of the second condenser 200 in the prior art illustrated in FIG. 1, that is, the temperature of the refrigerant at the final outlet of the heat exchanger unit can be reduced and the degree of supercooling of the refrigerant at the final outlet and the heating effect of the heat exchanger unit can be improved by introducing the water with a relatively low temperature in the first heat exchanging flow passage 62 into the second heat exchanging flow passage 72 to exchange heat with the refrigerant in the second heat exchanger 2.
In some embodiments, the above air conditioning system may be a series counterflow chiller unit. It should be noted that other structures and connection relationships of the air conditioning system are not limited in embodiments of this invention, as long as they can form a complete refrigerant circulation loop.
It should be noted that "first", "second", "third", "fourth", and the like in this specification may be used herein to describe various components, but these components should not be limited by these terms. These terms are only used to distinguish one component from another. For example, a first component may be designated as a second component, and likewise, a second component may be designated as a first component.
The above embodiments are merely embodiments of this invention and are not intended to limit this invention. Various modifications, equivalent substitutions, and improvements may be made within the protection scope of this invention as set out in the appended claims.

Claims

A heat exchanger unit, comprising:
a first heat exchanger (1) including a first housing (11) provided with a first refrigerant inlet and a first refrigerant outlet, a first refrigerant flow passage (111) formed between the first refrigerant inlet and the first refrigerant outlet, and a first heat exchanging tube bundle (12) disposed in the first housing;

a second heat exchanger (2) including a second housing (21) provided with a second refrigerant inlet and a second refrigerant outlet, a second refrigerant flow passage (211) formed between the second refrigerant inlet and the second refrigerant outlet, and a third heat exchanging tube bundle (22) disposed in the second housing and having an inlet in communication with an outlet of the first heat exchanging tube bundle;

a third heat exchanger (6) including a third refrigerant flow passage (61) in communication with the first refrigerant flow passage, and a first heat exchanging flow passage (62) disposed corresponding to the third refrigerant flow passage; and

a fourth heat exchanger (7) including a fourth refrigerant flow passage (71) in communication with the second refrigerant flow passage, and a second heat exchanging flow passage (72) disposed corresponding to the fourth refrigerant flow passage and having an inlet in communication with an outlet of the first heat exchanging flow passage.
The heat exchanger unit according to claim 1, wherein
the third heat exchanger (6) is disposed in the first housing (11), the first heat exchanging flow passage (62) is a second heat exchanging tube bundle (13) disposed in the first housing, the second heat exchanging tube bundle is disposed closer to the first refrigerant outlet than the first heat exchanging tube bundle (12), and the third refrigerant flow passage (61) and the first refrigerant flow passage (111) together form an empty space inside the first housing, and

the fourth heat exchanger (7) is disposed in the second housing (21), the second heat exchanging flow passage (72) is a fourth heat exchanging tube bundle (23) disposed in the second housing, the fourth heat exchanging tube bundle is disposed closer to the second refrigerant outlet than the third heat exchanging tube bundle (22), and the fourth refrigerant flow passage (71) and the second refrigerant flow passage (211) together form an empty space inside the second housing.
The heat exchanger unit according to claim 2, wherein
the first heat (1) exchanger further includes

first housing tube sheets (14) respectively disposed at two inner ends of the first housing (11) and fixing the first heat exchanging tube bundle (12) and the second heat exchanging tube bundle (13),

first heat exchanger end covers (15) respectively disposed at two ends of the first housing,

first chambers (16) enclosed by the first heat exchanger end covers and the first housing tube sheets disposed corresponding to the first heat exchanger end covers, and

at least one first separator (17) disposed in the first chamber and dividing the first chamber into a first heat exchanging tube bundle chamber (161) in communication with the first heat exchanging tube bundle and a second heat exchanging tube bundle chamber (162) in communication with the second heat exchanging tube bundle.
The heat exchanger unit according to claim 3, wherein
the second heat exchanger (2) further includes

second housing tube sheets (24) respectively disposed at two inner ends of the second housing (21) and fixing the third heat exchanging tube bundle (22) and the fourth heat exchanging tube bundle (23),

second heat exchanger end covers (25) respectively disposed at two ends of the second housing,

second chambers (26) enclosed by the second heat exchanger end covers and the second housing tube sheets disposed corresponding to the second heat exchanger end covers, and

at least one second separator (27) disposed in the second chamber and dividing the second chamber into a first accommodating chamber (261) in communication with the third heat exchanging tube bundle and a second accommodating chamber (262) in communication with the fourth heat exchanging tube bundle.
The heat exchanger unit according to claim 4, wherein
the second heat exchanger (2) further includes

two third separators (28) disposed in the second chamber (26) and dividing the second chamber into a third accommodating chamber (263) in communication with the third heat exchanging tube bundle (22), a fourth accommodating chamber (264) in communication with the fourth heat exchanging tube bundle (23), and a fifth accommodating chamber (265) between the third accommodating chamber and the fourth accommodating chamber.
The heat exchanger unit according to claim 5, wherein
the fourth accommodating chamber (264) is in communication with the first heat exchanging tube bundle chamber (161) through a pipeline,

the first heat exchanging tube bundle chamber is in communication with the fifth accommodating chamber (265) through a pipeline, and

the fifth accommodating chamber is in communication with the third accommodating chamber (263) through the third heat exchanging tube bundle.
The heat exchanger unit according to claim 6, wherein
the pipeline through which the fourth accommodating chamber (264) is in communication with the first heat exchanging tube bundle (161) chamber is provided with a first water pump (31).
The heat exchanger unit according to any of claims 5 to 7, wherein
the second heat exchanging tube bundle chamber (162) is in communication with the fifth accommodating chamber (265) through a pipeline,

the fourth heat exchanging tube bundle (23) is in communication with the first heat exchanging tube bundle chamber (161) through a pipeline,

the first heat exchanging tube bundle chamber is in communication with the fifth accommodating chamber through a pipeline, and

the fifth accommodating chamber is in communication with the third accommodating chamber (263) through the third heat exchanging tube bundle (22).
The heat exchanger unit according to claim 8, wherein
the pipeline through which the fourth heat exchanging tube bundle (23) is in communication with the first heat exchanging tube bundle chamber (161) is provided with a second water pump (32).
The heat exchanger unit according to any of claims 2 to 10, wherein
an outlet of the fourth heat exchanging tube bundle (23) is in communication with the inlet of the third heat exchanging tube bundle (22) through a pipeline,

optionally, wherein

the pipeline through which the outlet of the fourth heat exchanging tube bundle is in communication with the inlet of the third heat exchanging tube bundle is provided with a third water pump (33).
The heat exchanger unit according to any one of claims 1 to 10, wherein
each of the first heat exchanger (1) and the second heat exchanger (2) is a condenser.
The heat exchanger unit according to any of claims 1 to 11, wherein
the third heat exchanger (6) is disposed outside the first housing (11), and an inlet of the third refrigerant flow passage (61) is in communication with the first refrigerant outlet, and

the fourth heat exchanger (7) is disposed outside the second housing (21), and an inlet of the fourth refrigerant flow passage (71) is in communication with the second refrigerant outlet.
The heat exchanger unit according to claim 12, wherein
a pipeline through which the first heat exchanging flow passage (62) is in communication with the second heat exchanging flow passage (72) is provided with a fourth water pump (34).
The heat exchanger unit according to claim 12, wherein
an outlet of the second heat exchanging flow passage (72) is in communication with the inlet of the third heat exchanging tube bundle (22) through a pipeline,

optionally, wherein

the pipeline through which the outlet of the second heat exchanging flow passage is in communication with the inlet of the third heat exchanging tube bundle is provided with a fifth water pump.
An air conditioning system, comprising:
the heat exchanger unit according to any one of claims 1 to 14 as a condenser.