Air conditioning system

Abstract

The utility model relates to the technical field of air conditioners, in particular to an air conditioning system. The two-stage compression heat pump system aims at solving the problems that when an existing two-stage compression heat pump system adopting an intercooler conducts refrigeration, the refrigerating capacity is reduced, and the energy efficiency is low. In order to achieve the purpose, the air conditioning system comprises a low-pressure compressor, an intercooler, a high-pressure compressor, a first heat exchanger, a second heat exchanger, a third heat exchanger, a first throttling device, an ejector, a gas-liquid separator and the like, and a first coil pipe is arranged in the intercooler. The first coil pipe can be used for providing cooling capacity to cool exhaust gas of the low-pressure compressor, so that under the condition that two-stage compression intermediate cooling is guaranteed, the problems that the refrigerating capacity in a system is reduced and the performance of the system is poor due to the fact that the cooling capacity is provided through a refrigerant obtained through exhaust throttling and pressure reduction of the high-pressure compressor in a refrigeration mode are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of air conditioning, in particular to an air conditioning system. Background Art

[0002] In a heat pump system, when the required compressor pressure is relatively large or the exhaust temperature is high, in order to ensure the reliability of the compressor operation and the operating performance of the system, a two-stage compression and an intercooler are usually used in combination to control the exhaust temperature of the compressor. That is, the exhaust of the low-pressure compressor enters the intercooler and is cooled by the throttled low-temperature refrigerant discharged from the condenser before being input into the high-pressure compressor.

[0003] In the prior art, the exhaust gas of the high-pressure compressor passes through the condenser and the expansion valve in turn to throttle and reduce the pressure before entering the intercooler to provide cooling capacity. Part of the refrigerant absorbs heat in the intercooler and evaporates into gas and merges into the cooled low-pressure exhaust gas to enter the high-pressure compressor again for circulation. This cooling method can play a role in replenishing air and increasing enthalpy under heating conditions, but under cooling conditions, it will lead to a reduction in liquid refrigerant entering the evaporator, resulting in a reduction in cooling capacity and reduced system energy efficiency.

[0004] Accordingly, the art needs a new technical solution to solve the above problems. Utility Model Content

[0005] In order to solve at least one of the above problems in the prior art, that is, to solve the problem of reduced cooling capacity and low energy efficiency in the existing two-stage compression heat pump system using an intercooler during refrigeration, the present application provides an air conditioning system, which includes:

[0006] Low pressure compressor;

[0007] an intercooler, wherein a first inlet of the intercooler is in communication with an exhaust port of the low-pressure compressor, and a first coil is disposed in the intercooler;

[0008] a high-pressure compressor, wherein an air intake port of the high-pressure compressor is in communication with a first outlet of the intercooler;

[0009] a first heat exchanger, wherein a first port of the first heat exchanger is in communication with an exhaust port of the high-pressure compressor;

[0010] an ejector, wherein an air inlet of the ejector is in communication with a second port of the first heat exchanger;

[0011] a second heat exchanger, wherein a first port of the second heat exchanger is in communication with an exhaust port of the ejector;

[0012] A third heat exchanger, wherein a first port of the third heat exchanger is connected to an injection port of the ejector;

[0013] a first throttling device, wherein a first port of the first throttling device is in communication with a second port of the third heat exchanger;

[0014] A gas-liquid separator, wherein the air inlet, the exhaust port and the liquid discharge port of the gas-liquid separator are respectively connected to the second port of the second heat exchanger, the air intake port of the low-pressure compressor and the second port of the first throttling device.

[0015] When the above technical solution is adopted, the first coil arranged in the intercooler can be used to provide cooling capacity for cooling the exhaust gas of the low-pressure compressor, thereby avoiding the problem of reduced cooling capacity and poor system performance in the system caused by providing cooling capacity through the refrigerant throttled and reduced in pressure by the exhaust gas of the high-pressure compressor in the refrigeration mode while ensuring two-stage compression intercooling.

[0016] In the preferred technical solution of the above-mentioned air-conditioning system, the air-conditioning system also includes a regenerator, and the first inlet, the first outlet, the second inlet and the second outlet of the regenerator are respectively connected to the second port of the first heat exchanger, the air inlet of the ejector, the exhaust port of the gas-liquid separator and the intake port of the low-pressure compressor.

[0017] In the preferred technical solution of the air conditioning system, the intercooler is further provided with a second inlet and a second outlet.

[0018] The second port of the first heat exchanger is in communication with the second inlet of the intercooler,

[0019] The second outlet of the intercooler is communicated with the air inlet of the ejector.

[0020] In the preferred technical solution of the above air-conditioning system, the air-conditioning system also includes a second throttling device, a first port of the second throttling device is connected to the second port of the first heat exchanger, and a second port of the second throttling device is connected to the second inlet of the intercooler.

[0021] In the preferred technical solution of the above-mentioned air-conditioning system, the intercooler is also provided with a third inlet and a second coil, the second port of the first heat exchanger is respectively connected to the second inlet and the third inlet of the intercooler, the third inlet of the intercooler is connected to the input end of the second coil, and the output end of the second coil is connected to the second outlet of the intercooler.

[0022] When the above technical solution is adopted, cooling capacity can be provided by the first coil and the refrigerant that has been throttled and depressurized at the same time, further ensuring the cooling effect of the exhaust gas of the low-pressure compressor, and the refrigerant after the first heat exchanger can be supercooled, thereby improving the energy efficiency of the system.

[0023] In the preferred technical solution of the above-mentioned air-conditioning system, the air-conditioning system also includes a regenerator, and the first inlet, the first outlet, the second inlet and the second outlet of the regenerator are respectively connected to the second outlet of the intercooler, the air inlet of the ejector, the exhaust port of the gas-liquid separator and the air intake port of the low-pressure compressor.

[0024] In the preferred technical solution of the air-conditioning system, both ends of the first coil are connected to the low-grade heat ends.

[0025] When the above technical solution is adopted, the waste heat of the intercooler can be reused while ensuring sufficient cooling of the exhaust gas of the low-pressure compressor.

[0026] In the preferred technical solution of the above air-conditioning system, the first heat exchanger is a liquid-cooled heat exchanger.

[0027] In the preferred technical solution of the air conditioning system, the liquid cooling inlet and the liquid cooling outlet of the liquid cooling heat exchanger are respectively connected to the high-grade hot end; or

[0028] One end of the first coil is connected to the return water of the high-grade hot end, and the other end is connected to the liquid cooling inlet of the liquid cooling heat exchanger, and the liquid cooling outlet of the liquid cooling heat exchanger is connected to the water outlet of the high-grade hot end; or

[0029] The first coil exchanges heat with the return water pipe of the high-grade hot end.

[0030] When the above technical solution is adopted, the waste heat of the first heat exchanger can be reused, and when the return water of the first heat exchanger is preheated by the heat absorbed by the first coil, the condensing temperature of the first heat exchanger can be reduced, further improving the energy efficiency of the system.

[0031] In the preferred technical solution of the air-conditioning system, the refrigerant used in the air-conditioning system is CO2.

[0032] When the above technical solution is adopted, using CO2 as a refrigerant will not cause harm to the environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The air conditioning system of the present application is described below with reference to the accompanying drawings. In the accompanying drawings:

[0034] Figure 1 A schematic diagram of an air conditioning system according to an embodiment of the present application;

[0035] Figure 2 This is a schematic diagram of an air conditioning system according to another embodiment of the present application.

[0036] Reference numerals list

[0037] 11. Low-pressure compressor; 12. High-pressure compressor; 20. Intercooler; 31. First heat exchanger; 32. Second heat exchanger; 33. Third heat exchanger; 40. Regenerator; 411. First inlet; 412. First outlet; 421. Second inlet; 422. Second outlet; 50. Ejector; 61. First throttling device; 62. Second throttling device; 70. Gas-liquid separator; 80. High-grade hot end; 90. Low-grade hot end. DETAILED DESCRIPTION

[0038] The preferred embodiments of the present application are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present application and are not intended to limit the scope of protection of the present application. For example, although the air-conditioning system in this embodiment is introduced in conjunction with the cooling mode, this is not intended to limit the scope of protection of the present application. Without departing from the principles of the present application, those skilled in the art may apply the present application to other application scenarios such as heating or a combination of cooling and heating.

[0039] It should be noted that, in the description of the present application, the terms "upper", "lower", "left", "right", "inside", "outside" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, which are merely for the convenience of description and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance. In addition, in the description of the present application, "multiple" refers to at least two.

[0040] In addition, it should be noted that in the description of this application, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0041] As described in the background technology, in a heat pump system, when the required compressor pressure is relatively large or the exhaust temperature is relatively high, in order to ensure the reliability of the compressor operation and the operating performance of the system, it is usually chosen to use a combination of two-stage compression and an intercooler to control the exhaust temperature of the compressor. That is, the exhaust gas of the low-pressure compressor enters the intercooler and is heat-exchanged and cooled with the throttled low-temperature refrigerant discharged from the condenser before being input into the high-pressure compressor.

[0042] In the prior art, the exhaust gas of the high-pressure compressor passes through the condenser and the expansion valve in turn to throttle and reduce the pressure before entering the intercooler to provide cooling capacity. Part of the refrigerant absorbs heat in the intercooler and evaporates into gas and merges into the cooled low-pressure exhaust gas to enter the high-pressure compressor again for circulation. This cooling method can play a role in replenishing air and increasing enthalpy under heating conditions, but under cooling conditions, it will lead to a reduction in liquid refrigerant entering the evaporator, resulting in a reduction in cooling capacity and reduced system energy efficiency.

[0043] In order to solve the problems of reduced cooling capacity and low energy efficiency in the existing two-stage compression heat pump system using an intercooler during refrigeration, the present application provides an air-conditioning system, which includes: a low-pressure compressor; an intercooler, a first inlet of the intercooler is connected to the exhaust port of the low-pressure compressor, and a first coil is arranged in the intercooler; a high-pressure compressor, an air intake port of the high-pressure compressor is connected to the first outlet of the intercooler; a first heat exchanger, a first port of the first heat exchanger is connected to the exhaust port of the high-pressure compressor; an ejector, an air intake port of the ejector is connected to the second port of the first heat exchanger; a second heat exchanger, a first port of the second heat exchanger is connected to the exhaust port of the ejector; a third heat exchanger, a first port of the third heat exchanger is connected to the injection port of the ejector; a first throttling device, a first port of the first throttling device is connected to the second port of the third heat exchanger; a gas-liquid separator, an air intake port, an exhaust port and a liquid discharge port of the gas-liquid separator are respectively connected to the second port of the second heat exchanger, the air intake port of the low-pressure compressor and the second port of the first throttling device.

[0044] When the above technical solution is adopted, the first coil arranged in the intercooler can be used to provide cooling capacity for cooling the exhaust gas of the low-pressure compressor, thereby avoiding the problem of reduced cooling capacity and poor system performance in the system caused by providing cooling capacity through the refrigerant throttled and reduced in pressure by the exhaust gas of the high-pressure compressor in the refrigeration mode while ensuring two-stage compression intercooling.

[0045] Refer to the following Figure 1 and Figure 2 , the air conditioning system of the present application is described. Among them, Figure 1 A schematic diagram of an air conditioning system according to an embodiment of the present application; Figure 2 This is a schematic diagram of an air conditioning system according to another embodiment of the present application.

[0046] like Figure 1As shown, in a preferred embodiment, the air conditioning system includes a low-pressure compressor 11, a high-pressure compressor 12, an intercooler 20, a first heat exchanger 31, a second heat exchanger 32, a third heat exchanger 33, a regenerator 40, an ejector 50, a first throttling device 61, and a gas-liquid separator 70. The first inlet of the intercooler 20 is connected to the exhaust port of the low-pressure compressor 11, the air intake of the high-pressure compressor 12 is connected to the first outlet of the intercooler 20, the first port of the first heat exchanger 31 (the right port in the direction of the figure) is connected to the exhaust port of the high-pressure compressor 12, and the first inlet 411, the first outlet 412, the second inlet 421, and the second outlet 422 of the regenerator 40 are respectively connected to the second port (the left port in the direction of the figure) of the first heat exchanger 31, the air intake of the ejector 50, the exhaust port of the gas-liquid separator 70, and the air intake of the low-pressure compressor 11. The exhaust port of the ejector 50 is connected to the first port of the second heat exchanger 32 (the left port in the direction shown in the figure), the first port of the third heat exchanger 33 (the left port in the direction shown in the figure) is connected to the injection port of the ejector 50, the first port of the first throttling device 61 is connected to the second port of the third heat exchanger 33 (the right port in the direction shown in the figure), the air inlet, exhaust port and drain port of the gas-liquid separator 70 are respectively connected to the second port of the second heat exchanger 32 (the right port in the direction shown in the figure), the second inlet 421 of the regenerator 40 and the second port of the first throttling device 61.

[0047] Among them, a first coil (not shown in the figure) is arranged in the intercooler 20, and the first heat exchanger 31 is arranged as a liquid-cooled heat exchanger. Both ends of the first coil are connected to the low-grade hot end 90, and the liquid-cooled inlet and liquid-cooled outlet of the liquid-cooled heat exchanger are respectively connected to the high-grade hot end 80. When the above technical solution is adopted, the cooling effect of the exhaust gas of the low-pressure compressor 11 is guaranteed, and the waste heat of the intercooler 20 and the first heat exchanger 31 is reused.

[0048] In this embodiment, the refrigerant is first compressed into a high-temperature and high-pressure gas by the low-pressure compressor 11, the gaseous refrigerant enters the intercooler 20 to be cooled, and then enters the high-pressure compressor 12 to be compressed again, the gaseous refrigerant discharged from the high-pressure compressor 12 is cooled by the first heat exchanger 31 to become a refrigerant gas at room temperature and high pressure, and then passes through the first inlet 411 and the first outlet 412 of the regenerator 40 to be supercooled and enter the ejector 50 as a power fluid, and at the same time, the ejector 50 inhales the refrigerant gas generated by the heat exchange of the third heat exchanger 33, and the gas-liquid two-phase cooling After the refrigerant is mixed, it is ejected to the second heat exchanger 32 through the ejector 50. The refrigerant absorbs heat and vaporizes in the second heat exchanger 32. Since the heat exchange of the refrigerant may be insufficient, the mixed refrigerant enters the gas-liquid separator 70. The separated gaseous refrigerant passes through the second inlet 421 and the second outlet 422 of the regenerator 40 and is overheated and returns to the low-pressure compressor 11. The separated liquid refrigerant enters the third heat exchanger 33 after throttling and reducing the pressure through the first throttling device 61 to continue heat exchange. The refrigerant after heat exchange is sucked into the ejector 50, thereby performing a reciprocating cycle of refrigeration.

[0049] like Figure 2 As shown, in another preferred embodiment, the air-conditioning system further includes a second throttling device 62, and the intercooler 20 is also provided with a second inlet, a third inlet, a second outlet and a second coil (not shown in the figure), wherein the downstream pipeline of the second port of the first heat exchanger 31 is divided into two paths, one path is connected to the second inlet of the intercooler 20 through the second throttling device 62, and the other path is connected to the third inlet of the intercooler 20, the third inlet of the intercooler 20 is connected to the input end of the second coil, the output end of the second coil is connected to the second outlet of the intercooler 20, and the second outlet of the intercooler 20 is connected to the first inlet 411 of the regenerator 40.

[0050] In this embodiment, the refrigerant flows in the direction Figure 1 The process is basically the same, but the refrigerant at the second port of the first heat exchanger 31 is divided into two paths, the first path enters the intercooler 20 through the second throttling device 62, and the second path directly enters the second coil for supercooling. At this time, the first path refrigerant throttled and depressurized by the second throttling device 62 and the first coil provide cooling capacity for the intercooler 20 at the same time, and part of the refrigerant in the first path evaporates after absorbing heat and merges into the cooled refrigerant discharged from the low-pressure compressor 11, and then directly enters the high-pressure compressor 12; the second path refrigerant enters the regenerator 40 through the second outlet of the intercooler 20. However, since the first coil and the first path refrigerant provide cooling capacity for the intercooler 20 at the same time, under the condition of ensuring the exhaust cooling of the low-pressure compressor 11, compared with the method of providing cooling capacity only by the refrigerant after throttling and depressurization, this embodiment can reduce the amount of refrigerant evaporated in the first path refrigerant, thereby reducing the amount of refrigerant required to enter the first path to ensure the cooling capacity in the refrigeration system.

[0051] It should be explained that although the air-conditioning system in the present application is introduced in conjunction with the cooling mode, this is not intended to limit the scope of protection of the present application, and those skilled in the art can modify it as needed, as long as it does not hinder the functional realization of the present application. In an alternative embodiment, the present application can also achieve heating, and the first heat exchanger 31 can be placed indoors. In another alternative embodiment, those skilled in the art can also add pipelines and valve bodies to control the flow direction of the refrigerant so that it can achieve switching between heating and cooling.

[0052] It will be understood by those skilled in the art that, although the intercooler 20 and the first heat exchanger 31 in the present application are independently used for waste heat recovery, their configuration is not static. In an alternative embodiment, one end of the first coil can be connected to the return water of the high-grade hot end, and the other end can be connected to the liquid cooling inlet of the first heat exchanger 31, and the liquid cooling outlet of the first heat exchanger 31 can be connected to the outlet water of the high-grade hot end. At this time, the cooling of the refrigerant in the first heat exchanger 31 and the recovery of waste heat are completed by water flow. In another alternative embodiment, the heat recovered by the first coil can also be preheated by heat exchange with the return water pipe of the high-grade hot end. In addition, in a possible embodiment, the high-grade hot end 80 can be domestic water at about 70°C, and the low-grade hot end 90 can be floor heating water at about 35°C. Of course, the settings of the high-grade hot end 80 and the low-grade hot end 90 are not fixed. In an alternative embodiment, the heat obtained by the intercooler 20 or the first coil may not be recovered, and a cooling box may be set to dissipate heat. In another alternative embodiment, the high-grade hot end 80 or the low-grade hot end 90 may not be set as domestic water, and heat storage may be performed through other heat exchange media and devices. In addition, the settings of the second throttling device 62 and the second coil are not necessary. In an alternative embodiment, the refrigerant at the second port of the first heat exchanger 31 can be supercooled only through the second coil. In another alternative embodiment, the refrigerant at the second port of the first heat exchanger 31 is supercooled only through the second inlet of the intercooler 20, and then enters the regenerator 40 through the second outlet of the intercooler 20.

[0053] Those skilled in the art may also understand that the regenerator 40 may be omitted, in which case the second port of the first heat exchanger 31 or the second outlet of the intercooler 20 may be directly connected to the air inlet of the ejector 50, and the exhaust port of the gas-liquid separator 70 may be connected to the air intake of the compressor 11. In addition, the first heat exchanger 31 may not be configured as a liquid-cooled heat exchanger, and those skilled in the art may select different types of first heat exchangers 31 as required, as long as direct or indirect heat exchange can be completed. In addition, in the present embodiment, the refrigerant used in the air-conditioning system is CO2. As a new generation of clean refrigerant, CO2 is non-toxic and harmless, has good environmental performance, and has outstanding heating performance, but its setting is not fixed, and those skilled in the art may replace other refrigerants as required.

[0054] Those skilled in the art will appreciate that, although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present application and form different embodiments. For example, in the claims of the present application, any one of the claimed embodiments may be used in any combination.

[0055] So far, the technical solutions of the present application have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present application is obviously not limited to these specific embodiments. Without departing from the principles of the present application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present application.

Claims

1. An air conditioning system, characterized in that: include: Low pressure compressor; an intercooler, wherein a first inlet of the intercooler is communicated with an exhaust port of the low-pressure compressor, and a first coil is disposed in the intercooler; a high-pressure compressor, wherein an air intake port of the high-pressure compressor is in communication with a first outlet of the intercooler; a first heat exchanger, wherein a first port of the first heat exchanger is in communication with an exhaust port of the high-pressure compressor; an ejector, wherein an air inlet of the ejector is in communication with a second port of the first heat exchanger; a second heat exchanger, wherein a first port of the second heat exchanger is in communication with an exhaust port of the ejector; A third heat exchanger, wherein a first port of the third heat exchanger is connected to an injection port of the ejector; a first throttling device, wherein a first port of the first throttling device is in communication with a second port of the third heat exchanger; A gas-liquid separator, wherein the air inlet, the exhaust port and the liquid discharge port of the gas-liquid separator are respectively connected to the second port of the second heat exchanger, the air intake port of the low-pressure compressor and the second port of the first throttling device.

2. The air conditioning system according to claim 1, characterized in that: The air conditioning system also includes a regenerator, a first inlet, a first outlet, a second inlet, and a second outlet of the regenerator are respectively connected to the second port of the first heat exchanger, the air inlet of the ejector, the exhaust port of the gas-liquid separator, and the air intake port of the low-pressure compressor.

3. The air conditioning system according to claim 1, characterized in that: The intercooler is also provided with a second inlet and a second outlet. The second port of the first heat exchanger is in communication with the second inlet of the intercooler, The second outlet of the intercooler is communicated with the air inlet of the ejector.

4. The air conditioning system according to claim 3, characterized in that: The air conditioning system further includes a second throttling device, a first port of the second throttling device is in communication with a second port of the first heat exchanger, and a second port of the second throttling device is in communication with a second inlet of the intercooler.

5. The air conditioning system according to claim 4, characterized in that: The intercooler is also provided with a third inlet and a second coil. The second port of the first heat exchanger is respectively connected to the second inlet and the third inlet of the intercooler. The third inlet of the intercooler is connected to the input end of the second coil. The output end of the second coil is connected to the second outlet of the intercooler.

6. The air conditioning system according to claim 3, characterized in that: The air conditioning system also includes a regenerator, a first inlet, a first outlet, a second inlet, and a second outlet of the regenerator are respectively connected to the second outlet of the intercooler, the air inlet of the ejector, the exhaust port of the gas-liquid separator, and the air intake port of the low-pressure compressor.

7. The air conditioning system according to claim 1, characterized in that: Both ends of the first coil are connected to the low-grade hot ends.

8. The air conditioning system according to claim 1, characterized in that: The first heat exchanger is a liquid-cooled heat exchanger.

9. The air conditioning system according to claim 8, characterized in that: The liquid cooling inlet and the liquid cooling outlet of the liquid cooling heat exchanger are respectively connected to the high-grade hot end; or One end of the first coil is connected to the return water of the high-grade hot end, and the other end is connected to the liquid cooling inlet of the liquid cooling heat exchanger, and the liquid cooling outlet of the liquid cooling heat exchanger is connected to the water outlet of the high-grade hot end; or The first coil exchanges heat with the return water pipe of the high-grade hot end.

10. The air conditioning system according to claim 1, characterized in that: The refrigerant used in the air conditioning system is CO2.

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