Heat pump system

Abstract

The utility model discloses a heat pump system. The heat pump system comprises a refrigerant circulation loop, a first air supplementing pipeline and a second air supplementing pipeline. The refrigerant circulation loop comprises an evaporator, a first compressor, a second compressor, a condenser and a flash evaporation assembly which are sequentially arranged. An air suction port of the first compressor is connected with the evaporator, and an exhaust port is connected with an air suction port of the second compressor. And an exhaust port of the second compressor is connected with an air inlet of the condenser. The flash assembly has an inlet, a liquid outlet, a first gas outlet, and a second gas outlet. A liquid outlet of the flash evaporation assembly is connected with the evaporator. The first end of the first gas supplementing pipeline is connected with the first gas outlet. The second end is connected with an air supply port of the first compressor. The first end of the second gas supplementing pipeline is connected with the second gas outlet. And the second end is connected with a pipeline between the first compressor and the second compressor. And by arranging the two air supplementing pipelines, the utilization rate of the refrigerant is increased, the refrigerant circulation efficiency is improved, and then the operation energy efficiency of the heat pump system is improved.

Description

Technical Field

[0001] The present application relates to a refrigeration and heating system, and in particular to a heat pump system. Background Art

[0002] Heat pump units have the advantages of being clean, environmentally friendly, energy-saving and efficient. In recent years, they have been more and more widely used in large-scale central heating systems. In existing heat pump units, the circulation efficiency of the refrigerant is low, resulting in low operating energy efficiency of the heat pump unit. Therefore, how to improve the circulation efficiency of the refrigerant is the key to improving the performance of the heat pump unit.

[0003] It should be noted that the statements in this background technology section only provide background technology related to the present application and do not necessarily constitute prior art. Utility Model Content

[0004] The present application provides a heat pump system to improve the circulation efficiency of refrigerant.

[0005] The present application provides a heat pump system, including a refrigerant circulation loop, a first air supply pipeline and a second air supply pipeline. The refrigerant circulation loop includes an evaporator, a first compressor, a second compressor, a condenser and a flash assembly arranged in sequence on the flow path of the refrigerant. The air intake of the first compressor is connected to the evaporator. The exhaust port of the first compressor is connected to the air intake of the second compressor. The first compressor also has an air supply port. The exhaust port of the second compressor is connected to the air inlet of the condenser. The flash assembly is connected to the condenser to perform two-stage flashing of the liquid refrigerant discharged from the condenser. The flash assembly has an inlet connected to the condenser, a liquid outlet for discharging the liquid refrigerant, a first gas outlet for discharging the gaseous refrigerant and a second gas outlet for discharging the gaseous refrigerant. The pressure of the gaseous refrigerant discharged from the first gas outlet is less than the pressure of the gaseous refrigerant discharged from the second gas outlet. The liquid outlet of the flash assembly is connected to the evaporator. The first end of the first air supply pipeline is connected to the first gas outlet, and the second end of the first air supply pipeline is connected to the air supply port. The first end of the second air supply pipeline is connected to the second gas outlet, and the second end of the second air supply pipeline is connected to the pipeline between the first compressor and the second compressor.

[0006] In some embodiments, the flash assembly includes a first flash chamber, a second flash chamber, and a throttling assembly. The first flash chamber and the second flash chamber are connected in series. The throttling assembly is arranged between the first flash chamber and the second flash chamber. The inlet is arranged on the first flash chamber. The liquid outlet and the first gas outlet are both arranged on the second flash chamber. The second gas outlet is arranged on the first flash chamber. After the refrigerant flashes through the first flash chamber, the gaseous part is discharged through the second gas outlet, and the liquid part enters the second flash chamber through the throttling assembly and flashes in the second flash chamber. The gaseous refrigerant after flashing is discharged through the first gas outlet, and the liquid refrigerant is discharged through the liquid outlet.

[0007] In some embodiments, the throttling assembly includes a connecting pipeline and a first throttling valve. The first flash chamber and the second flash chamber are connected in series through the connecting pipeline. The first throttling valve is arranged on the connecting pipeline.

[0008] In some embodiments, the throttling assembly includes a partition and a throttling hole. The partition is configured to separate the internal space of the flash assembly into two areas to form a first flash chamber and a second flash chamber. The throttling hole is arranged on the partition.

[0009] In some embodiments, a first control valve is further included. The first control valve is disposed on the first air supply pipeline to control the flow rate of the refrigerant in the first air supply pipeline.

[0010] In some embodiments, a second control valve is further included. The second control valve is disposed on the second air supply pipeline to control the flow rate of the refrigerant in the second air supply pipeline.

[0011] In some embodiments, the first compressor comprises a two-stage centrifugal compressor, and the air supply port leads to between two impellers of the two-stage centrifugal compressor.

[0012] In some embodiments, the liquid bypass pipeline and a second throttle valve disposed on the liquid bypass pipeline are further included. The liquid bypass pipeline is connected between the evaporator and the condenser. When the flow rate of the refrigerant required by the evaporator is greater than the flow rate of the refrigerant circulating back to the evaporator from the liquid outlet, the liquid bypass pipeline is configured to be in a connected state so that a portion of the liquid refrigerant in the condenser flows to the evaporator after passing through the liquid bypass pipeline and the second throttle valve.

[0013] In some embodiments, the opening degree of the second throttle valve is adjustable.

[0014] In some embodiments, a gas bypass pipeline is further included. The gas bypass pipeline is connected between the evaporator and the condenser. The gas bypass pipeline can be set to be on and off, so that when the gas bypass pipeline is connected, a part of the refrigerant entering the condenser from the second compressor directly flows back to the evaporator through the gas bypass pipeline to reduce the amount of refrigerant participating in the heat cycle in the heat pump system.

[0015] In some embodiments, a third control valve is further included. The third control valve is arranged on the gas bypass pipeline, and the opening degree of the third control valve is adjustable.

[0016] Based on the technical solution provided by the present application, the heat pump system includes a refrigerant circulation loop, a first air supply pipeline and a second air supply pipeline. The refrigerant circulation loop includes an evaporator, a first compressor, a second compressor, a condenser and a flash assembly arranged in sequence on the flow path of the refrigerant. The air intake of the first compressor is connected to the evaporator. The exhaust port of the first compressor is connected to the air intake of the second compressor. The first compressor also has an air supply port. The exhaust port of the second compressor is connected to the air inlet of the condenser. The flash assembly is connected to the condenser to perform two-stage flashing of the liquid refrigerant discharged from the condenser. The flash assembly has an inlet connected to the condenser, a liquid outlet for discharging the liquid refrigerant, a first gas outlet for discharging the gaseous refrigerant and a second gas outlet for discharging the gaseous refrigerant. The pressure of the gaseous refrigerant discharged from the first gas outlet is less than the pressure of the gaseous refrigerant discharged from the second gas outlet. The liquid outlet of the flash assembly is connected to the evaporator. The first end of the first air supply pipeline is connected to the first gas outlet. The second end of the first air supply pipeline is connected to the air supply port. The first end of the second air supply pipeline is connected to the second gas outlet. The second end of the second air supply pipeline is connected to the pipeline between the first compressor and the second compressor. By setting two air supply pipelines, the first air supply pipeline supplies air to the air supply port of the first compressor, and the refrigerant discharged from the second air supply pipeline is mixed with the exhaust gas of the first compressor, so that the flash assembly can supply air to the two compressors more reasonably, improve the utilization rate of the refrigerant, improve the circulation efficiency of the refrigerant, and thus improve the operating energy efficiency of the heat pump system.

[0017] Other features and advantages of the present application will become apparent from the following detailed description of exemplary embodiments of the present application with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0019] Figure 1 This is a schematic diagram of a heat pump system according to some embodiments of the present application. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present application and its application or use. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0021] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the application. Meanwhile, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to actual proportional relationships. The technology, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0022] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" may include both "above" and "below". The device may also be positioned in other different ways, and the spatially relative descriptions used here are interpreted accordingly.

[0023] refer to Figure 1The present application provides a heat pump system, comprising a refrigerant circulation loop, a first air supply pipeline and a second air supply pipeline. The refrigerant circulation loop comprises an evaporator 1, a first compressor 2, a second compressor 3, a condenser 4 and a flash assembly 5 which are sequentially arranged on the flow path of the refrigerant. The air intake of the first compressor 2 is connected to the evaporator 1. The air exhaust of the first compressor 2 is connected to the air intake of the second compressor 3. The first compressor 2 also has an air supply port. The air exhaust of the second compressor 3 is connected to the air inlet of the condenser 4. The flash assembly 5 is connected to the condenser 4 to perform two-stage flashing on the liquid refrigerant discharged from the condenser 4. The flash assembly 5 has an inlet connected to the condenser 4, a liquid outlet for discharging the liquid refrigerant, a first gas outlet for discharging the gaseous refrigerant and a second gas outlet for discharging the gaseous refrigerant. The pressure of the gaseous refrigerant discharged from the first gas outlet is less than the pressure of the gaseous refrigerant discharged from the second gas outlet. The liquid outlet of the flash assembly 5 is connected to the evaporator 1. The first end of the first air supply pipeline 6 is connected to the first gas outlet. The second end of the first air supply pipeline 6 is connected to the air supply port. The first end of the second air supply pipeline 8 is connected to the second gas outlet. The second end of the second air supply pipeline 8 is connected to the pipeline between the first compressor 2 and the second compressor 3.

[0024] By setting up two air supply pipelines, in which the first air supply pipeline 6 supplies air to the air supply port of the first compressor 2, and the refrigerant discharged from the second air supply pipeline 8 is mixed with the exhaust gas of the first compressor 2, the flash assembly 5 can supply air to the two compressors more reasonably, thereby improving the utilization rate of the refrigerant, improving the circulation efficiency of the refrigerant, and thus improving the operating energy efficiency of the heat pump system.

[0025] The heat pump system can be used in the field of industrial waste heat recovery. Based on the heat pump system provided in this application, the efficiency of waste heat recovery is significantly improved by improving the refrigerant utilization rate of the heat pump system.

[0026] For example, during the normal operation of the heat pump system, the evaporator 1 cooperates with the pipeline for the circulation of industrial wastewater, so that the refrigerant in the evaporator 1 absorbs the waste heat in the industrial wastewater and is then absorbed by the first compressor 2. The first compressor 2 heats and pressurizes the refrigerant and discharges it to the second compressor 3. After further heating and pressurizing by the second compressor 3, the high-temperature and high-pressure gaseous refrigerant enters the condenser 4. The refrigerant after releasing energy becomes liquid, and after the action of the flash assembly 5, it becomes gaseous refrigerant again and flows to the evaporator 1. In the process of the refrigerant changing from gas to liquid in the condenser 4, the energy is transferred to the object to be heated (for example, water) in the pipeline cooperating with the condenser 4, and then the industrial waste heat is transferred to the new carrier, so as to realize the recovery and reuse of waste heat, thereby greatly reducing energy consumption and related carbon dioxide emissions.

[0027] refer to Figure 1In some embodiments, the flash assembly 5 includes a first flash chamber 51, a second flash chamber 52 and a throttling assembly 53. The first flash chamber 51 and the second flash chamber 52 are connected in series. The throttling assembly 53 is arranged between the first flash chamber 51 and the second flash chamber 52. The inlet is arranged on the first flash chamber 51. The liquid outlet and the first gas outlet are both arranged on the second flash chamber 52. The second gas outlet is arranged on the first flash chamber 51. After the refrigerant flashes through the first flash chamber 51, the gaseous part is discharged through the second gas outlet, and the liquid part enters the second flash chamber 52 through the throttling assembly 53 and flashes in the second flash chamber 52. The gaseous refrigerant after flashing is discharged through the first gas outlet, and the liquid refrigerant is discharged through the liquid outlet.

[0028] Specifically, the refrigerant first enters the first flash chamber 51 from the condenser 4, and part of the refrigerant in the first flash chamber 51 is discharged through the second gas outlet, and the pressure of the remaining part of the refrigerant is reduced after passing through the throttling component 53 and enters the second flash chamber 52. In the second flash chamber 52, part of this part of the refrigerant is discharged through the first gas outlet in the form of gas, and the remaining liquid part is discharged through the liquid outlet. Through the above process, the refrigerant is flashed in two stages, so that at least part of the refrigerant does not flow to the evaporator 1 through the liquid outlet, but directly enters the condenser 4 after passing through two compressors to participate in the heat exchange cycle. This can significantly improve the utilization rate of the refrigerant and improve the operating energy efficiency of the heat pump system.

[0029] refer to Figure 1 In some embodiments, the heat pump system also includes a third throttle valve 14, which is arranged on the pipeline between the liquid outlet and the evaporator 1, so that the liquid refrigerant discharged through the liquid outlet is converted into a gaseous refrigerant by the third throttle valve 14 and enters the evaporator 1, thereby improving the stability and reliability of the system.

[0030] refer to Figure 1 In some embodiments, the heat pump system further includes a fourth throttle valve 15, which is disposed on a pipeline between the condenser 4 and the inlet of the flash assembly 5, so that the liquid refrigerant in the condenser 4 is converted into a gaseous refrigerant and then enters the first flash chamber 51.

[0031] In some embodiments, the throttling assembly 53 includes a connecting pipeline and a first throttling valve. The first flash chamber 51 and the second flash chamber 52 are connected in series through the connecting pipeline. The first throttling valve is arranged on the connecting pipeline.

[0032] Specifically, in this embodiment, the first flash chamber 51 and the second flash chamber 52 can be two independently arranged flashers, and the two flashers are connected by a connecting pipe. In other words, the flash assembly includes two flashers connected in series, thereby realizing two-stage flashing, and the refrigerant is fully converted into gas and then discharged through two gas supply pipes.

[0033] In some embodiments, the throttling assembly 53 includes a partition and a throttling hole. The partition is configured to separate the internal space of the flash assembly 5 into two areas to form a first flash chamber 51 and a second flash chamber 52. The throttling hole is arranged on the partition.

[0034] Specifically, in this embodiment, the flash assembly 5 is a flasher, and the interior of the flasher is divided into a first flash chamber 51 and a second flash chamber 52 by a partition. Not only can the refrigerant be fully converted into gas and then discharged through two gas supply pipelines, but also the cost of the entire heat pump system is saved.

[0035] refer to Figure 1 In some embodiments, the heat pump system further includes a first control valve 7 . The first control valve 7 is disposed on the first air supply pipeline 6 to control the flow rate of the refrigerant in the first air supply pipeline 6 .

[0036] During the operation of the heat pump system, the first control valve 7 is opened to ensure the stability of operation, and the flow rate of the refrigerant in the first air supply pipeline 6 can be adjusted according to the actual working conditions, thereby adjusting the refrigerant utilization rate and improving the controllability of the entire heat pump system.

[0037] refer to Figure 1 In some embodiments, the heat pump system further includes a second control valve 9. The second control valve 9 is disposed on the second air supply pipeline 8 to control the flow rate of the refrigerant in the second air supply pipeline 8.

[0038] During the operation of the heat pump system, the second control valve 9 is opened to ensure the stability of operation, and the flow rate of the refrigerant in the second air supply pipeline 8 can be adjusted according to the actual working conditions, thereby adjusting the refrigerant utilization rate and improving the controllability of the entire heat pump system.

[0039] refer to Figure 1 In some embodiments, the first compressor 2 comprises a two-stage centrifugal compressor, and the air supply port leads to between two impellers of the two-stage centrifugal compressor.

[0040] Specifically, the pressure of the gaseous refrigerant output by the second air supply pipeline 8 is similar to the pressure of the refrigerant in the heat pump system after being pressurized by the first impeller of the two-stage centrifugal compressor. This can improve the coordination of the air supply of the second air supply pipeline 8 and improve the stability of the heat pump system.

[0041] refer to Figure 1In some embodiments, the second compressor 3 includes a two-stage centrifugal compressor. In this embodiment, the first compressor 2 and the second compressor 3 are both two-stage centrifugal compressors, and the heat pump system achieves four-stage compression of the refrigerant, thereby improving the operating pressure ratio of the heat pump system for the refrigerant, so that the maximum temperature of the refrigerant output to the condenser 4 reaches 120°C, and the temperature rise of the refrigerant is increased to 80K, meeting the application requirements of high temperature and large temperature rise. Combined with the two supplementary pipelines of the flash assembly 5, the system cycle efficiency is significantly improved, the thermodynamic perfection reaches 0.6, and the unit operation energy efficiency is further improved. Taking the object to be heated in the condenser 4 as water as an example, the heat pump system can produce high-temperature hot water at 100~120°C.

[0042] In other embodiments, the second compressor 3 includes a single-stage centrifugal compressor.

[0043] In some embodiments, the refrigerant used in the heat pump system includes R1233zd(E), an environmentally friendly refrigerant, whose global warming potential GWP is less than 1, bringing significant energy-saving and carbon-reduction benefits.

[0044] refer to Figure 1 In some embodiments, the heat pump system further includes a liquid bypass line 10 and a second throttle valve 11 disposed on the liquid bypass line 10. The liquid bypass line 10 is connected between the evaporator 1 and the condenser 4. When the flow rate of the refrigerant required by the evaporator 1 is greater than the flow rate of the refrigerant circulated back to the evaporator 1 from the liquid outlet, the liquid bypass line 10 is configured to be in a connected state so that a portion of the liquid refrigerant in the condenser 4 flows to the evaporator after passing through the liquid bypass line 10 and the second throttle valve 11.

[0045] The flow rate of the refrigerant required by the evaporator 1 does not match the flow rate of the refrigerant normally circulated back to the evaporator 1 by the heat pump system, which will limit the operating energy efficiency of the heat pump system and reduce the efficiency of absorbing industrial waste heat. At this time, the liquid bypass pipeline 10 is opened so that part of the liquid refrigerant in the condenser does not participate in the flashing process of the flashing component 5, but directly flows back to the evaporator 1, thereby increasing the flow rate of the refrigerant in the evaporator 1, ensuring the heat exchange of the evaporator 1, and enhancing the absorption of industrial waste heat.

[0046] After the liquid refrigerant directly flows back to the evaporator 1 through the liquid bypass line 10, the pressure is reduced and it is converted into a gaseous refrigerant after passing through the second throttle valve 11, thereby improving the stability of the heat pump system. In some embodiments, the opening of the second throttle valve 11 is adjustable. In this way, the controllability of the heat pump system can be improved. The second throttle valve 11 can be a solenoid valve or an electronic expansion valve.

[0047] refer to Figure 1In some embodiments, the heat pump system further includes a gas bypass pipeline 12. The gas bypass pipeline 12 is connected between the evaporator 1 and the condenser 4. The gas bypass pipeline 12 can be set to be on and off, so that when the gas bypass pipeline 12 is connected, a part of the refrigerant entering the condenser 4 from the second compressor 3 directly flows back to the evaporator 1 through the gas bypass pipeline 12 to reduce the amount of refrigerant participating in the heat cycle in the heat pump system.

[0048] Setting up the gas bypass line 12 helps to unload the output capacity of the compressor. Specifically, due to the surge phenomenon of the compressor, the output capacity of the compressor is usually adjustable within a certain range. For example, the output capacity of the compressor can be adjusted to a minimum of 40%. When the compressor is working at 40% of the output capacity, the heat pump system's conversion capacity for industrial waste heat is still greater than the actual demand, and it cannot be matched by further reducing the output capacity of the compressor. At this time, the gas bypass line 12 can be opened so that part of the gaseous refrigerant entering the condenser 4 does not participate in the normal heat exchange cycle, but directly returns to the evaporator 1 through the gas bypass line 12, thereby reducing the heat pump system's conversion capacity for industrial waste heat, reducing energy waste, and achieving the purpose of energy conservation and emission reduction.

[0049] refer to Figure 1 In some embodiments, the heat pump system further includes a third control valve 13. The third control valve 13 is disposed on the gas bypass pipeline 12, and the opening of the third control valve 13 is adjustable. Specifically, the third control valve 13 may be an electric butterfly valve or a solenoid valve to improve controllability.

[0050] refer to Figure 1 In some embodiments, the heat pump system further includes a liquid level sensor 16, which is connected to the condenser 4 and is used to detect the liquid level of the liquid refrigerant in the condenser 4. According to the liquid level in the condenser 4, the openings of various throttling components in the heat pump system, such as the first throttle valve, the second throttle valve 11, the third throttle valve 14, and the fourth throttle valve 15, are adjusted to control the liquid level in the condenser 4 to be near the desired value.

[0051] refer to Figure 1 In some embodiments, the heat pump system further includes a check valve 17, which is disposed on a pipeline between the exhaust port of the second compressor 3 and the air inlet of the condenser 4, so as to reduce the risk of high-pressure gas in the condenser 4 flowing back to the compressor at the moment of compressor shutdown, causing the compressor to reverse and resulting in damage to the compressor bearings.

[0052] The specific structural form of the throttle valve in each embodiment of the present application can be an orifice plate, an electric butterfly valve or an electronic expansion valve, etc., as long as the pressure of the refrigerant is reduced when passing through the throttle valve, and there is no specific limitation.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present application rather than to limit it. Although the present application has been described in detail with reference to the preferred embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present application can still be modified or some technical features can be replaced by equivalents without departing from the spirit of the technical solution of the present application, which should be included in the scope of the technical solution for protection in the present application.

Claims

1. A heat pump system, characterized in that: include: A refrigerant circulation loop comprises an evaporator (1), a first compressor (2), a second compressor (3), a condenser (4) and a flash assembly (5) which are sequentially arranged on a refrigerant flow path, wherein an air intake port of the first compressor (2) is connected to the evaporator (1), an air exhaust port of the first compressor (2) is connected to an air intake port of the second compressor (3), the first compressor (2) further comprises an air supply port, an air exhaust port of the second compressor (3) is connected to an air inlet of the condenser (4), the flash assembly (5) is connected to the condenser (4) to perform two-stage flashing of liquid refrigerant discharged from the condenser (4), the flash assembly (5) comprises an inlet connected to the condenser (4), a liquid outlet for discharging liquid refrigerant, a first gas outlet for discharging gaseous refrigerant and a second gas outlet for discharging gaseous refrigerant, the pressure of the gaseous refrigerant discharged from the first gas outlet is lower than the pressure of the gaseous refrigerant discharged from the second gas outlet, and the liquid outlet of the flash assembly (5) is connected to the evaporator (1); a first gas supply pipeline (6), wherein a first end of the first gas supply pipeline (6) is connected to the first gas outlet, and a second end of the first gas supply pipeline (6) is connected to the gas supply port; and A second air supply pipeline (8), wherein a first end of the second air supply pipeline (8) is connected to the second gas outlet, and a second end of the second air supply pipeline (8) is connected to a pipeline between the first compressor (2) and the second compressor (3).

2. The heat pump system according to claim 1, characterized in that: The flash assembly (5) comprises a first flash chamber (51), a second flash chamber (52) and a throttling assembly (53); the first flash chamber (51) and the second flash chamber (52) are connected in series; the throttling assembly (53) is arranged between the first flash chamber (51) and the second flash chamber (52); the inlet is arranged on the first flash chamber (51); the liquid outlet and the first gas outlet are both arranged on the second flash chamber (52); the second gas outlet is arranged on the first flash chamber (51); after the refrigerant flashes through the first flash chamber (51), the gaseous part is discharged through the second gas outlet, and the liquid part enters the second flash chamber (52) through the throttling assembly (53) and flashes in the second flash chamber (52); the gaseous refrigerant after flashing is discharged through the first gas outlet, and the liquid refrigerant is discharged through the liquid outlet.

3. The heat pump system according to claim 2, characterized in that: The throttling assembly (53) comprises a connecting pipeline and a first throttling valve, the first flash chamber (51) and the second flash chamber (52) are connected in series via the connecting pipeline, and the first throttling valve is arranged on the connecting pipeline.

4. The heat pump system according to claim 2, characterized in that: The throttling assembly (53) comprises a partition and a throttling hole, the partition being configured to separate the internal space of the flash assembly (5) into two areas to form the first flash chamber (51) and the second flash chamber (52), and the throttling hole is arranged on the partition.

5. The heat pump system according to any one of claims 1 to 4, characterized in that: It also comprises a first control valve (7), wherein the first control valve (7) is arranged on the first air supply pipeline (6) to control the flow rate of the refrigerant in the first air supply pipeline (6).

6. The heat pump system according to any one of claims 1 to 4, characterized in that: It also comprises a second control valve (9), wherein the second control valve (9) is arranged on the second air supply pipeline (8) to control the flow rate of the refrigerant in the second air supply pipeline (8).

7. The heat pump system according to any one of claims 1 to 4, characterized in that: The first compressor (2) comprises a two-stage centrifugal compressor, and the air supply port leads to between two impellers of the two-stage centrifugal compressor.

8. The heat pump system according to any one of claims 1 to 4, characterized in that: It also includes a liquid bypass pipeline (10) and a second throttle valve (11) arranged on the liquid bypass pipeline (10), wherein the liquid bypass pipeline (10) is connected between the evaporator (1) and the condenser (4), and when the flow rate of the refrigerant required by the evaporator (1) is greater than the flow rate of the refrigerant circulated back to the evaporator (1) from the liquid outlet, the liquid bypass pipeline (10) is configured to be in a connected state so that a part of the liquid refrigerant in the condenser (4) flows to the evaporator after passing through the liquid bypass pipeline (10) and the second throttle valve (11).

9. The heat pump system according to claim 8, characterized in that: The opening degree of the second throttle valve (11) is adjustable.

10. The heat pump system according to any one of claims 1 to 4, characterized in that: The heat pump system further comprises a gas bypass pipeline (12), wherein the gas bypass pipeline (12) is connected between the evaporator (1) and the condenser (4), and the gas bypass pipeline (12) can be switched on and off so that when the gas bypass pipeline (12) is connected, a portion of the refrigerant entering the condenser (4) from the second compressor (3) directly flows back to the evaporator (1) through the gas bypass pipeline (12), thereby reducing the amount of refrigerant participating in the heat cycle in the heat pump system.

11. The heat pump system according to claim 10, characterized in that: It also comprises a third control valve (13), wherein the third control valve (13) is arranged on the gas bypass pipeline (12), and the opening degree of the third control valve (13) is adjustable.

Images