A piping system

Abstract

The embodiment of the present application provides a pipeline system, comprising a refrigeration cycle circuit composed of a condenser, a refrigerant pump, a throttling element, an evaporator and a compressor, and a cooling branch circuit composed of the condenser, the refrigerant pump, the compressor and a heating assembly; high-pressure liquid refrigerant is divided into two paths after being output from the condenser and passing through the refrigerant pump, wherein one path of the high-pressure liquid refrigerant sequentially passes through the throttling element, the evaporator and the suction port of the compressor, and then returns to the condenser, thereby completing a refrigeration cycle circuit; the other path of the high-pressure liquid refrigerant is input into the internal flow path of the compressor to form gas-liquid two-phase refrigerant, the gas-liquid two-phase refrigerant passes through the heating assembly to form superheated gaseous refrigerant, and then returns to the suction port of the compressor, thereby completing the cooling branch circuit. The refrigeration system can avoid damage to the compressor caused by gas-liquid two-phase refrigerant directly returning to the compression module of the compressor, and is stable in operation.

Description

Technical Field

[0001] This invention relates to the field of refrigeration system technology, and more particularly to a piping system. Background Technology

[0002] With the development of information technology, data centers need to store and process a large amount of data every day. The process of storing and processing data consumes a lot of energy and emits a lot of heat. The accumulation of heat will cause the data center to malfunction. Therefore, it is necessary to install a cooling system in the data center to reduce the heat.

[0003] In the existing technology, please refer to Figure 1 The cooling system used in data centers mainly consists of a condenser, refrigerant pump, throttling element, evaporator, and compressor. The condenser, refrigerant pump, throttling element, evaporator, and compressor are connected in sequence through pipes to form a circulation system. The refrigerant circulates through each component in the pipes to transport heat. The specific circulation path is as follows: the refrigerant pump drives the liquid refrigerant to the throttling element for throttling. The throttled refrigerant is heated at the evaporator (the heat comes from the data center) to form gaseous refrigerant. The gaseous refrigerant flows to the compressor, and after compression, it is heated and pressurized and flows to the condenser. The gaseous refrigerant releases heat in the condenser and returns to the liquid state. Then it flows back to the refrigerant pump to start the next cycle.

[0004] For the compressor, the core component of a refrigeration system, the commonly used types include screw compressors, centrifugal compressors, and magnetic levitation compressors. These three types of compressors generate a large amount of heat during operation (such as motors and bearings), thus requiring cooling. Existing cooling methods typically involve a cooling supply branch after the liquid refrigerant flows through the refrigerant pump. The refrigerant then flows to the compressor through this branch, cooling its components. The cooled refrigerant is generally in a gas-liquid two-phase mixture, flowing untreated to the compressor's suction port. However, it is crucial to prevent liquid refrigerant from returning to the compressor during operation: if liquid refrigerant enters a screw compressor, it will damage the compressor rotor oil film, leading to rotor lubrication failure, dry running, or even seizure; if liquid refrigerant enters a centrifugal compressor, it will cause wear on the compressor blades; if liquid refrigerant enters a magnetic levitation compressor, it may damage the compressor; and the return of two-phase refrigerant to the compressor suction port may trigger surge protection or bearing protection, causing the unit to shut down and potentially leading to temperature control issues within the data center. Summary of the Invention

[0005] This invention provides a piping system to solve the problem in the prior art where gas-liquid two-phase refrigerant flowing into the compressor's suction port can damage the compressor.

[0006] In this embodiment of the invention, the piping system includes a refrigeration cycle loop consisting of a condenser, a refrigerant pump, a throttling element, an evaporator, and a compressor, and further includes a cooling branch consisting of the condenser, the refrigerant pump, the compressor, and a heating assembly;

[0007] After the high-pressure liquid refrigerant is output from the condenser, it is divided into two paths after passing through the refrigerant pump. One path of high-pressure liquid refrigerant is throttled by the throttling element into a two-phase gas-liquid refrigerant, and then evaporated by the evaporator to absorb heat and become a low-temperature, low-pressure superheated gaseous refrigerant. The superheated gaseous refrigerant is input to the suction port of the compressor, and after the compressor works, it generates a high-pressure, high-temperature gaseous refrigerant. The high-pressure, high-temperature gaseous refrigerant returns to the condenser to be cooled into a high-pressure liquid refrigerant, thus completing a refrigeration cycle.

[0008] Furthermore, the other high-pressure liquid refrigerant is input into the internal flow path of the compressor for cooling, forming a gas-liquid two-phase refrigerant. The gas-liquid two-phase refrigerant is heated by the heating component to form a superheated gaseous refrigerant, which then returns to the compressor suction port, thereby completing the cooling branch.

[0009] As a further alternative to the piping system, the heating component is configured as a heat exchanger, and in the cooling branch, the gas-liquid two-phase refrigerant exchanges heat with the compressor exhaust when passing through the heat exchanger.

[0010] As a further alternative to the piping system, the condenser includes a first condenser and a second condenser connected in parallel. The high-pressure, high-temperature gaseous refrigerant generated after the compressor operates is divided into two paths, including a main path and a branch path. The high-pressure, high-temperature gaseous refrigerant in the main path directly enters the first condenser, while the high-pressure, high-temperature gaseous refrigerant in the branch path enters the second condenser after exchanging heat with the heat exchanger.

[0011] As a further optional feature of the pipeline system, the main pipeline and / or the branch pipeline are equipped with control valves for controlling the flow rate of high-pressure, high-temperature gaseous refrigerant.

[0012] As a further alternative to the piping system, the control valve is configured as an electric valve.

[0013] As a further alternative to the pipeline system, in the branch, the high-pressure, high-temperature gaseous refrigerant enters the heat exchanger and exchanges heat with the gas-liquid two-phase refrigerant in the heat exchanger before entering the second condenser to be cooled into high-pressure liquid refrigerant.

[0014] As a further alternative to the piping system, the heat exchanger is a plate heat exchanger.

[0015] As a further alternative to the piping system, the heat exchanger piping is disposed on the outer surface of the condenser, and the high-pressure, high-temperature gaseous refrigerant enters the condenser to exchange heat with the gas-liquid two-phase refrigerant in the heat exchange piping.

[0016] As a further alternative to the piping system, the heat exchanger piping is arranged in a wound manner on the outer surface of the condenser.

[0017] As a further alternative to the piping system, in the cooling branch, the high-pressure liquid refrigerant is input into the internal flow path of the compressor to cool the compressor's own motor and bearings.

[0018] Implementing the embodiments of the present invention will have the following beneficial effects:

[0019] This invention adds a heating component, which heats the gas-liquid two-phase refrigerant formed during cooling in the compressor's internal flow path, transforming it into a superheated gaseous refrigerant that returns to the compressor's suction port. This heating process prevents the refrigerant from returning to the compressor suction port in liquid form, thus avoiding the frequent occurrence of compressor surge protection, bearing protection, and ultimately unit alarm shutdowns and uncontrolled machine room temperatures caused by the backflow of two-phase refrigerant to the compressor suction port. This significantly improves the reliability of unit operation, especially under low load conditions. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] in:

[0022] Figure 1 This is a schematic diagram of the structure of a refrigeration pipeline in the prior art;

[0023] Figure 2 This is a schematic diagram of the pipeline structure in one embodiment of the present invention;

[0024] Figure 3 This is a schematic diagram of the pipeline system in another embodiment of the present invention;

[0025] In the diagram: 10-Condenser; 11-First condenser; 12-Second condenser; 20-Refrigerant pump; 30-Throttling element; 40-Evaporator; 50-Compressor; 60-Heat exchanger; 70-Control valve. Detailed Implementation

[0026] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many other different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0027] It should be noted that when a component is said to be "fixed to" another component, it can be directly attached to the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0029] This invention provides a refrigeration system with a gas-liquid two-phase refrigerant heating function, which solves the problem in the prior art that the gas-liquid two-phase refrigerant will damage the compressor after flowing into the compressor's suction port.

[0030] In the embodiments of the present invention, please refer to the references. Figure 2 and Figure 3 The piping system includes a refrigeration cycle loop consisting of a condenser 10, a refrigerant pump 20, a throttling element 30, an evaporator 40, and a compressor 50. It also includes a cooling branch consisting of the condenser 10, the refrigerant pump 20, the compressor 50, and a heating component. In this embodiment, the heating component mainly uses a heat exchanger 60. In addition to the heat exchanger 60, the heating component can also use electric heating or other devices with heating functions. The function of the heating component is to heat the gas-liquid two-phase refrigerant formed in the internal flow path of the compressor 50, so that it can return to the compressor suction port in gaseous form. This is to prevent the two-phase refrigerant from frequently causing the compressor to surge protection, bearing protection, etc., before flowing back to the compressor suction port, which would eventually cause the unit to alarm and shut down, resulting in uncontrolled temperature in the machine room.

[0031] The high-pressure liquid refrigerant, after being output from the condenser 10, is divided into two paths after passing through the refrigerant pump 20. One path of high-pressure liquid refrigerant is throttled by the throttling element 30 into a two-phase gas-liquid refrigerant, and then evaporates into a low-temperature, low-pressure superheated gaseous refrigerant through the evaporator 40. The superheated gaseous refrigerant is input to the suction port of the compressor 50, and after the compressor 50 operates, it generates a high-pressure, high-temperature gaseous refrigerant. The high-pressure, high-temperature gaseous refrigerant returns to the condenser 10 to be cooled into a high-pressure liquid refrigerant, thus completing one refrigeration cycle. The other path of high-pressure liquid refrigerant is input into the internal flow path of the compressor 50 for cooling, forming a two-phase gas-liquid refrigerant. The two-phase gaseous refrigerant passes through the heat exchanger 60 to form a superheated gaseous refrigerant, and then returns to the suction port of the compressor 10, thus completing the cooling branch.

[0032] This invention adds a heating component, which heats the gas-liquid two-phase refrigerant formed during cooling in the internal flow path of the compressor 50, turning it into superheated gaseous refrigerant that returns to the compressor 50's suction port. This heating process prevents the refrigerant from returning to the compressor 50's suction port in liquid form, thus preventing the frequent backflow of two-phase refrigerant into the compressor 50's suction port, which could lead to surge protection, bearing protection, and ultimately unit alarm shutdowns and uncontrolled machine room temperatures. This significantly improves the reliability of the unit's operation, especially under low load conditions.

[0033] In this embodiment of the invention, the heating component can heat the gas-liquid two-phase refrigerant using its own heat source, or it can use the heat of the high-pressure, high-temperature gaseous refrigerant to heat the gas-liquid two-phase refrigerant.

[0034] In one embodiment, the heating assembly includes a body and a heater. The body has a cavity for passing a gas-liquid two-phase refrigerant, and the heater is used to heat the cavity so that the gas-liquid two-phase refrigerant is completely converted into a gaseous state.

[0035] In another embodiment, in the cooling branch, the heating component adopts a heat exchanger 60, and the gas-liquid two-phase refrigerant exchanges heat with the exhaust gas of the compressor 50 when passing through the heat exchanger 60.

[0036] In one specific embodiment, please refer to Figure 2 The heat exchanger 60 has a first passage and a second passage. The first passage connects the exhaust port of the compressor 50 and the condenser 10, and is used for the passage of high-pressure, high-temperature gaseous refrigerant. The second passage connects the internal flow path and the suction port of the compressor 50, and is used for the passage of gas-liquid two-phase refrigerant. The first passage and the second passage can exchange heat, so that the gas-liquid two-phase refrigerant is completely converted into a gaseous state. In this embodiment, the heat exchange of the refrigerant in the first passage and the second passage can be achieved by designing the spatial arrangement of the first passage and the second passage, such as arranging the first passage and the second passage adjacent to each other, intertwined, or nested.

[0037] In a more specific embodiment, the heat exchanger 60 includes a first pipe and a second pipe, the inner diameter of the second pipe being larger than the outer diameter of the first pipe, the first pipe and the second pipe being coaxially arranged, and the second pipe being nested outside the first pipe. In this case, the first pipe forms a first passage for passing high-pressure gaseous refrigerant, and the gap between the second pipe and the first pipe forms a second passage for passing gaseous two-phase refrigerant.

[0038] In another, more specific embodiment, the heat exchanger 60 is configured as a plate heat exchanger, which has hot medium channels and cold medium channels formed within it. The hot medium channels form a first passage, and the cold medium channels form a second passage. Plate heat exchangers are a relatively mature heat exchange element in the prior art. Their main structure includes multiple stacked metal plates with tortuous liquid channels formed between them. Part of these channels serves as hot medium channels for the passage of high-pressure, high-temperature gaseous refrigerant, while another part serves as cold medium channels for the passage of a two-phase gas-liquid refrigerant. The fluids in the hot and cold medium channels can rapidly exchange heat through the thermal conductivity of the metal plates. Since the structure of the plate heat exchanger in this invention adopts existing designs, it will not be described in detail here.

[0039] In one embodiment, where the heat used by the heat exchanger 60 to heat the gas-liquid two-phase refrigerant originates from the exhaust gas of the compressor 50, please refer to... Figure 3 The condenser 10 includes a first condenser 11 and a second condenser 12 arranged in parallel. The high-pressure, high-temperature gaseous refrigerant generated after the compressor operates is divided into two paths, including a main path and a branch path. The high-pressure, high-temperature gaseous refrigerant in the main path directly enters the first condenser 11, while the high-pressure, high-temperature gaseous refrigerant in the branch path enters the second condenser 12 after exchanging heat with the heat exchanger 60.

[0040] The advantage of this embodiment is that only a portion of the high-pressure gaseous refrigerant is separated for heating the gas-liquid two-phase refrigerant, while the other portion passes directly through the condenser 10 to accelerate the circulation of the refrigerant, thereby ensuring that the temperature inside the data center is maintained within a reasonable range.

[0041] In one specific embodiment, a control valve 70 for controlling the flow rate of high-pressure, high-temperature gaseous refrigerant is provided in the main circuit and / or branch circuit. The control valve 70 ensures that the flow rate of the high-pressure, high-temperature gaseous refrigerant used for heating the gas-liquid two-phase refrigerant is maintained within a reasonable range.

[0042] In a more specific embodiment, the control valve 70 is configured as an electric valve.

[0043] In a more specific embodiment, in the branch circuit, the high-pressure, high-temperature gaseous refrigerant enters the heat exchanger 60 and exchanges heat with the gas-liquid two-phase refrigerant in the heat exchanger 60 before entering the second condenser 12 to be cooled into high-pressure liquid refrigerant.

[0044] In one embodiment, where the heat used by the heat exchanger 60 to heat the gas-liquid two-phase refrigerant originates from the exhaust gas of the compressor 50, the heat exchange pipes of the heat exchanger 60 are disposed on the outer surface of the condenser 10. High-pressure, high-temperature gaseous refrigerant enters the condenser 10 and exchanges heat with the gas-liquid two-phase refrigerant in the heat exchange pipes. Specifically, after entering the condenser 10, the high-pressure, high-temperature gaseous refrigerant cools into a high-pressure liquid refrigerant, releasing a large amount of heat in the process. This heat is transferred to the gas-liquid two-phase refrigerant through the heat exchange pipes of the heat exchanger 60, thereby heating the gas-liquid two-phase refrigerant and converting it into superheated gaseous refrigerant.

[0045] In one specific embodiment, the heat exchanger 60's heat exchange tubing is arranged in a wound manner on the outer surface of the condenser 10.

[0046] The advantage of using this winding method is that it increases the length of the heat exchange pipe in contact with the condenser 10, thereby increasing the heat exchange efficiency.

[0047] In other specific embodiments, the heat exchange pipeline of the heat exchanger 60 may also be arranged on the outer surface of the condenser 10 in a straight line or serpentine manner.

[0048] In one embodiment, in the cooling branch, high-pressure liquid refrigerant is introduced into the internal flow path of the compressor 50 to cool the compressor 50's own motor and bearings.

[0049] In some embodiments, the throttling element may be one of a capillary tube, a throttling tube, a thermostatic expansion valve, an electronic expansion valve, a float valve, a thermostatic expansion valve, and an electronic expansion valve.

[0050] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0051] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A piping system applied to a centrifugal compressor refrigeration system, characterized in that, It includes a refrigeration cycle loop consisting of a condenser, a refrigerant pump, a throttling element, an evaporator, and a compressor, and further includes a cooling branch consisting of the condenser, the refrigerant pump, the compressor, and a heating assembly; After the high-pressure liquid refrigerant is output from the condenser, it is divided into two paths after passing through the refrigerant pump. One path of high-pressure liquid refrigerant is throttled by the throttling element into a two-phase gas-liquid refrigerant, and then evaporated by the evaporator to absorb heat and become a low-temperature, low-pressure superheated gaseous refrigerant. The superheated gaseous refrigerant is input to the suction port of the compressor, and after the compressor works, it generates a high-pressure, high-temperature gaseous refrigerant. The high-pressure, high-temperature gaseous refrigerant returns to the condenser to be cooled into a high-pressure liquid refrigerant, thus completing a refrigeration cycle. Furthermore, the other high-pressure liquid refrigerant is input into the internal flow path of the compressor for cooling, forming a gas-liquid two-phase refrigerant. The gas-liquid two-phase refrigerant is heated by the heating component to form a superheated gaseous refrigerant, which then returns to the compressor suction port, thereby completing the cooling branch. The heating component is configured as a heat exchanger. In the cooling branch, the gas-liquid two-phase refrigerant exchanges heat with the compressor exhaust when passing through the heat exchanger. The heat exchanger has a first passage and a second passage; the first passage is connected between the exhaust port of the compressor and the condenser for passing high-pressure, high-temperature gaseous refrigerant, and the second passage is connected between the internal flow path and the suction port of the compressor for passing gas-liquid two-phase refrigerant. The first passage and the second passage can exchange heat. The condenser includes a first condenser and a second condenser connected in parallel. The high-pressure, high-temperature gaseous refrigerant generated after the compressor operates is divided into two paths, including a main path and a branch path. The high-pressure, high-temperature gaseous refrigerant in the main path directly enters the first condenser, while the high-pressure, high-temperature gaseous refrigerant in the branch path enters the second condenser after exchanging heat with the heat exchanger.

2. The piping system according to claim 1, characterized in that, The main road and / or the branch road are equipped with control valves for controlling the flow rate of high-pressure, high-temperature gaseous refrigerant.

3. The piping system according to claim 2, characterized in that, The control valve is configured as an electric valve.

4. The piping system according to claim 2, characterized in that, In the branch circuit, the high-pressure, high-temperature gaseous refrigerant enters the heat exchanger and exchanges heat with the gas-liquid two-phase refrigerant in the heat exchanger before entering the second condenser to be cooled into high-pressure liquid refrigerant.

5. The piping system according to any one of claims 2-4, characterized in that, The heat exchanger is a plate heat exchanger.

6. The piping system according to claim 2 or 3, characterized in that, The heat exchanger's heat exchange pipes are arranged on the outer surface of the condenser. The high-pressure, high-temperature gaseous refrigerant enters the condenser and exchanges heat with the gas-liquid two-phase refrigerant in the heat exchange pipes.

7. The piping system according to claim 6, characterized in that, The heat exchanger's heat exchange tubing is wound around the outer surface of the condenser.

8. The piping system according to claim 1, characterized in that, In the cooling branch, the high-pressure liquid refrigerant is input into the internal flow path of the compressor to cool the compressor's own motor and bearings.

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