Multi-machine-head air-cooled water chilling unit refrigerating system and refrigerating equipment

Abstract

The system comprises N refrigerant circulating flow paths, each refrigerant circulating flow path comprises a refrigerant main pipeline, and an electronic expansion valve, a refrigerant pipeline of an evaporator, a compressor and a plurality of refrigerant branch pipelines connected in parallel are sequentially arranged between the head and the tail of the refrigerant main pipeline in series. The plurality of refrigerant branch pipelines are respectively connected with the M air-cooled condensers, N is a natural number greater than or equal to 2, M is a natural number greater than or equal to 1, and the M air-cooled condensers are shared by the N refrigerant circulating flow paths; and the water path pipelines of the evaporators in the N refrigerant circulating flow paths which are arranged in the positive sequence are sequentially connected between the head and the tail of the heat exchange water pipeline in series, and the refrigerant inlet and outlet between the air inlet side and the air outlet side of each air-cooled condenser is connected with the corresponding refrigerant branch pipelines in the N refrigerant circulating flow paths which are arranged in the reverse sequence. The problems that in the prior art, due to the fact that the running pressure ratio of multiple compressors is unbalanced, the refrigerating capacity is low, and energy consumption is high can be solved.

Description

Technical Field

[0001] The present application relates to the field of refrigeration technology, and in particular to a multi-head air-cooled chiller refrigeration system and refrigeration equipment. Background Art

[0002] In existing air-cooled screw units or air-cooled magnetic levitation centrifugal units, when there are multiple compressors (multiple compressors correspond to multiple refrigeration systems) running at the same time, the general design scheme is: each compressor is equipped with an independent refrigerant circuit, the evaporator adopts a shell and tube heat exchanger, and the condenser adopts an air-cooled fin tube or microchannel structure. The condenser inlet air temperature of all refrigerant circuits is the same, and the evaporator side adopts a two-flow or multi-flow design of hot water exchange pipelines to form multiple independent refrigerant loops. This design can ensure that the evaporation pressure of multiple refrigerant loops is not much different, and the condensation pressure is not much different, so that the pressure ratio is not much different, but the efficiency is not high.

[0003] Another design scheme is to use a series evaporator, where the outlet water of the evaporator of the first refrigeration system flows into the evaporator of the second refrigeration system. However, the condensers of the two refrigeration systems still use the same inlet air temperature. Although this scheme increases the evaporation temperature of the first refrigeration system, that is, the evaporation temperature corresponding to the water inlet side is higher, compared with the previous scheme, the first refrigeration system can produce a relatively large cooling capacity; however, the outlet water side of the evaporator of the second refrigeration system still corresponds to a higher condensation temperature, which will lead to a higher pressure ratio, and there is still a problem of high energy consumption. Summary of the invention

[0004] In view of this, the main purpose of this application is to provide a multi-head air-cooled chiller refrigeration system and refrigeration equipment, which is conducive to solving the problem of low cooling capacity and high energy consumption caused by uneven operating pressure ratio of multiple compressors in the prior art.

[0005] The present application provides a multi-head air-cooled chiller refrigeration system, which includes N refrigerant circulation flow paths, each of which includes: a refrigerant main pipeline, an electronic expansion valve, a refrigerant pipeline for an evaporator, a compressor, and a plurality of refrigerant branch pipelines in parallel, wherein the plurality of refrigerant branch pipelines are respectively connected to M air-cooled condensers, wherein N is a natural number greater than or equal to 2, and M is a natural number greater than or equal to 1, and the M air-cooled condensers are shared by the N refrigerant circulation flow paths; a hot water exchange water pipeline, wherein the water pipelines of the evaporators in the N refrigerant circulation flow paths arranged in positive sequence are connected in series between the head and the tail, wherein the corresponding refrigerant branch pipelines in the N refrigerant circulation flow paths arranged in reverse sequence are connected to the refrigerant inlet and outlet between the air inlet side and the air outlet side of each air-cooled condenser.

[0006] From the above, N refrigerant circulation flow paths share M air-cooled condensers, that is, the refrigerant branch pipes arranged in each refrigerant circulation flow path are connected to M air-cooled condensers, and the arrangement order of the N refrigerant circulation flow paths between the water inlet end of the hot water exchange pipe and the water outlet end is opposite to the arrangement order between the air inlet side and the air outlet side of each air-cooled condenser. Through this design, in each air-cooled condenser, the air inlet temperature of the refrigerant in the refrigerant branch pipes in the N refrigerant circulation flow paths is different, so that the evaporation temperature of the evaporator in the refrigerant circulation flow path adjacent to the water outlet end of the hot water exchange pipe corresponds to a lower condensation temperature, thereby reducing the operating pressure ratio of the compressor in the refrigerant circulation flow path, so that the energy consumption of this part is significantly reduced, and the compressor pressure ratio in the N refrigerant circulation flow paths is balanced, achieving the purpose of increasing the cooling capacity and reducing energy consumption.

[0007] Optionally, when N is 2 and M is 2, the refrigerant circulation circuit includes a first refrigerant circulation circuit and a second refrigerant circulation circuit, wherein the first refrigerant circulation circuit is arranged adjacent to the water inlet end of the hot water exchange pipe, and the second refrigerant circulation circuit is arranged adjacent to the water outlet end of the hot water exchange pipe.

[0008] Optionally, the refrigerant branch pipes in the first refrigerant circulation flow circuit are respectively connected in parallel to the refrigerant inlets and outlets on the air outlet sides of the two air-cooled condensers.

[0009] From the above, the first refrigerant circulation flow path is connected in parallel at the air outlet sides of the two air-cooled condensers through a plurality of refrigerant branch pipelines arranged in parallel; when each air-cooled condenser adopts a V-shaped fin tube structure, the first refrigerant circulation flow path is provided with four refrigerant branch pipelines in parallel, and every two refrigerant branch pipelines are sequentially connected to the refrigerant inlet and outlet ends of the V-shaped fin tube of each air-cooled condenser, and are arranged close to the air outlet side of each air-cooled condenser. When each air-cooled condenser adopts an inverted M-shaped fin tube structure, the first refrigerant circulation flow path is provided with eight refrigerant branch pipelines in parallel, and every four refrigerant branch pipelines are sequentially connected to the refrigerant inlet and outlet ends of the inverted M-shaped fin tube of each air-cooled condenser, and are arranged close to the air outlet side of each air-cooled condenser.

[0010] Optionally, the refrigerant branch pipes in the second refrigerant circulation flow circuit are respectively connected in parallel to the refrigerant inlet and outlet on the air inlet side of the two air-cooled condensers.

[0011] From the above, the second refrigerant circulation flow path is connected in parallel at the air inlet side of the two air-cooled condensers through a plurality of refrigerant branch pipelines arranged in parallel; when each air-cooled condenser adopts a V-shaped fin tube structure, the second refrigerant circulation flow path is arranged in parallel with four refrigerant branch pipelines, and every two refrigerant branch pipelines are sequentially connected to the refrigerant inlet and outlet ends of the V-shaped fin tube of each air-cooled condenser, and are arranged close to the air inlet side of each air-cooled condenser. When each air-cooled condenser adopts an inverted M-shaped fin tube structure, the first refrigerant circulation flow path is arranged in parallel with eight refrigerant branch pipelines, and every four refrigerant branch pipelines are sequentially connected to the refrigerant inlet and outlet ends of the inverted M-shaped fin tube of each air-cooled condenser, and are arranged close to the air inlet side of each air-cooled condenser.

[0012] Optionally, when N is a natural number greater than 2, the refrigerant circulation flow path includes a first refrigerant circulation flow path, a second refrigerant circulation flow path to an Nth refrigerant circulation flow path, wherein the first refrigerant circulation flow path, the second refrigerant circulation flow path to the Nth refrigerant circulation flow path are arranged in sequence between the water inlet end and the water outlet end of the hot water exchange pipe.

[0013] Optionally, the refrigerant branch pipes in the first refrigerant circulation flow path, the second refrigerant circulation flow path to the Nth refrigerant circulation flow path are arranged in reverse order and connected to the refrigerant inlet and outlet between the air inlet side and the air outlet side of each air-cooled condenser.

[0014] Optionally, the refrigerants in the N refrigerant circulation circuits have the same flow direction in their respective corresponding refrigerant branch pipes.

[0015] From the above, when the refrigerant in all refrigerant pipes flows in the same direction, it can ensure that the temperature distribution in the entire system is more uniform.

[0016] On the other hand, the present application also provides a refrigeration device, which includes any one of the multi-head air-cooled chiller refrigeration systems described above.

[0017] From the above, the refrigeration equipment is not limited to small or large chillers, household air conditioners, industrial cooling systems and other occasions, nor is it limited to application fields such as hospitals, scientific research institutions, office buildings, and production plants.

[0018] In summary, the present application provides a multi-head air-cooled chiller refrigeration system and refrigeration equipment. In the multi-head air-cooled chiller refrigeration system, the refrigerant sub-pipeline in the refrigerant circulation flow path arranged closer to the water outlet end of the hot water exchange pipe is arranged closer to the air inlet side of each air-cooled condenser, so that the temperature of the refrigerant in the refrigerant sub-pipeline in each refrigerant circulation flow path is different, so that the compressor pressure ratio in the multiple refrigerant circulation flow paths is balanced, thereby achieving the purpose of increasing the cooling capacity of the refrigerant circulation flow path arranged closer to the water outlet of the hot water exchange pipe and reducing its energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The various technical features of the present application and the relationship between them are further explained below with reference to the accompanying drawings. The accompanying drawings are exemplary, and some technical features are not shown in actual proportion. In addition, some drawings may omit technical features that are commonly used in the technical field to which the present application belongs and are not essential for understanding and implementing the present application, or additional technical features that are not essential for understanding and implementing the present application may be shown. In other words, the combination of the various technical features shown in the accompanying drawings is not used to limit the present application. In addition, throughout the present application, the same figure numbers refer to the same content. The specific description of the drawings is as follows:

[0020] Figure 1 This is an embodiment diagram of a multi-head air-cooled chiller refrigeration system in the present application;

[0021] Figure 2 It is an embodiment diagram of the prior art in this application.

[0022] Description of Reference Numerals

[0023] 11-first fully-liquid evaporator, 12-first compressor, 13-first electronic expansion valve, 21-second fully-liquid evaporator, 22-second compressor, 23-second electronic expansion valve, 31-first air-cooled condenser, 32-second air-cooled condenser, 11′-high-temperature side evaporator, 12′-high-temperature side compressor, 13′-high-temperature side electronic expansion valve, 21′-low-temperature side evaporator, 22′-low-temperature side compressor, 23′-low-temperature side electronic expansion valve, 31′-high-temperature side condenser, 32′-low-temperature side condenser.

[0024] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0025] The preferred embodiments of the present application are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present application can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present application.

[0026] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0027] Figure 2 A conventional two-compressor refrigeration system is shown, each compressor having an independent refrigerant circuit. Since the water temperature at the water inlet of the hot water exchange pipe is relatively high, the refrigeration system arranged therein is a high-temperature side refrigeration system (which can be referred to as the high-temperature side). Similarly, the refrigeration system arranged at the water outlet of the hot water exchange pipe is a low-temperature side refrigeration system (which can be referred to as the low-temperature side). The inlet air temperature of the high-temperature side condenser 31′ and the low-temperature side condenser 32′ are the same, while the inlet water temperature of the high-temperature side evaporator 11′ is relatively high. The outlet water temperature of the high-temperature side evaporator 11′ is equal to the inlet water temperature of the low-temperature side evaporator 21′. The high-temperature side refrigeration system has a relatively high evaporation temperature and condensation temperature, while the outlet water of the high-temperature side evaporator 11′ enters the low-temperature side evaporator 21′ for continued heat exchange and cooling, resulting in the outlet water temperature of the low-temperature side evaporator 21′ being lower than the outlet water temperature of the high-temperature side evaporator 11′. Therefore, the evaporation pressure of the low-temperature side refrigeration system is lower than the evaporation pressure of the high-temperature side refrigeration system. Although the air inlet temperatures of the condensers (31′, 32′) of the two refrigeration systems are the same, their air outlet temperatures will be slightly different due to the difference in evaporation pressure, which will cause the operating pressure ratio of the low-temperature side compressor 22′ to be greater than the operating pressure ratio of the high-temperature side compressor 12′, and thus the cooling capacity of the low-temperature side compressor 22′ is lower than the cooling capacity of the high-temperature side compressor 12′, and the operating energy consumption of the low-temperature side compressor 22′ is greater than the operating energy consumption of the high-temperature side compressor 12′.

[0028] For large water-cooled centrifugal units, in order to balance the pressure ratio of the two refrigeration systems, improve energy efficiency and increase cooling capacity, a series countercurrent solution can be adopted. Taking a two-compressor refrigeration system as an example, the compressor in the first refrigeration system corresponds to the water inlet side of the system evaporator, and the compressor in the first refrigeration system corresponds to the water outlet side of the system condenser; the system evaporator water inlet temperature is high, and the system condenser water outlet temperature is also high, that is, high evaporation temperature and high condensation temperature. The compressor in the second refrigeration system corresponds to the water outlet side of the system evaporator and the water inlet side of the system condenser, which means that a low evaporation temperature corresponds to a lower condensation temperature, which ensures that the condensation temperature of the second refrigeration system is reduced, thereby reducing the corresponding compressor pressure ratio, and energy consumption is also reduced, and a lower pressure ratio usually increases a certain amount of cooling capacity output.

[0029] This application optimizes system performance by making the air inlet temperature of the condensers in different refrigeration systems different. Specifically, the air inlet temperature of the low-temperature side condenser is the ambient air temperature. After absorbing heat, the air temperature rises and then enters the high-temperature side condenser to continue absorbing heat. This design ensures that the operating pressure ratio of the low-temperature side refrigeration system is significantly lower than that of traditional air cooling, thereby increasing the cooling capacity of the low-temperature side refrigeration system and reducing the operating energy consumption of its compressor.

[0030] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments. The specific embodiments described below can be combined with each other to form new embodiments. The same or similar ideas or processes described in one embodiment may not be repeated in other embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0031] The present application provides a multi-head air-cooled chiller refrigeration system, which includes N refrigerant circulation flow paths, each of which includes: a refrigerant main pipeline, a refrigerant pipeline with an electronic expansion valve and an evaporator arranged in series between the head and the tail of the refrigerant main pipeline, a compressor, and multiple refrigerant branch pipelines in parallel, wherein the multiple refrigerant branch pipelines are respectively connected to M air-cooled condensers, wherein N is a natural number greater than or equal to 2, and M is a natural number greater than or equal to 1, and the M air-cooled condensers are shared by the N refrigerant circulation flow paths; a hot water exchange water pipeline, wherein the water pipelines of the evaporators in the N refrigerant circulation flow paths arranged in positive sequence are connected in series between the head and the tail, wherein the corresponding refrigerant branch pipelines in the N refrigerant circulation flow paths arranged in reverse sequence are connected to the refrigerant inlet and outlet between the air inlet side and the air outlet side of each air-cooled condenser.

[0032] Specifically, N refrigerant circulation flow paths share M air-cooled condensers, that is, the refrigerant branch pipes arranged in each refrigerant circulation flow path are connected to M air-cooled condensers, and the arrangement order of the N refrigerant circulation flow paths between the water inlet end of the hot water exchange pipe and the water outlet end is opposite to the arrangement order between the air inlet side and the air outlet side of each air-cooled condenser. Through this design, in each air-cooled condenser, the air inlet temperature of the refrigerant in the refrigerant branch pipes in the N refrigerant circulation flow paths is different, so that the evaporation temperature of the evaporator in the refrigerant circulation flow path adjacent to the water outlet end of the hot water exchange pipe corresponds to a lower condensing temperature, thereby reducing the operating pressure ratio of the compressor in the refrigerant circulation flow path, so that the energy consumption of this part is significantly reduced, and the compressor pressure ratio in the N refrigerant circulation flow paths is balanced, thereby achieving the purpose of increasing the cooling capacity and reducing energy consumption.

[0033] In this embodiment, the interior of the evaporator is divided into a refrigerant pipeline and a water pipeline. The high-temperature water to be cooled is heat exchanged in the evaporator, and the high-temperature water in the water pipeline is cooled by the refrigerant in the refrigerant pipeline. N refrigerant circulation flow paths are sequentially arranged between the water inlet and the water outlet of the hot water exchange pipeline through the evaporator.

[0034] Optionally, when N is 2 and M is 2, the refrigerant circulation circuit includes a first refrigerant circulation circuit and a second refrigerant circulation circuit, wherein the first refrigerant circulation circuit is arranged adjacent to the water inlet end of the hot water exchange pipe, and the second refrigerant circulation circuit is arranged adjacent to the water outlet end of the hot water exchange pipe.

[0035] Optionally, the refrigerant branch pipes in the first refrigerant circulation flow circuit are respectively connected in parallel to the refrigerant inlets and outlets on the air outlet sides of the two air-cooled condensers.

[0036] Specifically, the first refrigerant circulation flow path is connected in parallel at the air outlet sides of the two air-cooled condensers through a plurality of refrigerant branch pipelines arranged in parallel; when each air-cooled condenser adopts a V-shaped fin tube structure, the first refrigerant circulation flow path is provided with four refrigerant branch pipelines in parallel, and every two refrigerant branch pipelines are sequentially connected to the refrigerant inlet and outlet ends of the V-shaped fin tube of each air-cooled condenser, and are arranged close to the air outlet side of each air-cooled condenser. When each air-cooled condenser adopts an inverted M-shaped fin tube structure, the first refrigerant circulation flow path is provided with eight refrigerant branch pipelines in parallel, and every four refrigerant branch pipelines are sequentially connected to the refrigerant inlet and outlet ends of the inverted M-shaped fin tube of each air-cooled condenser, and are arranged close to the air outlet side of each air-cooled condenser.

[0037] Optionally, the refrigerant branch pipes in the second refrigerant circulation flow circuit are respectively connected in parallel to both ends of the refrigerant inlet and outlet on the air inlet side of the two air-cooled condensers.

[0038] Specifically, the second refrigerant circulation flow path is connected in parallel at the air inlet side of the two air-cooled condensers through a plurality of refrigerant branch pipelines arranged in parallel; when each air-cooled condenser adopts a V-shaped fin tube structure, the second refrigerant circulation flow path is provided with four refrigerant branch pipelines in parallel, and every two refrigerant branch pipelines are sequentially connected to the refrigerant inlet and outlet ends of the V-shaped fin tube of each air-cooled condenser, and are arranged close to the air inlet side of each air-cooled condenser. When each air-cooled condenser adopts an inverted M-shaped fin tube structure, the first refrigerant circulation flow path is provided with eight refrigerant branch pipelines in parallel, and every four refrigerant branch pipelines are sequentially connected to the refrigerant inlet and outlet ends of the inverted M-shaped fin tube of each air-cooled condenser, and are arranged close to the air inlet side of each air-cooled condenser.

[0039] Optionally, when N is a natural number greater than 2, the refrigerant circulation flow path includes a first refrigerant circulation flow path, a second refrigerant circulation flow path to an Nth refrigerant circulation flow path, wherein the first refrigerant circulation flow path, the second refrigerant circulation flow path to the Nth refrigerant circulation flow path are arranged in sequence between the water inlet end and the end of the hot water exchange pipe.

[0040] Optionally, the refrigerant branch pipes in the first refrigerant circulation flow path, the second refrigerant circulation flow path to the Nth refrigerant circulation flow path are arranged in reverse order and connected to the refrigerant inlet and outlet between the air inlet side and the air outlet side of each air-cooled condenser.

[0041] Optionally, the refrigerants in the N refrigerant circulation circuits have the same flow direction in their respective corresponding refrigerant branch pipes.

[0042] Specifically, when the refrigerant in all refrigerant sub-pipes flows in the same direction, it can ensure that the temperature distribution in the entire system is more uniform.

[0043] In an optional embodiment of the present application, the evaporator can adopt a single-flow structure or a multi-flow structure. According to actual heat exchange requirements, pressure drop requirements, and cost factors, a single-flow, two-flow, three-flow, or even more-flow structure of the evaporator is selected to optimize the performance of the evaporator. The evaporator must be a shell and tube structure. In the best embodiment of the present application, the evaporator can adopt a full-liquid evaporator.

[0044] In addition, the single-flow structure means that the medium to be cooled (such as water) passes through the tube bundle inside the evaporator only once, that is, it enters from one end and flows out from the other end. The single-flow structure is simple, the water flow path is short, and the pressure drop is small; the three-flow structure means that the medium to be cooled passes through the tube bundle inside the evaporator three times, and multiple round trips are achieved through baffles or other flow guide devices; the three-flow structure is complex, the water flow path is long, the heat exchange area is large, the heat exchange efficiency is high, but the pressure drop is large.

[0045] In an optional embodiment of the present application, in N refrigerant circulation flow paths, if each refrigerant circulation flow path is to be connected in parallel to M air-cooled condensers, each refrigerant circulation flow path can be realized by setting O refrigerant branch pipelines. When the air-cooled condenser adopts a single fin tube structure, O is equal to M, that is, each refrigerant circulation flow path is provided with O refrigerant branch pipelines, and O refrigerant branch pipelines are sequentially connected in parallel to the single fin tubes of M air-cooled condensers. When the air-cooled condenser adopts a V-shaped fin tube structure, O is equal to 2M, that is, each refrigerant circulation flow path is provided with 2M refrigerant branch pipelines, and every two refrigerant branch pipelines are respectively connected to the refrigerant inlet and outlet ends of the V-shaped fin tube of each air-cooled condenser. When the air-cooled condenser adopts an inverted M-shaped fin tube structure, O is equal to 4M, that is, each refrigerant circulation flow path is provided with 4M refrigerant branch pipelines, and every four refrigerant branch pipelines are respectively connected to the refrigerant inlet and outlet ends of the inverted M-shaped fin tube of each air-cooled condenser.

[0046] Taking N=2, M=2, O=2 as an example, the two refrigerant circulation flow paths are respectively recorded as the first refrigerant circulation flow path and the second refrigerant circulation flow path, the two refrigerant branch pipes in the first refrigerant circulation flow path are respectively recorded as the 11th refrigerant branch pipe and the 12th refrigerant branch pipe, the two refrigerant branch pipes in the second refrigerant circulation flow path are respectively recorded as the 21st refrigerant branch pipe and the 22nd refrigerant branch pipe, and the two air-cooled condensers are respectively recorded as the first air-cooled condenser and the second air-cooled condenser. At this time, the first air-cooled condenser and the second air-cooled condenser can adopt a single-fin tube folding arrangement structure.

[0047] In this embodiment, the first evaporator in the first refrigerant circulation circuit is arranged after the water inlet end of the hot water exchange pipe, and the high-temperature water to be cooled is cooled once through the first evaporator. The second evaporator in the second refrigerant circulation circuit is arranged before the water outlet end of the hot water exchange pipe, and the high-temperature water that has been cooled once is cooled twice through the second evaporator. In the first refrigerant circulation flow circuit, a first electronic expansion valve, a first evaporator, and a first compressor are sequentially arranged on the first refrigerant main pipeline along the direction of refrigerant circulation, and the 11th refrigerant branch pipeline and the 12th refrigerant branch pipeline are connected in parallel with the first refrigerant main pipeline, and the 11th refrigerant branch pipeline is connected to the air outlet side of the first air-cooled condenser, and the 12th refrigerant branch pipeline is connected to the air outlet side of the second air-cooled condenser. After the refrigerant is discharged through the first air-cooled condenser and the second air-cooled condenser, it circulates again through the first electronic expansion valve, the first evaporator, and the first compressor; similarly, the setting of the second refrigerant circulation flow circuit is the same as the setting principle of the first refrigerant circulation flow circuit, but the 21st refrigerant branch pipeline in the second refrigerant circulation flow circuit is connected to the air inlet side of the first air-cooled condenser, and the 22nd refrigerant branch pipeline is connected to the air inlet side of the second air-cooled condenser. When the first air-cooled condenser is in operation, its air inlet side is air with a lower ambient temperature. After absorbing heat from the refrigerant in the 21st refrigerant branch-pipe, the air temperature rises. Then, after continuing to absorb heat from the refrigerant in the 11th refrigerant branch-pipe, the air with a higher temperature is discharged through the air outlet side of the first air-cooled condenser. Similarly, when the second air-cooled condenser is in operation, its air inlet side is air with a lower ambient temperature. After absorbing heat from the refrigerant in the 22nd refrigerant branch-pipe, the air temperature rises. Then, after continuing to absorb heat from the refrigerant in the 12th refrigerant branch-pipe, the air with a higher temperature is discharged through the air outlet side of the second air-cooled condenser. Thus, the first refrigerant circulation flow path and the second refrigerant circulation flow path are connected in series at the air path of the first air-cooled condenser. At the same time, the first refrigerant circulation flow path and the second refrigerant circulation flow path are connected in series at the air path of the second air-cooled condenser. The refrigerant in the 11th refrigerant branch pipeline and the 12th refrigerant branch pipeline is condensed by the first air-cooled condenser and the second air-cooled condenser and then flows into the first evaporator, so that the system high-temperature water is cooled once; the refrigerant in the 21st refrigerant branch pipeline and the 22nd refrigerant branch pipeline is condensed by the first air-cooled condenser and the second air-cooled condenser and then flows into the second evaporator, so that the system high-temperature water that has been cooled once is cooled twice.

[0048] In the above embodiment, the evaporating temperature of the first evaporator corresponds to the condensing temperature of the two air-cooled condensers, wherein the evaporating temperature and the condensing temperature are both relatively high; the evaporating temperature of the second evaporator corresponds to the condensing temperature of the two air-cooled condensers, wherein the evaporating temperature and the condensing temperature are both relatively low, so that the operating pressure ratio of the second refrigerant circulation flow path is greatly reduced compared with the traditional air-cooling system, the cooling capacity of the second refrigerant circulation flow path will increase, and the energy consumption of the second compressor of the second refrigerant circulation flow path will be reduced.

[0049] Figure 1 This is a specific implementation diagram of the multi-head air-cooled chiller refrigeration system of the present application. Figure 1 In the specific embodiment shown, N=2, M=2, O=4 is taken as an example, and the evaporator adopts a full-liquid evaporator and the air-cooled condenser adopts a V-shaped fin tube as an example. The two refrigerant circulation flow paths are respectively recorded as the first refrigerant circulation flow path and the second refrigerant circulation flow path, the four refrigerant branch pipes in the first refrigerant circulation flow path are respectively recorded as the 11th refrigerant branch pipe, the 12th refrigerant branch pipe, the 13th refrigerant branch pipe and the 14th refrigerant branch pipe, the four refrigerant branch pipes in the second refrigerant circulation flow path are respectively recorded as the 21st refrigerant branch pipe, the 22nd refrigerant branch pipe, the 23rd refrigerant branch pipe and the 24th refrigerant branch pipe, the two air-cooled condensers are respectively recorded as the first air-cooled condenser 31 and the second air-cooled condenser 32. At this time, the first air-cooled condenser 31 and the second air-cooled condenser 32 both adopt a V-shaped fin tube structure, that is, two groups of fin tubes are arranged in a V shape, and one of the fin tubes can include two or more base tubes, that is, a multi-channel fin tube. A first electronic expansion valve 13, a first fully liquid evaporator 11 and a first compressor 12 are arranged on the first refrigerant main pipeline in the first refrigerant circulation flow path, and a second electronic expansion valve 23, a second fully liquid evaporator 21 and a second compressor 22 are arranged on the second refrigerant main pipeline in the second refrigerant circulation flow path.

[0050] A first refrigerant circulation flow path and a second refrigerant circulation flow path are arranged between the water inlet end and the water outlet end of the hot water exchange pipe, wherein the water inlet end of the hot water exchange pipe is connected to the water inlet end of the internal water pipe of the first full-liquid evaporator 11, and the water outlet end of the internal water pipe of the first full-liquid evaporator 11 is connected to the water inlet end of the internal water pipe of the second full-liquid evaporator 21 through the hot water exchange pipe, and the water outlet end of the internal water pipe of the second full-liquid evaporator 21 is the water outlet end of the hot water exchange pipe; the water inlet end of the internal water pipe of the first full-liquid evaporator 11 is generally arranged on its side, opposite to its water outlet end, and the high-temperature water to be cooled passes through the water inlet end of the internal water pipe of the first full-liquid evaporator 11 It enters its internal coil and flows out through the water outlet of the internal water pipeline of the first fully liquid evaporator 11, and enters the second fully liquid evaporator 21 for secondary cooling; the refrigerant inlet of the internal refrigerant pipeline of the first fully liquid evaporator 11 is generally arranged at its bottom, and its refrigerant outlet is generally arranged at the top. After the liquid first refrigerant is reduced in pressure by the first electronic expansion valve 13, it enters the bottom of the first fully liquid evaporator 11 and fills the entire shell of the first fully liquid evaporator 11. The first refrigerant absorbs heat inside the first fully liquid evaporator 11 and gradually evaporates into a gaseous state. The gaseous first refrigerant is discharged through the refrigerant outlet, sucked into the first compressor 12, and enters the next cycle.

[0051] In the first refrigerant circulation flow path, the first full-liquid evaporator 11 is arranged on the first refrigerant main pipeline and the hot water exchange pipeline, the refrigerant inlet of the refrigerant pipeline inside the first full-liquid evaporator 11 is connected to the first electronic expansion valve 13, the refrigerant outlet of the refrigerant pipeline inside the first full-liquid evaporator 11 is connected to the inlet of the first compressor 12, and the outlet of the first compressor 12 is connected to the first air-cooled condenser 31 and the second air-cooled condenser 32 through a plurality of refrigerant branch pipelines, wherein the 11th refrigerant branch pipeline and the 12th refrigerant branch pipeline are connected to the first air-cooled condenser 31 and the second air-cooled condenser 32. The 13th refrigerant branch pipe and the 14th refrigerant branch pipe are connected to the refrigerant inlet and outlet on the air outlet side of the two groups of fin tubes of the first air-cooled condenser 31, and the 21st refrigerant branch pipe and the 22nd refrigerant branch pipe in the second refrigerant circulation flow path are connected to the refrigerant inlet and outlet on the air inlet side of the two groups of V-shaped fin tubes of the first air-cooled condenser 31, and the 23rd refrigerant branch pipe and the 24th refrigerant branch pipe are connected to the refrigerant inlet and outlet on the air inlet side of the two groups of fin tubes of the second air-cooled condenser 32.

[0052] In the first refrigerant circulation flow path, after the first refrigerant is discharged from the first fully liquid evaporator 11, it enters the first compressor 12. The first compressor 12 compresses the low-temperature, low-pressure, gaseous first refrigerant through the operation of the motor, and then discharges the high-temperature, high-pressure, gaseous first refrigerant. At this time, the first refrigerant enters the first air-cooled condenser 31 and the second air-cooled condenser 32 respectively at the same time. After heat exchange, it is gradually cooled and finally condensed into a low-temperature, high-pressure, liquid first refrigerant. After the low-temperature, high-pressure, liquid first refrigerant is depressurized by the first electronic expansion valve 13, it enters the first fully liquid evaporator 11 and exchanges heat with the system high-temperature water. The low-temperature, low-pressure, liquid first refrigerant absorbs heat and becomes a low-temperature, low-pressure, gaseous first refrigerant, thereby completing a primary refrigeration cycle.

[0053] Similarly, the secondary refrigeration cycle of the second refrigerant circulation flow circuit has the same principle and configuration as the first refrigerant circulation flow circuit, and will not be described in detail here.

[0054] In the above embodiment, in the first-stage refrigeration cycle, the evaporation temperature of the first fully liquid evaporator 11 corresponds to the condensation temperature of the two air-cooled condensers, wherein the evaporation temperature and the condensation temperature are both relatively high; in the second-stage refrigeration cycle, the evaporation temperature of the second fully liquid evaporator 21 corresponds to the condensation temperature of the two air-cooled condensers, wherein the evaporation temperature and the condensation temperature are both relatively low, so that the operating pressure ratio of the second refrigerant circulation flow path is greatly reduced compared with the traditional air-cooling system, the cooling capacity of the second refrigerant circulation flow path will increase, and the energy consumption of the second compressor of the second refrigerant circulation flow path will be reduced.

[0055] When N=3, the three refrigerant circulation flow paths are respectively recorded as the first refrigerant circulation flow path, the second refrigerant circulation flow path and the third refrigerant circulation flow path. The first evaporator in the first refrigerant circulation flow path is arranged after the water inlet end of the hot water exchange pipe, the second evaporator in the second refrigerant circulation flow path is arranged in the middle position of the hot water exchange pipe, and the third evaporator in the third refrigerant circulation flow path is arranged before the water outlet end of the hot water exchange pipe. The refrigerant branch pipeline in the first refrigerant circulation flow path is arranged near the air outlet side of each air-cooled condenser, the refrigerant branch pipeline in the third refrigerant circulation flow path is arranged near the air inlet side of each air-cooled condenser, and the refrigerant branch pipeline in the second refrigerant circulation flow path is arranged between the air inlet side and the air outlet side of each air-cooled condenser.

[0056] Similarly, when N=4, 5, ..., the refrigerant branch pipe in the first refrigerant circulation flow circuit is arranged close to the outlet side of each air-cooled condenser, and the refrigerant branch pipe in the Nth refrigerant circulation flow circuit is arranged close to the inlet side of each air-cooled condenser, that is, the refrigerant branch pipes in the Nth, N-1, N-2, ..., 2, 1 refrigerant circulation flow circuits are connected in sequence on the air path from the inlet side to the outlet side of each air-cooled condenser.

[0057] Similarly, no matter whether the air-cooled condenser adopts V-shaped fin tubes or inverted M-shaped fin tubes, the fin tubes arranged in V-shape or inverted M-shape have an air outlet side and an air inlet side. No matter how large the natural number N is, the refrigerant branch pipeline in the refrigerant circulation flow path is arranged closer to the water outlet end of the hot water exchange pipeline, and the refrigerant branch pipeline is arranged closer to the air inlet side of each air-cooled condenser.

[0058] When multiple refrigerant circulation paths use their respective corresponding air-cooled condensers to form separate circulation loops, the air inlet temperatures of the air-cooled condensers of the multiple refrigerant circulation paths are the same, but their air outlet temperatures are slightly different. This will cause the compressor of the refrigerant circulation path that is set closer to the water outlet of the hot water pipe to have a larger operating pressure ratio and greater operating energy consumption. Therefore, multiple refrigerant circulation paths need to use multiple air-cooled condensers at the same time to reduce the difference in air outlet temperatures.

[0059] On the other hand, the present application also provides a refrigeration device, which includes any one of the multi-head air-cooled chiller refrigeration systems described above.

[0060] Specifically, the refrigeration equipment is not limited to small or large chillers, household air conditioners, industrial cooling systems and the like, nor is it limited to application areas such as hospitals, scientific research institutions, office buildings, and production plants.

[0061] In summary, the present application provides a multi-head air-cooled chiller refrigeration system and refrigeration equipment. In the multi-head air-cooled chiller refrigeration system, the refrigerant sub-pipeline in the refrigerant circulation flow path arranged closer to the water outlet end of the hot water exchange pipe is arranged closer to the air inlet side of each air-cooled condenser, so that the temperature of the refrigerant in the refrigerant sub-pipeline in each refrigerant circulation flow path is different, so that the compressor pressure ratio in the multiple refrigerant circulation flow paths is balanced, thereby achieving the purpose of increasing the cooling capacity of the refrigerant circulation flow path arranged closer to the water outlet of the hot water exchange pipe and reducing its energy consumption.

[0062] Unless otherwise defined, all technical and scientific terms used in this application are the same as those generally understood by those skilled in the art to which this application belongs. If there is any inconsistency, the meaning described in the full text of this application or the meaning derived from the content recorded in the full text of this application shall prevail. In addition, the terms used in this description are only for the purpose of describing the embodiments of the present application and are not intended to limit the present application.

[0063] Note that the above are only preferred embodiments of the present application and the technical principles used. Those skilled in the art will understand that the present application is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the present application. Therefore, although the present application is described in more detail through the above embodiments, the present application is not limited to the above embodiments, and may also include more other equivalent embodiments without departing from the technical concept of the present application, all of which belong to the protection scope of the present application.

[0064] It should be noted that, in the description herein, the terms "middle", "front", "back", "top", "bottom", "left", "right", "vertical", "horizontal", "inside", "outside", etc., indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0065] In addition, the terms "installed", "set", "connected", "connected", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements or components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0066] The above description is only an embodiment of the present application and does not limit the patent scope of the present application. Any equivalent structural transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A multi-head air-cooled chiller refrigeration system, characterized in that: include: N refrigerant circulation flow paths, each of which comprises: a refrigerant main pipeline, a refrigerant pipeline with an electronic expansion valve and an evaporator connected in series between the head and the tail of the refrigerant main pipeline, a compressor, and a plurality of refrigerant branch pipelines connected in parallel, wherein the plurality of refrigerant branch pipelines are respectively connected to M air-cooled condensers, wherein N is a natural number greater than or equal to 2, M is a natural number greater than or equal to 1, and the M air-cooled condensers are shared by the N refrigerant circulation flow paths; The hot water exchange pipeline has water pipelines of the evaporator in N refrigerant circulation circuits arranged in positive sequence connected in series between the head and the tail, wherein the corresponding refrigerant branch pipelines in N refrigerant circulation circuits arranged in reverse sequence are connected to the refrigerant inlet and outlet between the air inlet side and the air outlet side of each air-cooled condenser.

2. The multi-head air-cooled chiller refrigeration system according to claim 1, characterized in that: include: When N is 2 and M is 2, the refrigerant circulation flow path includes a first refrigerant circulation flow path and a second refrigerant circulation flow path, wherein the first refrigerant circulation flow path is arranged adjacent to the water inlet end of the hot water exchange pipe, and the second refrigerant circulation flow path is arranged adjacent to the water outlet end of the hot water exchange pipe.

3. The multi-head air-cooled chiller refrigeration system according to claim 2, characterized in that: The refrigerant branch pipes in the first refrigerant circulation flow path are respectively connected in parallel to the refrigerant inlets and outlets on the air outlet sides of the two air-cooled condensers.

4. The multi-head air-cooled chiller refrigeration system according to claim 3, characterized in that: The refrigerant branch pipes in the second refrigerant circulation flow path are respectively connected in parallel to the refrigerant inlet and outlet of the air inlet side of the two air-cooled condensers.

5. The multi-head air-cooled chiller refrigeration system according to claim 1, characterized in that: Also includes: When N is a natural number greater than 2, the refrigerant circulation flow path includes a first refrigerant circulation flow path, a second refrigerant circulation flow path to an Nth refrigerant circulation flow path, wherein the first refrigerant circulation flow path, the second refrigerant circulation flow path to the Nth refrigerant circulation flow path are arranged in sequence between the water inlet end and the water outlet end of the hot water exchange pipe.

6. The multi-head air-cooled chiller refrigeration system according to claim 5, characterized in that: The refrigerant branch pipes in the first refrigerant circulation flow path, the second refrigerant circulation flow path to the Nth refrigerant circulation flow path are arranged in reverse order and connected to the refrigerant inlet and outlet between the air inlet side and the air outlet side of each air-cooled condenser.

7. The multi-head air-cooled chiller refrigeration system according to claim 1, characterized in that: The refrigerants in the N refrigerant circulation flow paths have the same flow direction in their corresponding refrigerant branch pipes.

8. A refrigeration device, characterized in that: A refrigeration system comprising a multi-head air-cooled chiller as described in any one of claims 1 to 7.

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