WO2023005155A1

WO2023005155A1 - Multi-compressor one-pass segmented compression type water chiller

Info

Publication number: WO2023005155A1
Application number: PCT/CN2022/070417
Authority: WO
Inventors: 蒋家祺; 薛中柱
Original assignee: 江苏区宇能源有限公司
Priority date: 2021-07-29
Filing date: 2022-01-06
Publication date: 2023-02-02
Also published as: CN113587467A; EP4148347A4; EP4148347A1; US20230324083A1

Abstract

A multi-compressor one-pass segmented compression type water chiller, comprising a combined condenser (7) and a combined evaporator (8). The combined condenser (7) is formed by sequentially connecting and combining a plurality of segmented condensers (11, 21, 31, 41), and a condenser tube bundle (1) is provided in the combined condenser (7) for use by all the segmented condensers (11, 21, 31, 41). The combined evaporator (8) is formed by sequentially connecting and combining a plurality of segmented evaporators (21, 22, 23, 24), and an evaporator tube bundle (2) is provided in the combined evaporator (8) for use by all the segmented evaporators (21, 22, 23, 24). The segmented condensers (11, 21, 31, 41) are in one-to-one correspondence with the segmented evaporators (21, 22, 23, 24). Compressors (31, 32, 33, 34) are connected between the segmented condensers (11, 21, 31, 41) and the segmented evaporators (21, 22, 23, 24) which correspond to each other. The compressor (31, 32, 33, 34), the segmented condensers (11, 21, 31, 41) and the segmented evaporators (21, 22, 23, 24) form a refrigeration function segment. The refrigerating capacity and the chilled water flow can both be independently controlled according to actual needs, thereby solving the problem in the existing water chillers that it is difficult to achieve matching of the refrigerating capacity and the chilled water flow.

Description

A multi-head single-return segmental compression chiller

technical field

The invention relates to the technical field of chillers, in particular to a multi-head, single-return segmental compression chiller.

Background technique

The current chillers use the cooling capacity as the primary parameter, and then determine the rated chilled water flow rate based on the rated supply and return water temperature. There is a relatively fixed relationship between the cooling capacity and the chilled water flow rate, and the chilled water flow rate is not based on It is determined by the flow rate required at the end of the project. During the operation of the chiller, the cooling capacity and the chilled water flow are often inconsistent. Specifically, under a certain load condition, the cooling capacity of a single chiller can meet the cooling capacity demand of the terminal, but the flow provided by the chiller cannot Satisfy the flow demand at the end. Because chilled water is the carrier of cold energy, insufficient chilled water flow means that there is no cold energy in some areas, and there is no comfort effect. In this case, if you increase the operation of chillers, because a single chiller can already meet the demand for cooling capacity, if you add chillers, each chiller will be in a low-efficiency low-load condition, and the operating efficiency will be low; if you do not increase the chiller, Generally, the output of the water pump is increased to make the chiller provide chilled water greater than the rated flow rate with greater head loss, but in this way, the chilled water flow rate in the chiller is too fast, and the operating efficiency will also be reduced. Therefore, during most of the running time, the chilled water flow of the chiller does not match the cooling capacity, resulting in a low efficiency of the chiller.

So a new technical solution is needed to solve this problem.

Contents of the invention

Purpose of the invention: In order to overcome the problem in the prior art that the chilled water flow and cooling capacity of the chiller are difficult to match, a multi-head single-return segmental compression chiller is provided, which can realize the cooling capacity and chilled water flow rate The respective independent matching combinations meet the requirements of cooling capacity and chilled water flow, and improve the use effect of the chiller.

Technical solution: In order to achieve the above purpose, the present invention provides a multi-head single-return segmental compression chiller, which includes a combined condenser and a combined evaporator, and the combined condenser is sequentially connected by several segmental condensers The combined condenser is equipped with a condenser tube bundle for use by all segmental condensers. The combined evaporator is composed of several segmental evaporators connected in sequence. The combined evaporator An evaporator tube bundle is provided inside for use by all segmental evaporators, the segmental condensers and segmental evaporators are in one-to-one correspondence, and a compressor is connected between the corresponding segmental condensers and segmental evaporators , the compressor, segmental condenser and segmental evaporator form a refrigeration function segment.

Further, the refrigerating functional section also includes a throttling device, the throttling device is respectively connected to the segmental condenser and the segmental evaporator, and the throttling device is a decompression device between the condenser and the evaporator of the chiller .

Further, the two ends of the combined condenser are the condenser inlet and the condenser outlet respectively, the two ends of the combined evaporator are the evaporator inlet and the evaporator outlet respectively, and the condenser outlet and the evaporator inlet are Located on the same side, the cooling water in the condenser and the chilled water in the evaporator can run convectively, which improves the operating efficiency.

Further, the compressor is combined with a centrifugal compressor, a magnetic levitation compressor, or a screw compressor. According to the requirements of refrigeration conditions, a specific combination can be selected so that the overall power of the compressor meets the refrigeration requirements. Guaranteed cooling effect.

The design principle of the present invention is: design the overall structure of the condenser and the overall structure of the evaporator into segmented structures, and through the setting of compressors and throttling devices, a plurality of refrigerating functional segments that can operate independently are formed. Demand, corresponding to the number of operation of the selected refrigeration function section, so as to ensure that each compressor participating in the operation is in an efficient operation state under the condition of providing the corresponding cooling capacity. At the same time, because all the segmental condensers share one condenser tube bundle , all segmental evaporators share one evaporator tube bank, so the cooling capacity and chilled water flow have achieved an independent relationship, and the appropriate evaporator tube bank and condenser tube bank can be selected according to the actual chilled water flow demand, regardless of the cooling function section The number and conditions of operation can always provide sufficient chilled water flow.

According to the load demand and equipment parameters of the terminal system of the project, the present invention calculates and determines the appropriate chilled water flow, so that the chilled pump can maintain sufficient chilled water flow at the end with low energy consumption, so that the chilled water can be used as the carrier of cooling capacity continuously and efficiently. Adequate distribution in all areas of the project end.

According to the design cooling load of the project, the functional formats (such as hospitals, shopping malls, office buildings and other functional formats), and the climatic regions (such as cold regions, hot summer and cold winter regions, hot summer and warm winter regions, etc.), the present invention designs Choose compressor power or form (such as centrifugal compressor, magnetic levitation compressor, or screw compressor) for combined use.

Beneficial effect: compared with the prior art, the present invention has the following advantages:

1. The cooling capacity and chilled water flow rate can be independently controlled according to actual needs, which solves the problem that the cooling capacity and chilled water flow rate of existing chillers are difficult to match, thus ensuring the use effect of the chiller unit and improving the comfort of use sex.

2. According to the actual demand of cooling capacity, the operating quantity of the cooling function section can be selected. Under the condition of ensuring the required cooling capacity, each compressor participating in the operation can be in a high-efficiency operating state, thereby improving the operating efficiency of the chiller.

Description of drawings

Fig. 1 is a structural schematic diagram of the present invention.

Detailed ways

Below in conjunction with accompanying drawing and specific embodiment, further illustrate the present invention, should be understood that these embodiments are only for illustrating the present invention and are not intended to limit the scope of the present invention, after having read the present invention, those skilled in the art will understand various aspects of the present invention Modifications in equivalent forms all fall within the scope defined by the appended claims of this application.

Example 1:

As shown in Figure 1, this embodiment provides a multi-head single-return segmental compression chiller, including a combined condenser 7 and a combined evaporator 8, and the combined condenser 7 consists of four segmental condensers in sequence The two ends of the combined condenser 7 are the condenser inlet 51 and the condenser outlet 52 respectively, and the four segmental condensers are respectively the first segmental condenser 11 from the condenser inlet 51 to the condenser outlet 52 , the second segmental condenser 21, the third segmental condenser 31 and the fourth segmental condenser 41, the combined condenser 7 is provided with a condenser tube bundle 1 for common use by four segmental condensers, combined The evaporator 8 is composed of four segmented evaporators connected sequentially. The two ends of the combined evaporator 8 are the evaporator inlet 61 and the evaporator outlet 62 respectively. The four segmented evaporators are from the evaporator outlet 62 to the evaporator. The device inlet 61 is respectively the first subsection evaporator 21, the second subsection evaporator 22, the third subsection evaporator 23 and the fourth subsection evaporator 24, and the combined evaporator 8 is provided with an evaporator tube bundle 2. For the common use of four segmented evaporators, the condenser outlet 52 and the evaporator inlet 61 are located on the same side.

In this embodiment, the first compressor 31 and the first throttling device 41 are respectively connected through pipelines between the first segment condenser 11 and the first segment evaporator 21, thus forming the first refrigeration function segment; Between the two-stage condenser 21 and the second stage evaporator 22, a second compressor 32 and a second throttling device 42 are respectively connected by pipelines, so that the second refrigeration function section is formed; the third stage condenser 31 and the third section evaporator 23 are respectively connected with the third compressor 33 and the third throttling device 43 through pipelines, thus forming the third refrigeration function section; the fourth section condenser 41 and the fourth section A fourth compressor 34 and a fourth throttling device 44 are respectively connected between the stage evaporators 24 through pipelines, thus forming a fourth refrigeration function stage.

In this embodiment, the first compressor 31, the second compressor 32, the third compressor 33 and the fourth compressor 34 are respectively a magnetic levitation compressor, a centrifugal compressor, a centrifugal compressor and a centrifugal compressor. In the actual situation, choose to start the magnetic levitation compressor or the centrifugal compressor. When the cooling load is low and the environmental conditions are conducive to the efficient operation of the magnetic levitation compressor, the automatic control system of the refrigerator will give priority to the operation of the magnetic levitation compressor; when the cooling load is high , when the environmental conditions are conducive to the efficient operation of the centrifugal compressor, the centrifugal compressor is given priority to start and run through the automatic control system of the chiller.

In this way, under different cooling load conditions, the overall power of the compressor can match the upper cooling load, so that the cooling capacity can be controlled more precisely.

Example 2:

In this embodiment, the water chiller provided in Example 1 is used as an example. First, according to the actual chilled water flow demand, the lengths of the condenser tube bundle 1 and the evaporator tube bundle 2 in the chiller in Example 1 are determined, that is, the cooling function The number of sections, four refrigeration function sections are selected in this embodiment.

During the operation of the chiller, according to the demand for terminal cooling capacity, the following conditions are met:

Situation 1: When the cooling load is not greater than 25% of the rated cooling capacity of the chiller, choose to run only the first cooling function segment (or one of the other three cooling function segments), and the cooling water enters from the condenser inlet 51 to the condenser The evaporator tube bundle 1 flows out from the condenser outlet 52 , and then the chilled water enters the evaporator tube bundle 2 from the evaporator inlet 61 and flows out from the evaporator outlet 62 .

During the operation of the first refrigeration functional section, the first compressor 31 is in an efficient operation state, and the operation of the first refrigeration functional section generates corresponding cooling capacity to meet the cooling capacity demand of the terminal. In addition, the chilled water flow generated in the evaporator tube bundle 2 It can also meet the needs of the end.

Situation 2: When the cooling load is greater than 25% and not greater than 50% of the rated cooling capacity of the chiller, choose to run the first cooling function segment and the second cooling function segment (as long as it is two of the four cooling function segments), The operation process of cooling water and chilled water is the same as in case 1. The simultaneous operation of the first refrigeration function segment and the second refrigeration function segment generates corresponding cooling capacity to meet the cooling capacity demand at the end. In addition, the chilled water generated in the evaporator tube bundle 2 The flow can also meet the needs of the terminal.

Situation 3: When the cooling load is greater than 50% and not greater than 75% of the rated cooling capacity of the chiller, run 3 of the four refrigeration function sections to generate corresponding cooling capacity to meet the cooling capacity demand at the end. In addition, the evaporator tube bundle The chilled water flow generated in 2 can also meet the demand of the terminal.

Situation 4: When the cooling load is greater than 75% of the rated refrigerating capacity of the chiller, four refrigerating functional sections are operated at the same time to generate the corresponding refrigerating capacity to meet the cooling capacity demand at the end. In addition, the chilled water flow generated in the evaporator tube bundle 2 can also be Meet the needs of the end.

According to the above content of this embodiment, it can be seen that the multi-head single-return segmental compression chiller provided by the present invention can not only meet and adapt to the changing demand for cooling capacity, but also can maintain a sufficient amount of chilled water flow to ensure that the chiller The good and stable use effect ensures a good user experience effect. In addition, on the basis of realizing the above two points, the chiller ensures that the compressors participating in the operation are always in a high-efficiency operation state during the operation process, thereby improving The overall operating efficiency of the chiller.

Claims

A multi-head single-return segmental compression chiller is characterized in that it includes a combined condenser and a combined evaporator, and the combined condenser is formed by sequentially connecting and combining several segmental condensers. Condenser tube bundles are provided in the condenser for use by all segmental condensers. The combined evaporator is composed of several segmental evaporators sequentially connected and combined. The combined evaporator is provided with evaporator tube bundles. For use with all segmental evaporators, the segmental condensers and segmental evaporators are in one-to-one correspondence, and a compressor is connected between the corresponding segmental condensers and segmental evaporators, and the compressor, segmental condensing The evaporator and the segmented evaporator form a refrigeration function segment.
A multi-head single-return segmental compression chiller according to claim 1, wherein the refrigerating functional segment further includes a throttling device, and the throttling device is respectively connected to the segmental condenser and the sub-stage condenser. section evaporator.
A multi-head single-return segmental compression chiller according to claim 1, wherein the two ends of the combined condenser are respectively the condenser inlet and the condenser outlet, and the combined evaporator The two ends of the evaporator are respectively the evaporator inlet and the evaporator outlet, and the condenser outlet and the evaporator inlet are located on the same side.
The multi-head single-return segmental compression chiller according to claim 1, wherein the compressor is combined with a centrifugal compressor, a magnetic levitation compressor, or a screw compressor.