MULTI-COMPRESSOR ONE-PASS SEGMENTED COMPRESSION TYPE WATER CHILLER

Abstract

 The present invention discloses a multi-head single-pass sectional compression water chilling unit comprising a combined condenser and a combined evaporator, wherein the combined condenser is formed by sequentially connecting and combining a plurality of sectional condensers, the combined condenser is internally provided with a condenser tube bundle for use by all the sectional condensers, the combined evaporator is formed by sequentially connecting and combining a plurality of sectional evaporators, the combined evaporator is internally provided with an evaporator tube bundle for use by all the sectional evaporators, the sectional condensers and the sectional evaporators are in one-to-one correspondence, a compressor is connected between the sectional condenser and the sectional evaporator corresponding to each other, and the compressor, the sectional condenser and the sectional evaporator form a refrigeration function section. According to the present invention, both refrigerating capacity and chilled water flow can be independently controlled according to actual demands, which solves the problem that the refrigerating capacity and the chilled water flow of the existing water chilling unit are difficult to match, so that the good use effect of the water chilling unit is ensured.

Description

TECHNICAL FIELD

[0001] The present invention relates to the technical field of a water chilling unit, in particular to a multi-head single-pass sectional compression water chilling unit.

BACKGROUND

[0002] The existing water chilling units all take refrigerating capacity as a primary parameter, and then determine rated chilled water flow by rated supply and return water temperature. The refrigerating capacity and the chilled water flow of the water chilling units are in a relatively fixed relation, and the chilled water flow is not determined according to the flow required by a terminal of a project. In operation of the water chilling units, the condition that the refrigerating capacity is not matched with the chilled water flow often occurs. Specifically, under a certain load condition, the refrigerating capacity of a single water chilling unit can meet the demand of the refrigerating capacity at the terminal, while the flow provided by the water chilling unit cannot meet the demand of the flow at the terminal. Since chilled water is a carrier of the refrigerating capacity, insufficient chilled water flow means that there is no refrigerating capacity in certain areas, leading to lack of comfort effect. In this case, since a single water chilling unit can already meet the demand of refrigerating capacity, the water chilling units are in a low-load condition with low efficiency when the number of the water chilling units is increased, and the operation efficiency is low; if the number of the water chilling units is not increased, the output of the water pump is generally increased, and the water chilling unit provides chilled water with a flow rate larger than the rated flow rate by larger lift loss, which causes that the flow rate of the chilled water in the water chilling units is too high, and the operation efficiency is also reduced. In the operation process, the flow of chilled water in the water chilling unit is in a condition of not matching with the refrigerating capacity in most of time, which causes that the efficiency of the water chilling unit is always in a low state.

[0003] Therefore, a new technical scheme is required to solve the above problem.

SUMMARY

[0004] Objective: in order to solve the problem of difficult matching between the refrigerating capacity and the chilled water flow of the water chilling unit in the prior art, the present invention provides a multi-head single-pass sectional compression water chilling unit, which can realize the independent matching combination of the refrigerating capacity and the chilled water flow, and meet the use demands of the refrigerating capacity and the chilled water flow, thus improving the use effect of the water chilling unit.

[0005] Technical scheme: in order to achieve the above purpose, the present invention discloses a multi-head single-pass sectional compression water chilling unit comprising a combined condenser and a combined evaporator, wherein the combined condenser is formed by sequentially connecting and combining a plurality of sectional condensers, the combined condenser is internally provided with a condenser tube bundle for use by all the sectional condensers, the combined evaporator is formed by sequentially connecting and combining a plurality of sectional evaporators, the combined evaporator is internally provided with an evaporator tube bundle for use by all the sectional evaporators, the sectional condensers and the sectional evaporators are in one-to-one correspondence, a compressor is connected between the sectional condenser and the sectional evaporator corresponding to each other, and the compressor, the sectional condenser and the sectional evaporator form a refrigeration function section.

[0006] Further, the refrigeration function section further comprises a throttling device, wherein the throttling device is connected with the sectional condenser and the sectional evaporator, and the throttling device is a pressure reducing device of the water chilling unit between the condenser and the evaporator.

[0007] Further, two ends of the combined condenser are provided with a condenser inlet and a condenser outlet, two ends of the combined evaporator are provided with an evaporator inlet and an evaporator outlet, and the condenser outlet and the evaporator inlet are located on the same side, such that cooling water in the condenser and chilled water in the evaporator can run in a convection mode, thus improving the operation efficiency.

[0008] Further, the compressor are each selected from a centrifugal compressor, a magnetic levitation compressor and a screw compressor for use in combination, and the specific combination can be selected according to the demand of refrigeration conditions, such that the overall power of the compressor meets the refrigeration requirements and the refrigeration effect is ensured.

[0009] The design principle of the present invention is as follows: the overall structure of the condenser and the overall structure of the evaporator are designed into a sectional structure, a plurality of refrigeration function sections which can independently operate are formed by arranging the compressor and the throttling device, and the number of the refrigeration function sections can be correspondingly selected for operation according to the demand of refrigerating capacity, thereby ensuring that each compressor in the operation process is in a high-efficient state under the condition of providing the corresponding refrigerating capacity. Meanwhile, all the sectional condensers share one condenser tube bundle and all the sectional evaporators share one evaporator tube bundle, so that the refrigerating capacity and the chilled water flow are independent from each other; a proper evaporator tube bundle and a proper condenser tube bundle can be selected according to actual demand of the chilled water flow, and the sufficient chilled water flow can be provided all the time regardless of the number and operating states of the refrigeration function sections.

[0010] According to the load demands and device parameters of a system at the terminal of the project, the present invention calculates and determines a proper chilled water flow, so that a refrigeration pump can keep the sufficient chilled water flow at the terminal with lower energy consumption, and the chilled water, as a carrier of the refrigerating capacity, can be continuously and fully distributed in all areas at the terminal of the project.

[0011] The present invention designs and selects the power or the form of the compressor (such as the centrifugal compressor, the magnetic levitation compressor and the screw compressor) for use in combination according to conditions of the design cold loads, the function industries (such as hospitals, markets and office buildings), the climate zones (such as a cold zone, a hot-summer and cold-winter zone and a hot-summer and warm-winter zone) and the like of the project.

[0012] Beneficial effects: compared with the prior art, the present invention has the following advantages:

1. Both refrigerating capacity and chilled water flow can be independently controlled according to actual demands, which solves the problem that the refrigerating capacity and the chilled water flow of the existing water chilling unit are difficult to match, so that the good use effect of the water chilling unit is ensured, and the use comfort is improved.

2. The number of the refrigeration function sections can be selected for operation according to the actual demand of refrigerating capacity, which ensures that each compressor in the operation process is in a high-efficient state under the condition of providing the required refrigerating capacity, and thereby the operation efficiency of the water chilling unit is improved.

BRIEF DESCRIPTION OF THE DRAWING

[0013] FIG. 1 is a schematic diagram of the structure of the present invention.

DETAILED DESCRIPTION

[0014] The present invention is further illustrated by the following detailed embodiments in conjunction with the accompanying drawing, and it should be understood that these embodiments are provided only for illustrating the present invention rather than limiting the scope of the present invention, and that various equivalent modifications of the present invention by those skilled in the art after reading the present invention all fall within the scope defined by the appended claims of the present invention.

Embodiment 1

[0015] As shown in FIG. 1, the present embodiment provides a multi-head single-pass sectional compression water chilling unit comprising a combined condenser 7 and a combined evaporator 8, wherein the combined condenser 7 is formed by sequentially connecting and combining four sectional condensers, two ends of the combined condenser 7 are provided with a condenser inlet 51 and a condenser outlet 52, the four sectional condensers from the condenser inlet 51 to the condenser outlet 52 are a first sectional condenser 11, a second sectional condenser 21, a third sectional condenser 31 and a fourth sectional condenser 41, and the combined condenser 7 is internally provided with a condenser tube bundle 1 for joint use by the four sectional condensers; the combined evaporator 8 is formed by sequentially connecting and combining four sectional evaporators, two ends of the combined evaporator 8 are provided with an evaporator inlet 61 and an evaporator outlet 62, the four sectional evaporators from the evaporator outlet 62 to the evaporator inlet 61 are a first sectional evaporator 21, a second sectional evaporator 22, a third sectional evaporator 23 and a fourth sectional evaporator 24, the combined evaporator 8 is internally provided with an evaporator tube bundle 2 for joint use by the four sectional evaporators, and the condenser outlet 52 and the evaporator inlet 61 are located on the same side.

[0016] In the present embodiment, a first compressor 31 and a first throttling device 41 are connected between the first sectional condenser 11 and the first sectional evaporator 21 through pipelines, so as to form a first refrigeration function section; a second compressor 32 and a second throttling device 42 are connected between the second sectional condenser 21 and the second sectional evaporator 22 through pipelines, so as to form a second refrigeration function section; a third compressor 33 and a third throttling device 43 are connected between the third sectional condenser 31 and the third sectional evaporator 23 through pipelines, so as to form a third refrigeration function section; a fourth compressor 34 and a fourth throttling device 44 are connected between the fourth sectional condenser 41 and the fourth sectional evaporator 24 through pipelines, so as to form a fourth refrigeration function section.

[0017] In the present embodiment, the first compressor 31, the second compressor 32, the third compressor 33 and the fourth compressor 34 are a magnetic levitation compressor, a centrifugal compressor, a centrifugal compressor and a centrifugal compressor, respectively; the magnetic levitation compressor or the centrifugal compressors can be selected to be turned on according to actual conditions, and when the cold load is low and environmental conditions are favorable for the high-efficient operation of the magnetic levitation compressor, the magnetic levitation compressor is preferentially turned on to operate through an automatic control system of the water chilling unit; when the cold load is high and the environmental condition is favorable for the high-efficient operation of the centrifugal compressors, the centrifugal compressors are preferentially turned on to operate through the automatic control system of the water chilling unit.

[0018] Therefore, the whole power of the compressor can be matched with the cold load under different cold load conditions, so that the refrigerating capacity can be more accurately controlled.

Embodiment 2

[0019] In the present embodiment, the water chilling unit provided in embodiment 1 is applied as an example; specifically, the lengths of the condenser tube bundle 1 and the evaporator tube bundle 2 in the water chilling unit in embodiment 1, that is, the number of the refrigeration function sections are determined according to the actual demand of the chilled water flow, and in the present embodiment, four refrigeration function sections are selected.

[0020] The water chilling unit is operated in the following four conditions according to the demand of the refrigerating capacity at the terminal:
Condition 1: when the cold load is not more than 25% of the rated refrigerating capacity of the water chilling unit, only a first refrigeration function section (or one of the other three refrigeration function sections) is selected for operation, cooling water enters the condenser tube bundle 1 from the condenser inlet 51 and 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.

[0021] When the first refrigeration function section is in the process of operation, the first compressor 31 is operated in high-efficient state, and the first refrigeration function section produces corresponding refrigerating capacity, so as to meet refrigerating capacity demand at the terminal; in addition, the flow of the chilled water produced in the evaporator tube bundle 2 also can meet demand at the terminal.

[0022] Condition 2: when the cold load is more than 25% and not more than 50% of the rated refrigerating capacity of the water chilling unit, a first refrigeration function section and a second refrigeration function section (two of the four refrigeration function sections) are selected for operation, the operation processes of cooling water and chilled water in the condition 2 are the same as in the condition 1, the first refrigeration function section and the second refrigeration function section operate simultaneously to produce corresponding refrigerating capacity, so as to meet refrigerating capacity demand at the terminal; in addition, the flow of the chilled water produced in the evaporator tube bundle 2 also can meet demand at the terminal.

[0023] Condition 3: when the cold load is more than 50% and not more than 75% of the rated refrigerating capacity of the water chilling unit, 3 of the four refrigeration function sections are operated to produce corresponding refrigerating capacity, so as to meet refrigerating capacity demand at the terminal; in addition, the flow of the chilled water produced in the evaporator tube bundle 2 also can meet demand at the terminal. Condition 4: when the cold load is more than 75% of the rated refrigerating capacity of the water chilling unit, the four refrigeration function sections are operated simultaneously to produce corresponding refrigerating capacity, so as to meet refrigerating capacity demand at the terminal; in addition, the flow of the of the chilled water produced in the evaporator tube bundle 2 also can meet demand at the terminal.

[0024] According to above contents of the embodiment, the multi-head single-pass sectional compression water chilling unit provided by the present invention not only can meet and adapt to the demand of changing refrigerating capacity, but also can keep providing sufficient chilled water flow, thus ensuring good and stable use effect of the water chilling unit and bringing good user experience effect. In addition to realizing the above advantages, the water chilling unit also ensures that the compressors in the operation process are always in a high-efficient state, so that the overall operation efficiency of the water chilling unit is improved.

Claims

1. A multi-head single-pass sectional compression water chilling unit, characterized in that, the multi-head single-pass sectional compression water chilling unit comprises a combined condenser and a combined evaporator, wherein the combined condenser is formed by sequentially connecting and combining a plurality of sectional condensers, the combined condenser is internally provided with a condenser tube bundle for use by all the sectional condensers, the combined evaporator is formed by sequentially connecting and combining a plurality of sectional evaporators, the combined evaporator is internally provided with an evaporator tube bundle for use by all the sectional evaporators, the sectional condensers and the sectional evaporators are in one-to-one correspondence, a compressor is connected between the sectional condenser and the sectional evaporator corresponding to each other, and the compressor, the sectional condenser and the sectional evaporator form a refrigeration function section.

2. The multi-head single-pass sectional compression water chilling unit according to claim 1, characterized in that, the refrigeration function section further comprises a throttling device, and the throttling device is connected with the sectional condenser and the sectional evaporator.

3. The multi-head single-pass sectional compression water chilling unit according to claim 1, characterized in that, two ends of the combined condenser are provided with a condenser inlet and a condenser outlet, two ends of the combined evaporator are provided with an evaporator inlet and an evaporator outlet, and the condenser outlet and the evaporator inlet are located on the same side.

4. The multi-head single-pass sectional compression water chilling unit according to claim 1, characterized in that, the compressors are each selected from a centrifugal compressor, a magnetic levitation compressor and a screw compressor for use in combination.

Drawing