CN218955225U - Centrifugal heat pump unit and centrifugal water chilling unit - Google Patents
Centrifugal heat pump unit and centrifugal water chilling unit Download PDFInfo
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- CN218955225U CN218955225U CN202222875856.6U CN202222875856U CN218955225U CN 218955225 U CN218955225 U CN 218955225U CN 202222875856 U CN202222875856 U CN 202222875856U CN 218955225 U CN218955225 U CN 218955225U
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
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Abstract
The utility model discloses a centrifugal heat pump unit and a centrifugal water chilling unit, which comprise a first centrifugal compressor, a second centrifugal compressor, a condenser, a first economizer, a second economizer and an evaporator, wherein an exhaust port of the first centrifugal compressor is connected with the second centrifugal compressor, the second branch is connected with the condenser, the condenser is connected with a third branch and a fourth branch, the third branch is connected with the first economizer, the first economizer is connected with the second centrifugal compressor, the first economizer is connected with the second economizer, the fourth branch is connected with the second economizer, the second economizer is connected with the first centrifugal compressor, and the evaporator is connected with the first centrifugal compressor. The system can meet the working condition of ultrahigh pressure ratio and can also consider the working condition of conventional pressure ratio, and meanwhile, the unit can be ensured to operate efficiently and stably under the two working conditions.
Description
Technical Field
The utility model is used in the field of water chilling units, and particularly relates to a centrifugal heat pump unit and a centrifugal water chilling unit.
Background
In recent years, the refrigeration industry rapidly develops, and the market weight of water chilling units, particularly centrifugal water chilling units, is gradually increased. From the aspect of product characteristics, the centrifugal water chilling unit has the advantages of high efficiency, energy conservation and extremely strong adaptability, and can be used for civilian use, commercial use and industry. From the application scope, the centrifugal water chilling unit can be used at high temperature, medium temperature and low Wen Duogong condition. However, in the prior art, the centrifugal water chiller still has the following disadvantages, particularly under the ultra-high pressure ratio working condition.
The higher the compression ratio, the higher the demand for the centrifugal compressor. In order to increase the compression ratio, centrifugal compressors generally employ a method of increasing the rotational speed. According to the number of centrifugal compressor impellers: a centrifugal compressor having only one impeller is called a single-stage centrifugal compressor, and is limited by this type of compressor structure, and generally can only correspond to a lower compression ratio condition, so that it is mostly used in a conventional refrigeration condition. And the centrifugal compressor with two impellers is called a two-stage centrifugal compressor, and because the two-stage compression is adopted, the centrifugal compressor can meet the application of a part of working conditions with high compression ratio, and is mostly used for the working conditions with high pressure ratio of the conventional low-temperature ice storage or high-temperature heat pump. However, when the pressure ratio of the two-stage centrifugal compressor is increased to a certain value due to the existence of the clearance volume of the compressor under the working condition of the ultrahigh pressure ratio which requires both low-temperature ice storage and high-temperature heat pump, the capacity coefficient of the compressor becomes zero, the compressor does not suck air any more, the refrigerating capacity is reduced, the power consumption is increased, the refrigerating coefficient is reduced, the economical efficiency is reduced and the like, and the compressor is seriously damaged along with the occurrence of surge, so that the two-stage centrifugal compressor cannot be adopted under the working condition of the ultrahigh pressure ratio. The centrifugal compressor with three or more impellers is called a multistage centrifugal compressor, the compression ratio range which can be corresponding to the compressor is large, and the requirement of the working condition of ultra-high pressure ratio can be met.
Secondly, in some special occasions, customers need the working condition with ultrahigh pressure ratio and the working condition with normal pressure ratio, and the flexibility of adopting the single-head centrifugal water chilling unit is insufficient, so that the problems of low efficiency of the compressor after working condition switching and low efficiency and energy saving of the unit exist.
Disclosure of Invention
The utility model aims to at least solve one of the technical problems in the prior art, and provides a centrifugal heat pump unit and a centrifugal water chilling unit, which can meet the working condition of ultrahigh pressure ratio and the working condition of normal pressure ratio, and simultaneously ensure that the unit can efficiently and stably operate under the two working conditions, so that the unit has wider operating range and more adaptation places.
The technical scheme adopted for solving the technical problems is as follows:
in a first aspect, a centrifugal heat pump unit includes a first centrifugal compressor, a second centrifugal compressor, a condenser, a first economizer, a second economizer, and an evaporator, where the first centrifugal compressor has a primary impeller and a secondary impeller to form a secondary compression, the second centrifugal compressor has a tertiary impeller and a quaternary impeller to form a secondary compression, an exhaust port of the first centrifugal compressor is connected to a first compressor exhaust pipe, the first compressor exhaust pipe branches off a first branch and a second branch, the first branch is connected to an air intake of the second centrifugal compressor, the second branch is connected to the condenser, the first branch is provided with a first exhaust valve, the second branch is provided with a second exhaust valve, an exhaust port of the second centrifugal compressor is connected to a second compressor exhaust pipe, the second compressor exhaust pipe is connected to the condenser, the condenser is connected to a condenser outlet pipe, the condenser outlet pipe branches off a third branch and a fourth branch, the third branch is provided with a first valve and a second branch is connected to the second economizer, the second economizer is connected to the second economizer, the evaporator is connected to the suction port of the first centrifugal compressor through a third muffler.
With reference to the first aspect, in certain implementation manners of the first aspect, a first air return valve is disposed on the first air return pipe.
With reference to the first aspect and the foregoing implementation manner, in some implementation manners of the first aspect, a second air return valve is disposed on the second air return pipe.
With reference to the first aspect and the foregoing implementation manner, in certain implementation manners of the first aspect, a third economizer is further included, the third economizer is disposed between the first economizer and the second economizer, a liquid outlet pipe of the first economizer is provided with a fourth throttling expansion valve and is connected to the third economizer, the third economizer is connected to an air suction port of the second centrifugal compressor through a fourth air return pipe, and the liquid outlet pipe of the third economizer is connected to the fourth branch before the second throttling expansion valve.
With reference to the first aspect and the foregoing implementation manner, in some implementation manners of the first aspect, a third air return valve is disposed on the fourth air return pipe.
With reference to the first aspect and the foregoing implementation manner, in some implementation manners of the first aspect, a third liquid outlet valve is disposed on a liquid outlet pipe of the third economizer.
With reference to the first aspect and the foregoing implementation manners, in certain implementation manners of the first aspect, a primary impeller and a secondary impeller of the first centrifugal compressor are coaxially connected.
With reference to the first aspect and the foregoing implementation manners, in certain implementation manners of the first aspect, the third-stage impeller and the fourth-stage impeller of the second centrifugal compressor are coaxially connected.
With reference to the first aspect and the foregoing implementation manner, in certain implementation manners of the first aspect, a condenser liquid storage tank is disposed at a bottom of the condenser, and the condenser liquid outlet pipe is connected to the condenser liquid storage tank.
In a second aspect, a centrifugal chiller includes a first heat exchange water tank, a second heat exchange water tank, and a centrifugal heat pump unit according to any one of the first aspect, the condenser is disposed in the first heat exchange water tank, and the evaporator is disposed in the second heat exchange water tank.
One of the above technical solutions has at least one of the following advantages or beneficial effects:
according to the technical scheme, the heat pump unit can operate in an ultrahigh pressure ratio mode and a conventional pressure ratio mode, and when the heat pump unit operates in the ultrahigh pressure ratio mode, the first centrifugal compressor and the second centrifugal compressor are operated in series to form complementation, and meanwhile the heat pump unit is used in a throttling mode by being matched with the first economizer, the second economizer and the throttling expansion valve, so that the heat pump unit is more reliable, more efficient and more energy-saving when the ultrahigh pressure ratio working condition is met.
When the user only needs the normal pressure ratio working condition, the unit can be switched into the normal pressure ratio mode, at the moment, the unit only starts the first centrifugal compressor, and the second centrifugal compressor stops running, so that the unit runs according to the single-head two-stage compression centrifugal chiller unit mode, the running of the whole system is more matched with the normal pressure ratio working condition, the efficiency of the compressor is high, and the unit is continuous and efficient.
Through the switching of the operation modes, the unit can be operated more flexibly under different pressure ratio working conditions, the operation range is wider, and the energy is saved. The system can meet the working condition of ultrahigh pressure ratio and can also consider the working condition of conventional pressure ratio, and meanwhile, the system can be ensured to operate efficiently and stably under two working conditions, so that the system has wider operating range and is suitable for more places.
Additional aspects and advantages of the utility model will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the utility model.
Drawings
The foregoing and/or additional aspects and advantages of the utility model will become apparent and may be better understood from the following description of embodiments taken in conjunction with the accompanying drawings in which:
FIG. 1 is a schematic diagram of one embodiment of the present utility model operating in an ultra-high pressure ratio mode;
FIG. 2 is a schematic diagram of one embodiment of the conventional pressure ratio mode operation shown in FIG. 1.
Detailed Description
Reference will now be made in detail to the present embodiments of the present utility model, examples of which are illustrated in the accompanying drawings, wherein the accompanying drawings are used to supplement the description of the written description so that one can intuitively and intuitively understand each technical feature and overall technical scheme of the present utility model, but not to limit the scope of the present utility model.
In the present utility model, if directions (up, down, left, right, front and rear) are described, they are merely for convenience of description of the technical solution of the present utility model, and do not indicate or imply that the technical features must be in a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present utility model.
In the present utility model, "a plurality of" means one or more, and "a plurality of" means two or more, and "greater than", "less than", "exceeding", etc. are understood to not include the present number; "above", "below", "within" and the like are understood to include this number. In the description of the present utility model, the description of "first" and "second" if any is used solely for the purpose of distinguishing between technical features and not necessarily for the purpose of indicating or implying a relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.
In the present utility model, unless clearly defined otherwise, terms such as "disposed," "mounted," "connected," and the like should be construed broadly and may be connected directly or indirectly through an intermediate medium, for example; the connecting device can be fixedly connected, detachably connected and integrally formed; can be mechanically connected, electrically connected or capable of communicating with each other; may be a communication between two elements or an interaction between two elements. The specific meaning of the words in the utility model can be reasonably determined by a person skilled in the art in combination with the specific content of the technical solution.
Referring to fig. 1 and 2, an embodiment of the present utility model provides a centrifugal heat pump unit including a first centrifugal compressor 1, a second centrifugal compressor 2, a condenser 3, a first economizer 5, a second economizer 7, and an evaporator 4, the first centrifugal compressor 1, the second centrifugal compressor 2, the condenser 3, the first economizer 5, the second economizer 7, and the evaporator 4 constituting a closed refrigerant refrigeration cycle.
Specifically, referring to fig. 1 and 2, the first centrifugal compressor 1 has a first-stage impeller and a second-stage impeller to form a second-stage compression, the second centrifugal compressor 2 has a third-stage impeller and a fourth-stage impeller to form a second-stage compression, an exhaust port of the first centrifugal compressor 1 is connected with a first compressor exhaust pipe 22, the first compressor exhaust pipe 22 is separated into a first branch and a second branch, the first branch is connected with an air suction port of the second centrifugal compressor 2, the second branch is connected with the condenser 3, a first exhaust valve 13 is arranged on the first branch, a second exhaust valve 14 is arranged on the second branch, and the second branch is used for shorting the second centrifugal compressor 2 and realizing switching of two different operation modes in cooperation with the first exhaust valve 13 and the second exhaust valve 14. The exhaust port of the second centrifugal compressor 2 is connected with a second compressor exhaust pipe 23, the second compressor exhaust pipe 23 is connected with the condenser 3, the condenser 3 is connected with a condenser liquid outlet pipe 24, the condenser liquid outlet pipe 24 is connected with a third branch and a fourth branch, a first liquid outlet valve 15 and a first throttle expansion valve 9 are arranged on the third branch, the third branch is connected with the first economizer 5, the first economizer 5 is connected with an inter-stage return port of the second centrifugal compressor 2 through a first return air pipe 25 and is used for guiding refrigerant between a three-stage impeller and a four-stage impeller through the inter-stage return air port, the liquid outlet pipe of the first economizer 5 is directly or indirectly connected with the second economizer 7, the fourth branch is provided with a second liquid outlet valve 16 and a second throttle expansion valve 11, the fourth branch is connected with the second economizer 7, the second economizer 7 is connected with an inter-stage return air port of the first centrifugal compressor 1 through a second return air pipe 27 and is used for guiding the refrigerant between the first-stage impeller and the second-stage impeller, the liquid outlet pipe of the second economizer 7 is provided with a third throttle expansion valve 12 and is connected with the third evaporator 4 through the first evaporator 21 and is connected with the first centrifugal compressor 1 through the third return air inlet 21.
In the technical scheme of the utility model, the heat pump unit can operate in an ultrahigh pressure ratio mode and a conventional pressure ratio mode, when the heat pump unit operates in the ultrahigh pressure ratio mode, referring to fig. 1, the first exhaust valve 13 is opened, the second exhaust valve 14 is closed, the first liquid outlet valve 15 is opened, the second liquid outlet valve 16 is closed, the first centrifugal compressor 1 and the second centrifugal compressor 2 are operated in series, the first-stage impeller realizes the first-stage compression, the second-stage impeller realizes the second-stage compression, the third-stage impeller realizes the third-stage compression, the fourth-stage impeller realizes the fourth-stage compression, the complementation is formed, and the heat pump unit is used in a throttling way by matching with the first economizer 5, the second economizer 7 and the throttling expansion valve, and is more reliable, more efficient and more energy-saving when the ultrahigh pressure ratio working condition operation is satisfied.
When the user only needs the normal pressure ratio working condition, the unit can be switched to the normal pressure ratio mode by switching the unit, referring to fig. 2, the first exhaust valve 13 is closed, the second exhaust valve 14 is opened, the first liquid outlet valve 15 is closed, the second liquid outlet valve 16 is opened, at the moment, the unit only starts the first centrifugal compressor 1, and the second centrifugal compressor 2 stops running, so that the unit runs according to the single-unit two-stage compression centrifugal chiller unit mode, the running of the whole system is more matched with the normal pressure ratio working condition, the efficiency of the compressor is high, and the unit is continuous and efficient.
Through the switching of the operation modes, the unit can be operated more flexibly under different pressure ratio working conditions, the operation range is wider, and the energy is saved. The system can meet the working condition of ultrahigh pressure ratio and can also consider the working condition of conventional pressure ratio, and meanwhile, the system can be ensured to operate efficiently and stably under two working conditions, so that the system has wider operating range and is suitable for more places.
Referring to fig. 1 and 2, a first return air valve 17 is provided in the first return air pipe 25 to control the flow of the refrigerant from the first economizer 5 to the second centrifugal compressor 2.
Referring to fig. 1 and 2, a second return air valve 20 is provided on the second return air pipe 27 for controlling the flow back of the refrigerant from the second economizer 7 to the first centrifugal compressor 1.
In some embodiments, referring to fig. 1 and 2, the centrifugal heat pump unit further includes a third economizer 6, the third economizer 6 is disposed between the first economizer 5 and the second economizer 7, a liquid outlet pipe of the first economizer 5 is disposed with a fourth throttling expansion valve 10 and is connected to the third economizer 6, the third economizer 6 is connected to the air suction port of the second centrifugal compressor 2 through a fourth air return pipe 26, and the liquid outlet pipe of the third economizer 6 is connected to a fourth branch before the second throttling expansion valve 11. The third economizer 6 is configured to direct refrigerant between the secondary and tertiary impellers via a fourth return line 26 to further provide efficiency.
Further, referring to fig. 1 and 2, a third air return valve 18 is provided on the fourth air return pipe 26 for controlling the flow of the refrigerant from the third economizer 6 back to the second centrifugal compressor 2.
Referring to fig. 1 and 2, a third outlet valve 19 is provided on the outlet pipe of the third economizer 6.
The first air return valve 17, the second air return valve 20, the third air return valve 18, the first liquid outlet valve 15, the second liquid outlet valve 16 and the third liquid outlet valve 19 all adopt electric ball valves, and related loops are automatically closed through the electric ball valves of the system, so that the quick switching of the running modes of the system is realized.
Wherein the primary impeller and the secondary impeller of the first centrifugal compressor 1 are coaxially connected. The third-stage impeller and the fourth-stage impeller of the second centrifugal compressor 2 are coaxially connected.
Referring to fig. 1 and 2, a condenser liquid storage tank 8 is arranged at the bottom of the condenser 3, refrigerant is condensed in the condenser 3 and then collected in the condenser liquid storage tank 8, and a condenser liquid outlet pipe 24 is connected out of the condenser liquid storage tank 8.
The embodiment of the utility model also provides a centrifugal water chilling unit, which comprises a first heat exchange water tank, a second heat exchange water tank and the centrifugal heat pump unit in any embodiment, wherein the condenser 3 is arranged in the first heat exchange water tank, and the evaporator 4 is arranged in the second heat exchange water tank. The centrifugal water chilling unit is characterized in that the first heat exchange water tank can output hot water outwards, and the second heat exchange water tank can output cold water outwards.
In the description of the present specification, reference to the terms "example," "embodiment," or "some embodiments," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the utility model. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The present utility model is, of course, not limited to the above-described embodiments, and one skilled in the art can make equivalent modifications or substitutions without departing from the spirit of the utility model, and these equivalent modifications or substitutions are intended to be included in the scope of the present utility model as defined in the claims.
Claims (10)
1. The centrifugal heat pump unit is characterized by comprising a first centrifugal compressor, a second centrifugal compressor, a condenser, a first economizer, a second economizer and an evaporator, wherein the first centrifugal compressor is provided with a first-stage impeller and a second-stage impeller to form secondary compression, the second centrifugal compressor is provided with a third-stage impeller and a fourth-stage impeller to form secondary compression, an exhaust port of the first centrifugal compressor is connected with a first compressor exhaust pipe, the first compressor exhaust pipe is separated into a first branch and a second branch, the first branch is connected with an air suction port of the second centrifugal compressor, the second branch is connected with the condenser, a first exhaust valve is arranged on the first branch, a second exhaust valve is arranged on the second branch, an exhaust port of the second centrifugal compressor is connected with a second compressor exhaust pipe, the second compressor exhaust pipe is connected with the condenser, the condenser is connected with a condenser liquid outlet pipe, the condenser liquid outlet pipe is separated into a third branch and a fourth branch, the third branch is provided with a first exhaust valve and a second branch is connected with the second economizer, the second economizer is connected with the second economizer, the first economizer and the second economizer is connected with the second economizer, the evaporator is connected to the suction port of the first centrifugal compressor through a third muffler.
2. The centrifugal heat pump assembly according to claim 1, wherein the first return air pipe is provided with a first return air valve.
3. The centrifugal heat pump assembly according to claim 1, wherein the second return air pipe is provided with a second return air valve.
4. The centrifugal heat pump assembly according to claim 1, further comprising a third economizer disposed between the first economizer and the second economizer, wherein a liquid outlet pipe of the first economizer is provided with a fourth throttle expansion valve and is connected to the third economizer, wherein the third economizer is connected to the air inlet of the second centrifugal compressor through a fourth air return pipe, and wherein the liquid outlet pipe of the third economizer is connected to the fourth branch before the second throttle expansion valve.
5. The centrifugal heat pump assembly according to claim 4, wherein the fourth return air pipe is provided with a third return air valve.
6. The centrifugal heat pump assembly according to claim 4, wherein the third economizer has a third discharge valve provided in a discharge pipe thereof.
7. The centrifugal heat pump assembly of claim 1, wherein the primary impeller and the secondary impeller of the first centrifugal compressor are coaxially connected.
8. The centrifugal heat pump assembly of claim 1, wherein the third and fourth stage impellers of the second centrifugal compressor are coaxially connected.
9. The centrifugal heat pump assembly according to claim 1, wherein a condenser liquid storage tank is arranged at the bottom of the condenser, and the condenser liquid outlet pipe is connected out from the condenser liquid storage tank.
10. A centrifugal chiller, comprising a first heat exchange water tank, a second heat exchange water tank, and the centrifugal heat pump unit of any one of claims 1-9, wherein the condenser is disposed in the first heat exchange water tank, and the evaporator is disposed in the second heat exchange water tank.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202222875856.6U CN218955225U (en) | 2022-10-28 | 2022-10-28 | Centrifugal heat pump unit and centrifugal water chilling unit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202222875856.6U CN218955225U (en) | 2022-10-28 | 2022-10-28 | Centrifugal heat pump unit and centrifugal water chilling unit |
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| CN218955225U true CN218955225U (en) | 2023-05-02 |
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| CN202222875856.6U Active CN218955225U (en) | 2022-10-28 | 2022-10-28 | Centrifugal heat pump unit and centrifugal water chilling unit |
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