Refrigerating system and air conditioning unit

Abstract

The utility model discloses a refrigerating system and an air conditioning unit. The refrigerating system comprises a compressor; an inlet of the condenser is connected to an exhaust port of the compressor; the at least two cold storage evaporation modules are arranged in parallel, each cold storage evaporation module comprises an evaporator and a liquid storage device connected between an inlet of the evaporator and an outlet of the condenser, and an outlet of the evaporator is connected to an air suction port of the compressor; the liquid storage devices of all the cold storage evaporation modules are communicated through balance pipes so that the liquid level heights of all the liquid storage devices can be the same. Each evaporator is provided with the liquid storage device, the liquid storage devices are communicated through the balance pipes so as to balance the liquid level height of the liquid storage devices, it is guaranteed that the flow of all the evaporators is uniform, and then stable cooling is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of refrigeration systems, and in particular to a cold storage and flow balance refrigeration system and an air conditioning unit. Background Art

[0002] With the continuous development of the industrial field and the improvement of people's requirements for environmental comfort, more and more air conditioners can provide more stable and precise temperature control, such as process air conditioners. In some applications with high requirements for the temperature control range, the refrigeration system uses multiple evaporators in parallel to provide cooling load to the terminals respectively. Due to the inconsistent circuit resistance of each parallel evaporator, the refrigerant flow through each evaporator is uneven or the cooling load demand of a terminal increases, resulting in a serious lack of cooling load at some terminals, affecting the user experience.

[0003] Therefore, how to design a refrigeration system that can achieve flow balance of parallel evaporators is a technical problem that needs to be solved urgently in the industry. Utility Model Content

[0004] In order to solve the defects of uneven refrigerant flow distribution in existing parallel evaporators with different paths, resulting in insufficient cooling capacity provided by some evaporators to the terminal load, the utility model proposes a refrigeration system and air-conditioning unit with cold storage and flow balance, in which each evaporator is equipped with a liquid reservoir, and the liquid reservoirs are connected by a balancing pipe to balance the liquid level height of the liquid reservoir, thereby ensuring uniform flow of each evaporator and achieving stable cooling.

[0005] The technical solution adopted by the utility model is to design a refrigeration system, including:

[0006] compressor;

[0007] a condenser, the inlet of which is connected to the exhaust port of the compressor;

[0008] At least two cold storage evaporation modules are arranged in parallel, the cold storage evaporation modules include an evaporator and a liquid storage tank connected between an inlet of the evaporator and an outlet of the condenser, and the outlet of the evaporator is connected to an air intake port of the compressor;

[0009] The liquid reservoirs of all the cold storage evaporation modules are connected via a balance pipe so that the liquid level height of each liquid reservoir is the same.

[0010] Furthermore, the installation height of the liquid storage devices of all the cold storage evaporation modules is the same, and the installation height of the condenser is higher than the liquid storage device.

[0011] Furthermore, a compressor bypass branch is connected between the exhaust port and the intake port of the compressor, and a compressor bypass valve is installed in the compressor bypass branch.

[0012] Furthermore, the cold storage evaporation module also includes a refrigerant pump and a refrigerant pump bypass valve arranged in parallel, and the refrigerant in the liquid storage tank is delivered to the evaporator through the refrigerant pump bypass valve or the refrigerant pump.

[0013] Furthermore, the refrigeration system can operate in at least one of a mechanical refrigeration state, a natural refrigeration state, and an emergency refrigeration state;

[0014] When operating in the mechanical refrigeration state, the compressor is turned on, the compressor bypass valve is closed, the refrigerant pump is turned off, and the refrigerant pump bypass valve is opened;

[0015] and / or when operating in a natural cooling state, the compressor is turned off, the compressor bypass valve is opened, the refrigerant pump is turned off, and the refrigerant pump bypass valve is opened;

[0016] And / or when operating in an emergency refrigeration state, the compressor is turned off, the compressor bypass valve is opened, the refrigerant pump is turned on, and the refrigerant pump bypass valve is closed.

[0017] Furthermore, the cold storage evaporation module also includes an air collecting pipe, a liquid distribution pipe, and at least one fan. The evaporator has multiple evaporation tubes, the top of the evaporation tube is connected to the air collecting pipe, and the bottom is connected to the liquid distribution pipe; wherein, the exhaust port of the air collecting pipe is connected to the air intake port of the compressor, one end of the liquid distribution pipe is connected to the refrigerant pump bypass valve, and the other end is connected to the refrigerant pump, and the fan drives the airflow through the evaporation tube.

[0018] Furthermore, the evaporator, liquid storage tank, refrigerant pump, refrigerant pump bypass valve, gas collecting pipe, liquid distribution pipe, and fan of the cold storage evaporation module are assembled to form an integrated device.

[0019] Furthermore, the refrigerant pump is a variable frequency pump with adjustable speed.

[0020] In some embodiments, the condenser is an evaporative condenser.

[0021] The utility model also provides an air conditioning unit, which comprises the above-mentioned refrigeration system.

[0022] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0023] 1. Each evaporator is equipped with a liquid reservoir, which is connected by a balance pipe to balance the liquid level of the reservoir, ensuring uniform flow of each evaporator and achieving stable cooling;

[0024] 2. The installation height of the condenser is higher than that of the liquid receiver. The liquid refrigerant flows back to the liquid receiver by gravity. At this time, there is no need to design a power part to drive the refrigerant, thus achieving the effect of energy saving of the system.

[0025] 3. A compressor bypass valve is designed on the compressor side to bypass the compressor for refrigerant circulation and cooling when the refrigeration system is shut down. The compressor can be used for mechanical cooling in summer and natural cooling in winter to reduce system energy consumption;

[0026] 4. Design a refrigerant pump and a refrigerant pump bypass valve between each liquid receiver and the evaporator to respond to emergencies or actively adjust the flow of different loads at the end to ensure constant temperature control of the end environment;

[0027] 5. The cold storage evaporation module is designed as an integrated device and prefabricated in the factory to simplify the on-site construction and installation process, making it more flexible and convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present invention is described in detail below with reference to the embodiments and drawings, wherein:

[0029] Figure 1 It is a schematic diagram of the structure of some embodiments of the utility model;

[0030] Figure 2 It is a schematic diagram of the refrigerant flow direction of the utility model in the mechanical refrigeration state;

[0031] Figure 3 It is a schematic diagram of the refrigerant flow direction of the utility model under the natural refrigeration state;

[0032] Figure 4 It is a schematic diagram of the refrigerant flow direction of the utility model in the emergency refrigeration state;

[0033] Figure 5 This is a schematic diagram of the structure of the cold storage evaporation module of the utility model;

[0034] Description of the drawings: 1. Compressor; 2. Condenser; 3. Cold storage evaporation module; 31. Evaporator; 311. Evaporation tube; 32. Liquid storage tank; 33. Refrigerant pump; 34. Refrigerant pump bypass valve; 35. Liquid distribution pipe; 36. Gas collecting pipe; 361. Exhaust port of gas collecting pipe; 37. Fan; 4. Liquid return main pipe; 5. Exhaust main pipe; 6. Balance pipe; 7. Compressor bypass valve. DETAILED DESCRIPTION

[0035] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0036] like Figure 1As shown, the refrigeration system proposed by the utility model includes: a compressor 1, a condenser 2 and at least two cold storage evaporation modules 3 arranged in parallel. The compressor 1, the condenser 2 and the cold storage evaporation module 3 are connected to form a refrigerant circulation loop. The refrigerant sent out from the exhaust port of the compressor 1 is sent back to the intake port of the compressor 1 through the condenser 2 and the cold storage evaporation module 3.

[0037] Specifically, the cold storage evaporation module 3 includes an evaporator 31 and a liquid reservoir 32, the exhaust port of the compressor 1 is connected to the inlet of the condenser 2, the outlet of the condenser 2 is provided with a liquid return main pipe 4, the inlet of the liquid reservoir 32 of each cold storage evaporation module 3 is connected to the liquid return main pipe 4, the outlet of the liquid reservoir 32 is connected to the inlet of the evaporator 31, the air intake port of the compressor 1 is provided with an exhaust main pipe 5, the outlet of the evaporator 31 of each cold storage evaporation module 3 is connected to the exhaust main pipe 5, and the liquid reservoirs 32 of all cold storage evaporation modules 3 are connected through a balancing pipe 6 so that the liquid level height of each liquid reservoir 32 is the same.

[0038] The advantage of this design is that since the multiple evaporators in the refrigeration system are connected in parallel with different processes, the larger flow loop often causes insufficient refrigerant flow. The balance pipe 6 is used to connect the liquid reservoir 32 of each evaporator. When the flow through each evaporator 31 is different, the refrigerant in the liquid reservoir with a higher liquid level will flow to the liquid reservoir with a lower liquid level through the balance pipe 6, so that the liquid level height of each liquid reservoir is consistent, ensuring the consistency of the flow of each evaporator, solving the problem of uneven refrigerant flow distribution in the existing parallel evaporators, causing some evaporators to provide insufficient cooling to the end load, thereby achieving stable cooling.

[0039] In some embodiments of the utility model, the installation height of the liquid reservoirs 32 of all cold storage evaporation modules 3 is the same, and the installation height of the condenser 2 is higher than the liquid reservoir 32. The outlet of the condenser 2 is located at the bottom, and the outflowing liquid refrigerant is sent to the liquid reservoir 32 through the liquid return main pipe 4. The advantage of this design is that the liquid refrigerant in the condenser 2 automatically flows back to the liquid reservoir 32 by gravity, and there is no need to design a power part to drive the refrigerant, thereby achieving the effect of energy saving of the system.

[0040] It should be understood that all the cold storage evaporation modules 3 appearing in this article refer to the cold storage evaporation modules connected in parallel in the same refrigeration system. In addition, the condenser 2 appearing in this article preferably adopts an evaporative condenser, which is a heat exchange device that absorbs heat by evaporating water to achieve the purpose of cooling and condensing the refrigerant. It has high cooling efficiency and can operate stably under various working conditions.

[0041] like Figure 1As shown, in some embodiments of the utility model, a compressor bypass branch is connected between the exhaust port and the intake port of the compressor 1, and a compressor bypass valve 7 is installed in the compressor bypass branch. When the compressor is stopped, the compressor bypass valve 7 can be opened to circulate the refrigerant for cooling.

[0042] The advantage of this design is that the refrigeration system is suitable for both mechanical refrigeration and natural refrigeration. When the external ambient temperature is high (for example, in summer), mechanical refrigeration is used, the compressor 1 is turned on, and the compressor bypass valve 7 is closed. After the refrigerant in the evaporator 31 absorbs the terminal heat and vaporizes the phase change, it is sent to the condenser 2 by the compressor 1 for cooling, and then returns to the liquid storage 32 through the liquid return main pipe 4, and then flows to the evaporator 31 for circulation. When the external environment is low (for example, in winter), natural cooling is used, the compressor 1 is turned off, and the compressor bypass valve 7 is opened. After the refrigerant in the evaporator 31 absorbs the terminal heat and vaporizes the phase change, the pressure of the exhaust main pipe 5 increases, and the gaseous refrigerant flows through the compressor bypass valve 7 through the condenser 2 for cooling, and then returns to the liquid storage 32 through the liquid return main pipe 4, and then flows to the evaporator 31 for circulation. The operating state is switched according to the high and low external ambient temperature to ensure the supply of load cooling capacity while reducing system energy consumption.

[0043] On this basis, the utility model also proposes an optimization scheme, the cold storage evaporation module 3 also includes a refrigerant pump 33 and a refrigerant pump bypass valve 34, and the refrigerant in the liquid storage tank 32 is sent to the evaporator 31 through the refrigerant pump 33 or the refrigerant pump bypass valve 34. The advantage of this design is that the refrigerant pump 33 can provide or compensate for the circulation power of the refrigerant, flexibly respond to emergency conditions or actively adjust the flow of different loads at the end to ensure constant temperature control of the environment where the load is located.

[0044] For this preferred solution, the refrigeration system can operate in at least one of the mechanical refrigeration state, the natural refrigeration state, and the emergency refrigeration state. The operation process of each state is described in detail below.

[0045] like Figure 2 As shown, the mechanical refrigeration state is suitable for when the external ambient temperature is high (for example, in summer), the compressor 1 is turned on, the compressor bypass valve 7 is closed, the refrigerant pump 33 is turned off, and the refrigerant pump bypass valve 34 is opened, and the refrigerant in the evaporator 31 absorbs the heat of the terminal load, and the refrigerant gasifies and changes phase and flows into the exhaust main pipe 5, and is sent to the condenser 2 by the compressor 1 for cooling, and then returns to the liquid storage tank 32 through the return liquid main pipe 4, and then returns to the evaporator 31 through the refrigerant pump bypass valve 34 to circulate.

[0046] like Figure 3As shown, the natural refrigeration state is suitable for when the external ambient temperature is low (for example, in winter), the compressor 1 is turned off, the compressor bypass valve 7 is turned on, the refrigerant pump 33 is turned off, and the refrigerant pump bypass valve 34 is turned on. The refrigerant in the evaporator 31 absorbs the heat of the terminal load, and after the refrigerant gasifies and changes phase, the pressure of the exhaust main pipe 5 increases, and the gaseous refrigerant flows through the compressor bypass valve 7, passes through the condenser 2, is cooled, and then returns to the liquid storage tank 32 through the liquid return main pipe 4, and then returns to the evaporator 31 through the refrigerant pump bypass valve 34 to circulate.

[0047] like Figure 4 As shown, the emergency refrigeration state is suitable for when the refrigeration system encounters an emergency or special situation (such as shutdown or shutdown), the compressor 1 is turned off, the compressor bypass valve 7 is opened, and the emergency refrigeration of the evaporator 31 is achieved through the refrigerant stored in the liquid reservoir 32. At this time, the evaporator 31 absorbs the load heat, and the liquid refrigerant evaporates quickly. The liquid refrigerant in the liquid reservoir 32 is sent to the evaporator 31 through the refrigerant pump 33 to prevent the load temperature from rising suddenly and ensure constant temperature control.

[0048] The advantage of this design is that the refrigeration system can flexibly switch operating states to adapt to different usage scenarios. It can not only achieve the technical effects of stable cooling and constant temperature control, but also significantly reduce system energy consumption and improve the user experience.

[0049] It should be understood that in actual application, the number of operating states can be selected according to specific usage requirements, or adaptive adjustments can be made under existing operating states. For example, under natural refrigeration, when the load demand at a certain end changes and the refrigerant flow of the evaporator 31 is insufficient, the refrigerant pump 33 is turned on to increase the refrigerant flow of the evaporator. Other operating states can also be designed based on the connection structure of the refrigeration system, and the present utility model does not impose any special restrictions on this.

[0050] In addition, in order to better match the changes in load demand at the terminal, the refrigerant pump 33 preferably adopts a variable frequency pump with adjustable speed. When the load demand at a certain terminal differs greatly, the refrigerant pump 33 is turned on and the frequency of the refrigerant pump 33 is adjusted, and the refrigerant pump bypass valve 34 is closed to meet different load demands.

[0051] In addition, the shutdown mentioned in this article refers to the temporary cessation of the compressor's operation, and the machine cut-off refers to the refrigeration system having at least two compressors connected in parallel, one compressor is turned off, and the other compressor needs to be turned on for a period of time. During this period of time, the refrigeration system cannot normally supply the cooling load, so it is necessary to use the liquid storage tank and the refrigerant pump for emergency refrigeration. For a refrigeration system with more than two compressors connected in parallel, in the above-mentioned operating state, compressor on means that at least one compressor is turned on, and compressor off means that all compressors are turned off.

[0052] like Figure 5As shown, in some embodiments of the utility model, the cold storage evaporation module 3 also includes a liquid distribution pipe 35, an air collecting pipe 36, and at least one fan 37. The evaporator 31 has a plurality of mutually parallel straight evaporation tubes 311. The top of the evaporation tube 311 is connected to the air collecting pipe 36, and the exhaust port of the air collecting pipe 36 is connected to the exhaust main pipe 5. The bottom of the evaporation tube 311 is connected to the liquid distribution pipe 35. One end of the liquid distribution pipe 35 is connected to the refrigerant pump bypass valve 34 and the other end is connected to the refrigerant pump 33. The liquid storage tank 32 is located below the liquid distribution pipe 35, and the fan 37 drives the airflow through the evaporation tube 311.

[0053] The advantage of this design is that the evaporator 31 has a large heat exchange area and a compact structure. The refrigerant in the evaporator 31 absorbs heat and vaporizes and flows directly to the collecting pipe 36. The refrigerant flow resistance is small, and the fluid direction is more stable and orderly.

[0054] On this basis, the utility model also proposes an optimization scheme, in which the evaporator 31, liquid storage tank 32, refrigerant pump 33, refrigerant pump bypass valve 34, liquid distribution pipe 35, gas collecting pipe 36, and fan 37 of the cold storage evaporation module 3 are assembled to form an integrated device.

[0055] The advantage of this design is that the evaporator 31, the liquid reservoir 32, the refrigerant pump 33 and the refrigerant pump bypass valve 34 are prefabricated in the factory. During on-site installation, it is only necessary to use the balancing pipe 6 to connect the liquid reservoirs 32 of each cold storage evaporation module 3 to ensure that it has the function of energy storage and balancing the process, simplifying the on-site construction and installation process, and making it more flexible and convenient.

[0056] The utility model also proposes an air-conditioning unit adopting the above-mentioned refrigeration system, and the air-conditioning unit includes but is not limited to process air conditioning. Since the refrigeration system is equipped with a liquid reservoir for each evaporator, the liquid reservoirs are connected by a balance pipe to balance the liquid level height of the liquid reservoir, thereby ensuring that the flow of each evaporator is consistent, thereby achieving stable cooling.

[0057] For scenarios with higher requirements for the temperature control range, the air-conditioning unit must ensure continuous cooling. When an emergency or special situation occurs in the unit (such as shutdown or power off), the refrigerant stored in the receiver can provide liquid refrigerant to the evaporator to achieve emergency cooling, prevent the load temperature from rising suddenly, and achieve the technical effect of terminal constant temperature control.

[0058] It should be noted that the terms used above are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the utility model. When the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof. The order of execution of actions, steps, etc. in the devices and methods shown in the specification and the accompanying drawings can be implemented in any order as long as there is no special explicit limitation on the order and the output of the previous processing is not used in the subsequent processing. Similar sequential terms used for the convenience of description do not mean that they must be implemented in such an order.

[0059] Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such techniques, methods, and apparatus should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following figures, and therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A refrigeration system, characterized in that: include: compressor; A condenser, wherein the inlet of the condenser is connected to the exhaust port of the compressor; At least two cold storage evaporation modules are arranged in parallel, the cold storage evaporation modules include an evaporator and a liquid storage tank connected between an inlet of the evaporator and an outlet of the condenser, and the outlet of the evaporator is connected to an air intake port of the compressor; Wherein, the liquid reservoirs of all the cold storage evaporation modules are connected through a balance pipe so that the liquid level height of each liquid reservoir is the same.

2. The refrigeration system according to claim 1, characterized in that: The installation heights of the liquid storage devices of all the cold storage evaporation modules are the same, and the installation height of the condenser is higher than that of the liquid storage device.

3. The refrigeration system according to claim 1 or 2, characterized in that: A compressor bypass branch is connected between the exhaust port and the intake port of the compressor, and a compressor bypass valve is installed on the compressor bypass branch.

4. The refrigeration system according to claim 3, characterized in that: The cold storage evaporation module further comprises a refrigerant pump and a refrigerant pump bypass valve arranged in parallel, and the refrigerant in the accumulator is delivered to the evaporator through the refrigerant pump bypass valve or the refrigerant pump.

5. The refrigeration system according to claim 4, characterized in that: The refrigeration system can operate in at least one of a mechanical refrigeration state, a natural refrigeration state, and an emergency refrigeration state; When operating in a mechanical refrigeration state, the compressor is turned on, the compressor bypass valve is closed, the refrigerant pump is turned off, and the refrigerant pump bypass valve is opened; and / or when operating in a natural cooling state, the compressor is turned off, the compressor bypass valve is opened, the refrigerant pump is turned off, and the refrigerant pump bypass valve is opened; And / or when operating in an emergency refrigeration state, the compressor is turned off, the compressor bypass valve is opened, the refrigerant pump is turned on, and the refrigerant pump bypass valve is closed.

6. The refrigeration system according to claim 4, characterized in that: The cold storage evaporation module further comprises an air collecting pipe, a liquid distributing pipe, and at least one fan, and the evaporator comprises a plurality of evaporation pipes, the top of each evaporation pipe is connected to the air collecting pipe, and the bottom of each evaporation pipe is connected to the liquid distributing pipe; The exhaust port of the air collecting pipe is connected to the air intake port of the compressor, one end of the liquid distribution pipe is connected to the refrigerant pump bypass valve and the other end is connected to the refrigerant pump, and the fan drives the air flow to pass through the evaporating tube.

7. The refrigeration system according to claim 6, characterized in that: The evaporator, liquid storage tank, refrigerant pump, refrigerant pump bypass valve, gas collecting pipe, liquid distribution pipe and fan of the cold storage evaporation module are assembled into an integrated device.

8. The refrigeration system according to claim 4, characterized in that: The refrigerant pump is a variable frequency pump with adjustable speed.

9. The refrigeration system according to claim 1, characterized in that: The condenser is an evaporative condenser.

10. An air conditioning unit, characterized in that: The air conditioning unit comprises the refrigeration system according to any one of claims 1 to 9.

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