Full-injection ejector refrigerating circuit

Abstract

The utility model discloses a full-injection ejector refrigerating circuit which comprises a plurality of compressors, a heat removal heat exchanger / gas cooler, an ejector and a receiver. The inlet end of the compressor unit is connected with a gas outlet of the receiver, the outlet end of the compressor unit is connected with a three-way valve, and one end of the three-way valve is connected with the inlet end of the heat removal heat exchanger / gas cooler through a bypass pipe. A heat recoverer is connected in series between the other end of the three-way valve and the inlet end of the heat removal heat exchanger / gas cooler; an outlet end of the heat rejection heat exchanger / gas cooler is connected with a main high-pressure input port of the ejector, and an inlet of the receiver is connected with an output port of the ejector; a secondary low-pressure input port of the ejector is connected with a liquid outlet end of the receiver through a refrigerating pipe group; according to the utility model, the energy recovery efficiency of the ejector is improved, so that the system can still operate efficiently under the conditions of low pressure difference, low load and multiple working conditions.

Description

Technical Field

[0001] The utility model belongs to the technical field of refrigeration systems, and specifically relates to a full-ejector refrigeration circuit. Background Art

[0002] In a refrigeration circuit, an ejector is usually used as an expansion device. By utilizing the expansion energy of the refrigerant from high pressure to medium pressure, the low-pressure refrigerant is compressed to medium pressure to achieve energy recovery. Traditional ejector systems can maintain a high operating efficiency under high pressure difference conditions, but when the pressure difference is small, the system efficiency drops significantly, which limits its performance under specific working conditions, especially its application under load fluctuations or low pressure drop conditions.

[0003] Existing ejector refrigeration systems, especially those using carbon dioxide (CO2) as the refrigerant, have been widely used in industrial refrigeration, commercial air conditioning, and cold chain logistics fields. However, most current systems adopt a partial ejection design (such as CN103282730A), that is, part of the refrigerant in the low-temperature circuit directly enters the compressor, failing to fully utilize the expansion function of the ejector, resulting in energy efficiency loss, especially a significant drop in efficiency under low pressure difference working conditions. In addition, the prior art fails to combine a liquid pump, an ejector, and a bypass branch, which limits the adaptability of the system under different climate conditions and cannot meet the high-efficiency operation requirements under multiple working conditions.

[0004] Many companies and research teams have invested a large amount of R & D resources in the refrigeration field, especially in the optimization of ejector refrigeration systems. Although the existing systems perform well under high load conditions, the problem of efficiency decline under low pressure difference and multi-condition operation has not been completely solved. In addition, under extreme climate conditions such as cold or hot, there are also certain limitations in the all-region adaptability and dynamic response performance of the existing technology.

[0005] In summary, although the prior art has made significant progress in ejector refrigeration systems, there is still much room for improvement, especially in aspects such as energy efficiency improvement under low pressure difference working conditions, multi-mode operation design, adaptability to all-region environments, and optimization of bypass circuit structures. There is an urgent need for new technical solutions to overcome the bottlenecks of the prior art. Summary of the Utility Model

[0006] To solve the defects existing in the prior art, the utility model provides a full-ejector refrigeration circuit.

[0007] To solve the above technical problems, the utility model provides the following technical solutions:

[0008] The present utility model relates to a refrigeration circuit of a full-ejector ejector, which includes a plurality of compressors, a heat rejection heat exchanger / gas cooler, an ejector and a receiver. The plurality of compressors are connected in parallel to form a compressor unit. The inlet end of the compressor unit is connected to the gas outlet of the receiver. The outlet end of the compressor unit is connected to a three-way valve, and a bypass pipe is connected between one end of the three-way valve and the inlet end of the heat rejection heat exchanger / gas cooler. A heat recovery device is connected in series between the other end of the three-way valve and the inlet end of the heat rejection heat exchanger / gas cooler;

[0009] The outlet end of the heat rejection heat exchanger / gas cooler is connected to the main high-pressure input port of the ejector, and the inlet of the receiver is connected to the output port of the ejector;

[0010] The secondary low-pressure input port of the ejector is connected to the liquid outlet end of the receiver through a refrigeration pipe group.

[0011] As a preferred technical solution of the present utility model, the refrigeration pipe group includes a first refrigeration pipeline and a second refrigeration pipeline connected in parallel between the secondary low-pressure input port of the ejector and the liquid outlet of the receiver;

[0012] The first refrigeration pipeline includes a plurality of low-temperature compressors, a low-temperature evaporator and a low-temperature expansion device; the plurality of low-temperature compressors are connected in parallel to form a low-temperature compressor unit. The secondary low-pressure input port of the ejector is connected to the outlet end of the low-temperature compressor unit, and the low-temperature evaporator and the low-temperature expansion device are connected in series between the liquid outlet end of the receiver and the inlet end of the low-temperature compressor unit.

[0013] As a preferred technical solution of the present utility model, the second refrigeration pipeline includes a refrigeration evaporator, a refrigeration expansion device, a bypass valve and a liquid pump;

[0014] The output end of the refrigeration evaporator is connected to the secondary low-pressure input port of the ejector, and the input end of the refrigeration evaporator is connected to the output end of the refrigeration expansion device. The bypass valve and the liquid pump are connected in parallel between the output end of the refrigeration expansion device and the liquid outlet end of the receiver.

[0015] As a preferred technical solution of the present utility model, it further includes a controller, and the liquid pump, the compressor and the ejector are all connected to the controller.

[0016] As a preferred technical solution of the present utility model, a first pressure gauge is provided at the output end of the heat rejection heat exchanger / gas cooler.

[0017] As a preferred technical solution of the present utility model, a second pressure gauge is provided at the output port of the ejector.

[0018] The beneficial effects of the present utility model are:

[0019] 1. In the refrigeration circuit of this full-ejector ejector, the protective housing adopts a full-ejector circuit design to ensure that the entire refrigerant flow passes through the ejector, avoiding the energy efficiency loss caused by bypass shunting in the prior art, especially performing well in the application of low-temperature liquid circuits. And a three-way valve is connected to the outlet end of the compressor unit, and a bypass pipe is connected between one end of the three-way valve and the inlet end of the heat rejection heat exchanger / gas cooler, and a heat recovery device is connected in series between the other end of the three-way valve and the inlet end of the heat rejection heat exchanger / gas cooler, so as to further cool down and increase the temperature of the subsequent medium-high pressure refrigerant, improving the energy recovery efficiency of the ejector. All the refrigerants in the low-temperature circuit enter the ejector for expansion and mixing, without bypass shunting. This full-ejector design ensures that every part of the refrigerant is fully utilized, significantly improving the energy recovery efficiency of the ejector and enabling the system to still operate efficiently under conditions of low pressure difference, low load, and multiple working conditions. Description of the Drawings

[0020] Figure 1 It is a schematic structural diagram of a refrigeration circuit of a full-ejector ejector of the present invention.

[0021] In the figure: 1. Compressor; 2. Heat rejection heat exchanger / gas cooler; 3. Ejector; 4. Receiver; 5. Three-way valve; 6. Bypass pipe; 7. Heat recovery device; 8. First refrigeration pipeline; 801. Low-temperature compressor; 802. Low-temperature evaporator; 803. Low-temperature expansion device; 9. Second refrigeration pipeline; 901. Refrigeration evaporator; 902. Refrigeration expansion device; 903. Bypass valve; 904. Liquid pump; 10. First pressure gauge; 11. Second pressure gauge; 12. Controller.

[0022] It should be noted that these drawings and text descriptions are not intended to limit the scope of the concept of the present invention in any way, but to illustrate the concept of the present invention to those skilled in the art by referring to specific embodiments. Detailed Embodiments

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention, but are not used to limit the scope of the present invention.

[0024] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

[0025] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0026] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, the meaning of "a plurality of" is two or more unless otherwise clearly and specifically defined.

[0027] As Figure 1 shown, a full ejector refrigeration cycle of the present utility model includes a plurality of compressors 1, a heat rejection heat exchanger / gas cooler 2, an ejector 3, and a receiver 4. The plurality of compressors 1 are connected in parallel to form a compressor unit. The inlet end of the compressor unit is connected to the gas outlet of the receiver 4. The outlet end of the compressor unit is connected to a three-way valve 5. And a bypass pipe 6 is connected between one end of the three-way valve 5 and the inlet end of the heat rejection heat exchanger / gas cooler 2. A heat recovery device 7 is connected in series between the other end of the three-way valve 5 and the inlet end of the heat rejection heat exchanger / gas cooler 2; thus, further cooling is performed to increase the temperature of the subsequent medium-high pressure refrigerant, and the efficiency of high-pressure refrigerant expansion and low-pressure refrigerant suction is increased.

[0028] The outlet end of the heat rejection heat exchanger / gas cooler 2 is connected to the main high-pressure input port of the ejector 3. The inlet of the receiver 4 is connected to the output port of the ejector 3;

[0029] The secondary low-pressure input port of the ejector 3 is connected to the liquid outlet end of the receiver 4 through a refrigeration pipe group. The full-ejector loop design is adopted to ensure that the entire refrigerant flow passes through the ejector 3, avoiding the energy efficiency loss caused by bypass shunting in the prior art, especially performing well in the application of low-temperature liquid circuits; and a three-way valve 5 is connected to the outlet end of the compressor 1 group, and one end of the three-way valve 5 is connected to the inlet end of the heat rejection heat exchanger / gas cooler 2 through a bypass pipe 6, and a heat recovery device 7 is connected in series between the other end of the three-way valve 5 and the inlet end of the heat rejection heat exchanger / gas cooler 2, so as to further cool down and increase the temperature of the subsequent medium-high pressure refrigerant, improving the energy recovery efficiency of the ejector. All the refrigerants in the low-temperature circuit enter the ejector 3 for expansion and mixing, without bypass shunting. This full-ejector design ensures that every part of the refrigerant is fully utilized, significantly improving the energy recovery efficiency of the ejector 3, enabling the system to still operate efficiently under low pressure difference, low load and multi-condition conditions.

[0030] Wherein, the refrigeration pipe group includes a first refrigeration pipeline 8 and a second refrigeration pipeline 9 connected in parallel between the secondary low-pressure input port of the ejector 3 and the liquid outlet of the receiver 4;

[0031] The first refrigeration pipeline 8 includes a plurality of low-temperature compressors 801, a low-temperature evaporator 802 and a low-temperature expansion device 803; a plurality of the low-temperature compressors 801 are connected in parallel to form a low-temperature compressor unit, the secondary low-pressure input port of the ejector 3 is connected to the outlet end of the low-temperature compressor unit, and the low-temperature evaporator and the low-temperature expansion device are connected in series between the liquid outlet end of the receiver 4 and the inlet end of the low-temperature compressor unit. Refrigeration can be carried out through the first refrigeration pipeline 8 in the case of a pressure group.

[0032] Wherein, the second refrigeration pipeline 9 includes a refrigeration evaporator 901, a refrigeration expansion device 902, a bypass valve 903 and a liquid pump 904;

[0033] The output end of the refrigeration evaporator 901 is connected to the secondary low-pressure input port of the ejector 3, and the input end of the refrigeration evaporator 901 is connected to the output end of the refrigeration expansion device 902, and the bypass valve 903 and the liquid pump 904 are connected in parallel between the output end of the refrigeration expansion device 902 and the liquid outlet end of the receiver (4). The liquid pump 904 increases the refrigerant pressure when the pressure is insufficient, thus overcoming the defect of low efficiency under low pressure difference conditions.

[0034] Wherein, it further includes a controller 12, and the liquid pump 904, the compressor 1 and the ejector 3 are all connected to the controller 12. Wherein, a first pressure gauge 10 is provided at the output end of the heat rejection heat exchanger / gas cooler 2. A second pressure gauge 11 is provided at the output port of the ejector 3.

[0035] Working principle: The compressor 1 compresses the refrigerant and sends it into the heat rejection heat exchanger 2. After cooling, it flows into the ejector 3. Inside the ejector 3, the high-pressure refrigerant expands and sucks in the low-pressure refrigerant from the refrigeration evaporator. After mixing, it flows into the receiver 4 to separate the refrigerant into gas phase and liquid phase. The gas phase part returns to the compressor 1, and the liquid phase part enters the first refrigeration pipeline or the second refrigeration pipeline for refrigeration. The liquid pump 904 increases the refrigerant pressure when the pressure is insufficient, enabling it to enter the evaporator through the expansion device to complete the refrigeration cycle, so that the system can still operate efficiently under low pressure difference, low load and multi-condition conditions.

[0036] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0037] The above is only a preferred embodiment of the present invention, and does not impose any form of limitation on the present invention. Although the present invention has been disclosed above with a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art of this patent, without departing from the scope of the technical solution of the present invention, can make some modifications or decorations with equivalent changes using the technical content prompted above as equivalent embodiments. The implementation schemes in the above embodiments can also be further combined or replaced. However, as long as it does not depart from the content of the technical solution of the present invention, any simple modification, equivalent change and decoration made to the above embodiments according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A full ejector refrigeration circuit, comprising a plurality of compressors (1), a heat rejection heat exchanger / gas cooler (2), an ejector (3) and a receiver (4), characterized in that: A plurality of the compressors (1) are connected in parallel to form a compressor unit, the inlet end of the compressor unit is connected to the gas outlet of the receiver (4), the outlet end of the compressor unit is connected to a three-way valve (5), one end of the three-way valve (5) is connected to the inlet end of the heat exhaust heat exchanger / gas cooler (2) via a bypass pipe (6), and a heat recovery device (7) is connected in series between the other end of the three-way valve (5) and the inlet end of the heat exhaust heat exchanger / gas cooler (2); The outlet end of the heat rejection heat exchanger / gas cooler (2) is connected to the main high-pressure input port of the ejector (3), and the inlet of the receiver (4) is connected to the output port of the ejector (3); The secondary low-pressure input port of the ejector (3) is connected to the liquid outlet of the receiver (4) via a refrigeration pipe group.

2. A full ejector refrigeration circuit according to claim 1, characterized in that: The refrigeration pipe group comprises a first refrigeration pipe (8) and a second refrigeration pipe (9) connected in parallel between the secondary low-pressure input port of the ejector (3) and the liquid outlet of the receiver (4); The first refrigeration pipeline (8) includes a plurality of low-temperature compressors (801), a low-temperature evaporator (802) and a low-temperature expansion device (803); the plurality of low-temperature compressors (801) are connected in parallel to form a low-temperature compressor group, the secondary low-pressure input port of the ejector (3) is connected to the outlet end of the low-temperature compressor group, and the low-temperature evaporator (802) and the low-temperature expansion device (803) are connected in series between the liquid outlet end of the receiver (4) and the inlet end of the low-temperature compressor group.

3. A full ejector refrigeration circuit according to claim 2, characterized in that: The second refrigeration pipeline (9) comprises a refrigeration evaporator (901), a refrigeration expansion device (902), a bypass valve (903) and a liquid pump (904); The output end of the refrigeration evaporator (901) is connected to the secondary low-pressure input port of the ejector (3), and the input end of the refrigeration evaporator (901) is connected to the output end of the refrigeration expansion device (902), and the bypass valve (903) and the liquid pump (904) are connected in parallel between the output end of the refrigeration expansion device (902) and the liquid outlet end of the receiver (4).

4. A full ejector refrigeration circuit according to claim 3, characterized in that: It also includes a controller (12), and the liquid pump (904), the compressor (1) and the ejector (3) are all connected to the controller (12).

5. The full ejector refrigeration circuit according to claim 1, characterized in that: The output end of the heat rejection heat exchanger / gas cooler (2) is provided with a first pressure gauge (10).

6. A full ejector refrigeration circuit according to claim 1, characterized in that: A second pressure gauge (11) is provided on the output port of the injector (3).

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