Reverse Brayton air refrigeration system

Abstract

The utility model relates to a reverse Brayton air refrigeration system which comprises an air compressor, a cooler, a dehumidification device, a heat regenerator, an expansion machine, a flow regulating valve and a cold heat exchanger. An outlet of the air compressor is communicated with an inlet of the cooler, an outlet of the cooler is communicated with an inlet of the dehumidification device, an outlet of the dehumidification device is communicated with a hot side inlet of the heat regenerator, and a hot side outlet of the heat regenerator is communicated with an inlet of the expansion machine. An outlet of the expansion machine is communicated with the flow regulating valve and the cold heat exchanger in parallel, an outlet of the flow regulating valve and an outlet of the cold heat exchanger are converged into a flow path to be communicated with a cold side inlet of the heat regenerator, and a cold side outlet of the heat regenerator is communicated with an inlet of the air compressor. The defects that an open air refrigeration system is large in dehumidification capacity and noise are overcome, and the defects that a closed air refrigeration system is small in refrigerating capacity and complex in design and manufacturing can be overcome.

Description

Technical Field

[0001] The utility model relates to a reverse Brayton air refrigeration system. Background Art

[0002] With the advancement of the dual-carbon process, the air refrigeration system based on the reverse Brayton cycle has developed rapidly because its circulating working fluid is environmentally friendly and cheap air.

[0003] At present, the reverse Brayton air refrigeration system is mainly divided into an open refrigeration system and a closed refrigeration system, and both systems have their own shortcomings. The open refrigeration system needs to dehumidify the air to reduce the dew point temperature of the air to prevent condensation and ice formation in the air when the air temperature drops, which causes the system to fail to operate normally. In addition, when the air is discharged into the atmosphere during open operation, a large noise is generated. For closed refrigeration systems, a compression-expansion integrated machine design is generally adopted. This system generally has a small cooling capacity, and the compressor and expander need to be matched in design, and the design and manufacturing costs are high. Therefore, a reverse Brayton air refrigeration system is proposed to address the above problems. Utility Model Content

[0004] The utility model aims to overcome the existing defects and provide a reverse Brayton air refrigeration system, reduce the open air refrigeration system's shortcomings of large dehumidification capacity and high noise, and improve the closed air refrigeration system's shortcomings of small refrigeration capacity and complex design and manufacturing.

[0005] The technical solution to achieve the above object is: a reverse Brayton air refrigeration system, including an air compressor, a cooler, a dehumidifier, a regenerator, an expander, a flow regulating valve and a cold heat exchanger;

[0006] The outlet of the air compressor is connected to the inlet of the cooler, the outlet of the cooler is connected to the inlet of the dehumidifier, the outlet of the dehumidifier is connected to the hot side inlet of the regenerator, the hot side outlet of the regenerator is connected to the inlet of the expander, the outlet of the expander is connected to the flow regulating valve and the cold heat exchanger in parallel, the outlets of the flow regulating valve and the cold heat exchanger merge into one flow path and are connected to the cold side inlet of the regenerator, and the cold side outlet of the regenerator is connected to the inlet of the air compressor.

[0007] Preferably, it further comprises an air intake valve, wherein the air intake valve is connected between the cold side outlet of the regenerator and the inlet of the air compressor, and the other end of the air intake valve is connected to an air filter.

[0008] Preferably, a first pressure sensor is connected between the outlet of the cooler and the inlet of the dehumidification device.

[0009] Preferably, a second pressure sensor is connected between the cold side outlet of the regenerator and the inlet of the air compressor.

[0010] Preferably, the cooler is air-cooled or water-cooled.

[0011] Preferably, the dehumidification device includes a cold dryer and an adsorption dehumidifier, and the cold dryer and the adsorption dehumidifier are combined for dehumidification.

[0012] The beneficial effects of the utility model are as follows: the inverse Brayton air refrigeration system can reduce the disadvantages of the open air refrigeration system, which has a large dehumidification capacity and a large noise, and can also improve the disadvantages of the closed air refrigeration system, which has a small refrigeration capacity and a complex design and manufacturing. By combining the advantages of the open air refrigeration system and the closed air refrigeration system, the system can be started in an open manner and operated in a closed manner, and the air dehumidification capacity can be greatly reduced while the refrigeration capacity is improved, and the noise during the operation of the system is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the reverse Brayton air refrigeration system of the utility model.

[0014] In the figure: 1. air compressor; 2. cooler; 3. dehumidification device; 4. regenerator; 5. expander; 6. flow control valve; 7. cold heat exchanger; 8. air filter; 9. intake valve; 10-1. first pressure sensor; 10-2. second pressure sensor. DETAILED DESCRIPTION

[0015] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0016] The utility model will be further described below in conjunction with the accompanying drawings.

[0017] like Figure 1As shown, a reverse Brayton air refrigeration system includes an air compressor 1, a cooler 2, a dehumidifier 3, a regenerator 4, an expander 5, a flow regulating valve 6 and a cold heat exchanger 7; the outlet of the air compressor 1 is connected to the inlet of the cooler 2, the outlet of the cooler 2 is connected to the inlet of the dehumidifier 3, the outlet of the dehumidifier 3 is connected to the hot side inlet of the regenerator 4, the hot side outlet of the regenerator 4 is connected to the inlet of the expander 5, the outlet of the expander 5 is connected to the flow regulating valve 6 and the cold heat exchanger 7 in parallel, the outlets of the flow regulating valve 6 and the cold heat exchanger 7 merge into one flow path and are connected to the cold side inlet of the regenerator 4, and the cold side outlet of the regenerator 4 is connected to the inlet of the air compressor 1.

[0018] Specifically, it also includes an air intake valve 9 . The air intake valve 9 is connected between the cold side outlet of the regenerator 4 and the inlet of the air compressor 1 , and the other end of the air intake valve 9 is connected to an air filter 8 .

[0019] Specifically, a first pressure sensor 10-1 is connected between the outlet of the cooler 2 and the inlet of the dehumidifier 3. A second pressure sensor 10-2 is connected between the cold side outlet of the regenerator 4 and the inlet of the air compressor 1. Both the first pressure sensor 10-1 and the second pressure sensor 10-2 are existing devices, and the model is AP-C30 series.

[0020] Specifically, the air compressor 1 provides power for air circulation, and standard models with different flow rates and exhaust pressures can be selected according to the demand for cooling capacity. The outlet of the air compressor 1 is connected to the inlet of the cooler 2. The air is compressed by the air compressor 1 and discharged into the cooler 2 for cooling. The air enters the cooler 2 for cooling. The cooler 2 can be air-cooled or water-cooled. The high-temperature and high-pressure air is cooled in the cooler 2 into low-temperature and high-pressure air with a lower temperature.

[0021] Specifically, the outlet of the cooler 2 is connected to the inlet of the dehumidifier 3. The dehumidifier 3 can be a combination of a cold dryer and an adsorption dehumidifier, or other dehumidification equipment that can reduce the dew point temperature of the air to below -40°C. The low-temperature and high-pressure air reduces the dew point temperature to below -40°C in the dehumidifier 3. The outlet of the dehumidifier 3 is connected to the hot side inlet of the regenerator 4, and the temperature is further reduced in the regenerator 4 to obtain a lower air outlet temperature after expansion.

[0022] Specifically, the hot side outlet of the regenerator 4 is connected to the inlet of the expander 5, and the low-temperature and high-pressure air is expanded by the expander 5 to obtain low-temperature and low-pressure air with a lower temperature at the outlet. The outlet of the expander 5 is divided into two paths, one of which is connected to the inlet of the flow control valve 6, and the other is connected to the inlet of the cold heat exchanger 7. The flow control valve 6 is used to control the air flow entering the cold heat exchanger 7. The cold heat exchanger 7 is used to exchange heat between low-temperature air and other refrigerant media, and output the coldness of the low-temperature air.

[0023] Specifically, the outlet of the flow control valve 6 and the outlet of the cold heat exchanger 7 merge into one flow path and are connected to the cold side inlet of the regenerator 4. The cold and hot air are heat exchanged in the regenerator 4.

[0024] Specifically, the cold side outlet of the regenerator 4 is connected to the inlet of the air compressor 1, and the low-pressure air close to normal temperature enters the air compressor 1 and is recompressed by the air compressor, thereby entering the next cycle.

[0025] Specifically, the outlet of the air intake valve 9 is connected to the cold side outlet of the regenerator 4 and the inlet pipeline of the air compressor 1, and the inlet of the air intake valve 9 is connected to the outlet of the air filter 8. The air intake valve 9 is used for system air intake, and the air filter 8 is used for filtering the incoming air.

[0026] Specifically, the pressure sensor 10-1 is connected to the pipeline between the outlet of the cooler 2 and the dehumidifier 3 to monitor the exhaust pressure of the compressor. The pressure sensor 10-2 is connected to the cold side outlet of the regenerator 4 and the inlet pipeline of the air compressor 1 to monitor the intake pressure of the air compressor 1.

[0027] Specifically, when the air refrigeration system is running, the air compressor 1 is started, the air inlet valve 9 is opened, and the flow regulating valve 6 is closed. At this time, the air in the environment passes through the air filter 8 and the air inlet valve 9 into the air compressor 1, and is compressed by the air compressor 1, cooled by the cooler 2, dehumidified by the dehumidifier 3, and further cooled by the regenerator 4 before entering the expander 5 for expansion. The low-temperature and low-pressure air at the outlet of the expander 5 enters the cold heat exchanger 7 for heat exchange, and then returns to the inlet of the air compressor 1 through the regenerator 4 to be compressed again, and then the next identical cycle is carried out. The first pressure sensor 10-1 monitors the exhaust pressure of the air compressor 1 all the time. When the first pressure sensor 10-1 detects that the exhaust pressure reaches the set value, the air inlet valve 9 is closed. At this time, the refrigeration system is isolated from the outside world, and the air in the system circulates internally. At this time, the dehumidification load of the dehumidifier 3 is greatly reduced. The second pressure sensor 10-2 monitors the suction pressure of the air compressor 1 all the time. When the second pressure sensor 10-2 detects that the intake pressure of the air compressor 1 is lower than the set value, the intake valve 9 is opened, and the air in the external environment is added to the circulation system to restore the system operating pressure to a normal value. When the load of the cold heat exchanger 7 is reduced, the opening of the flow regulating valve 6 is adjusted to reduce the low-temperature air flow entering the cold heat exchanger 7, thereby matching the heat load of the cold heat exchanger 7.

[0028] This reverse Brayton air refrigeration system can not only reduce the disadvantages of large dehumidification capacity and high noise of the open air refrigeration system, but also improve the disadvantages of small cooling capacity and complex design and manufacturing of the closed air refrigeration system. Combining the advantages of the open air refrigeration system and the closed air refrigeration system, the system can be started in open mode and operated in closed mode. While increasing the cooling capacity, it greatly reduces the air dehumidification capacity and reduces the noise during system operation.

[0029] The above embodiments are only used to illustrate the technical solution of the utility model, rather than to limit it. Although the utility model is described in detail with reference to the above embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the above embodiments, or replace some or all of the technical features therein with equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the utility model.

Claims

1. A reverse Brayton air refrigeration system, characterized in that: It comprises an air compressor (1), a cooler (2), a dehumidifier (3), a regenerator (4), an expander (5), a flow regulating valve (6) and a cold heat exchanger (7); The outlet of the air compressor (1) is connected to the inlet of the cooler (2), the outlet of the cooler (2) is connected to the inlet of the dehumidifier (3), the outlet of the dehumidifier (3) is connected to the hot side inlet of the regenerator (4), the hot side outlet of the regenerator (4) is connected to the inlet of the expander (5), the outlet of the expander (5) is connected in parallel to the flow regulating valve (6) and the cold heat exchanger (7), the outlets of the flow regulating valve (6) and the cold heat exchanger (7) merge into one flow path and are connected to the cold side inlet of the regenerator (4), and the cold side outlet of the regenerator (4) is connected to the inlet of the air compressor (1).

2. The reverse Brayton air refrigeration system according to claim 1, characterized in that: It also includes an air intake valve (9), which is connected between the cold side outlet of the regenerator (4) and the inlet of the air compressor (1), and the other end of the air intake valve (9) is connected to an air filter (8).

3. The reverse Brayton air refrigeration system according to claim 1, characterized in that: A first pressure sensor (10-1) is connected between the outlet of the cooler (2) and the inlet of the dehumidification device (3).

4. The reverse Brayton air refrigeration system according to claim 1, characterized in that: A second pressure sensor (10-2) is connected between the cold side outlet of the regenerator (4) and the inlet of the air compressor (1).

5. The reverse Brayton air refrigeration system according to claim 1, characterized in that: The cooler (2) is air-cooled or water-cooled.

6. The reverse Brayton air refrigeration system according to claim 1, characterized in that: The dehumidification device (3) comprises a cold dryer and an adsorption dehumidifier, and the cold dryer and the adsorption dehumidifier are combined for dehumidification.

Images