CN112050493A - Refrigeration system for injection supercooling and control method thereof - Google Patents

Abstract

The invention provides a refrigeration system and a control method thereof with ejection of subcooling. The air outlet of the compressor of the refrigeration system is communicated with the first port of the four-way reversing valve, and the second port of the four-way reversing valve is connected with the first heat exchange One end of the first heat exchanger is communicated with the first throttling element, the other end of the first throttling element is communicated with the first end of the second heat exchanger, and the other end of the second heat exchanger is communicated with the four-way reversing valve The third port of the four-way reversing valve is communicated with the air inlet of the compressor; it also includes an ejector and a subcooler, and the inlet end of the ejector is communicated with the air outlet of the compressor. The outlet end of the subcooler is communicated with the air inlet of the compressor, the inlet end of the subcooler is communicated with the first heat exchanger, and the inlet end of the subcooler is also communicated with the second heat exchanger; the first outlet end of the subcooler is communicated with the second heat exchanger. It communicates with the ejector subcooling interface of the ejector, and the second outlet end of the subcooler communicates with the first throttling element; the above solution can ensure that the energy efficiency ratio COP and the performance of the refrigeration system are improved.

Description

Refrigeration system with ejection subcooling and control method thereof

technical field

The invention belongs to the technical field of refrigeration, and particularly relates to a refrigeration system with ejection supercooling and a control method thereof.

Background technique

The existing compression refrigeration cycle mainly consists of a compressor, a condenser, an evaporator and a throttling element to form a refrigeration cycle. For the refrigeration cycle, the energy efficiency ratio is an important indicator for judging the energy saving of the refrigeration cycle. In the existing compression refrigeration cycle, the operation of the refrigeration system is unstable, and the system energy efficiency ratio COP is low. Based on the technical problems existing in the above-mentioned compression refrigeration cycle, there is no relevant solution yet; therefore, it is urgent to seek an effective solution to solve the above-mentioned problems.

SUMMARY OF THE INVENTION

The purpose of the present invention is to solve the problem of unstable operation of the refrigeration system in the existing compression refrigeration cycle, aiming at the deficiencies existing in the above-mentioned technologies, and to propose a refrigeration system with ejection subcooling and a control method thereof.

The invention provides a refrigeration system with ejection subcooling, comprising a compressor, a first heat exchanger, a first throttle element, a second heat exchanger and a four-way reversing valve; the air outlet of the compressor is exchanged with the four-way valve. The first port of the directional valve communicates with the first port of the four-way reversing valve, the second port of the four-way reversing valve communicates with one end of the first heat exchanger, and the other end of the first heat exchanger communicates with the first throttling element through the first branch. The other end of the throttling element communicates with the first end of the second heat exchanger through the second branch, and the other end of the second heat exchanger communicates with the third port of the four-way reversing valve. The four ports are communicated with the air inlet of the compressor; the refrigeration system also includes an ejector and a subcooler, the inlet end of the ejector is communicated with the air outlet of the compressor through the third branch, and the outlet end of the ejector The four branches communicate with the air inlet of the compressor, the inlet end of the subcooler communicates with the first heat exchanger through the fifth branch, and the inlet end of the subcooler also communicates with the second heat exchanger through the sixth branch The first outlet end of the subcooler is also communicated with the ejector subcooling interface of the ejector through the seventh branch, and the second outlet end of the subcooler is also communicated with the first throttling element through the eighth branch.

Further, a heat exchange tube is arranged between the inlet end and the second outlet end of the subcooler; the heat exchange tube exchanges heat with the high-temperature refrigerant in the subcooler; the second outlet end of the subcooler passes through the tenth branch. The road communicates with the subcooler; the tenth branch is provided with a second throttling element; the second branch communicates with the first heat exchanger through the ninth branch; the second branch is located at the connection port of the ninth branch and the first heat exchanger. A sixth solenoid valve is arranged between the two heat exchangers.

Further, the third branch is provided with a seventh solenoid valve, and the fourth branch is provided with a one-way valve; the refrigeration system realizes the use of the ejector and the non-use of the ejector according to the opening and closing of the seventh solenoid valve Switching between the two working conditions.

Further, the refrigeration system further includes an eleventh branch, one end of the eleventh branch is connected with the fifth branch and the sixth branch respectively, and the other end of the eleventh branch is connected with the inlet end of the subcooler; A fourth solenoid valve is arranged on one branch, a first electromagnetic valve is arranged on the fifth branch, and a fifth electromagnetic valve is arranged on the sixth branch.

Further, one end of the sixth branch is connected to the second branch, and the interface between the sixth branch and the second branch is located between the sixth solenoid valve and the second heat exchanger.

Further, when the refrigeration system is in the condition of using the ejector refrigeration cycle, the first solenoid valve, the seventh solenoid valve, the fourth solenoid valve and the sixth solenoid valve are in an open state, the second solenoid valve, the third solenoid valve and the The fifth solenoid valve is in the closed state; the high-temperature and high-pressure gaseous refrigerant from the compressor outlet is divided into two paths, one path enters the first heat exchanger through the first port of the four-way reversing valve, and the other path enters the first heat exchanger through the seventh solenoid valve Ejector; the liquid refrigerant from the first heat exchanger enters the subcooler for cooling and is divided into two paths, one path enters the second heat exchanger through the first throttling element, and the other path is throttled to a low temperature through the second throttling element The low-pressure gas-liquid two-phase enters the subcooler, and exchanges heat with the high-temperature refrigerant in the subcooler. After mixing, it becomes a gaseous refrigerant, and then passes through the one-way valve to the compressor.

Further, when the refrigeration system is in the heating cycle using the ejector, the seventh solenoid valve, the fifth solenoid valve, the fourth solenoid valve and the second solenoid valve are in an open state, and the first solenoid valve and the third solenoid valve are in an open state. , The sixth solenoid valve is in the closed state; the high temperature and high pressure gaseous refrigerant from the compressor outlet is divided into two paths, one path enters the second heat exchanger through the first port of the four-way reversing valve, and the other path passes through the seventh solenoid valve Enter the ejector; the liquid refrigerant from the second heat exchanger enters the subcooler for cooling and is divided into two paths, one path is throttled by the first throttling element and then enters the first heat exchanger through the second solenoid valve, and the other path After the second throttling element is throttled into low temperature and low pressure gas-liquid two-phase, it enters the subcooler, and exchanges heat with the high-temperature refrigerant in the subcooler, and then enters the ejector through the subcooling interface of the ejector, and communicates with the ejector. The high temperature and high pressure gaseous refrigerant sucked in the injector is mixed into a gaseous refrigerant, and then passes into the compressor through the one-way valve.

Further, when the refrigeration system is in a cooling condition, the first heat exchanger is a condenser, and the second heat exchanger is an evaporator; when the refrigeration system is in a heating condition, the first heat exchanger is an evaporator, and the second heat exchanger is an evaporator. The second heat exchanger is a condenser; and/or, the first throttling element is an electronic expansion valve, a thermal expansion valve or a capillary tube.

Correspondingly, the present invention also provides a control method for a refrigeration system with ejection of subcooling, which is applied to the refrigeration system described above; the refrigeration system includes a working condition with an ejector and a working condition without an ejector, and In the refrigeration system, the working condition of using the ejector and the working condition of not using the ejector can be switched; the working condition of using the ejector includes:

When the refrigeration system is in the condition of using the ejector refrigeration cycle, the high temperature and high pressure gaseous refrigerant from the compressor outlet is divided into two paths, one path enters the first heat exchanger through the first port of the four-way reversing valve, and the other path It enters the ejector through the seventh solenoid valve; the liquid refrigerant from the first heat exchanger enters the subcooler for cooling and is divided into two paths. The flow element is throttled into a low-temperature and low-pressure gas-liquid two-phase, and then enters the subcooler, and exchanges heat with the high-temperature refrigerant in the subcooler. The high-temperature and high-pressure gaseous refrigerant mixed with the gaseous refrigerant becomes a gaseous refrigerant, and then passes into the compressor through the one-way valve; and/or,

When the refrigeration system is in the heating cycle using the ejector, the high-temperature and high-pressure gaseous refrigerant from the compressor outlet is divided into two paths, one of which enters the second heat exchanger through the first port of the four-way reversing valve, and the other One way enters the ejector through the seventh solenoid valve; the liquid refrigerant from the second heat exchanger enters the subcooler for cooling and is divided into two ways, one way is throttled by the first throttling element and then enters the first heat exchanger through the second solenoid valve. In the heater, the other path is throttled by the second throttling element into a low-temperature and low-pressure gas-liquid two-phase, and then enters the subcooler, and exchanges heat with the high-temperature refrigerant in the subcooler, and then enters the subcooler through the subcooling interface of the ejector. The ejector is mixed with the high-temperature and high-pressure gaseous refrigerant sucked in the ejector to become a gaseous refrigerant, and then passes through the one-way valve to the compressor.

Further, the present invention also provides a control method for an ejector subcooled refrigeration system, wherein the refrigeration system includes a working condition with an ejector and a working condition without an ejector; the working condition without an ejector includes:

When the refrigeration system is in the non-evacuator refrigeration cycle, the high-temperature and high-pressure gaseous refrigerant from the compressor outlet passes through the first port of the four-way reversing valve and enters the first heat exchanger for condensation; After being throttled by the first throttling element, the liquid refrigerant becomes a low-temperature and low-pressure gas-liquid two-phase refrigerant, and then enters the second heat exchanger for isobaric evaporation into superheated vapor, and finally enters the compressor to be compressed into high-temperature and high-pressure refrigeration. agent;

When the refrigeration system is in the heating cycle condition without the use of the ejector, the high-temperature and high-pressure gaseous refrigerant from the outlet of the compressor enters the second heat exchanger through the first port of the four-way reversing valve for condensation; the second heat exchanger The outgoing liquid refrigerant enters the first heat exchanger through the first throttling element for isobaric evaporation into superheated vapor, and then enters the compressor to be compressed into high temperature and high pressure refrigerant.

The solution provided by the present invention, compared with the traditional refrigeration cycle, when the refrigeration system is a cycle using an ejector, because the subcooler increases the subcooling degree of the liquid refrigerant, the refrigeration capacity is improved; The outgoing gas enters the compressor, which increases the power consumption of the compressor. However, according to the existing technology of increasing the enthalpy of jet, the increase in the cooling capacity is far greater than the power consumption of the compressor, so the system provided by the present invention Reasonable design with the ejector can ensure that the energy efficiency ratio COP can be improved, so that the performance of the refrigeration system can be improved and more energy-saving; and when the operating conditions of the entire refrigeration system are not conducive to the cycle operation of the ejector, it can be switched to the conventional cycle.

Description of drawings

The present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

The present invention will be further described below in conjunction with the accompanying drawings:

Fig. 1 is a kind of refrigeration system schematic diagram of ejection subcooling of the present invention;

FIG. 2 is a schematic diagram of the refrigeration cycle principle of an ejector subcooling refrigeration system without an ejector according to the present invention;

FIG. 3 is a schematic diagram of the heating cycle principle of an ejector subcooling refrigeration system without an ejector according to the present invention;

FIG. 4 is a schematic diagram of the refrigeration cycle principle of an ejector subcooling refrigeration system using an ejector according to the present invention;

FIG. 5 is a schematic diagram of a heating cycle principle of an ejector subcooling refrigeration system using an ejector according to the present invention.

In the figure: 1, compressor; 2, first heat exchanger; 3, ejector; 4, subcooler; 5, second throttle element; 6, first throttle element; 7, second heat exchange 8, the first solenoid valve; 9, the second solenoid valve; 10, the third solenoid valve; 11, the fourth solenoid valve; 12, the fifth solenoid valve; 13, the sixth solenoid valve; 14, the seventh solenoid valve ; 15, four-way reversing valve; 16, one-way valve; 17, ejector subcooling interface; 18, the first branch; 19, the second branch; 20, the third branch; 21, the fourth branch Road; 22, Fifth Branch Road; 23, Sixth Branch Road; 24, Seventh Branch Road; 25, Eighth Branch Road; 26, Ninth Branch Road; 27, Tenth Branch Road; 28, Eleventh Branch road.

Detailed ways

It should be noted that the embodiments in the present application and the features of the embodiments may be combined with each other in the case of no conflict. The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

As shown in FIG. 1 to FIG. 5 , the present invention provides a refrigeration system for induced subcooling, which specifically includes a compressor 1, a first heat exchanger 2, a first throttle element 6, a second heat exchanger 7 and four Reversing valve 15; wherein, the outlet of the compressor 1 communicates with the first port of the four-way reversing valve 15, the second port of the four-way reversing valve 15 communicates with one end of the first heat exchanger 2, and the first The other end of the heat exchanger 2 communicates with the first throttle element 6 through the first branch 18, and the other end of the first throttle element 6 communicates with the first end of the second heat exchanger 7 through the second branch 19, The other end of the second heat exchanger 7 is communicated with the third port of the four-way reversing valve 15, and the fourth port of the four-way reversing valve 15 is communicated with the air inlet of the compressor 1, thereby forming a refrigeration cycle; further , the refrigeration system also includes an ejector 3 and a subcooler 4; wherein, the inlet end of the ejector 3 communicates with the air outlet of the compressor 1 through the third branch 20, and the outlet end of the ejector 3 passes through the fourth branch Road 21 communicates with the air inlet of compressor 1, the inlet end of subcooler 4 communicates with the first heat exchanger 2 through the fifth branch 22, and the inlet end of the subcooler 4 also communicates with the first heat exchanger 2 through the sixth branch 23. The second heat exchanger 7 is communicated; the first outlet end of the subcooler 4 is also communicated with the ejector subcooling interface 17 of the ejector 3 through the seventh branch 24, and the second outlet end of the subcooler 4 also communicates with the ejector subcooling interface 17 of the ejector 3 through the seventh branch 24. The eight branches 25 are communicated with the first throttling element 6; the above solution is adopted, so that the refrigeration system can be started during the cooling or heating process and use the ejector 3 and the subcooler 4 for heat exchange, increasing the liquid refrigeration The subcooling degree of the agent can be improved, so that the cooling capacity can be improved, which can ensure that the energy efficiency ratio COP can be improved, so that the performance of the refrigeration system can be improved and more energy-saving; at the same time, the ejector can be turned off during the cooling or heating process. 3 and subcooler 4, operate with conventional refrigeration or heating cycles, to avoid using the operating conditions of the refrigeration system, which is not conducive to the cycle operation of the ejector; the two modes can be switched freely, making the operation of the refrigeration system more stable and reasonable .

Preferably, in combination with the above solutions, as shown in FIGS. 1 to 5 , a heat exchange tube is provided between the inlet end and the second outlet end of the subcooler 4 , and the heat exchange tube is connected to the high-temperature refrigerant in the subcooler 4 . Perform heat exchange, that is, the refrigerant in the heat exchange tube can exchange heat with the high-temperature refrigerant in the subcooler 4; further, the second outlet end of the subcooler 4 communicates with the subcooler 4 through the tenth branch 27 Internal communication; the tenth branch 27 is provided with a second throttling element 5, so that the liquid refrigerant in the tenth branch 27 from the subcooler 4 is throttled into a low-temperature and low-pressure gas through the second throttling element 5 The liquid two-phase enters the subcooler 4 and exchanges heat with the high-temperature refrigerant in the tube; further, the second branch 19 communicates with the first heat exchanger 2 through the ninth branch 26, and the second branch 19 is located on the A sixth solenoid valve 13 is provided between the connection port of the ninth branch 26 and the second heat exchanger 7 , so that the refrigerant from the first throttling element 6 can enter the first heat exchange through the ninth branch 26 In the device 2 , it is not affected by the sixth solenoid valve 13 , and at the same time, it is also avoided that the refrigerant on the sixth branch 23 is not affected by the first throttle element 6 during the heating process.

Preferably, in combination with the above solutions, as shown in FIGS. 1 to 5 , in this embodiment, the third branch 20 is provided with a seventh solenoid valve 14 , the fourth branch 21 is provided with a check valve 16 , and the refrigeration system According to the opening and closing of the seventh solenoid valve 14, the switching between the working condition of using the ejector and the working condition of not using the ejector is realized, and the entire refrigeration system is turned on to use the ejector 3 and the subcooler 4 for heat exchange At this time, the high-temperature and high-pressure refrigerant from the outlet of compressor 1 is divided into two paths, one of which can enter the ejector 3 through the seventh solenoid valve 14 on the third branch 20, and the low-temperature refrigerant inhaled at the subcooling interface 17 of the ejector After the low-pressure gaseous refrigerant is evenly mixed, it becomes a gaseous refrigerant of intermediate pressure, and then passes into the compressor 1 through the one-way valve 16, and is compressed into a high-temperature and high-pressure refrigerant superheated vapor and then discharged, thereby completing a cycle process; When the entire refrigeration system does not open the ejector 3 and the subcooler 4 for heat exchange, the refrigeration system can operate according to the conventional refrigeration and heating conditions, which can effectively interfere with the refrigeration system under different operating conditions.

Preferably, in combination with the above solutions, as shown in FIG. 1 to FIG. 5 , the refrigeration system further includes an eleventh branch 28 , and one end of the eleventh branch 28 is connected to the fifth branch 22 and the sixth branch 23 respectively, wherein , the other end of the eleventh branch 28 communicates with the inlet end of the subcooler 4; the eleventh branch 28 is provided with a fourth solenoid valve 11, and the fifth branch 22 is provided with a first solenoid valve 8; the sixth The branch 23 is provided with the fifth solenoid valve 12. The opening of the first solenoid valve 8 is mainly for heat exchange during the refrigeration working condition using the ejector 3 and the subcooler 4 for the entire refrigeration system. It is mainly turned on to exchange heat during the heating condition using the ejector 3 and the subcooler 4 for the entire refrigeration system.

Preferably, in combination with the above solutions, as shown in FIGS. 1 to 5 , one end of the sixth branch 23 is connected to the second branch 19 , and the interface between the sixth branch 23 and the second branch 19 is located between the sixth solenoid valve 13 and the second branch 19 . The design between the second heat exchangers 7 is such that the entire refrigeration system will not be affected by the first throttling element 6 during the heating condition using the ejector 3 and the subcooler 4 .

Preferably, in combination with the above solutions, as shown in FIGS. 1 to 5 , when the refrigeration system is in the working condition of using the ejector refrigeration cycle, the first solenoid valve 8 , the seventh solenoid valve 14 , the fourth solenoid valve 11 and the sixth solenoid valve The solenoid valve 13 is in the open state, the second solenoid valve 9, the third solenoid valve 10 and the fifth solenoid valve 12 are in the closed state; the high-temperature and high-pressure gaseous refrigerant coming out of the air outlet of the compressor 1 is divided into two paths, and one path is replaced by a four-way switch. The first port of the valve 15 enters the first heat exchanger 2 and is condensed into liquid at the same pressure, and the other way enters the ejector 3 through the seventh solenoid valve 14; the liquid refrigerant from the first heat exchanger 2 enters the subcooler 4 After cooling, it is divided into two paths. One path is throttling by the first throttling element 6 and becomes a low-temperature and low-pressure gas-liquid two-phase. It enters the second heat exchanger 7 for isobaric evaporation into superheated vapor, and then enters the compressor 1 and compresses into a superheated vapor. The high-temperature and high-pressure refrigerant superheated vapor is discharged, and the other path from the subcooler 4 is throttled into a low-temperature and low-pressure gas-liquid two-phase through the second throttling element 5, and then flows back into the subcooler 4, and is combined with the subcooler 4. The high-temperature refrigerant inside exchanges heat, and then enters the ejector 3 through the ejector subcooling interface 17, and is mixed with the high-temperature and high-pressure gaseous refrigerant sucked in the ejector 3 to become a gaseous refrigerant, and then passes through the one-way valve. 16 is passed into the compressor 1; specifically, because the second throttling element 5 is throttled into a low-temperature and low-pressure gas-liquid two-phase and then flows back into the subcooler 4 and the high-temperature refrigerant in the subcooler 4 tube for heat exchange, absorbing heat. Because the pressure at the ejector subcooling port 17 of the ejector 3 is very low, the gaseous refrigerant is sucked into the ejector 3 from the ejector subcooling port 17 due to the pressure difference, and the compressor 1 exits. The other branch high temperature and high pressure gaseous refrigerant at the place enters the ejector 3, and in the ejector 3, after being evenly mixed with the low temperature and low pressure gaseous refrigerant inhaled from the subcooling interface 17 of the ejector, it becomes an intermediate pressure refrigerant. The gaseous refrigerant is passed into the compressor 1, compressed into a high temperature and high pressure refrigerant superheated vapor and then discharged, thereby completing a cycle process.

Preferably, in combination with the above solutions, as shown in FIG. 1 to FIG. 5 , when the refrigeration system is in the heating cycle using the ejector, the seventh solenoid valve 14 , the fifth solenoid valve 12 , the fourth solenoid valve 11 and the The second solenoid valve 9 is in an open state, and the first solenoid valve 8, the third solenoid valve 10, and the sixth solenoid valve 13 are in a closed state; the high-temperature and high-pressure gaseous refrigerant coming out of the air outlet of the compressor 1 is divided into two paths, one of which passes through the four-way The first port of the reversing valve 15 enters the second heat exchanger 7 and condenses into liquid at equal pressure, and the other way enters the ejector 3 through the seventh solenoid valve 14; the liquid refrigerant from the second heat exchanger 7 enters the subcooling After the tube of the heat exchanger 4 is cooled, it is divided into two paths, one of which becomes a low-temperature and low-pressure gas-liquid two-phase through the first throttling element 6 after equal enthalpy throttling, and then enters the first heat exchanger 2 through the second solenoid valve 9 for processing, etc. pressure evaporated into superheated vapor, and then enter the compressor 1 to be compressed into high temperature and high pressure refrigerant superheated vapor and then discharged; the other path from the subcooler 4 is throttled into a low temperature and low pressure gas-liquid two-phase through the second throttling element 5 Enter the subcooler 4, and exchange heat with the high temperature refrigerant in the subcooler 4, enter the ejector 3 through the ejector subcooling interface 17, and mix with the high temperature and high pressure gaseous refrigerant inhaled in the ejector 3 It becomes a gaseous refrigerant, and then passes through the one-way valve 16 into the compressor 1; specifically, the liquid refrigerant in another branch from the subcooler 4 is throttled into a low-temperature and low-pressure gas-liquid through the second throttling element 5 After two phases, it enters the subcooler 4, and exchanges heat with the high-temperature refrigerant in the tube of the subcooler 4. The gaseous refrigerant after heat absorption is because the pressure at the ejector subcooling interface 17 of the ejector 3 is very low. The pressure difference is sucked into the ejector 3 from the ejector subcooling interface 17, and another branch high temperature and high pressure gaseous refrigerant at the outlet of the compressor 1 enters the ejector 3, and is in the ejector 3 with the refrigerant. After the low-temperature and low-pressure gaseous refrigerant sucked from the subcooling port 17 of the ejector is mixed evenly, it becomes a gaseous refrigerant of intermediate pressure, passes into the compressor 1, is compressed into a high-temperature and high-pressure refrigerant superheated vapor, and is discharged, thereby Complete a cycle process.

Preferably, in combination with the above solutions, as shown in FIG. 1 to FIG. 5 , in the refrigeration system solution of the ejector subcooling provided by the present invention, the refrigeration system is in the refrigeration cycle using the ejector and the refrigeration system is in the system using the ejector. The thermal cycle conditions can be determined according to the activation of the first solenoid valve 8 , the second solenoid valve 9 , the third solenoid valve 10 , the fourth solenoid valve 11 , the fifth solenoid valve 12 , the sixth solenoid valve 13 , and the seventh solenoid valve 14 . It can be switched off by closing, so as to better match the most reliable operation of the refrigeration system in the actual working conditions, effectively increase the cooling capacity, and ensure that the energy efficiency ratio COP is improved, thereby improving the performance of the refrigeration system.

Preferably, in combination with the above solutions, as shown in FIG. 1 to FIG. 5 , when the refrigeration system is in a refrigeration working condition, the first heat exchanger 2 is a condenser, and the second heat exchanger 7 is an evaporator; specifically: a compressor 1 The high-temperature and high-pressure gaseous refrigerant from the air outlet enters the first heat exchanger 2 for condensation through the first port of the four-way reversing valve 15; the liquid refrigerant from the first heat exchanger 2 passes through the first throttling element 6 sections. After flowing, it becomes a low-temperature and low-pressure gas-liquid two-phase refrigerant, and then enters the second heat exchanger 7 for isobaric evaporation into superheated vapor, and finally enters the compressor 1 to be compressed into a high-temperature and high-pressure refrigerant; when the refrigeration system is in the heating process In this case, the first heat exchanger 2 is an evaporator, and the second heat exchanger 7 is a condenser; specifically: the high-temperature and high-pressure gaseous refrigerant from the air outlet of the compressor 1 passes through the first port of the four-way reversing valve 15 Enter the second heat exchanger 7 for condensation; the liquid refrigerant from the second heat exchanger 7 enters the first heat exchanger 2 through the first throttling element 6 for isobaric evaporation into superheated vapor, and then enters the compressor 1 and is compressed into High temperature and high pressure refrigerant; further, both the first throttling element 6 and the second throttling element 5 can be throttling elements such as an electronic expansion valve, a thermal expansion valve or a capillary tube.

Correspondingly, in combination with the above solutions, as shown in FIG. 1 to FIG. 5 , the present invention also provides a control method for a refrigeration system with induced subcooling, which is applied to the refrigeration system described above; wherein the refrigeration system includes using The ejector working condition and the non-using ejector working condition, and the two working conditions of using the ejector and the non-using ejector working condition in the refrigeration system can be switched, and the two modes can be switched freely. The operation of the refrigeration system is made more stable and reasonable; specifically, the working conditions of using the ejector include:

When the refrigeration system is in the condition of using the ejector refrigeration cycle, the high-temperature and high-pressure gaseous refrigerant from the outlet of the compressor 1 is divided into two paths, one of which enters the first heat exchanger 2 through the first port of the four-way reversing valve 15 The liquid refrigerant is condensed into liquid at equal pressure, and the other way enters the ejector 3 through the seventh solenoid valve 14; the liquid refrigerant from the first heat exchanger 2 enters the subcooler 4 for cooling and is divided into two ways, and one way passes through the first throttling element 6 After constant enthalpy throttling, the gas-liquid two-phase of low temperature and low pressure enters the second heat exchanger 7 for isobaric evaporation into superheated vapor, and then enters the compressor 1 to be compressed into high temperature and high pressure refrigerant superheated vapor and then discharged from the subcooler. The other way out of 4 passes through the second throttling element 5 and is throttled into a low-temperature and low-pressure gas-liquid two-phase, and then flows back into the subcooler 4, and exchanges heat with the high-temperature refrigerant in the subcooler 4, and then passes through the ejector. The cold port 17 enters the ejector 3 and is mixed with the high-temperature and high-pressure gaseous refrigerant sucked in the ejector 3 to become a gaseous refrigerant, and then passes into the compressor 1 through the one-way valve 16; The throttling element 5 is throttled into low-temperature and low-pressure gas-liquid two-phase, and then flows back into the subcooler 4 and the high-temperature refrigerant in the tube of the subcooler 4 for heat exchange. The pressure at the subcooling port 17 is very low, and is sucked into the ejector 3 from the subcooling port 17 of the ejector due to the pressure difference, and the high temperature and high pressure gaseous refrigerant at the outlet of the compressor 1 enters the ejector After being mixed evenly with the low-temperature and low-pressure gaseous refrigerant sucked from the subcooling interface 17 of the ejector in the ejector 3, it becomes a gaseous refrigerant of intermediate pressure, which is passed into the compressor 1 and is compressed into The high-temperature and high-pressure refrigerant superheated vapor is discharged to complete a cycle; and/or,

When the refrigeration system is in the heating cycle using the ejector, the high-temperature and high-pressure gaseous refrigerant from the outlet of the compressor 1 is divided into two paths, one of which enters the second heat exchanger through the first port of the four-way reversing valve 15 7 Condenses into liquid at equal pressure, and the other way enters the ejector 3 through the seventh solenoid valve 14; the liquid refrigerant from the second heat exchanger 7 enters the tube of the subcooler 4 and is cooled in two ways, one way through the first The throttling element 6 becomes a low-temperature and low-pressure gas-liquid two-phase after constant enthalpy throttling, and then enters the first heat exchanger 2 through the second solenoid valve 9 for isobaric evaporation into superheated steam, and then enters the compressor 1 to compress to a high temperature The high-pressure refrigerant is discharged after superheated vapor; the other path from the subcooler 4 is throttled through the second throttling element 5 into a low-temperature and low-pressure gas-liquid two-phase, and then enters the subcooler 4, and is connected with the refrigerant in the subcooler 4. After heat exchange, the high-temperature refrigerant enters the ejector 3 through the ejector subcooling interface 17, and is mixed with the high-temperature and high-pressure gaseous refrigerant sucked in the ejector 3 to become a gaseous refrigerant, and then passes through the check valve 16. Compressor 1; Specifically, the liquid refrigerant in another branch from the subcooler 4 is throttled into a low-temperature and low-pressure gas-liquid two-phase through the second throttling element 5, and then enters the subcooler 4, and is connected with the subcooler. 4. The high temperature refrigerant in the tube exchanges heat, and the gaseous refrigerant after absorbing heat is sucked from the subcooling port 17 of the ejector due to the pressure difference because the pressure at the subcooling port 17 of the ejector 3 is very low. In the ejector 3, another branch high-temperature and high-pressure gaseous refrigerant at the outlet of the compressor 1 enters the ejector 3, and in the ejector 3, it interacts with the low-temperature and low-pressure gaseous refrigerant sucked from the subcooling interface 17 of the ejector. After the refrigerant is mixed evenly, it becomes a gaseous refrigerant of intermediate pressure, passes into the compressor 1, is compressed into a superheated vapor of the refrigerant with high temperature and high pressure, and is discharged, thereby completing a cycle process.

Preferably, in combination with the above solutions, as shown in FIG. 1 to FIG. 5 , the present invention further provides a method for controlling a refrigeration system with ejection of subcooling, which is applied to the above refrigeration system; wherein the refrigeration system includes using Ejector working condition and non-using ejector working condition; non-using ejector working condition includes:

When the refrigeration system is in the non-evacuator refrigeration cycle condition, the high-temperature and high-pressure gaseous refrigerant from the outlet of the compressor 1 enters the first heat exchanger 2 through the first port of the four-way reversing valve 15 for condensation; the first The liquid refrigerant from the heat exchanger 2 becomes a low-temperature and low-pressure gas-liquid two-phase refrigerant after being throttled by the first throttling element 6, and then enters the second heat exchanger 7 for isobaric evaporation into superheated vapor, and finally enters the compression process. Machine 1 is compressed into a high temperature and high pressure refrigerant;

When the refrigeration system is in the heating cycle without the use of the ejector, the high-temperature and high-pressure gaseous refrigerant from the outlet of the compressor 1 enters the second heat exchanger 7 through the first port of the four-way reversing valve 15 for condensation; The liquid refrigerant from the second heat exchanger 7 enters the first heat exchanger 2 through the first throttling element 6 for isobaric evaporation into superheated vapor, and then enters the compressor 1 to be compressed into a high temperature and high pressure refrigerant.

Using the above scheme, by combining the conventional vapor compression cycle and the ejector subcooling cycle, the above two working modes are switched by judging the working conditions, so as to ensure that the cycle achieves an efficient energy efficiency ratio, and also enables the ejector to avoid unstable operating conditions.

The solution provided by the present invention, compared with the traditional refrigeration cycle, when the refrigeration system is a cycle using an ejector, because the subcooler increases the subcooling degree of the liquid refrigerant, the refrigeration capacity is improved; The outgoing gas enters the compressor, which increases the power consumption of the compressor. However, according to the existing technology of increasing the enthalpy of jet, the increase in the cooling capacity is far greater than the power consumption of the compressor, so the system provided by the present invention Reasonable design with the ejector can ensure that the energy efficiency ratio COP can be improved, so that the performance of the refrigeration system can be improved and more energy-saving; and when the operating conditions of the entire refrigeration system are not conducive to the cycle operation of the ejector, it can be switched to the conventional cycle.

The above descriptions are only preferred embodiments of the present invention, and do not limit the present invention in any form. Any person skilled in the art, without departing from the scope of the technical solution of the present invention, can use the above-mentioned technical content to make many possible changes and modifications to the technical solution of the present invention, or be modified to equivalent embodiments of equivalent changes. . Therefore, any modifications, equivalent changes and modifications made to the above embodiments according to the technology of the present invention without departing from the content of the technical solution of the present invention all belong to the protection scope of the technical solution of the present invention.

Claims (10)

1. A refrigeration system for injection supercooling comprises a compressor (1), a first heat exchanger (2), a first throttling element (6), a second heat exchanger (7) and a four-way reversing valve (15); the air outlet of the compressor (1) is communicated with a first port of the four-way reversing valve (15), a second port of the four-way reversing valve (15) is communicated with one end of the first heat exchanger (2), the other end of the first heat exchanger (2) is communicated with the first throttling element (6) through a first branch (18), the other end of the first throttling element (6) is communicated with a first end of the second heat exchanger (7) through a second branch (19), the other end of the second heat exchanger (7) is communicated with a third port of the four-way reversing valve (15), and a fourth port of the four-way reversing valve (15) is communicated with the air inlet of the compressor (1); the refrigeration system is characterized by also comprising an ejector (3) and a subcooler (4); the inlet end of the ejector (3) is communicated with the air outlet of the compressor (1) through a third branch (20), and the outlet end of the ejector (3) is communicated with the air inlet of the compressor (1) through a fourth branch (21); the inlet end of the subcooler (4) is communicated with the first heat exchanger (2) through a fifth branch (22), and the inlet end of the subcooler (4) is also communicated with the second heat exchanger (7) through a sixth branch (23); the first outlet end of the subcooler (4) is communicated with an ejector subcooling interface (17) of the ejector (3) through a seventh branch (24), and the second outlet end of the subcooler (4) is communicated with the first throttling element (6) through an eighth branch (25).

2. The refrigeration system for injecting supercooling according to claim 1, wherein a heat exchange pipe is arranged between the inlet end and the second outlet end of the subcooler (4); the heat exchange tube exchanges heat with a high-temperature refrigerant in the subcooler (4); the second outlet end of the subcooler (4) is communicated with the inside of the subcooler (4) through a tenth branch (27); a second throttling element (5) is arranged on the tenth branch (27); the second branch (19) communicates with the first heat exchanger (2) via a ninth branch (26); and a sixth electromagnetic valve (13) is arranged on the second branch (19) and between the ninth branch (26) connecting port and the second heat exchanger (7).

3. The injection subcooling refrigeration system as described in claim 1, wherein a seventh solenoid valve (14) is provided in the third branch (20), and a check valve (16) is provided in the fourth branch (21); the refrigerating system realizes the switching between the working condition of using the ejector and the working condition of not using the ejector according to the opening and closing of the seventh electromagnetic valve (14).

4. The refrigeration system for injection subcooling as claimed in claim 2, further comprising an eleventh branch (28), wherein one end of the eleventh branch (28) is respectively communicated with the fifth branch (22) and the sixth branch (23), and the other end of the eleventh branch (28) is communicated with the inlet end of the subcooler (4); a fourth electromagnetic valve (11) is arranged on the eleventh branch (28), and a first electromagnetic valve (8) is arranged on the fifth branch (22); and a fifth electromagnetic valve (12) is arranged on the sixth branch (23).

5. The injection subcooling refrigeration system as recited in claim 4, characterized in that the sixth branch (23) is connected at one end to the second branch (19) and the connection of the sixth branch (23) to the second branch (19) is between the sixth solenoid valve (13) and the second heat exchanger (7).

6. The refrigeration system for injection subcooling as described in claim 5, wherein when the refrigeration system is in an ejector refrigeration cycle, the first solenoid valve (8), the seventh solenoid valve (14), the fourth solenoid valve (11) and the sixth solenoid valve (13) are in an open state, and the second solenoid valve (9), the third solenoid valve (10) and the fifth solenoid valve (12) are in a closed state; the high-temperature and high-pressure gaseous refrigerant from the air outlet of the compressor (1) is divided into two paths, wherein one path of the high-temperature and high-pressure gaseous refrigerant enters the first heat exchanger (2) through the first port of the four-way reversing valve (15), and the other path of the high-temperature and high-pressure gaseous refrigerant enters the ejector (3) through the seventh electromagnetic valve (14); the liquid refrigerant coming out of the first heat exchanger (2) enters the subcooler (4) to be cooled and then is divided into two paths, one path of refrigerant enters the second heat exchanger (7) through the first throttling element (6), the other path of refrigerant enters the subcooler (4) after being throttled into low-temperature and low-pressure gas-liquid two phases through the second throttling element (5), exchanges heat with the high-temperature refrigerant in the subcooler (4) and then enters the ejector (3) through the ejector supercooling connector (17), is mixed with the high-temperature and high-pressure gaseous refrigerant sucked in the ejector (3) to become the gaseous refrigerant, and then is introduced into the compressor (1) through the one-way valve (16).

7. The refrigeration system for injection subcooling as described in claim 5, wherein when the refrigeration system is in an ejector heating cycle, the seventh solenoid valve (14), the fifth solenoid valve (12), the fourth solenoid valve (11) and the second solenoid valve (9) are in an open state, and the first solenoid valve (8), the third solenoid valve (10) and the sixth solenoid valve (13) are in a closed state; the high-temperature and high-pressure gaseous refrigerant from the air outlet of the compressor (1) is divided into two paths, wherein one path of the high-temperature and high-pressure gaseous refrigerant enters the second heat exchanger (7) through the first port of the four-way reversing valve (15), and the other path of the high-temperature and high-pressure gaseous refrigerant enters the ejector (3) through the seventh electromagnetic valve (14); the liquid refrigerant coming out of the second heat exchanger (7) enters the subcooler (4) to be cooled and then is divided into two paths, one path of refrigerant passes through the first throttling element (6) to be throttled and then enters the first heat exchanger (2) through the second electromagnetic valve (9), the other path of refrigerant passes through the second throttling element (5) to be throttled into low-temperature low-pressure gas-liquid two phases and then enters the subcooler (4), exchanges heat with the high-temperature refrigerant in the subcooler (4) and then enters the ejector (3) through the ejector connector (17), is mixed with the high-temperature high-pressure gaseous refrigerant sucked in the ejector (3) to become gaseous refrigerant, and then is introduced into the compressor (1) through the one-way valve (16).

8. The injection subcooling refrigeration system as described in any one of claims 1 to 7, wherein when the refrigeration system is in a refrigeration condition, the first heat exchanger (2) is a condenser and the second heat exchanger (7) is an evaporator; when the refrigerating system is in a heating working condition, the first heat exchanger (2) is an evaporator, and the second heat exchanger (7) is a condenser; and/or the first throttling element is an electronic expansion valve, a thermal expansion valve or a capillary tube.

9. A control method of a refrigeration system for injection supercooling, which is applied to the refrigeration system of any one of the above claims 1 to 8; the refrigerating system is characterized by comprising an ejector using working condition and an ejector non-using working condition, wherein the ejector using working condition and the ejector non-using working condition in the refrigerating system can be switched; the operating conditions of the ejector include:

when the refrigerating system is in a working condition of using an ejector for refrigerating circulation, high-temperature and high-pressure gaseous refrigerant from the air outlet of the compressor (1) is divided into two paths, wherein one path of the high-temperature and high-pressure gaseous refrigerant enters the first heat exchanger (2) through the first port of the four-way reversing valve (15), and the other path of the high-temperature and high-pressure gaseous refrigerant enters the ejector (3) through the seventh electromagnetic valve (14); liquid refrigerant from the first heat exchanger (2) enters the subcooler (4) to be cooled and then is divided into two paths, wherein one path of refrigerant enters the second heat exchanger (7) through the first throttling element (6), the other path of refrigerant is throttled into a low-temperature low-pressure gas-liquid two-phase refrigerant through the second throttling element (5) and then enters the subcooler (4), exchanges heat with high-temperature refrigerant in the subcooler (4), enters the ejector (3) through the ejector subcooling interface (17), is mixed with high-temperature high-pressure gaseous refrigerant sucked in the ejector (3) to become gaseous refrigerant, and is introduced into the compressor (1) through the one-way valve (16); and/or the presence of a gas in the gas,

when the refrigerating system is in a heating cycle working condition by using an ejector, the high-temperature and high-pressure gaseous refrigerant from the air outlet of the compressor (1) is divided into two paths, one path of the high-temperature and high-pressure gaseous refrigerant enters the second heat exchanger (7) through the first port of the four-way reversing valve (15), and the other path of the high-temperature and high-pressure gaseous refrigerant enters the ejector (3) through the seventh electromagnetic valve (14); the liquid refrigerant coming out of the second heat exchanger (7) enters the subcooler (4) to be cooled and then is divided into two paths, one path of refrigerant passes through the first throttling element (6) to be throttled and then enters the first heat exchanger (2) through the second electromagnetic valve (9), the other path of refrigerant passes through the second throttling element (5) to be throttled into low-temperature low-pressure gas-liquid two phases and then enters the subcooler (4), exchanges heat with the high-temperature refrigerant in the subcooler (4) and then enters the ejector (3) through the ejector connector (17), is mixed with the high-temperature high-pressure gaseous refrigerant sucked in the ejector (3) to become gaseous refrigerant, and then is introduced into the compressor (1) through the one-way valve (16).

10. A method of controlling an ejector subcooling refrigeration system according to claim 9, wherein the non-use ejector operating conditions include:

when the refrigerating system is in a non-use ejector refrigeration cycle working condition, high-temperature and high-pressure gaseous refrigerant from the air outlet of the compressor (1) enters the first heat exchanger (2) through the first port of the four-way reversing valve (15) to be condensed; the liquid refrigerant from the first heat exchanger (2) is throttled by the first throttling element (6) and then changed into a low-temperature and low-pressure gas-liquid two-phase refrigerant, and then enters the second heat exchanger (7) to be subjected to isobaric evaporation to obtain superheated steam, and finally enters the compressor (1) to be compressed into a high-temperature and high-pressure refrigerant;

when the refrigerating system is in a non-use ejector heating cycle working condition, high-temperature and high-pressure gaseous refrigerant from the air outlet of the compressor (1) enters the second heat exchanger (7) through the first port of the four-way reversing valve (15) to be condensed; the liquid refrigerant from the second heat exchanger (7) enters the first heat exchanger (2) through the first throttling element (6) to be isobaric evaporated into superheated vapor, and then enters the compressor (1) to be compressed into high-temperature and high-pressure refrigerant.

Images