CN113899095A

CN113899095A - Quasi-two-stage compression type circulating system with ejector for efficiency improvement

Info

Publication number: CN113899095A
Application number: CN202111371560.4A
Authority: CN
Inventors: 陈壮; 赵红霞; 孔繁辰; 哈森; 陈海平
Original assignee: Shandong University
Current assignee: Shandong University
Priority date: 2021-11-18
Filing date: 2021-11-18
Publication date: 2022-01-07
Anticipated expiration: 2041-11-18
Also published as: CN113899095B

Abstract

The invention relates to a quasi-two-stage compression type circulating system with an ejector for synergism, which is a self-laminating compression refrigeration circulating system and comprises a compressor, wherein the compressor is connected with a condenser, the condenser is connected with a first gas-liquid separator, one liquid outlet of the first gas-liquid separator is connected with a first ejector, the first ejector is connected with an air supplementing port of the compressor through a heat passing side of a first heat regenerator, the other liquid outlet of the first gas-liquid separator is connected with an evaporation side inlet of an evaporation condenser through a cold passing side and a pressure reduction and temperature reduction element of the first heat regenerator in sequence, an outlet of the evaporation side is connected with a secondary flow inlet of the first ejector, a gas outlet of the first gas-liquid separator is connected with an evaporator through a second heat regenerator, a condensation side of the evaporation condenser, the second gas-liquid separator and a third heat regenerator, and the evaporator is connected with an air suction port of the compressor through the third heat regenerator, the second ejector and the second heat regenerator, the system of the invention has strong capability of adapting to variable working conditions and small throttling loss.

Description

Quasi-two-stage compression type circulating system with ejector for efficiency improvement

Technical Field

The invention relates to the technical field of vapor compression refrigeration and heat pumps, in particular to a quasi-two-stage compression type circulating system with an ejector for synergism.

Background

The statements herein merely provide background information related to the present disclosure and may not necessarily constitute prior art.

The current compression cycle system includes a compression refrigeration cycle system, a compression heat pump cycle system, and the like.

Aiming at a compression refrigeration cycle system, along with the development of industry and the progress of technology, the fields of biomedicine, food industry, cold chain logistics and the like have new requirements on low-temperature refrigeration technology, and particularly the demand on the temperature region below-40 ℃ is increasingly strong. At present, the ways of implementing the above low-temperature region refrigeration mainly include: single working medium multi-stage compression refrigeration, mixed working medium two-stage cascade refrigeration, mixed working medium self-cascade refrigeration and the like.

The self-cascade refrigerating system is one system with non-azeotropic mixed work medium as refrigerant and one compressor to realize single/multistage fractional condensation and thus lower evaporating temperature. Because of small volume and wide refrigeration temperature range, the refrigerant has wide application prospect in the fields of normal refrigeration and deep refrigeration. However, the conventional self-cascade system has the problems of poor working condition changing capability, serious throttling loss when the evaporation temperature is lower, reduced suction specific volume, reduced gas transmission amount, increased pressure ratio of a compressor and the like, and is difficult to meet the industrial requirements.

In the prior art, chinese patent publication No. CN110762875A discloses a large temperature difference variable component concentration self-cascade heat pump unit, which combines a gas-supplying enthalpy-increasing technology and a self-cascade refrigeration technology together to reduce the pressure ratio and the exhaust temperature of a compressor. However, the inventor finds that under the low-temperature working condition, the throttling loss of the refrigerant is serious, the energy utilization rate is low, the temperature difference between the front and the rear of the compressor is too large, the high-boiling-point refrigerant is easy to liquefy after air supplement and mixing, the liquid impact of the compressor is caused, and the system has poor capability of adapting to variable-working-condition operation.

For a compression heat pump circulating system, a vapor compression type air source heat pump technology is increasingly applied to heat supply of commercial buildings and houses, such as heat pump air conditioners and heat energy water heaters, as an energy-saving, environment-friendly, safe and reliable heating technology. With the improvement of living standard of people, heating in winter increasingly becomes the focus of the civil problem in autumn and winter, and when the traditional steam compression air source heat pump works in a lower outdoor environment at present, the suction specific volume of a compressor is increased, the gas transmission volume is reduced, the pressure ratio of the compressor is increased, the exhaust temperature is overhigh, and the compressor is seriously deviated from the design working condition, so that the energy conservation, the safety and the like of the system are greatly influenced.

In order to enable efficient, safe and stable operation of heat pump systems in low temperature outdoor environments, many improved solutions and solutions have been proposed. At present, a circulation system for supplementing air and increasing enthalpy is adopted, and the circulation system is also called a quasi-two-stage compression circulation system. The compressor of the air source heat pump adopting the air supply enthalpy increasing technology sucks a part of intermediate pressure gas through the intermediate pressure suction hole, and the intermediate pressure gas is mixed with a partially compressed refrigerant and then compressed, so that the single compressor realizes the two-stage compression process, and therefore the air source heat pump adopting the quasi-two-stage compression technology can adapt to the outdoor environment temperature lower than that of a common air source heat pump. However, as the evaporation temperature decreases, irreversible loss of throttling increases, and excessive flash gas enters the evaporator, resulting in a decrease in the effective utilization area of the heat exchanger and an increase in the size of the heat exchanger.

Patent CN110274403A discloses a quasi-two-stage compression cycle system with synergistic ejector, which increases the pressure at the suction port of the compressor and reduces the power consumption of the compressor, but the inventor finds that it is difficult to find a suitable air supply point during variable operation only by adjusting the throttle valve during variable operation and variable load operation.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a quasi-two-stage compression type circulating system with an ejector for synergism, which can ensure the energy conservation and stability of operation under a low-temperature working condition, has certain working condition changing capability and can find a proper air supplementing point when the working condition changes.

In order to achieve the purpose, the invention adopts the following technical scheme

In a first aspect, an embodiment of the invention provides a quasi-two-stage compression type circulation system with an ejector for efficiency enhancement, which is a self-laminating compression type refrigeration circulation system and comprises a compressor, wherein the compressor is connected with a condenser, the condenser is connected with a first gas-liquid separator, one liquid outlet of the first gas-liquid separator is connected with a primary flow inlet of a first ejector, an outlet of the first ejector is connected with an air supplement port of the compressor through a overheating side of a first heat regenerator, the other liquid outlet of the first gas-liquid separator is connected with an evaporation side inlet of an evaporation condenser sequentially through an overheating side of the first heat regenerator and a first pressure and temperature reduction element, and an outlet of the evaporation side is connected with a secondary flow inlet of the first ejector.

Optionally, a stop valve is arranged between the inlet of the superheat side of the first regenerator and the outlet of the first ejector.

Optionally, a condensing side inlet of the evaporative condenser is connected to a gas outlet of the first gas-liquid separator through a cold side of the second heat regenerator, a condensing side outlet of the evaporative condenser is connected to the second gas-liquid separator, a liquid outlet of the second gas-liquid separator is connected to the evaporator, and an outlet of the evaporator is connected to an inlet of the compressor.

Furthermore, a second pressure and temperature reduction element is arranged between the inlet of the second gas-liquid separator and the outlet of the condensation side of the evaporative condenser.

Optionally, a liquid outlet of the second gas-liquid separator is connected to an inlet of the evaporator sequentially through the cold side of the third heat regenerator and the third pressure-reducing and temperature-reducing element, an outlet of the evaporator is connected to a secondary flow inlet of the second ejector through the hot side of the third heat regenerator, and an outlet of the second ejector is connected to an inlet of the compressor through the hot side of the second heat regenerator.

Furthermore, a throttle valve is adopted as a third pressure reduction and temperature reduction element between the supercooling side outlet of the third regenerator and the inlet of the evaporator.

Optionally, the gas outlet of the second gas-liquid separator is connected to the primary flow inlet of the second ejector.

Optionally, a gas outlet of the second gas-liquid separator is connected to a secondary flow inlet of a third ejector, an outlet of the third ejector is connected to a primary flow inlet of the second ejector, a primary flow inlet of the third ejector is connected to a gas outlet of the third gas-liquid separator, an inlet of the third gas-liquid separator is connected to an outlet of the first ejector, and a liquid outlet of the third gas-liquid separator is connected to a superheat side inlet of the first heat regenerator.

Furthermore, stop valves are installed at the inlet, the gas outlet and the liquid outlet of the third gas-liquid separator.

In a second aspect, an embodiment of the present invention provides a quasi-two-stage compression type circulation system with an ejector for efficiency enhancement, which is a compression heat pump circulation system, and includes a compressor, the compressor is connected to a condenser, an outlet of the condenser is connected to a primary flow inlet of a fourth ejector and an inlet of a fourth pressure-reducing and temperature-reducing element, an outlet of the fourth ejector is connected to an air supplement port of the compressor through a fourth gas-liquid separator, an outlet of the fourth pressure-reducing and temperature-reducing element is connected to a fifth gas-liquid separator, and a gas outlet of the fifth gas-liquid separator is connected to a secondary flow inlet of the fourth ejector.

Optionally, a liquid outlet of the fifth gas-liquid separator is connected to a secondary flow inlet of the fifth ejector, a liquid outlet of the fourth gas-liquid separator is connected to a primary flow inlet of the fifth ejector, an outlet of the fifth ejector is connected to an inlet of the evaporator sequentially through a cold passing side of the fourth regenerator and the fifth pressure-reducing and temperature-reducing element, and an outlet of the evaporator is connected to an air suction port of the compressor through a hot passing side of the fourth regenerator.

Optionally, the system further comprises a fifth regenerator, an outlet of the condenser is connected with a supercooling side of the fourth regenerator through a supercooling side of the fifth regenerator, and an outlet of the fourth ejector is connected with the fourth gas-liquid separator through a superheating side of the fifth regenerator.

Optionally, a supercooling side outlet of the fourth regenerator is connected with a sixth gas-liquid separator through a sixth pressure-reducing and temperature-reducing element, a gas outlet of the sixth gas-liquid separator is connected with a fifth gas-liquid separator, and a liquid outlet of the sixth gas-liquid separator is connected with an inlet of the evaporator.

The invention has the beneficial effects that:

1. the compression refrigeration cycle system is provided with the first ejector, the first ejector is matched with the first heat regenerator and the evaporative condenser, air supplement of an air supplement port of the compressor can be realized, the energy saving performance and the stability of the system in operation under a low-temperature working condition can be ensured, and meanwhile, the first ejector is arranged, and a proper air supplement point can be found out when the working condition changes through the structural adjustment of the first ejector, so that the system has certain variable working condition operation capacity.

2. According to the compression refrigeration cycle system, the first heat regenerator, the second heat regenerator and the third heat regenerator are arranged, so that the utilization rate of the system to energy is improved, the temperature gradient in the front and at the back of the compressor can be effectively reduced by overheating the compressor after the compressor sucks air through the second heat regenerator, liquid impact is prevented when air is supplied, and the service life is prolonged.

3. According to the compression refrigeration cycle system, the second ejector is arranged, so that expansion work can be recovered, throttling loss is reduced, the pressure of an air suction port of the compressor is improved, the air suction specific volume is reduced, the air delivery volume is increased, the compressor can still stably work under a low-temperature working condition, and the energy efficiency of the system is improved.

4. The compression refrigeration cycle system is provided with the third ejector and the third gas-liquid separator, when the evaporation temperature is too low, the second ejector can recover expansion work, but the pressure of a suction port of the compressor is still very low, so that the suction specific volume is increased, the gas delivery quantity is reduced, the third ejector is utilized to supplement high-pressure high-boiling-point refrigerant steam into the suction port of the compressor, the pressure of the suction port can be increased, the pressure ratio of the compressor is reduced, the compressor can stably run at lower temperature, and the energy efficiency of the system is improved.

5. The compression heat pump circulating system is provided with the fourth ejector, the fourth gas-liquid separator and the fifth gas-liquid separator, and can be used for supplementing gas to the gas supplementing port of the compressor, so that the enthalpy increase of the gas is realized, the energy saving performance and the stability of the system in operation under the low-temperature working condition can be ensured, and meanwhile, through the structural adjustment of the fourth ejector, a proper gas supplementing point can be found when the working condition changes, so that the system has certain variable working condition operation capacity.

6. The compression heat pump circulating system provided by the invention is provided with the fourth ejector and the fifth ejector, so that the expansion work is recovered to the maximum extent, and the throttling loss is reduced.

7. According to the compression heat pump circulating system, the dryness of the low-temperature refrigerant entering the evaporator can be effectively reduced, the unit refrigerating capacity is improved, and the utilization rate of the area of the evaporator is improved through the arrangement of the fourth heat regenerator and the fifth heat regenerator.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the application and, together with the description, serve to explain the application and are not intended to limit the application.

FIG. 1 is a schematic diagram of the operation of example 1 of the present invention at a temperature of-40 ℃ to-70 ℃;

FIG. 2 is a pressure-enthalpy diagram for the operation of example 1 of the present invention at-40 ℃ to-70 ℃;

FIG. 3 is a schematic diagram of the operation of example 1 of the present invention at a temperature below-70 ℃;

FIG. 4 is a pressure-enthalpy diagram for the operation of example 1 of the present invention at a temperature below-70 ℃;

fig. 5 is a schematic view of embodiment 2 of the present invention operating in a first operation mode;

figure 6 is a pressure-enthalpy diagram for the operation of embodiment 2 of the present invention in the first mode of operation;

fig. 7 is a schematic view of embodiment 2 of the present invention operating in a second operation mode;

figure 8 is a pressure-enthalpy diagram for the operation of embodiment 2 of the present invention in the second mode of operation;

the system comprises a compressor 101, a compressor 102, a condenser 103, a first gas-liquid separator 104, a first ejector 105, a third gas-liquid separator 106, a first heat regenerator 107, an evaporative condenser 108, a second throttle valve 109, a second gas-liquid separator 110, a third heat regenerator 111, a third throttle valve 112, an evaporator 113, a second heat regenerator 114, a third ejector 115, a second ejector 116-1, a third stop valve 116-2, a fourth stop valve 116-3, a second stop valve 116-4, a first stop valve 117, a first throttle valve 118, a fourth ejector 119, a fourth throttle valve 120, a fifth heat regenerator 121, a fourth gas-liquid separator 122, a fifth ejector 123, a fifth gas-liquid separator 124, a fourth heat regenerator 125, a fifth throttle valve 126, a sixth throttle valve 127 and a sixth gas-liquid separator.

Detailed Description

Example 1

The embodiment provides a quasi-two-stage compression refrigeration cycle system with ejector synergy, which is a self-overlapping quasi-two-stage compression refrigeration cycle system with ejector synergy, and as shown in fig. 1, the quasi-two-stage compression refrigeration cycle system with ejector synergy comprises a compressor 101, a condenser 102, an evaporator 112, an evaporative condenser 107, three gas-liquid separators, three ejectors and three regenerators.

In this embodiment, the regenerator may be implemented by using an existing apparatus, and has a superheat side and a subcooling side, in which a to-be-heated working medium flows in from an inlet of the superheat side and flows out from an outlet of the superheat side, and a to-be-cooled working medium flows in from an inlet of the subcooling side and flows out from an outlet of the subcooling side.

The overheating side in the heat regenerator means that a working medium flows into the heat regenerator from an inlet of the overheating side, flows out of the heat regenerator from an outlet of the overheating side, heat exchange is generated in the heat regenerator, and the temperature of the working medium is increased.

The supercooling side in the heat regenerator means that a working medium flows into the supercooling side from an inlet of the supercooling side and then flows out from an outlet of the supercooling side, and the working medium exchanges heat in the heat regenerator to reduce the temperature.

The evaporative condenser 112 may be any conventional device, and has an evaporation side and a condensation side, the evaporation side is a side where the inflowing working medium is heated from a liquid or two-phase working medium to a gas state, and the condensation side is a side where the inflowing working medium releases heat and is changed from a gas state to a liquid state.

The gas-liquid separator can be realized by adopting the existing equipment, and can perform gas-liquid separation on the inflowing working medium.

The ejector is an existing ejector, and can convert the pressure of an inflowing working medium into flowing kinetic energy of the working medium.

An air outlet of the compressor 101 is connected with an inlet of a condenser 102 through a pipeline, and an outlet of the condenser 102 is connected with an inlet of a first gas-liquid separator 103 through a pipeline.

The first gas-liquid separator has one inlet, one gas outlet and two liquid outlets.

One of the liquid outlets of the first gas-liquid separator 103 is connected to the primary flow inlet of the first ejector 104 through a pipeline, the outlet of the first ejector 104 is connected to the inlet of the superheat side of the first heat regenerator 106 through a pipeline, and the outlet of the superheat side of the first heat regenerator 106 is connected to the air make-up port of the compressor 101 through an air make-up pipeline.

Wherein, a first stop valve 116-4 is installed on the pipeline between the outlet pipeline of the first ejector 104 and the superheat side inlet of the first heat regenerator 106, and the first stop valve 116-4 is used for controlling the conduction and the closing of the pipeline.

The other liquid outlet of the first gas-liquid separator 103 is connected to the inlet of the over-cooled side of the first heat regenerator 106, the outlet of the over-cooled side of the first heat regenerator 106 is connected to the inlet of the evaporation side of the evaporative condenser 107 through a pipeline, and a first pressure-reducing and temperature-reducing element is installed on the pipeline between the outlet of the over-cooled side of the first heat regenerator 106 and the inlet of the evaporation side of the evaporative condenser 107, and the first pressure-reducing and temperature-reducing element adopts a first throttle valve 117, so that the pressure and the temperature of the fluid flowing inside the pipeline can be reduced. So that the gas temperature generated after the evaporative condenser 107 evaporates the liquid is lower than the temperature of the liquid in the over-cooled side of the first regenerator 106.

The evaporation side outlet of the evaporative condenser 107 is connected to the secondary flow inlet of the first ejector 104 via a pipe.

In the present embodiment, as shown in fig. 2, the mixed refrigerant flowing out from the outlet of the compressor 101 releases heat at a constant pressure (1-2) in the condenser 102, the refrigerant with a high boiling point is condensed into liquid (state point 4), and the refrigerant with a low boiling point maintains a superheated vapor state (state point 3). The two refrigerants are separated in the first gas-liquid separator 103.

The high boiling point rich refrigerant liquid is split into two branches, one of which passes through the first ejector 104 to convert the pressure energy into kinetic energy (state point 4-4') to eject the gas from the evaporative condenser 107 (state point 9). The other path of the refrigerant passes through the first heat regenerator 106 to increase the supercooling degree of the working medium (state point 4-23), and then enters the evaporation side of the evaporative condenser 107 to absorb heat (state point 8-9) after being throttled, depressurized and cooled by the first throttle valve 117 (state point 23-8). The working medium flowing out of the outlet of the first ejector 104 absorbs heat through the overheating side of the first heat regenerator 106 to become superheated steam (state points 5-24), and enters the air supplementing port of the compressor 101, so that air supplementing and enthalpy increasing are realized, and the energy saving performance and the stability of the system in operation under the low-temperature working condition are ensured.

In this embodiment, the structure of first sprayer 104 can be adjusted, adopt the current first sprayer that can adjust the structure can, first sprayer 104 structure can be adjusted and then realize the regulation of nozzle distance and throat area isoparametric to can find suitable tonifying qi point when the operating mode changes, make the system have certain variable operating condition operational capability.

The gas outlet of the first gas-liquid separator 103 is connected with the inlet of the cold side of the second heat regenerator 113 through a pipeline, the outlet of the cold side of the second heat regenerator 113 is connected with the inlet of the condensation side of the evaporative condenser 107 through a pipeline, the outlet of the condensation side of the evaporative condenser 107 is connected with the inlet of the second gas-liquid separator 109 through a pipeline, a second pressure-reducing and temperature-reducing element is installed on the pipeline between the outlet of the condensation side of the evaporative condenser 107 and the inlet of the second gas-liquid separator 109, and the second pressure-reducing and temperature-reducing element adopts a second throttle valve 108.

The gas flowing out of the first gas-liquid separator 103 is cooled by the sub-cooling side of the second heat regenerator 113, and then further enters the condensing side of the evaporator condenser 107 for condensation, and the heat is released to become saturated liquid under corresponding pressure.

The second gas-liquid separator 109 has an inlet, a liquid outlet and a gas outlet, the liquid outlet of the second gas-liquid separator 109 is connected with the inlet of the supercooling side of the third thermal regenerator 110, the outlet of the supercooling side of the third thermal regenerator 110 is connected with the inlet of the evaporator 112 through a pipeline, and a third pressure and temperature reducing element is installed on the pipeline between the outlet of the supercooling side of the third thermal regenerator 110 and the inlet of the evaporator 112, and the third pressure and temperature reducing element adopts a third throttle valve 111. The outlet of the evaporator 112 is connected to the inlet of the hot side of the third regenerator 110 through a pipeline, and the outlet of the hot side of the third regenerator 110 is connected to the inlet of the secondary flow of the second ejector 115 through a pipeline.

The third throttle valve 111 is capable of reducing the pressure and temperature of the liquid entering the evaporator 112 such that the temperature of the gas entering the hot side of the third regenerator 110 resulting from the evaporation of the evaporator 112 is lower than the temperature of the liquid inside the cold side of the third regenerator 110.

The outlet of the second ejector 115 is connected with the inlet of the overheating side of the second regenerator 113, the outlet of the overheating side of the second regenerator 113 is connected with the air suction port of the compressor 101, the gas in the overheating side of the second regenerator 113 exchanges heat with the gas in the overheating side of the second regenerator 113 discharged by the first gas-liquid separator 103, and enters the compressor after absorbing heat, so that the temperature gradient in the front and at the back of the compressor 101 can be effectively reduced, liquid impact is prevented from occurring during air supply, and the service life is prolonged.

The third throttle valve 111 causes the pressure and temperature of the liquid entering the evaporator 112 to decrease, and the temperature of the gas generated by the evaporation of the evaporator 112 is lower than the temperature of the liquid in the over-cooled side of the third regenerator 110.

The gas outlet of the second gas-liquid separator 109 is connected to the secondary flow inlet of the third ejector 114 via a pipe, and the outlet of the third ejector 114 is connected to the primary flow inlet of the second ejector 115.

The superheated steam (state point 3) rich in the working medium with low boiling point discharged from the gas outlet of the first gas-liquid separator 103 passes through the cold side of the second heat regenerator 113 to release heat (state point 3-10) and then enters the evaporative condenser 107 to release heat to become saturated liquid (state point 10-11) under corresponding pressure, and then passes through the second throttle valve 108 to throttle, reduce pressure and cool (state point 11-12) and enter the second gas-liquid separator 109. The throttled flash gas (state point 14) enters a second ejector 115 through a third ejector 114 to convert pressure energy into kinetic energy (14-14') to draw refrigerant vapor (19) from the evaporator 112. At this time, the third ejector 114 only functions as a gas flow channel, the throttled saturated liquid refrigerant (state point 13) firstly passes through the super-cold side (state points 13-16) of the third regenerator 110, then enters the evaporator 112 to absorb heat (state points 17-18) under the throttling, pressure-reducing and temperature-reducing effects of the third throttle 111 (state points 16-17), then passes through the super-hot side of the third regenerator 110 to continuously absorb heat (state points 18-19), and finally enters the second ejector 115 to be ejected. The working medium absorbs heat from the outlet of the second ejector 115 through the hot side of the second regenerator 113 (state points 21-22), enters the air suction port of the compressor 101, is compressed to intermediate pressure (state points 22-22 '), is mixed with the air supplement working medium entering the air supplement port and is continuously compressed (state points 1' -1), and then a cycle is completed.

In this embodiment, through setting up second sprayer 115, can retrieve the work of expanding, reduce the throttling loss, improve compressor 101 induction port pressure, reduce the specific volume of breathing in, increase the gas transmission volume, make compressor 101 still can stable work under the low temperature operating mode, improve the efficiency of system, and through setting up three regenerator, the utilization ratio of system to the energy has been improved, compressor 101 breathes in and can effectually reduce the temperature gradient around compressor 101 through 113 overheated second regenerators, take place the liquid attack when preventing the tonifying qi, increase of service life.

The above embodiment is mainly applied to the low-temperature region with the working condition between-40 ℃ and-70 ℃, when the working condition is below-70 ℃, although the second ejector can recover the expansion work, the pressure of the air suction port of the compressor is still very low, thereby leading to the increase of the suction specific volume and the reduction of the air delivery volume.

Therefore, as shown in fig. 3, the compression refrigeration cycle system of the present embodiment further includes a third gas-liquid separator 105, and the third gas-liquid separator 105 includes an inlet, a gas outlet, and a liquid outlet, and the second stop valve 116-3 is installed at the inlet, the third stop valve 116-1 is installed at the gas outlet, and the fourth stop valve 116-2 is installed at the liquid outlet.

The inlet of the third gas-liquid separator 105 is connected to the outlet of the first ejector 104.

The liquid outlet of the third gas-liquid separator 105 is connected to the inlet on the superheat side of the first recuperator 106 at a position between the first shut-off valve 116-4 and the inlet on the superheat side of the first recuperator 106.

The gas outlet of the third gas-liquid separator 105 is connected to the primary flow inlet of the third ejector 114.

When the device is applied to the working condition of-40 ℃ to 70 ℃, the second stop valve 116-3, the third stop valve 116-1 and the fourth stop valve 116-2 are closed, at the moment, the third gas-liquid separator 105 does not work, and the third ejector 114 only plays a role of a working medium circulation channel.

When the material is applied to the working condition below-70 ℃,

as shown in fig. 4, the two-phase fluid (state point 5) at the outlet of the first ejector 103 enters the third gas-liquid separator 105 to be separated into saturated refrigerant vapor (state point 7) and saturated refrigerant liquid (state point 6). The saturated refrigerant liquid (state point 6) absorbs heat in the superheat side of the first recuperator 106, becomes superheated vapor at that pressure (state points 6-24), and then enters the makeup port of the compressor 101. The saturated refrigerant vapor (state point 7) enters the third ejector to convert the pressure energy into kinetic energy (state point 7-7'), so that the saturated low-boiling-point working medium vapor (state point 14) from the second gas-liquid separator 109 is ejected. The flow from the outlet of the third ejector 114 (state point 20) enters the second ejector 115 to convert the pressure energy to kinetic energy (state points 20-20 ") to eject the superheated gas from the hot side of the third regenerator 110 (state point 19). Working fluid enters the suction port of compressor 101 from the outlet of second ejector 114 through the hot side of second regenerator 113 to absorb heat (state points 21-22). And the mixture is compressed to the intermediate pressure (state point 22-22 ') and mixed with the air supplement working medium entering from the air supplement port and compressed continuously (state point 1' -1), thereby completing a cycle, and the other processes are the same as the working principle under the working condition of-40 ℃ to-70 ℃, which is not described herein again.

Example 2

The embodiment provides a quasi-secondary compression type circulating system with an ejector for synergism, and the quasi-secondary compression type circulating system is a quasi-secondary compression heat pump circulating system with an ejector for synergism.

As shown in fig. 5-6, the system comprises a compressor 101, an outlet of the compressor 101 is connected to an inlet of a condenser 102 through a pipeline, an outlet of the condenser 102 is divided into two paths, one path is connected to a primary flow inlet of a fourth ejector 118 through a pipeline, and the other path is connected to an inlet of a fourth pressure and temperature reducing element through a pipeline, in this embodiment, the fourth pressure and temperature reducing element adopts a fourth throttle valve 119.

An outlet of the fourth ejector 118 is connected to a superheat-side inlet of the fifth regenerator 120, a superheat-side outlet of the fifth regenerator 120 is connected to an inlet of a fourth gas-liquid separator 121, a gas outlet of the fourth gas-liquid separator 121 is connected to a gas supply port of the compressor 101 through a pipeline, and a liquid outlet of the fourth gas-liquid separator 121 is connected to a primary flow inlet of the fifth ejector 122.

An outlet of the fourth throttle valve 119 is connected to an inlet of a fifth gas-liquid separator 123, a liquid outlet of the fifth gas-liquid separator 123 is connected to a secondary flow inlet of the fifth ejector 122 through a pipeline, and a gas outlet of the fifth gas-liquid separator 123 is connected to a secondary flow inlet of the fourth ejector 118 through a pipeline.

The outlet of the fifth ejector 122 is connected to the subcooling-side inlet of the fourth regenerator 124 through a pipe, the subcooling-side inlet of the fourth regenerator 124 is further connected to the subcooling-side outlet of the fifth regenerator 120, and the subcooling-side inlet of the fifth regenerator 120 is connected to the outlet of the condenser 102.

In this embodiment, the fifth pressure-reducing and temperature-reducing element adopts a fifth throttle valve 125, an outlet of the fifth throttle valve 125 is connected to an inlet of the evaporator 112, an outlet of the evaporator 112 is connected to an inlet of the fourth regenerator 124 on the superheat side, and an outlet of the fourth regenerator 124 on the superheat side is connected to an air suction port of the compressor 101.

In this embodiment, the sixth pressure and temperature reducing element adopts a sixth throttling valve 126, an outlet of the sixth throttling valve 126 is connected with an inlet of a sixth gas-liquid separator 127, a gas outlet of the sixth gas-liquid separator 127 is connected with a fifth gas-liquid separator 123 through a pipeline, and a liquid outlet of the sixth gas-liquid separator 127 is connected with an inlet of the evaporator 112.

In the first operation mode of the compression heat pump cycle system of the present embodiment, the sixth throttle valve 126 is closed, the fourth throttle valve 119 and the fifth throttle valve 125 are opened, and the fifth regenerator 120 only functions as a pipeline, and its operation principle is:

the superheated vapor flowing out of the outlet of the compressor 101 condenses into heat in the condenser 102 (state point 13-1) to be condensed into a supercooled liquid at the condensing pressure. One of the sub-cooled liquids passes through the fourth ejector 118 to convert the pressure energy into kinetic energy (state point 1-1'), thereby ejecting the saturated steam (state point 3) from the fifth gas-liquid separator 123. The other path is throttled and depressurized (state point 1-2) by a fourth throttle valve 119 and enters a fifth gas-liquid separator 123 to be separated into saturated steam (state point 3) and saturated liquid (state point 4). The refrigerant flowing out of the outlet of the fourth ejector 118 (state point 5) enters the fourth gas-liquid separator 121 to be separated into saturated vapor (state point 6) and saturated liquid (state point 7) at respective pressures. The saturated vapor (state point 6) of the fourth gas-liquid separator 121 enters the air supply port of the compressor 101, and the saturated liquid (state point 7) of the fourth gas-liquid separator 121 enters the fifth ejector 122 to convert the pressure energy into the kinetic energy (state point 7-7') to eject the saturated liquid (state point 4) from the fifth gas-liquid separator 123. The outlet of the fifth ejector 122 passes through the supercooling side of the fourth heat regenerator 124 to increase the supercooling degree (state point 8-9), the temperature of the liquid working medium is reduced, then the liquid working medium passes through the fifth throttle valve 125 to be throttled and reduced in pressure (state point 9-10) to enter the evaporator 112, the cold energy is absorbed in the evaporator 112 (state point 10-11), and then the superheat degree of the liquid working medium is increased through the superheating side of the fourth heat regenerator 124 (state point 11-12), and the temperature of the gas working medium is increased. Then enters the air inlet of the compressor 101, is compressed to an intermediate pressure (state point 12-12 ') and is mixed with the air supplementing working medium (state point 6) (state point 13'), and then is continuously compressed (state point 13), thereby completing a cycle.

As shown in fig. 7 to 8, in the second operation mode of the present embodiment, the sixth throttle valve 126 is opened, the fourth throttle valve 119 and the fifth throttle valve 125 are closed, and the fourth gas-liquid separator 121 and the fifth gas-liquid separator 123 function only as a pipeline, and the specific operation principle is as follows:

the superheated vapor flowing from the outlet of the compressor 101 condenses in the condenser 102 releasing heat (4-1) to condense into a subcooled liquid at the condensing pressure. One path of the supercooled liquid under the condensing pressure passes through the fourth ejector 118 to convert the pressure energy into kinetic energy (state point 1-1'), thereby ejecting saturated steam from the sixth gas-liquid separator 127 (state point 3). Working medium at the outlet (state point 5) of the fourth ejector 118 passes through the hot side (state point 5-6) of the fifth heat regenerator 120 to increase the superheat degree and enters the air supplementing port of the compressor 101. The other path of the supercooled liquid discharged from the condenser 102 passes through the supercooling side of the fifth regenerator 120 to increase the supercooling degree (state point 1-2), then passes through the supercooling side of the fourth regenerator 124 to continuously increase the supercooling degree (2-7), the temperature of the liquid is reduced, and then the supercooled liquid is throttled and decompressed (state point 7-8) by the sixth throttle valve 126 and enters the sixth gas-liquid separator 127 to be separated into saturated steam (state point 3) and saturated liquid (state point 9) under corresponding pressure. The saturated liquid (state point 9) enters the evaporator 112, absorbs cold (state point 9-10) in the evaporator 112, and then passes through the fourth regenerator 124 to increase its superheat (state point 10-11). Then enters the air inlet of the compressor 101, is compressed to an intermediate pressure (state point 11-11 ') and is mixed with the air supplementing working medium (state point 6) (state point 4'), and then is continuously compressed (state point 4), thereby completing a cycle.

In this embodiment, the structure of fourth sprayer 118 can be adjusted, adopt the current fourth sprayer that can adjust the structure can, the fourth sprayer structure can be adjusted and then realize the regulation of nozzle distance and throat area isoparametric to can find suitable tonifying qi point when the operating mode changes, make the system have certain variable operating condition operational capability, and through the setting of fourth sprayer and fifth sprayer, furthest retrieves the work of expanding, has reduced throttling loss.

Meanwhile, the liquid before entering the evaporator 112 is subcooled by the fourth heat regenerator 124, so that the dryness of the low-temperature refrigerant entering the evaporator 112 can be effectively reduced, the unit refrigerating capacity is improved, and the utilization rate of the area of the evaporator 112 is improved.

Although the embodiments of the present invention have been described with reference to the accompanying drawings, it is not intended to limit the scope of the present invention, and it should be understood by those skilled in the art that various modifications and variations can be made without inventive efforts by those skilled in the art based on the technical solution of the present invention.

Claims

1. The utility model provides a take accurate second grade compression circulation system of sprayer increase, for overlapping from restoring to the throne and compress refrigeration circulation system, including the compressor, the compressor is connected with the condenser, a serial communication port, the condenser is connected with first vapour and liquid separator, a liquid outlet of first vapour and liquid separator is connected with the primary current inlet of first sprayer, the export of first sprayer is connected with the tonifying qi mouth of compressor through the mistake hot side of first regenerator, another liquid outlet of first vapour and liquid separator loops through the cold side of crossing of first regenerator and the evaporation side access connection of first step-down cooling element with evaporative condenser, the export of evaporation side is connected with the secondary current inlet of first sprayer.

2. The quasi-two stage compression cycle system with ejector synergy of claim 1, wherein a shut-off valve is provided between the superheat side inlet of the first recuperator and the outlet of the first ejector.

3. The quasi-two-stage compression cycle system with ejector synergy of claim 1, wherein a condensation side inlet of the evaporative condenser is connected with a gas outlet of the first gas-liquid separator through a cold side of the second regenerator, a condensation side outlet of the evaporative condenser is connected with the second gas-liquid separator, a liquid outlet of the second gas-liquid separator is connected with the evaporator, and an outlet of the evaporator is connected with a compressor inlet;

4. The quasi-two-stage compression cycle system with the ejector synergy function according to claim 3, wherein a liquid outlet of the second gas-liquid separator is connected with an inlet of the evaporator sequentially through a cold side of a third heat regenerator and a third pressure and temperature reduction element, an outlet of the evaporator is connected with a secondary flow inlet of the second ejector through a hot side of the third heat regenerator, and an outlet of the second ejector is connected with an inlet of the compressor through the hot side of the second heat regenerator;

5. A quasi-two stage compressive cycle system with ejector synergy of claim 3, wherein the gas outlet of the second gas-liquid separator is connected to the primary flow inlet of the second ejector.

6. A quasi-two stage compression cycle system with ejector synergy as set forth in claim 3, wherein the gas outlet of the second gas-liquid separator is connected to the secondary flow inlet of a third ejector, the outlet of the third ejector is connected to the primary flow inlet of the second ejector, the primary flow inlet of the third ejector is connected to the gas outlet of the third gas-liquid separator, the inlet of the third gas-liquid separator is connected to the outlet of the first ejector, and the liquid outlet of the third gas-liquid separator is connected to the superheat side inlet of the first regenerator;

7. The utility model provides a take accurate second grade compression circulation system of sprayer increase, is compression heat pump circulation system, includes the compressor, the compressor is connected with the condenser, its characterized in that, the export of condenser respectively with the import of the primary stream of fourth sprayer and the access connection of fourth step-down cooling element, the export of fourth sprayer is passed through the gas make-up port of fourth vapour and liquid separator and compressor and is connected, the export of fourth step-down cooling element is connected with fifth vapour and liquid separator, the gas outlet of fifth vapour and liquid separator and the secondary stream access connection of fourth sprayer.

8. The quasi-two-stage compression cycle system with the ejector synergy function as claimed in claim 7, wherein a liquid outlet of the fifth gas-liquid separator is connected with a secondary flow inlet of the fifth ejector, a liquid outlet of the fourth gas-liquid separator is connected with a primary flow inlet of the fifth ejector, an outlet of the fifth ejector is connected with an inlet of the evaporator sequentially through a cold passing side of the fourth regenerator and the fifth pressure and temperature reduction element, and an outlet of the evaporator is connected with a suction port of the compressor through a hot passing side of the fourth regenerator.

9. The quasi-two-stage compression cycle system with ejector synergy of claim 7, further comprising a fifth regenerator, wherein the outlet of the condenser is connected to the subcooling side of the fourth regenerator through the subcooling side of the fifth regenerator, and wherein the outlet of the fourth ejector is connected to the fourth gas-liquid separator through the superheating side of the fifth regenerator.

10. The quasi-two-stage compression cycle system with ejector synergy of claim 9, wherein the subcooling side outlet of the fourth regenerator is connected to the sixth gas-liquid separator through a sixth pressure-reducing and temperature-reducing element, the gas outlet of the sixth gas-liquid separator is connected to the fifth gas-liquid separator, and the liquid outlet of the sixth gas-liquid separator is connected to the evaporator inlet.