CN113899095B - A Quasi-Secondary Compression Circulation System with Ejector Synergy - Google Patents

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

A Quasi-Secondary Compression Circulation System with Ejector Synergy

technical field

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

Background technique

The statements herein merely provide background related to the present invention and do not necessarily constitute prior art.

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

For the compression refrigeration cycle system, with the development of industry and the advancement of technology, biomedical, food industry, cold chain logistics and many other fields have put forward new requirements for low temperature refrigeration technology, especially the demand for temperature areas below -40 °C is increasing. strong. At present, the methods for realizing the above-mentioned low temperature area refrigeration mainly include: single working medium multi-stage compression refrigeration, mixed working medium two-stage cascade refrigeration, mixed working medium self-cascading refrigeration, and the like.

The self-cascading refrigeration system is a system that uses a non-azeotropic mixed working medium as a refrigerant and uses a compressor to achieve single/multi-stage fractional condensation, thereby obtaining a lower evaporation temperature. Because of its small size and wide cooling temperature range, it has broad application prospects in the field of general cooling and cryogenic cooling. However, the conventional self-cascading system has many problems, such as poor ability to change working conditions, serious throttling loss when the evaporation temperature is low, the suction specific volume decreases, the gas transmission volume decreases, and the compressor pressure ratio increases, etc., and it is difficult to meet the industrial requirements. Require.

In the prior art, the Chinese Patent Publication No. CN110762875A discloses a self-cascading heat pump unit with a large temperature difference and variable component concentration, which combines the air-supplying and enthalpy-increasing technology with the self-cascading refrigeration technology to reduce the pressure of the compressor. ratio and exhaust temperature. However, the inventor found that under low temperature conditions, the throttling loss of the refrigerant is serious, the energy utilization rate is low, the temperature difference between the front and rear of the compressor is too large, and the high-boiling point refrigerant is easy to liquefy after the supplemental gas is mixed, resulting in liquid shock of the compressor, and the system adaptability changes. Poor working ability.

For the compression heat pump circulation system, the vapor compression air source heat pump technology, as an energy-saving, environmentally friendly, safe and reliable heating technology, is increasingly used in the heating of commercial buildings and residences, such as heat pump air conditioners and thermal water heaters. With the improvement of people's living standards, heating in winter has increasingly become the focus of people's livelihood in autumn and winter. At present, when the traditional vapor-compressed air source heat pump works in a low outdoor environment, the suction specific volume of the compressor increases and the air delivery volume decreases. , and the compressor pressure ratio increases, the exhaust temperature is too high, and the compressor seriously deviates from the design working condition, which has a great impact on the energy saving and safety of the system.

In order to make the heat pump system operate efficiently, safely and stably in the low temperature outdoor environment, many improved schemes and solutions have been proposed. At present, the most widely used is the circulation system that uses supplementary gas to increase enthalpy, also known as the quasi-two-stage compression circulation system. The compressor of the air source heat pump using the supplementary air enthalpy technology sucks in a part of the intermediate pressure gas through the intermediate pressure suction hole, mixes it with the partially compressed refrigerant, and then compresses it, so that a single compressor can realize the process of two-stage compression. The air source heat pump with quasi-two-stage compression technology can adapt to lower outdoor ambient temperature than the ordinary air source heat pump. However, as the evaporation temperature decreases, the irreversible loss of throttling increases, and too much 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 injector efficiency enhancement, which increases the suction pressure of the compressor and reduces the power consumption of the compressor. During operation, it is difficult to find a suitable air supply point under variable operating conditions only by adjusting the throttle valve.

SUMMARY OF THE INVENTION

The purpose of the present invention is to overcome the deficiencies of the prior art and provide a quasi-two-stage compression type circulation system with injector efficiency enhancement, which can ensure the energy saving and stability of operation under low temperature conditions, and at the same time, the system has certain The ability to change working conditions can find a suitable gas supply point when the working conditions change.

In order to achieve the above object, the present invention adopts the following technical solutions

In a first aspect, embodiments of the present invention provide a quasi-two-stage compression cycle system with ejector efficiency enhancement, which is a self-cascading compression refrigeration cycle system, including a compressor, the compressor is connected to a condenser, and the condenser is connected to a self-cascading compression refrigeration cycle system. The first gas-liquid separator is connected, a liquid outlet of the first gas-liquid separator is connected with the primary flow inlet of the first ejector, and the outlet of the first ejector is connected to the air supply port of the compressor through the superheated side of the first regenerator connection, the other liquid outlet of the first gas-liquid separator is connected to the inlet of the evaporation side of the evaporative condenser through the subcooling side of the first regenerator and the first pressure-reducing and cooling element in turn, and the outlet of the evaporation side is connected to the first ejector the secondary flow inlet connection.

Optionally, a shut-off valve is provided between the superheated side inlet of the first regenerator and the outlet of the first injector.

Optionally, the condensation side inlet of the evaporative condenser is connected to the gas outlet of the first gas-liquid separator through the subcooled side of the second regenerator, and the condensation side outlet of the evaporative condenser is connected to the second gas-liquid separator. , the liquid outlet of the second gas-liquid separator is connected to the evaporator, and the outlet of the evaporator is connected to the compressor inlet.

Further, a second decompression and temperature reduction element is provided between the inlet of the second gas-liquid separator and the outlet of the condensation side of the evaporative condenser.

Optionally, the liquid outlet of the second gas-liquid separator is sequentially connected to the inlet of the evaporator through the subcooling side of the third regenerator and the third pressure-reducing and cooling element, and the outlet of the evaporator passes through the third regenerator. The superheated side of the second regenerator is connected to the secondary flow inlet of the second ejector, and the outlet of the second ejector is connected to the inlet of the compressor through the superheated side of the second regenerator.

Further, a throttle valve is used for the third pressure reduction and cooling element between the outlet of the subcooled side 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 inflow inlet of the second ejector.

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

Further, shut-off valves are installed at the inlet, gas outlet and liquid outlet of the third gas-liquid separator.

In a second aspect, embodiments of the present invention provide a quasi-two-stage compression type circulation system with ejector boosting efficiency, which is a compression heat pump circulation system, including a compressor, the compressor is connected to a condenser, and the outlet of the condenser is It is respectively connected with the primary flow inlet of the ejector I and the inlet of the depressurization and cooling element I, the outlet of the ejector I is connected with the air supply port of the compressor through the gas-liquid separator I, and the outlet of the depressurization and cooling element I is connected with the gas-liquid separator I. The separator II is connected, and the gas outlet of the gas-liquid separator II is connected with the secondary flow inlet of the ejector I.

Optionally, the liquid outlet of the gas-liquid separator II is connected to the secondary flow inlet of the ejector II, the liquid outlet of the gas-liquid separator I is connected to the primary flow inlet of the ejector II, and the outlet of the ejector II passes through in turn. The subcooling side of the regenerator I and the depressurizing and cooling element II are connected to the inlet of the evaporator, and the outlet of the evaporator is connected to the suction port of the compressor through the superheating side of the regenerator I.

Optionally, it also includes a regenerator II, the outlet of the condenser is connected to the subcooled side of the regenerator I through the subcooled side of the regenerator II, and the outlet of the ejector I is connected to the gas through the superheated side of the regenerator II. Liquid separator I is connected.

Optionally, the outlet of the subcooled side of the regenerator I is connected to the gas-liquid separator III through the pressure reduction and cooling element III, the gas outlet of the gas-liquid separator III is connected to the gas-liquid separator II, and the gas-liquid separator III is connected. The liquid outlet is connected to the evaporator inlet.

Beneficial effects of the present invention:

1. The compression refrigeration cycle system of the present invention has a first ejector, and the first ejector cooperates with the first regenerator and the evaporative condenser, which can realize the air supply to the compressor air supply port, and can ensure that the system works at low temperature. At the same time, setting the first injector can find a suitable air supply point when the working conditions change through the structural adjustment of the first injector, so that the system has a certain operating ability under variable working conditions.

2. In the compression refrigeration cycle system of the present invention, by setting the first regenerator, the second regenerator and the third regenerator, the utilization rate of the energy of the system is improved, and the compressor suction is superheated through the second regenerator. It can effectively reduce the temperature gradient before and after the compressor, prevent liquid hammer from occurring during air supply, and prolong the service life.

3. In the compression refrigeration cycle system of the present invention, by setting the second ejector, the expansion work can be recovered, the throttling loss can be reduced, the pressure at the suction port of the compressor can be increased, the suction specific volume can be reduced, the gas delivery volume can be increased, and the compressor It can still work stably under low temperature conditions and improve the energy efficiency of the system.

4. The compression refrigeration cycle system of the present invention is provided with a third ejector and a third gas-liquid separator. When the evaporation temperature is too low, although the second ejector can recover the expansion work, the pressure at the suction port of the compressor remains the same. It is very low, resulting in an increase in the suction specific volume and a decrease in the gas delivery volume. The third ejector is used to supplement the high-pressure and high-boiling refrigerant vapor into the suction port of the compressor, which can increase the pressure of the suction port and reduce the The pressure ratio of the compressor enables the compressor to operate stably at a lower temperature and improves the energy efficiency of the system.

5. The compression heat pump circulation system of the present invention has an ejector I, a gas-liquid separator I and a gas-liquid separator II, which can supplement the air supply port of the compressor, realize the gas supplementation and increase the enthalpy, and can ensure that the system operates at low temperature. At the same time, by adjusting the structure of the injector I, it is possible to find a suitable gas supply point when the working conditions change, so that the system has a certain ability to operate under variable working conditions.

6. The compression heat pump circulation system of the present invention has ejector I and ejector II, which maximizes recovery of expansion work and reduces throttling loss.

7. The compression heat pump circulation system of the present invention can effectively reduce the dryness of the low-temperature refrigerant entering the evaporator through the setting of the regenerator I and the regenerator II, increase the unit cooling capacity, and improve the utilization rate of the area of the evaporator. .

Description of drawings

The accompanying drawings that constitute a part of the present application are used to provide further understanding of the present application, and the schematic embodiments and descriptions of the present application are used to explain the present application and do not constitute a limitation to the present application.

FIG. 1 is a schematic diagram of the operation principle of Example 1 of the present invention under -40°C to -70°C working conditions;

Fig. 2 is a pressure-enthalpy diagram of Example 1 of the present invention operating under -40°C to -70°C;

FIG. 3 is a schematic diagram of the operation of Example 1 of the present invention under -70° C.;

Figure 4 is a pressure-enthalpy diagram of Example 1 of the present invention operating under -70°C;

FIG. 5 is a schematic diagram of the principle of Embodiment 2 of the present invention operating in the first working mode;

6 is a pressure-enthalpy diagram of Embodiment 2 of the present invention operating in a first working mode;

FIG. 7 is a schematic diagram of the principle of Embodiment 2 of the present invention operating in the second working mode;

FIG. 8 is a pressure-enthalpy diagram of Embodiment 2 of the present invention running in the second working mode;

Among them, 101. compressor, 102. condenser, 103. first gas-liquid separator, 104. first ejector, 105. third gas-liquid separator, 106. first regenerator, 107. evaporative condenser , 108. The second throttle valve, 109. The second gas-liquid separator, 110. The third regenerator, 111. The third throttle valve, 112. The evaporator, 113. The second regenerator, 114. The first Three injectors, 115. The second injector, 116-1. The third stop valve, 116-2. The fourth stop valve, 116-3. The second stop valve, 116-4. The first stop valve, 117. The first stop valve Throttle valve, 118. Ejector I, 119. Fourth throttle valve, 120. Regenerator II, 121. Gas-liquid separator I, 122. Ejector II, 123. Gas-liquid separator II, 124. Regenerator I, 125. Fifth throttle valve, 126. Sixth throttle valve, 127. Gas-liquid separator III.

Detailed ways

Example 1

This embodiment provides a quasi-two-stage compression cycle system with ejector efficiency enhancement, which is a self-cascading quasi-two-stage compression refrigeration cycle system with ejector efficiency enhancement, as shown in FIG. 1 , including a compressor 101, Condenser 102, evaporator 112, evaporative condenser 107, three gas-liquid separators, three ejectors and three regenerators.

In this embodiment, the regenerator can use the existing equipment, which has an overheating side and a subcooling side. The working medium to be heated flows in from the inlet of the overheating side and flows out from the outlet of the overheating side, and the working medium to be cooled flows from the inlet of the subcooling side. flows in and flows out from the outlet on the subcooled side.

The superheated side in the regenerator means that the working medium flows into the regenerator from the inlet of the superheated side, and flows out of the regenerator at the outlet of the superheated side. Heat exchange occurs inside the regenerator, and the temperature of the working medium increases.

The subcooling side in the regenerator means that the working fluid flows into the subcooling side from the inlet of the subcooling side, and then flows out from the outlet of the subcooling side. The working fluid undergoes heat exchange in the regenerator and the temperature decreases.

The evaporative condenser 112 can use existing equipment and has an evaporating side and a condensing side. The evaporating side refers to the side where the inflowing working medium is heated from a liquid or two-phase working medium to a gaseous state, and the condensing side refers to the inflowing working medium. The side where the exotherm changes from gaseous to liquid.

The gas-liquid separator can use existing equipment, which can separate the inflowing working medium from gas and liquid.

The ejector may be an existing ejector, which can convert the pressure of the inflowing working medium into the flow kinetic energy of the working medium.

The air outlet of the compressor 101 is connected to the inlet of the condenser 102 through a pipeline, and the outlet of the condenser 102 is connected to the inlet of the 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, and the outlet of the first ejector 104 is connected to the superheated side inlet of the first regenerator 106 through a pipeline Connection, the outlet of the superheated side of the first regenerator 106 is connected to the air supply port of the compressor 101 through the supply air pipeline.

Wherein, a first shut-off valve 116-4 is installed on the pipe between the outlet pipe of the first injector 104 and the inlet of the superheated side of the first regenerator 106, and the first shut-off valve 116-4 is used to control the flow of the pipe. on and off.

The other liquid outlet of the first gas-liquid separator 103 is connected to the inlet of the subcooled side of the first regenerator 106, and the outlet of the subcooled side of the first regenerator 106 and the inlet of the evaporation side of the evaporative condenser 107 pass through. The pipeline is connected, and the pipeline between the outlet of the subcooling side of the first regenerator 106 and the inlet of the evaporative side of the evaporative condenser 107 is installed with a first depressurization and cooling element, and the first depressurization and cooling element adopts the first throttle valve 117 , which can reduce the pressure and temperature of the fluid flowing inside the pipeline. Therefore, the temperature of the gas generated after the liquid is evaporated by the evaporative condenser 107 is lower than the temperature of the liquid in the subcooled side of the first regenerator 106 .

The evaporative side outlet of the evaporative condenser 107 is connected to the secondary flow inlet of the first ejector 104 through a pipeline.

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

The refrigerant liquid rich in high boiling point is divided into two branches, one way 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 way passes through the first regenerator 106 to increase the degree of subcooling of the working medium (state point 4-23), and then passes through the first throttle valve 117 to throttle and reduce the temperature (state point 23-8) and enter the evaporative condenser The evaporation side of 107 absorbs heat (state points 8-9). The working medium flowing out from the outlet of the first ejector 104 passes through the superheated side of the first regenerator 106 to absorb heat and becomes superheated steam (state points 5-24), and enters the air supply port of the compressor 101, realizing the air supply and enthalpy increase, ensuring the system Energy saving and stability in low temperature operation.

In this embodiment, the structure of the first injector 104 can be adjusted, and an existing first injector with an adjustable structure can be used, and the structure of the first injector 104 can be adjusted to achieve nozzle distance and throat area, etc. By adjusting the parameters, it is possible to find a suitable gas supply point when the working conditions change, so that the system has a certain ability to operate under variable working conditions.

The gas outlet of the first gas-liquid separator 103 is connected to the inlet of the subcooled side of the second regenerator 113 through a pipeline, and the outlet of the subcooled side of the second regenerator 113 is connected to the evaporative condensation through a pipeline. The inlet of the condensation side of the evaporative condenser 107 is connected to the inlet of the condensation side of the evaporative condenser 107, the outlet of the condensation side of the evaporative condenser 107 is connected to the inlet of the second gas-liquid separator 109 through a pipeline, and the outlet of the condensation side of the evaporative condenser 107 is connected to the second gas-liquid separator 109. A second pressure-reducing and cooling element is installed on the pipeline between the inlets of the 2000 , and the second pressure-reducing and cooling element adopts a second throttle valve 108 .

The gas flowing out of the first gas-liquid separator 103 passes through the subcooled side of the second regenerator 113 for cooling, and further enters the condensation side of the evaporator condenser 107 for condensation, and the heat is released into a saturated liquid under the 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 to the inlet of the subcooled side of the third regenerator 110, and the third regenerator The outlet of the subcooling side of the regenerator 110 is connected to the inlet of the evaporator 112 through a pipeline, and a third cooling tube is installed on the pipeline between the outlet of the subcooling side of the third regenerator 110 and the inlet of the evaporator 112. The pressure and temperature reduction element, the third pressure reduction and cooling element adopts the third throttle valve 111 . The outlet of the evaporator 112 is connected to the inlet of the superheated side of the third regenerator 110 through a pipeline, and the outlet of the superheated side of the third regenerator 110 is connected to the secondary flow inlet of the second ejector 115 through a pipeline .

The third throttle valve 111 can reduce the pressure and temperature of the liquid entering the evaporator 112 , so that the temperature of the gas entering the superheated side of the third regenerator 110 obtained by the evaporation of the evaporator 112 is lower than that of the liquid inside the subcooling side of the third regenerator 110 temperature.

The outlet of the second ejector 115 is connected to the inlet of the superheated side of the second regenerator 113 , the outlet of the superheated side of the second regenerator 113 is connected to the suction port of the compressor 101 , and the outlet of the superheated side of the second regenerator 113 is connected to the suction port of the compressor 101 . The gas exchanges heat with the gas discharged from the first gas-liquid separator 103 on the subcooled side of the second regenerator 113, and enters the compressor after absorbing heat, which can effectively reduce the temperature gradient before and after the compressor 101, and prevent compensation. Hydraulic shock occurs when the gas is inflated, prolonging the service life.

The third throttle valve 111 reduces the pressure and temperature of the liquid entering the evaporator 112 , so that the temperature of the gas produced by the evaporation of the evaporator 112 is lower than the temperature of the liquid in the subcooling 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 injector 114 through a pipeline, and the outlet of the third injector 114 is connected to the primary flow inlet of the second injector 115 .

The superheated steam (state point 3) rich in low-boiling point working fluid discharged from the gas outlet of the first gas-liquid separator 103 passes through the subcooled side of the second regenerator 113 to release heat (state points 3-10) and then enters the evaporative condenser 107 The exothermic heat becomes saturated liquid under the corresponding pressure (state points 10-11), and then enters the second gas-liquid separator 109 through the second throttle valve 108 to be throttled and reduced in temperature (state points 11-12). The throttled flash gas (state point 14) enters through the third ejector 114 into the second ejector 115 to convert the pressure energy into kinetic energy (14-14') to eject the refrigerant vapor from the evaporator 112 ( 19). At this time, the third ejector 114 only functions as a gas circulation channel, and the throttled saturated liquid refrigerant (state point 13) first passes through the subcooled side of the third regenerator 110 (state points 13-16), Then, under the action of throttling and depressurization of the third throttle valve 111 (state points 16-17), it enters the evaporator 112 to absorb heat (state points 17-18), and then continues to absorb heat through the superheated side of the third regenerator 110 Heat (state points 18-19), finally enters the second injector 115 to be ejected. The working fluid enters the suction port of the compressor 101 from the outlet of the second ejector 115 through the superheated side of the second regenerator 113 (state points 21-22), and is compressed to the intermediate pressure (state points 22-22') and The supplemental gas working medium entering the supplementary gas port is mixed and continues to be compressed (state point 1'-1), thereby completing a cycle.

In this embodiment, by arranging the second ejector 115, the expansion work can be recovered, the throttling loss can be reduced, the suction port pressure of the compressor 101 can be increased, the suction specific volume can be reduced, the gas delivery volume can be increased, and the compressor 101 can be kept at a low temperature. It can still work stably under working conditions, improve the energy efficiency of the system, and by setting three regenerators, the energy utilization rate of the system is improved, and the compressor 101 is superheated through the second regenerator 113, which can effectively reduce compression. The temperature gradient before and after the machine 101 prevents liquid slugging during air supply and prolongs the service life.

The above-mentioned embodiment is mainly applied to the low temperature region where the working condition is between -40°C and -70°C. When the working condition is below -70°C, although the second ejector can recover the expansion work, the pressure at the suction port of the compressor will not increase. is still very low, resulting in an increase in the suction specific volume and a decrease in the air delivery volume.

Therefore, as shown in FIG. 3 , the compression refrigeration cycle system of this 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 is installed at the inlet There is a second stop valve 116-3, a third stop valve 116-1 is installed at the gas outlet, and a 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 superheated side inlet of the first regenerator 106 , and the connection position is set between the first shut-off valve 116 - 4 and the superheated side inlet of the first regenerator 106 . Location.

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

When applied to the working conditions of -40°C-70°C, the second shut-off valve 116-3, the third shut-off valve 116-1 and the fourth shut-off valve 116-2 are closed, and the third gas-liquid separator 105 cannot be used at this time. Function, the third injector 114 only functions as a working medium flow channel.

When applied to conditions below -70°C,

As shown in FIG. 4 , the two-phase fluid (state point 5) exiting the first ejector 103 enters the third gas-liquid separator 105 and is separated into saturated refrigerant vapor (state point 7) and saturated refrigerant liquid (state point 7) 6). Saturated refrigerant liquid (state point 6) absorbs heat in the superheated side of the first regenerator 106, becomes superheated vapor at that pressure (state points 6-24), and then enters the compressor 101 supplemental port. The saturated refrigerant vapor (state point 7) enters the third ejector to convert the pressure energy into kinetic energy (state point 7-7'), thereby ejecting the saturated low-boiling point working medium vapor from the second gas-liquid separator 109 (state point 7-7') point 14). The third injector 114 exits fluid (state point 20) into the second injector 115 to convert pressure energy into kinetic energy (state point 20-20"), thereby ejecting superheated gas from the superheated side of the third regenerator 110 ( State point 19). The working fluid enters the suction port of the compressor 101 from the outlet of the second ejector 114 through the superheated side of the second regenerator 113 to absorb heat (state points 21-22) and is compressed to an intermediate pressure (state point 22). -22') is mixed with the supplemental gas working fluid entering the supplementary gas port and continues to compress (state point 1'-1), and then completes a cycle. The other processes are the same as the working principle of -40℃～-70℃ , which will not be repeated here.

Example 2

This embodiment provides a quasi-two-stage compression type circulation system with ejector efficiency enhancement, which is a pseudo-two-stage compression heat pump cycle system with ejector efficiency enhancement.

As shown in Figures 5-6, it includes a compressor 101, the outlet of the compressor 101 is connected to the inlet of the condenser 102 through a pipeline, and the outlet of the condenser 102 is divided into two paths, one of which is connected to the ejector through a pipeline The primary flow inlet of I118 is connected, and the other is connected to the inlet of the depressurization and cooling element I through a pipeline. In this embodiment, the depressurization and cooling element I adopts a fourth throttle valve 119 .

The outlet of the ejector I118 is connected to the inlet of the superheated side of the regenerator II120, the outlet of the superheated side of the regenerator II120 is connected to the inlet of the gas-liquid separator I121, and the gas outlet of the gas-liquid separator I121 is connected to the compressor through a pipeline. The air supply port of 101 is connected, and the liquid outlet of the gas-liquid separator I121 is connected to the primary flow inlet of the ejector II122.

The outlet of the fourth throttle valve 119 is connected to the inlet of the gas-liquid separator II123, the liquid outlet of the gas-liquid separator II123 is connected to the secondary flow inlet of the ejector II122 through a pipeline, and the gas outlet of the gas-liquid separator II123 It is connected to the secondary flow inlet of the injector I118 through a pipeline.

The outlet of the ejector II122 is connected to the inlet of the subcooled side of the regenerator I124 through a pipeline, and the inlet of the subcooled side of the regenerator I124 is also connected to the outlet of the subcooled side of the regenerator II120, and the regenerator II120 The inlet of the subcooled side of 1 is connected to the outlet of the condenser 102 .

The outlet of the supercooled side of the regenerator I 124 is connected to the inlet of the depressurization and cooling element II. In this embodiment, the depressurization and cooling element II adopts the fifth throttle valve 125, and the outlet of the fifth throttle valve 125 is connected to the The inlet of the evaporator 112 is connected, the outlet of the evaporator 112 is connected to the inlet of the superheated side of the regenerator I124, and the outlet of the superheated side of the regenerator I124 is connected to the suction port of the compressor 101.

The outlet of the supercooled side of the regenerator I 124 is also connected to the inlet of the depressurizing and cooling element III. In this embodiment, the sixth depressurizing and cooling element III adopts a sixth throttle valve The outlet is connected to the inlet of the gas-liquid separator III127, the gas outlet of the gas-liquid separator III127 is connected to the gas-liquid separator II123 through a pipeline, and the liquid outlet of the gas-liquid separator III127 is connected to the inlet of the evaporator 112.

In the first working mode of the compression heat pump circulation system of this embodiment, the sixth throttle valve 126 is closed, the fourth throttle valve 119 and the fifth throttle valve 125 are opened, and the regenerator II 120 only plays the role of a pipeline. The working principle is:

The superheated steam flowing out from the outlet of the compressor 101 condenses and releases heat in the condenser 102 (state point 13-1) to condense into a subcooled liquid at a condensing pressure. One of the subcooled liquids passes through the ejector I118 to convert the pressure energy into kinetic energy (state point 1-1'), thereby ejecting saturated steam from the gas-liquid separator II123 (state point 3). The other path is throttled and depressurized (state point 1-2) through the fourth throttle valve 119 and enters the gas-liquid separator II 123 to be separated into saturated steam (state point 3) and saturated liquid (state point 4). The refrigerant flowing out from the outlet of the ejector I118 (state point 5) enters the gas-liquid separator I121 and is separated into saturated vapor (state point 6) and saturated liquid (state point 7) under corresponding pressures. The saturated steam (state point 6) of the gas-liquid separator I121 enters the air supply port of the compressor 101, and the saturated liquid (state point 7) of the gas-liquid separator I121 enters and passes through the ejector II122 to convert the pressure energy into kinetic energy (state points 7-7 ') to eject the saturated liquid from the gas-liquid separator II 123 (state point 4). The outlet of ejector II 122 passes through the subcooled side of regenerator I 124 to increase the degree of subcooling (state points 8-9), the temperature of the liquid working medium decreases, and then throttles and reduces the pressure through the fifth throttle valve 125 (state points 9-10) Enter the evaporator 112, absorb the cold energy in the evaporator 112 (state point 10-11), and then increase its superheat degree through the superheated side of the regenerator I124 (state point 11-12), and the temperature of the gas working medium increases. Then enter the suction port of the compressor 101, and compress to the intermediate pressure (state point 12-12') and mix with the supplementary air working medium (state point 6) (state point 13'), and then continue to compress (state point 13), And then complete a cycle.

As shown in FIGS. 7-8 , in the second working mode of this embodiment, the sixth throttle valve 126 is opened, the fourth throttle valve 119 and the fifth throttle valve 125 are closed, and the gas-liquid separator I 121 is separated from the gas and liquid. The device II123 only plays the role of pipeline, and its specific working principle is as follows:

The superheated steam flowing out from the outlet of the compressor 101 is condensed in the condenser 102 to release heat (4-1) so as to be condensed into a supercooled liquid under the condensing pressure. The subcooled liquid under the condensing pressure passes through the ejector I118 all the way to convert the pressure energy into kinetic energy (state point 1-1'), thereby ejecting saturated steam from the gas-liquid separator III127 (state point 3). The working fluid at the outlet of ejector I118 (state point 5) passes through the superheated side of regenerator II 120 (state point 5-6) to increase the superheat degree and enters the air supply port of compressor 101. The subcooled liquid discharged from the condenser 102 passes through the subcooled side of the regenerator II 120 to increase its subcooling degree (state point 1-2), and then continues to increase its subcooling degree through the subcooled side of the regenerator I124 ( 2-7), the temperature of the liquid is reduced, and then it is throttled and depressurized through the sixth throttle valve 126 (state point 7-8) and enters the gas-liquid separator III 127 to be separated into saturated steam (state point 3) and saturated liquid under the corresponding pressure. (status point 9). Saturated liquid (state point 9) enters evaporator 112, absorbs cold energy in evaporator 112 (state point 9-10), and then increases its superheat degree through the superheated side of regenerator I 124 (state point 10-11). Then enter the suction port of the compressor 101, and compress to the intermediate pressure (state point 11-11') and mix with the supplementary gas working medium (state point 6) (state point 4'), and then continue to compress (state point 4), And then complete a cycle.

In this embodiment, the structure of the injector I 118 can be adjusted, and the existing injector I with adjustable structure can be used, and the structure of the injector I can be adjusted to realize the adjustment of parameters such as nozzle distance and throat area, thereby When the working conditions change, a suitable gas supply point can be found, so that the system has a certain operating ability under variable working conditions, and through the setting of ejector I and ejector II, the expansion work can be recovered to the maximum extent, and the throttling loss is reduced.

At the same time, the liquid before entering the evaporator 112 is subcooled by the regenerator I124, which can effectively reduce the dryness of the low-temperature refrigerant entering the evaporator 112, increase the unit cooling capacity, and improve the utilization rate of the evaporator 112 area.

Although the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, they do not limit the scope of protection of the present invention. Those skilled in the art should understand that on the basis of the technical solutions of the present invention, those skilled in the art do not need to pay creative work. Various modifications or deformations that can be made are still within the protection scope of the present invention.

Claims (9)

1. a kind of quasi-two-stage compression type circulation system with ejector synergy, is self-cascading compression refrigeration cycle system, comprises compressor, and compressor is connected with condenser, it is characterized in that, condenser and first gas-liquid separation A liquid outlet of the first gas-liquid separator is connected to the primary flow inlet of the first ejector, and the outlet of the first ejector is connected to the air supply port of the compressor through the superheated side of the first regenerator. The other liquid outlet of the liquid separator is sequentially connected to the evaporative side inlet of the evaporative condenser through the subcooling side of the first regenerator and the first decompression and cooling element, and the outlet of the evaporative side is connected to the secondary flow inlet of the first ejector connect. 2 . The quasi-two-stage compression type circulation system with injector boosting efficiency according to claim 1 , wherein a superheated side inlet of the first regenerator and the outlet of the first injector are provided. 3 . There is a shut-off valve. 3 . The quasi-two-stage compression type circulation system with ejector boosting efficiency according to claim 1 , wherein the inlet of the condensation side of the evaporative condenser passes through the subcooling side of the second regenerator and the second regenerator. 4 . The gas outlet of a gas-liquid separator is connected, the condensation side outlet of the evaporative condenser is connected with the second gas-liquid separator, the liquid outlet of the second gas-liquid separator is connected with the evaporator, and the outlet of the evaporator is connected with the compressor inlet; Further, a second decompression and temperature reduction element is provided between the inlet of the second gas-liquid separator and the outlet of the condensation side of the evaporative condenser. 4 . The quasi-two-stage compression type circulation system with injector boosting efficiency according to claim 3 , wherein the liquid outlet of the second gas-liquid separator passes through the subcooling of the third regenerator in sequence. 5 . The side and the third depressurizing and cooling element are connected to the inlet of the evaporator, the outlet of the evaporator is connected to the secondary flow inlet of the second ejector through the superheated side of the third regenerator, and the outlet of the second ejector is connected to the secondary flow inlet of the second ejector through the second regenerator. The superheating side of the heater is connected to the inlet of the compressor; Further, a throttle valve is used for the third pressure reduction and cooling element between the outlet of the subcooled side of the third regenerator and the inlet of the evaporator. 5 . The quasi-two-stage compression type circulation system with injector boosting efficiency according to claim 3 , wherein the gas outlet of the second gas-liquid separator is connected to the primary inflow port of the second injector. 6 . . 6. The quasi-two-stage compression type circulation system with injector boosting efficiency according to claim 3, wherein the gas outlet of the second gas-liquid separator and the secondary flow inlet of the third injector connection, the outlet of the third ejector is connected with the primary flow inlet of the second ejector, the primary flow inlet of the third ejector is connected with the gas outlet of the third gas-liquid separator, and the inlet of the third gas-liquid separator is connected with the first The outlet of the ejector is connected, and the liquid outlet of the third gas-liquid separator is connected with the inlet of the superheated side of the first regenerator; Further, shut-off valves are installed at the inlet, gas outlet and liquid outlet of the third gas-liquid separator. 7. A quasi-two-stage compression type circulation system with ejector efficiency enhancement, which is a compression heat pump circulation system, comprising a compressor, and the compressor is connected with a condenser, and it is characterized in that the outlet of the condenser is respectively connected with the ejector I The inlet of the primary stream of the first flow is connected with the inlet of the depressurization and cooling element I, the outlet of the ejector I is connected with the air supply port of the compressor through the gas-liquid separator I, and the outlet of the depressurization and cooling element I is connected with the gas-liquid separator II, The gas outlet of the gas-liquid separator II is connected with the secondary flow inlet of the ejector I; The liquid outlet of the gas-liquid separator II is connected with the secondary flow inlet of the ejector II, the liquid outlet of the gas-liquid separator I is connected with the primary flow inlet of the ejector II, and the outlet of the ejector II passes through the regenerator I in turn. The supercooling side of the regenerator and the depressurizing and cooling element II are connected to the inlet of the evaporator, and the outlet of the evaporator is connected to the suction port of the compressor through the superheating side of the regenerator I. 8. A quasi-two-stage compression type circulation system with ejector boosting efficiency as claimed in claim 7, characterized in that it further comprises a regenerator II, and the outlet of the condenser passes through the subcooled side of the regenerator II and is connected with the regenerator II. The subcooling side of the regenerator I is connected, and the outlet of the ejector I is connected to the gas-liquid separator I through the superheating side of the regenerator II. 9 . The quasi-two-stage compression type circulation system with injector boosting efficiency according to claim 8 , wherein the outlet of the subcooled side of the regenerator I is separated from the gas and liquid through the depressurization and cooling element III. 10 . The gas outlet of the gas-liquid separator III is connected with the gas-liquid separator II, and the liquid outlet of the gas-liquid separator III is connected with the inlet of the evaporator.

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