阅读说明：本技术 一种复叠制冷系统多功能集成型冷凝蒸发器 (Multi-functional integrated type condensation evaporator of cascade refrigerating system ) 是由 韩献军 宋立斌 于 2020-05-30 设计创作，主要内容包括：本发明公开了一种复叠制冷系统多功能集成型冷凝蒸发器,包括壳体,所述壳体内由上至下设置有上管板和整流层,将壳体内腔分为由上至下的回气腔、上换热腔和下换热腔；所述冷凝蒸发器还包括与下换热腔相连通的进气管以及与上换热腔相连通的出液管；所述冷凝蒸发器还包括蒸发侧管路,所述蒸发侧管路包括设置在上换热腔中的换热管组件,所述换热管组件的换热管上端与所述回气腔相通；所述蒸发侧管路还包括用于为回气腔中分离出的液体进行加热的第一换热装置和用于为下换热腔中冷凝出的液体进行过冷的第二换热装置。本发明具有换热性能好、充值量低、体积小等优点。(The invention discloses a multifunctional integrated condensing evaporator of a cascade refrigeration system, which comprises a shell, wherein an upper tube plate and a rectifying layer are arranged in the shell from top to bottom, and an inner cavity of the shell is divided into an air return cavity, an upper heat exchange cavity and a lower heat exchange cavity from top to bottom; the condensation evaporator also comprises an air inlet pipe communicated with the lower heat exchange cavity and a liquid outlet pipe communicated with the upper heat exchange cavity; the condensation evaporator also comprises an evaporation side pipeline, the evaporation side pipeline comprises a heat exchange pipe assembly arranged in the upper heat exchange cavity, and the upper end of a heat exchange pipe of the heat exchange pipe assembly is communicated with the air return cavity; the evaporation side pipeline also comprises a first heat exchange device used for heating the separated liquid in the air return cavity and a second heat exchange device used for supercooling the condensed liquid in the lower heat exchange cavity. The invention has the advantages of good heat exchange performance, low recharging amount, small volume and the like.)

1. The utility model provides a multi-functional integrated type condensation evaporator of cascade refrigerating system which characterized in that: the heat exchanger comprises a shell (1), wherein an upper tube plate (8) and a rectifying layer (5) are arranged in the shell (1) from top to bottom, and an inner cavity of the shell (1) is divided into an air return cavity, an upper heat exchange cavity and a lower heat exchange cavity from top to bottom;

the condensation evaporator also comprises an air inlet pipe (7) communicated with the lower heat exchange cavity and a liquid outlet pipe (19) communicated with the upper heat exchange cavity;

the condensation evaporator also comprises an evaporation side pipeline, the evaporation side pipeline comprises a heat exchange pipe assembly (2) arranged in the upper heat exchange cavity, and the upper end of a heat exchange pipe of the heat exchange pipe assembly (2) is communicated with the air return cavity;

the evaporation side pipeline also comprises a first heat exchange device used for heating the separated liquid in the air return cavity and a second heat exchange device used for supercooling the condensed liquid in the lower heat exchange cavity.

2. The multi-functional integrated type condensing evaporator of a cascade refrigeration system as set forth in claim 1, wherein: the condensation evaporator also comprises a liquid inlet, a first spiral pipe group (13) serving as a first heat exchange device, a throttle valve (16), a second spiral pipe group (18) serving as a second heat exchange device, a heat return cavity (12), a gas outlet pipe (10) and an oil return capillary pipe (11);

the liquid inlet is communicated with the heat exchange tube assembly (2) through a first spiral tube group (13), a throttle valve (16) and a second spiral tube group (18) in sequence;

the air return cavity is communicated with the regenerative cavity (12) through a pipeline (9), the first spiral tube group (13) is arranged in the regenerative cavity (12), the inlet end of the air outlet pipe (10) is communicated with the regenerative cavity (12), one end of the oil return capillary tube (11) is communicated with the air outlet pipe (10), and the other end of the oil return capillary tube is communicated with the bottom of the regenerative cavity (12);

a guide plate (17) positioned below the heat exchange tube assembly (2) is further arranged in the upper heat exchange cavity, and the guide plate (17) and the inner wall of the shell (1) enclose a liquid outlet heat exchange cavity with an upper opening; the second spiral pipe group (18) is arranged in the liquid outlet heat exchange cavity, and the inlet of the liquid outlet pipe (19) is communicated with the liquid outlet heat exchange cavity.

3. The multi-functional integrated type condensing evaporator of a cascade refrigeration system as set forth in claim 2, wherein: the second spiral tube group (18) is connected with the heat exchange tube assembly (2) through a gas-liquid distributor (14), and outlets of the gas-liquid distributor (14) are respectively connected with heat exchange tubes in the heat exchange tube assembly (2) in a one-to-one correspondence mode through guide tubes (4).

4. The multi-functional integrated type condensing evaporator of a cascade refrigeration system as set forth in claim 3, wherein: an ultrasonic oscillator (15) is arranged in the gas-liquid distributor (14).

5. The multi-functional integrated type condensing evaporator of a cascade refrigeration system as set forth in claim 3, wherein: the heat exchange tube is vertically arranged, a spiral channel is arranged in the heat exchange tube, and vertical prismatic protrusions which are uniformly distributed on the circumference are arranged on the outer surface of the heat exchange tube.

6. The multi-functional integrated type condensing evaporator of a cascade refrigeration system as set forth in claim 1, wherein: a lower tube plate (3) is further arranged in the upper heat exchange cavity, and the bottom of the heat exchange tube assembly (2) is installed in the shell (1) through the lower tube plate (3); the lower tube plate (3) is provided with a through hole.

7. The multi-functional integrated type condensing evaporator of a cascade refrigeration system as set forth in claim 2, wherein: the throttle valve (16) collects the temperature and pressure signals of the gas in the gas outlet pipe (10) and adjusts the opening degree of the throttle valve.

8. The multi-functional integrated type condensing evaporator of a cascade refrigeration system as set forth in claim 2, wherein: the upper tube plate (8) is obliquely arranged, and an inlet of the pipeline (9) is communicated with the bottom of the regenerative cavity (12).

9. The multi-functional integrated type condensing evaporator of a cascade refrigeration system as set forth in any one of claims 1 to 8, wherein: the air inlet pipe (7) is communicated with a rotary air diffuser (6) arranged in the lower heat exchange cavity.

Technical Field

The invention relates to the technical field of refrigeration, in particular to an integrated condensing evaporator of a cascade refrigeration system.

Background

The cascade refrigeration system has wide application, and the condensing evaporator is a key heat exchange component. The condensing evaporator of the cascade refrigeration system mostly adopts a flooded type or a gravity liquid supply type, and has the advantages of obtaining better heat exchange performance and improving the overall operation efficiency of the system.

The above scheme has the following disadvantages: the condensation evaporator assembly has large volume and large working medium filling amount, and is not beneficial to the integrated design of a cascade system; the compressor exhausts gas and is directly condensed, the temperature difference between two sides of the heat exchanger is too large (the exhaust superheat degree of the low-temperature side is very high, the exhaust temperature is about 80 ℃, the medium temperature of the high-temperature side is-30 ℃, and the temperature difference between two sides reaches more than 100 ℃ at the inlet of the heat exchanger), temperature stress which cannot be eliminated exists, the heat exchanger is damaged due to the temperature stress, the service life of the heat exchanger is shortened, and the reliability of the whole cascade refrigeration system is influenced; the flooded type and gravity liquid supply type condensing evaporator needs to be subjected to liquid level control and oil return control, and the control of the direct expansion type condensing evaporator is simpler and more reliable; and fourthly, the condensate is not supercooled or has small supercooling degree, so that the condensate is inconvenient to transport remotely.

Disclosure of Invention

The invention provides a multifunctional integrated condensing evaporator of a cascade refrigeration system, which aims to: heat exchange is enhanced, and the volume of the condensation evaporator assembly is reduced; the temperature difference at two sides of the heat exchanger is reduced, the temperature difference stress damage is eliminated, and the reliability is improved; the liquid level and oil return control are simplified, and the supercooling degree of the condensate is improved.

The technical scheme of the invention is as follows:

a multi-functional integrated condensing evaporator of a cascade refrigeration system comprises a shell, wherein an upper tube plate and a rectifying layer are arranged in the shell from top to bottom, and an inner cavity of the shell is divided into an air return cavity, an upper heat exchange cavity and a lower heat exchange cavity from top to bottom;

the condensation evaporator also comprises an air inlet pipe communicated with the lower heat exchange cavity and a liquid outlet pipe communicated with the upper heat exchange cavity;

the condensation evaporator also comprises an evaporation side pipeline, the evaporation side pipeline comprises a heat exchange pipe assembly arranged in the upper heat exchange cavity, and the upper end of a heat exchange pipe of the heat exchange pipe assembly is communicated with the air return cavity;

the evaporation side pipeline also comprises a first heat exchange device used for heating the separated liquid in the air return cavity and a second heat exchange device used for supercooling the condensed liquid in the lower heat exchange cavity.

As a further improvement of the device: the condensation evaporator also comprises a liquid inlet, a first spiral pipe group serving as a first heat exchange device, a throttle valve, a second spiral pipe group serving as a second heat exchange device, a regenerative cavity, a gas outlet pipe and an oil return capillary pipe;

the liquid inlet is communicated with the heat exchange tube assembly through a first spiral tube group, a throttle valve and a second spiral tube group in sequence;

the air return cavity is communicated with the heat return cavity through a pipeline, the first spiral pipe group is arranged in the heat return cavity, the inlet end of the air outlet pipe is communicated with the heat return cavity, one end of the oil return capillary pipe is communicated with the air outlet pipe, and the other end of the oil return capillary pipe is communicated with the bottom of the heat return cavity;

a guide plate positioned below the heat exchange tube assembly is also arranged in the upper heat exchange cavity, and the guide plate and the inner wall of the shell are enclosed to form a liquid outlet heat exchange cavity with an upper opening; the second spiral pipe group is arranged in the liquid outlet heat exchange cavity, and an inlet of the liquid outlet pipe is communicated with the liquid outlet heat exchange cavity.

As a further improvement of the device: the second spiral pipe group is connected with the heat exchange pipe assembly through a gas-liquid distributor, and outlets of the gas-liquid distributor are respectively connected with heat exchange pipes in the heat exchange pipe assembly in a one-to-one correspondence mode through guide pipes.

As a further improvement of the device: an ultrasonic oscillator is arranged in the gas-liquid distributor.

As a further improvement of the device: the heat exchange tube is vertically arranged, a spiral channel is arranged in the heat exchange tube, and vertical prismatic protrusions which are uniformly distributed on the circumference are arranged on the outer surface of the heat exchange tube.

As a further improvement of the device: the upper heat exchange cavity is also internally provided with a lower tube plate, and the bottom of the heat exchange tube assembly is arranged in the shell through the lower tube plate; and the lower tube plate is provided with a through hole.

As a further improvement of the device: the throttle valve collects the gas temperature and pressure signals in the gas outlet pipe and adjusts the opening degree of the throttle valve.

As a further improvement of the device: the upper tube plate is obliquely arranged, and an inlet of the pipeline is communicated with the bottom of the regenerative chamber.

As a further improvement of the device: the air inlet pipe is communicated with a rotary air diffuser arranged in the lower heat exchange cavity.

Compared with the prior art, the invention has the following beneficial effects: (1) the invention provides a special high-efficiency multifunctional integrated condensing evaporator for a cascade system, wherein exhaust gas at a low temperature side is condensed after the superheat degree is eliminated in a lower heat exchange cavity through gas-liquid mixing, so that the heat exchange area utilization rate of the condensing evaporator is higher, meanwhile, the superheat degree of returned gas and the supercooling degree of discharged liquid are improved by fully utilizing an evaporation side, the influence of temperature difference stress is eliminated, the heat exchange of the condensation side and the evaporation side is enhanced, the overall heat exchange performance of the condensing evaporator is greatly improved (higher than that of a flooded and gravity type liquid supply condensing evaporator), the filling amount is greatly reduced, the volume of the device is reduced, and the device has the functions of condensate supercooling and automatic oil return; (2) by supercooling the condensate at the condensation side and controlling the superheat degree after backheating at the evaporation side, the feasibility of remote liquid supply at the condensation side is provided, the evaporation side has certain air suction liquid digestion capacity, and the system reliability is improved.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a sectional view of an upper end portion of a heat exchange tube.

Fig. 3 is a schematic view of an upper end portion of a heat exchange tube.

Fig. 4 is a top view of a heat exchange tube.

Detailed Description

The technical scheme of the invention is explained in detail in the following with the accompanying drawings:

referring to fig. 1, the multifunctional integrated condensing evaporator of the cascade refrigeration system comprises a shell 1, wherein an upper tube plate 8 and a rectifying layer 5 are arranged in the shell 1 from top to bottom, and an inner cavity of the shell 1 is divided into an air return cavity, an upper heat exchange cavity and a lower heat exchange cavity from top to bottom. Wherein, the upper tube plate 8 is arranged by inclining 5 degrees.

The condensation evaporator also comprises an air inlet pipe 7 communicated with the lower heat exchange cavity and a liquid outlet pipe 19 communicated with the upper heat exchange cavity. Specifically, the air inlet pipe 7 is communicated with a rotary air diffuser 6 installed in the lower heat exchange cavity. A guide plate 17 positioned below the heat exchange tube assembly 2 is further arranged in the upper heat exchange cavity, a liquid outlet heat exchange cavity with an upper opening is formed by the guide plate 17 and the inner wall of the shell 1 in a surrounding mode, and an inlet of the liquid outlet tube 19 is communicated with the liquid outlet heat exchange cavity.

The condensation evaporator further comprises an evaporation side pipeline, and the evaporation side pipeline comprises a heat exchange pipe assembly 2 arranged in the upper heat exchange cavity. As shown in fig. 2 to 4, the heat exchange tube assembly 2 comprises a plurality of sets of vertically arranged heat exchange tubes, wherein spiral channels are arranged in the heat exchange tubes, and vertical prismatic protrusions are uniformly distributed on the outer surface of the heat exchange tubes. The upper end of the heat exchange tube assembly 2 penetrates through the upper tube plate 8 to be communicated with the air return cavity.

As shown in fig. 1, a lower tube plate 3 is further arranged in the upper heat exchange cavity, and the bottom of the heat exchange tube assembly 2 is mounted in the shell 1 through the lower tube plate 3; and a through hole is formed in the lower tube plate 3.

The evaporation side pipeline further comprises a liquid inlet, a first spiral pipe group 13, a throttle valve 16, a second spiral pipe group 18, a regenerative cavity 12, an air outlet pipe 10 and an oil return capillary pipe 11.

The liquid inlet is communicated with the heat exchange tube assembly 2 through a first spiral tube group 13, a throttle valve 16 and a second spiral tube group 18 in sequence. The second spiral tube group 18 is arranged in the liquid outlet heat exchange cavity.

Further, the second spiral tube group 18 is connected with the heat exchange tube assembly 2 through a gas-liquid distributor 14, and outlets of the gas-liquid distributor 14 are respectively connected with heat exchange tubes in the heat exchange tube assembly 2 in a one-to-one correspondence manner through guide tubes 4.

An ultrasonic oscillator 15 is arranged in the gas-liquid distributor 14.

The bottom of the gas return cavity is communicated with a heat return cavity 12 through a pipeline 9, the first spiral pipe group 13 is arranged in the heat return cavity 12, the inlet end of the gas outlet pipe 10 is communicated with the heat return cavity 12, one end of the oil return capillary pipe 11 is communicated with the gas outlet pipe 10, and the other end of the oil return capillary pipe is communicated with the bottom of the heat return cavity 12.

The throttle valve 16 collects the temperature and pressure signals of the gas in the gas outlet pipe 10 and adjusts the opening degree of the throttle valve.

The working process of the device is as follows:

condensation side: exhaust enters from the air inlet pipe 7, is uniformly scattered to the lower heat exchange cavity (below the liquid level) through the rotary type air diffuser 6, and is enabled to be fully contacted with gas and liquid through the rectifying layer 5, the exhaust carries out heat exchange in the gas-liquid mixing process, the exhaust superheat degree is eliminated, saturated steam is generated, and the heat exchanger is prevented from being damaged by temperature stress generated by the heat exchange pipe bundle. Saturated vapor above the rectifying layer 5 reaches the heat exchange tube assembly 2 through the through holes in the lower tube plate 3, is condensed and liquefied at the outer side of the heat exchange tube and is stored in the bottom space of the shell 1. The condensate at the bottom crosses the guide plate 17, passes through the space outside the second spiral tube group 18, is cooled and has increased supercooling degree, and is output from the liquid outlet tube 19 to supply liquid to the tail end.

Evaporation side: high-temperature liquid enters the first spiral tube bank 13 (is heated in the regenerative cavity 12), is throttled, depressurized and cooled through the throttle valve 16 (adopting superheat degree control), enters the second spiral tube bank 18 to be subcooled for condensed liquid, and then enters the gas-liquid distributor 14. Because the throttling state is a gas-liquid mixing state, in order to enhance the uniformity of gas-liquid mixing, an atomizing element, namely an ultrasonic oscillator 15, is adopted to fully atomize the liquid into droplets with the level of 1-3 microns, the droplets with the diameter are in a suspension state and are uniformly distributed in the cavity of the gas-liquid distributor 14, and then enter each heat exchange tube along with the guide tube 4 to exchange heat with the gas in the shell 1 and are evaporated into saturated gas. The heat exchange tube is internally provided with an internal spiral channel, so that the turbulent flow effect can be increased, and the heat exchange efficiency and the oil carrying capacity are improved. Saturated gas in the heat exchange tube enters the gas return cavity, and under the action of the inclined upper tube plate 8, the refrigeration oil and trace liquid in the gas are collected at the bottom of the gas return cavity, enter the heat return cavity 12 through the pipeline 9 and are heated by the first spiral tube group 13 until being evaporated. The refrigeration oil in the regenerative cavity 12 is stored at the bottom of the regenerative cavity 12, the saturated gas has a certain superheat degree after being heated by the first spiral tube group 13, and is discharged through the gas outlet pipe 10, and meanwhile, the refrigeration oil at the bottom of the regenerative cavity 12 is sucked into the gas outlet pipe 10 through the injection effect of the oil return capillary tube 11 and is output along with the gas. The throttle valve 16 collects the temperature and pressure signals of the gas in the outlet pipe 10 to adjust the opening.