阅读说明：本技术 一种蒸发器 (Evaporator ) 是由 杨锘 陈健勇 陈颖 罗向龙 黄锟腾 于 2021-08-20 设计创作，主要内容包括：一种蒸发器,包括平行设置的第一集流管和第二集流管、设于所述第一集流管和第二集流管之间的若干根连接管、蒸发器入口、蒸发器出口,所述第一集流管上设有相互独立的若干第一集流腔,所述第二集流管上设有相互独立的若干第二集流腔,若干第一集流腔与若干第二集流腔通过连接管相间连接形成蛇形通道,所述蒸发器入口及蒸发器出口分别设置在蛇形通道的入口及出口处,若干第一集流腔中除了首个第一集流腔外的至少一个腔体通过支路也与蒸发器入口连接。本发明中,工质在整个流动过程干度差异不大,使得蒸发过程中传热也比较均匀,传热系数维持在较高的水平。(The utility model provides an evaporator, includes parallel arrangement's first pressure manifold and second pressure manifold, locates a plurality of connecting pipes, evaporator entry, the evaporator export between first pressure manifold and the second pressure manifold, be equipped with a plurality of first manifolds of mutual independence on the first pressure manifold, be equipped with a plurality of second manifolds of mutual independence on the second pressure manifold, a plurality of first manifolds and a plurality of second manifolds are connected alternately through the connecting pipe and are formed serpentine channel, evaporator entry and evaporator export set up respectively in serpentine channel's entry and exit, and at least one cavity except first manifold in a plurality of first manifolds passes through the branch road and also is connected with the evaporator entry. In the invention, the dryness difference of the working medium in the whole flowing process is not large, so that the heat transfer in the evaporation process is relatively uniform, and the heat transfer coefficient is maintained at a higher level.)

1. The utility model provides an evaporator, its characterized in that, includes parallel arrangement's first pressure manifold (1) and second pressure manifold (2), locates a plurality of connecting pipes (3), evaporator entry (41), evaporator export (42) between first pressure manifold (1) and second pressure manifold (2), be equipped with a plurality of first manifolds of mutual independence on first pressure manifold (1), be equipped with a plurality of second manifolds of mutual independence on second pressure manifold (2), a plurality of first manifolds and a plurality of second manifolds are connected alternately through connecting pipe (3) and are formed snakelike passageway, evaporator entry (41) and evaporator export (42) set up respectively in snakelike passageway's entry and exit, and at least one cavity except first manifold in a plurality of first manifolds also is connected with evaporator entry (41) through the branch road.

2. An evaporator according to claim 1, further comprising an ejector operable to adjust the quality of the working fluid in at least two secondary collecting chambers of the secondary collecting main (2).

3. The evaporator according to claim 2, wherein the plurality of first manifolds on the first header (1) includes a first chamber (11), a second chamber (12), a third chamber (13) and a fourth chamber (14) which are sequentially arranged, the plurality of second manifolds on the second header (2) includes a first chamber (21), a second chamber (22) and a third chamber (23) which are sequentially arranged, the evaporator inlet (41) is communicated with the first chamber (11), the evaporator outlet (42) is communicated with the fourth chamber (14), and the evaporator inlet (41) is provided with a second branch (52) communicated with the second chamber (12) and a third branch (53) communicated with the third chamber (13).

4. The evaporator according to claim 3, wherein the ejector is a two-stage ejector (8), the two-stage ejector (8) comprises an ejector inlet (81), a first-stage injection inlet (82), a second-stage injection inlet (83) and an ejector outlet (84), a first branch (51) is arranged between the ejector inlet (81) and the evaporator inlet (41), a first passage (61) is arranged between the first-stage injection inlet (82) and the first chamber (21), a second passage (62) is arranged between the second-stage injection inlet (83) and the third chamber (23), and a third passage (63) is arranged between the ejector outlet (84) and the second chamber (22).

5. An evaporator according to claim 4, wherein the first branch (51), the second branch (52) and the third branch (53) are provided with a liquid blocking and venting device and a liquid phase regulating valve (71), and the first passage (61) and the second passage (62) are provided with a liquid blocking and venting device and a gas phase regulating valve (72).

6. An evaporator according to any one of claims 1 to 5 wherein flow equalization means for the mixed working fluid are provided in both the first and second headers.

7. An evaporator according to claim 6 wherein the flow equalization means in the first header comprises a riser (91) disposed between the inlet and outlet of the first header to divide the first header into an inlet chamber (901) and an outlet chamber, and a cross plate (92) disposed on the outlet chamber to divide the outlet chamber into an intermediate chamber (902) and an outlet chamber (903), wherein the riser (91) is provided with a mixing hole (911) for communicating the inlet chamber (901) with the intermediate chamber (902), the cross plate (92) is provided with a plurality of equalization holes (912), and the flow equalization means in the second header has the same structure as the flow equalization means in the first header.

8. An evaporator according to claim 7 wherein the mixing hole (911) is a waist circle and the equipartition hole (912) is a circle.

9. An evaporator according to claim 1, wherein the connecting tubes (3) are flat tubes, and the depth of the flat tubes extending into the first header (1) and the second header (2) is 6 mm.

10. The evaporator according to claim 9, wherein the flat tubes are perpendicular to the first collecting pipe (1), the flat tubes comprise a plurality of flat micro-channels (31), the flat micro-channels (31) are laid in a direction perpendicular to the axis of the first collecting pipe (1), the cross-section of the micro-channels (31) is square, each flat tube comprises 12 micro-channels (31) with the same size, and a fin (32) for increasing the heat exchange efficiency is arranged between two adjacent flat tubes.

Technical Field

The invention relates to the technical field of evaporator refrigeration, in particular to an evaporator.

Background

For refrigerating system, the evaporimeter is very important part, and the heat exchange efficiency of evaporimeter can influence whole refrigerating system's performance, and microthermal condensate liquid passes through the evaporimeter, carries out the heat exchange with external air, and gasification heat absorption reaches cryogenic effect. The microchannel evaporator is used as a novel efficient heat exchanger and has higher heat exchange efficiency, but because the distance between a runner inlet and each flat pipe is different, the flow velocity of a working medium flowing into the flat pipe is inconsistent, the phenomenon of uneven flow distribution exists, the phenomena of 'dry evaporation' or 'excessive liquid supply' and the like occur, the heat exchange condition of the evaporator is worsened, the temperature field distribution is uneven, and the heat exchange performance is obviously reduced. In addition, in the evaporation process, along with the increase of the dryness of the working medium, the heat transfer coefficient of the working medium is increased and then reduced, the fluctuation is large, and the heat transfer effect needs to be optimized.

Chinese patent publication No. CN209415844U discloses a double-flow-path microchannel evaporator with double liquid supply tubes and gas guide tubules, which includes a collecting header and a main header arranged at left and right intervals; the opposite sides of the confluence collecting pipe and the main collecting pipe are communicated through a plurality of flat pipes which are transversely distributed; the main collecting pipe is internally provided with a laterally distributed range baffle which divides the main collecting pipe into an inlet collecting pipe and an outlet collecting pipe; a liquid separating baffle is arranged in the inlet collecting pipe and divides the inlet collecting pipe into an upper cavity and a lower cavity; the upper cavity of the inlet header is communicated with the upper liquid supply pipe, and the lower cavity of the inlet header is communicated with the lower liquid supply pipe; the upper part of the right side of the outlet header is communicated with an exhaust pipe through a one-way valve; the top of the confluence collecting pipe is communicated with the exhaust pipe through an air guide thin pipe.

But above-mentioned scheme trades the better heat transfer effect of upper cavity through the heat transfer effect of sacrificing lower cavity, moreover, because the air guide tubule is with some gas row to the blast pipe, makes the flat pipe working medium flow that the export collector corresponds reduce, and the evaporimeter heat transfer volume reduces. Meanwhile, the scheme can not realize the accurate regulation and control of the dryness of the working medium, and because the heat transfer coefficient is increased and then reduced along with the increase of the dryness of the working medium in the evaporation process, the overhigh or overlow dryness is not beneficial to the heat transfer of the working medium, and the dryness of the working medium is most beneficial to the heat exchange between 0.6 and 0.8.

Disclosure of Invention

The invention aims to overcome the defect that the heat exchange effect of an evaporator in the prior art is not good enough, and provides an evaporator. In the invention, the dryness difference of the working medium in the whole flowing process is not large, so that the heat transfer in the evaporation process is relatively uniform, and the heat transfer coefficient is maintained at a higher level.

The purpose of the invention can be achieved by adopting the following technical scheme:

the utility model provides an evaporator, includes parallel arrangement's first pressure manifold and second pressure manifold, locates a plurality of connecting pipes, evaporator entry, the evaporator export between first pressure manifold and the second pressure manifold, be equipped with a plurality of first manifolds of mutual independence on the first pressure manifold, be equipped with a plurality of second manifolds of mutual independence on the second pressure manifold, a plurality of first manifolds and a plurality of second manifolds are connected alternately through the connecting pipe and are formed serpentine channel, evaporator entry and evaporator export set up respectively in serpentine channel's entry and exit, and at least one cavity except first manifold in a plurality of first manifolds passes through the branch road and also is connected with the evaporator entry.

Working medium enters from an inlet of the evaporator and flows back and forth between the first collecting pipe and the second collecting pipe through the connecting pipe, namely the working medium enters into a first collecting chamber, then enters into a second collecting chamber communicated with the connecting pipe through the connecting pipe of the first collecting chamber, then enters into the next first collecting chamber through the connecting pipe again, and finally enters into the next second collecting chamber through the connecting pipe, so that the flow mode of the working medium is snakelike. Except that the first collecting cavity is directly connected with the inlet of the evaporator, at least one branch communicated with other first collecting cavities is arranged on the inlet of the evaporator, the working medium at the inlet of the evaporator directly enters a cavity in the middle of the working medium flowing process, the dryness of the working medium at the position is directly regulated and controlled, and if the number of the branches is large, the dryness of the whole working medium flow is uniform.

Furthermore, the device also comprises an ejector which can be used for adjusting the dryness of the working medium in at least two second collecting cavities on the second collecting pipe. The first collecting pipe is used for mixing working media at the inlet of the evaporator through a plurality of branch circuits and then enters the first collecting pipe, and the ejector is used for adjusting the dryness of the working media in the second collecting cavity on the second collecting pipe. The ejector can be a single-stage ejector, and gaseous working media in the second collecting cavity behind the working medium flow are allocated to the second collecting cavity in the front; the ejector may be a two-stage ejector or a multi-stage ejector such as a three-stage ejector.

Furthermore, the plurality of first collecting cavities on the first collecting pipe comprise a first cavity, a second cavity, a third cavity and a fourth cavity which are sequentially arranged, the plurality of second collecting cavities of the second collecting pipe comprise a first chamber, a second chamber and a third chamber which are sequentially arranged, an evaporator inlet is communicated with the first cavity, an evaporator outlet is communicated with the fourth cavity, and a second branch communicated with the second cavity and a third branch communicated with the third cavity are arranged on the evaporator inlet.

Working medium enters the evaporator from the evaporator inlet, the working medium is divided into three paths from the evaporator inlet, one path enters the first cavity in the first collecting pipe, the other path enters the second cavity through the second branch, and the other path enters the third cavity through the third branch. The working medium entering the first cavity enters the first chamber in the second collecting pipe through the connecting pipe and then enters the second cavity through the connecting pipe; the working medium entering the second cavity from the connecting pipe is mixed with the working medium entering the second cavity from the second branch and then enters the second chamber through the connecting pipe; the working medium entering the second chamber enters the third chamber through the connecting pipe, is mixed with the working medium entering through the third branch, and then enters the third chamber through the connecting pipe; the working medium entering the third chamber enters the fourth chamber through the connecting pipe, and then flows out of the evaporator through the evaporator outlet communicated with the fourth chamber to enter the next working link. The second branch and the third branch only allow liquid to pass through, liquid is distributed and divided through the second branch and the third branch, after the working medium enters the evaporator from the inlet, the working medium does not completely enter the first cavity, but is distributed to each link in the working medium flowing process through the branches, the dryness of the working medium in the first cavity in which the liquid working medium flows out is improved, and the dryness of the working medium in the second cavity and the third cavity in which the liquid working medium flows in is reduced. Therefore, the initial dryness of the evaporation process can be improved, and the final dryness of the evaporation process can be reduced, so that the dryness of the working medium in the whole process is uniform and maintained at a better level, the heat transfer coefficient is maintained at a higher position, and the heat exchange capacity of the evaporator is improved. Therefore, the problems that the heat transfer coefficient of a common evaporator fluctuates greatly in the heat exchange process, the heat exchange effect is not uniform and the like are solved.

Further, the ejector is a two-stage ejector, the two-stage ejector comprises an ejector inlet, a one-stage injection inlet, a two-stage injection inlet and an ejector outlet, a first branch is arranged between the ejector inlet and the evaporator inlet, a first passage is arranged between the one-stage injection inlet and the first chamber, a second passage is arranged between the two-stage injection inlet and the third chamber, and a third passage is arranged between the ejector outlet and the second chamber.

The working medium is divided into three paths at the inlet of the evaporator, and one path of the working medium enters the inlet of the ejector of the double-stage ejector, namely, a part of the working medium at the inlet of the evaporator enters the ejector through the first branch path. Meanwhile, the working medium of the first chamber enters the double-stage ejector through the first passage, and the working medium of the third chamber enters the double-stage ejector through the second passage. The working medium entering the double-stage ejector from the first branch, the first passage and the second passage is mixed and ejected, and enters the second chamber through a third passage communicated with the outlet of the ejector. The first branch passage allows only liquid to pass through, and the first and second passages allow only gas to pass through. The first passage and the second passage are connected with the two-stage ejector, and injection is performed by utilizing the pressure difference between the inlet working medium and the injection working medium, so that the change of the internal dryness of the evaporator is realized. In order to fully utilize saturated gas-phase working media with different pressures in the evaporator, a second-stage ejector is additionally arranged behind a single-stage ejector to form a double-stage ejector, mixed fluid discharged by the first-stage ejector is used as working fluid of the second-stage ejector, and multiple strands of gas-phase working media can be ejected to adjust the dryness in the evaporator. Compared with the method that the gas-phase working medium is directly pumped out of the evaporator, the method does not participate in the heat exchange of the subsequent flow, the gas-phase working medium can be fully utilized by adopting the two-stage ejector, and the performance better than that of the traditional solution is obtained.

Further, the first branch, the second branch and the third branch are respectively provided with a gas blocking and liquid passing device and a liquid phase regulating valve, and the first passage and the second passage are respectively provided with a gas blocking and liquid passing device and a gas phase regulating valve. The liquid blocking and ventilating device only allows liquid to pass through and blocks gas, and the liquid blocking and ventilating device only allows gas to pass through and blocks liquid, so that the first branch, the second branch and the third branch all allow liquid to pass through, and the first passage and the second passage only allow gas to pass through. The liquid phase regulating valve is used for regulating the flow of liquid passing through the first branch, the second branch and the third branch, and the gas phase regulating valve is used for regulating the flow of gas passing through the first passage and the second passage.

Furthermore, flow uniform distribution devices for mixing working media are arranged in the first collecting cavity and the second collecting cavity. The flow uniform distribution device can enable the working medium to uniformly pass through the connecting pipes, and also can enable the working medium entering from the passage or the branch to be fully mixed with the working medium entering from the connecting pipes, and the flow of the working medium flowing into each connecting pipe is consistent, so that the purpose of uniform heat exchange is achieved.

Furthermore, the flow uniform distribution device in the first collecting cavity comprises a vertical plate and a transverse plate, wherein the vertical plate is arranged between the inlet and the outlet of the first collecting cavity and divides the first collecting cavity into an inlet cavity and an outlet cavity, the transverse plate is arranged on the outlet cavity and divides the outlet cavity into an intermediate cavity and an outlet cavity, a mixing hole for communicating the inlet cavity with the intermediate cavity is formed in the vertical plate, a plurality of uniform distribution holes are formed in the transverse plate, and the flow uniform distribution device in the second collecting cavity is identical to the flow uniform distribution device in the first collecting cavity in structure.

The working medium firstly enters the inlet cavity, then enters the middle cavity through the mixing hole, and then flows into the connecting pipe through the outlet cavity. In the first collecting cavity, the working medium flowing out of the connecting pipe and the working medium from the evaporator inlet or the ejector are mixed in the inlet cavity of the first collecting cavity and enter the middle cavity through the mixing hole. Then, the working medium enters the outlet cavity through the uniform distribution holes, and the positions of the uniform distribution holes can correspond to the inlets of the connecting pipes, so that the working medium can be uniformly distributed in the connecting pipes.

Furthermore, the mixing holes are waist-shaped, and the uniform distribution holes are circular.

Furthermore, the connecting pipe is a flat pipe, and the depth of the flat pipe extending into the first collecting pipe and the second collecting pipe is 6 mm. The flat pipe insertion depth in the collecting pipe can influence flow distribution, and the flow distribution is uneven due to too large or too small invasion distance, so that the flow is uniformly distributed by adjusting the flat pipe insertion depth.

Furthermore, the flat tubes are perpendicular to the first collecting pipe and comprise a plurality of tiled microchannels, the tiling direction of the microchannels is perpendicular to the axis of the first collecting pipe, the cross section of each microchannel is square, each flat tube comprises 12 microchannels with the same size, and fins for increasing the heat exchange efficiency are arranged between every two adjacent flat tubes. Four flat pipes are arranged in the first chamber, the second chamber, the third chamber, the first chamber, the second chamber and the third chamber, a uniform distribution hole can be arranged under each corresponding micro-channel on the transverse plate, two rows of uniform distribution holes can also be arranged along the arrangement direction of the micro-channels, each row of uniform distribution holes is positioned in the middle of two corresponding flat pipes, and each row of uniform distribution holes comprises three uniform distribution holes.

Further, the evaporator comprises a first auxiliary header and a second auxiliary header, wherein the first header is used for integrating the second branch and the third branch with the evaporator body into a whole, the second auxiliary header is used for integrating the first passage, the second passage and the third passage with the evaporator into a whole, and the evaporator is convenient to popularize and sell as a product due to the integrated design.

Compared with the prior art, the invention has the beneficial effects that:

(1) the working medium makes a round trip many times between first pressure manifold and second pressure manifold, passes through in flat pipe many times, makes the evaporimeter form the heat transfer of many processes, and heat exchange efficiency promotes greatly.

(2) Through the distribution of the branch at the inlet of the evaporator and the ejector, the initial dryness of the evaporation process is improved, the final dryness is reduced, the heat transfer coefficient is maintained at a higher position, and the heat exchange capacity of the evaporator is improved.

(3) Two-stage ejectors are adopted to respectively eject two gas-phase working media, an external power device is not needed, the heat exchange efficiency of the micro-channel evaporator is improved on the premise of energy conservation, and the problems that the heat transfer coefficient of a common evaporator is large in fluctuation in the heat exchange process, the heat exchange effect is uneven and the like are solved.

(4) The flow uniform distribution device enables the working medium states to be fully mixed, and the flow flowing into each flat pipe is consistent, so that the purpose of uniform heat exchange is achieved.

Drawings

Fig. 1 is a schematic view of the internal structure of the present invention.

Fig. 2 is a schematic structural diagram of the flow uniform distribution device of the invention.

FIG. 3 is a schematic diagram of the dual stage ejector of the present invention.

Fig. 4 is a schematic structural view of the flat tube of the present invention.

FIG. 5 is a graph showing the change of the heat transfer coefficient with the evaporation process in example 1 of the present invention.

The graphic symbols are illustrated as follows:

1-first collecting pipe, 11-first cavity, 12-second cavity, 13-third cavity, 14-fourth cavity, 2-second collecting pipe, 21-first cavity, 22-second cavity, 23-third cavity, 3-connecting pipe, 31-microchannel, 32-fin, 41-evaporator inlet, 42-evaporator outlet, 51-first branch, 52-second branch, 53-third branch, 61-first passage, 62-second passage, 63-third passage, 71-liquid phase regulating valve, 72-gas phase regulating valve, 8-double-stage ejector, 81-ejector inlet, 82-first stage injection inlet, 83-second stage injection inlet, 84-ejector outlet, 901-inlet cavity, 902-middle cavity, 903-outlet cavity, 91-vertical plate, 911-mixing hole, 912-uniform distribution hole and 92-transverse plate.

Detailed Description

The present invention will be further described with reference to the following embodiments. Wherein the showings are for the purpose of illustration only and are shown by way of illustration only and not in actual form, and are not to be construed as limiting the present patent; to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.

The same or similar reference numerals in the drawings of the embodiments of the present invention correspond to the same or similar components; in the description of the present invention, it should be understood that if there is an orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", etc. based on the orientation or positional relationship shown in the drawings, it is only for convenience of describing the present invention and simplifying the description, but it is not intended to indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and are not to be construed as limiting the present patent, and the specific meaning of the terms may be understood by those skilled in the art according to specific circumstances.

Example 1

As shown in fig. 1 to 5, an evaporator includes a first collecting pipe 1 and a second collecting pipe 2, which are arranged in parallel, a plurality of connecting pipes 3, an evaporator inlet 41, and an evaporator outlet 42, which are arranged between the first collecting pipe 1 and the second collecting pipe 2, wherein the first collecting pipe 1 is provided with a plurality of mutually independent first manifolds, the second collecting pipe 2 is provided with a plurality of mutually independent second manifolds, the plurality of first manifolds and the plurality of second manifolds are alternately connected through the connecting pipes 3 to form a serpentine channel, the evaporator inlet 41 and the evaporator outlet 42 are respectively arranged at the inlet and the outlet of the serpentine channel, and at least one of the plurality of first manifolds except for a first manifold is also connected with the evaporator inlet 41 through a branch.

Working medium enters from an evaporator inlet 41 and flows back and forth between the first collecting pipe 1 and the second collecting pipe 2 through the connecting pipe 3, namely the working medium enters a first collecting cavity, then enters a second collecting cavity communicated with the connecting pipe 3 through the connecting pipe of the first collecting cavity, then enters the next first collecting cavity through the connecting pipe 3 again, and then enters the next second collecting cavity through the connecting pipe 3, so that the flow mode of the working medium is snakelike. Except that the first collecting cavity is directly connected with the evaporator inlet 41, at least one branch communicated with other first collecting cavities is arranged on the evaporator inlet 41, the working medium at the evaporator inlet 41 directly enters a cavity in the middle of the working medium flowing process, the dryness of the working medium at the position is directly regulated and controlled, and if the number of the branches is large, the dryness of the whole working medium flow is uniform.

As shown in fig. 1 to 5, the plurality of first manifolds on the first collecting pipe 1 include a first chamber 11, a second chamber 12, a third chamber 13, and a fourth chamber 14, which are sequentially arranged, the plurality of second manifolds on the second collecting pipe 2 include a first chamber 21, a second chamber 22, and a third chamber 23, which are sequentially arranged, the evaporator inlet 41 is communicated with the first chamber 11, the evaporator outlet 42 is communicated with the fourth chamber 14, and the evaporator inlet 41 is provided with a second branch 52 communicated with the second chamber 12, and a third branch 53 communicated with the third chamber 13.

Working medium enters the evaporator from the evaporator inlet 41, the working medium is divided into three paths from the evaporator inlet 41, one path enters the first cavity 11 in the first collecting pipe 1, the other path enters the second cavity 12 through the second branch 52, and the other path enters the third cavity 13 through the third branch 53. The working medium entering the first cavity 11 enters the first chamber 21 in the second collecting pipe 2 through the connecting pipe 3, and then enters the second cavity 12 through the connecting pipe 3; the working medium entering the second cavity 12 from the connecting pipe 3 is mixed with the working medium entering the second cavity 12 from the second branch 52, and then enters the second chamber 22 through the connecting pipe 3; the working medium entering the second chamber 22 enters the third chamber 13 through the connecting pipe 3, then is mixed with the working medium entering through the third branch 53, and then enters the third chamber 23 through the connecting pipe 3; the working medium entering the third chamber 23 enters the fourth chamber 14 through the connecting pipe 3, and then flows out of the evaporator through the evaporator outlet 42 communicated with the fourth chamber 14 to enter the next working link. The second branch 52 and the third branch 53 only allow liquid to pass through, liquid is distributed and divided through the second branch 52 and the third branch 53, after the working medium enters the evaporator from the inlet, the working medium does not completely enter the first cavity 11, but is distributed to each link in the working medium flowing process through the branches, the dryness of the working medium in the first cavity 11 where the liquid working medium flows out is improved, and the dryness of the working medium in the second cavity 12 and the third cavity 13 where the liquid working medium flows in is reduced. Therefore, the initial dryness of the evaporation process can be improved, and the final dryness of the evaporation process can be reduced, so that the dryness of the working medium in the whole process is uniform and maintained at a better level, the heat transfer coefficient is maintained at a higher position, and the heat exchange capacity of the evaporator is improved. Therefore, the problems that the heat transfer coefficient of a common evaporator fluctuates greatly in the heat exchange process, the heat exchange effect is not uniform and the like are solved.

As shown in fig. 1 to 5, the system further includes an ejector capable of adjusting the quality of the working fluid in at least two second collecting chambers of the second collecting pipe 2. The first collecting pipe 1 is used for adjusting working medium at the inlet 41 of the evaporator to enter the first collecting pipe 1 through a plurality of branch circuits, and the ejector is used for adjusting the dryness of the working medium in the second collecting cavity on the second collecting pipe 2.

As shown in fig. 1 to 5, the ejector is a two-stage ejector 8, the two-stage ejector 8 includes an ejector inlet 81, a first-stage injection inlet 82, a second-stage injection inlet 83, and an ejector outlet 84, a first branch 51 is provided between the ejector inlet 81 and the evaporator inlet 41, a first passage 61 is provided between the first-stage injection inlet 82 and the first chamber 21, a second passage 62 is provided between the second-stage injection inlet 83 and the third chamber 23, and a third passage 63 is provided between the ejector outlet 84 and the second chamber 22.

The working fluid is divided into three paths at the evaporator inlet 41 and also divided into one path to enter the ejector inlet 81 of the two-stage ejector 8, namely, a part of the working fluid at the evaporator inlet 41 enters the ejector through the first branch 51. Meanwhile, the working medium in the first chamber 21 enters the double-stage ejector through the first passage 61, and the working medium in the third chamber 23 enters the double-stage ejector through the second passage 62. The working fluid entering the dual stage injector from the first branch 51, the first passage 61 and the second passage 62 is mixed and injected into the second chamber 22 through the third passage 63 communicating with the injector outlet 84. The arrows shown in the drawings indicate the direction of flow of the working substance. The first branch 51 allows only liquid to pass through, and the first and second passages 61 and 62 allow only gas to pass through. The first passage 61 and the second passage 62 are connected with the double-stage ejector 8, and ejection is performed by utilizing the pressure difference between inlet working media and ejection working media, so that the change of the dryness inside the evaporator is realized. In order to fully utilize saturated gas-phase working media with different pressures in the evaporator, a second-stage ejector is additionally arranged behind the single-stage ejector to form a double-stage ejector 8, mixed fluid discharged by the first-stage ejector is used as working fluid of the second-stage ejector, and multiple strands of gas-phase working media can be ejected to adjust the dryness in the evaporator. Compared with the method that the gas-phase working medium is directly pumped out of the evaporator, the method does not participate in the heat exchange of the subsequent flow, the gas-phase working medium can be fully utilized by adopting the two-stage ejector 8, and the performance better than that of the traditional solution is obtained.

As shown in fig. 1 to 5, the first branch 51, the second branch 52, and the third branch 53 are each provided with a liquid blocking and venting device and a liquid phase regulating valve 71, and the first passage 61 and the second passage 62 are each provided with a liquid blocking and venting device and a gas phase regulating valve 72. The liquid blocking and venting device only allows liquid to pass through and blocks gas, and the liquid blocking and venting device only allows gas to pass through and blocks liquid, so that the first branch 51, the second branch 52 and the third branch 53 all allow liquid to pass through, and the first passage 61 and the second passage 62 only allow gas to pass through. The gas and liquid blocking and ventilating device is a partition plate with holes, and the gas and liquid blocking and ventilating device is a mesh plate with a mesh structure. The liquid phase regulating valve 71 is used for regulating the flow rate of the liquid passing through the first branch 51, the second branch 52 and the third branch 53, and the gas phase regulating valve 72 is used for regulating the flow rate of the gas passing through the first passage 61 and the second passage 62.

As shown in fig. 1 to 5, in this embodiment, flow rate uniform distribution devices for mixing working media are respectively disposed in the first chamber 11, the second chamber 12, the third chamber 13, the first chamber 21, the second chamber 22, and the third chamber 23. The flow uniform distribution device can ensure that the working medium entering from the passage or the branch is fully mixed with the working medium entering from the connecting pipes 3, the flow of the working medium entering into each connecting pipe 3 is consistent, and the purpose of uniform heat exchange is achieved.

As shown in fig. 1 to 5, the flow uniform distribution device in the second chamber 12 includes a vertical plate 91 disposed between the inlet and the outlet of the second chamber 12 to divide the second chamber 12 into an inlet chamber 901 and an outlet chamber, and a horizontal plate 92 disposed on the outlet chamber to divide the outlet chamber into a middle chamber 902 and an outlet chamber 903, the vertical plate 91 is provided with a mixing hole 911 for communicating the inlet chamber 901 and the middle chamber 902, the horizontal plate 92 is provided with a plurality of uniform distribution holes 912, and the flow uniform distribution devices in the first chamber 11, the third chamber 13, the first chamber 21, the second chamber 22, and the third chamber 23 have the same structure as the flow uniform distribution device in the second chamber 12.

The working medium first enters the inlet chamber 901, then enters the intermediate chamber 902 through the mixing hole 911, and then flows into the connecting tube 3 through the outlet chamber 903. In the second cavity 12, the working medium flowing out of the connecting pipe 3 and the working medium flowing out of the second branch 52 are mixed in the inlet cavity 901 of the second cavity 12 and enter the middle cavity 902 through the mixing hole 911, and because the area of the opening of the mixing hole 911 is small, the flow velocity of the working medium is increased, and the gas-liquid two-phase working medium is not easy to separate. Then, the working medium enters the outlet cavity 903 through the uniform distribution holes 912, and the positions of the uniform distribution holes 912 can correspond to the inlets of the connecting pipes 3, so that the working medium can be uniformly distributed in the connecting pipes 3.

As shown in fig. 1 to 5, the mixing hole 911 is a discoid shape, and the uniform distribution hole 912 is a circular shape.

As shown in fig. 1 to 5, the connecting pipe 3 is a flat pipe, and the depth of the flat pipe extending into the first collecting pipe 1 and the second collecting pipe 2 is 6 mm. The flat pipe insertion depth in the collecting pipe can influence flow distribution, and the flow distribution is uneven due to too large or too small invasion distance, so that the flow is uniformly distributed by adjusting the flat pipe insertion depth.

As shown in fig. 1 to 5, the flat tubes are perpendicular to the first collecting pipe 1, the flat tubes include a plurality of micro channels 31 that are tiled, a tiling direction of the micro channels 31 is perpendicular to an axis of the first collecting pipe 1, a cross section of each micro channel 31 is square, each flat tube includes 12 micro channels 31 that are identical in size, and a fin 32 for increasing heat exchange efficiency is disposed between two adjacent flat tubes. Four flat pipes are arranged in the first chamber 11, the second chamber 12, the third chamber 13, the first chamber 21, the second chamber 22 and the third chamber 23, the uniform distribution holes 912 in the transverse plate 92 can be provided with one uniform distribution hole 912 under each corresponding micro-channel 31, or two rows of uniform distribution holes 912 can be arranged along the arrangement direction of the micro-channels 31, each row of uniform distribution holes 912 is positioned between the two corresponding flat pipes, and each row of uniform distribution holes 912 comprises three uniform distribution holes 912.

As shown in fig. 1 to 5, the evaporator further comprises a first auxiliary header and a second auxiliary header, wherein the first auxiliary header is used for integrating the second branch 52 and the third branch 53 with the evaporator body, and the second auxiliary header is used for integrating the first passage 61, the second passage 62 and the third passage 63 with the evaporator body, so that the integrated design facilitates the evaporator to be popularized and sold as a product.

As shown in fig. 1 to 5, a first flow path is formed from the first chamber 11 to the first chamber 21, a second flow path is formed from the first chamber 21 to the second chamber 12, a third flow path is formed from the second chamber 12 to the second chamber 22, a fourth flow path is formed from the second chamber 22 to the third chamber 13, a fifth flow path is formed from the third chamber 13 to the third chamber 23, and a sixth flow path is formed from the third chamber 23 to the fourth chamber 14, and the change of the heat transfer coefficient with the evaporation process is shown in fig. 5, in which the broken lines are the heat transfer coefficients between the respective flow paths when the first branch 51, the second branch 52, the third branch 53, the first passage 61, the second passage 62, and the third passage 63 are not provided, and the solid lines are the heat transfer coefficients of the respective flow paths in the evaporator in this embodiment.

Example 2

This embodiment is similar to embodiment 1 except that in this embodiment, the gas phase regulating valve 72 on the first passage 61 is normally closed, or the first passage 61 is not provided, i.e., the injector is a single-stage injector. The working fluid in the first chamber 21 can be adjusted to a smaller extent, and the first passage 61 may not be provided in order to make the device more compact.

Example 3

The embodiment is similar to embodiment 1, except that in this embodiment, the first passage 61 does not communicate the first chamber 21 with the first-stage injection inlet 82, the third passage 63 does not communicate the second chamber 22 with the injector outlet 84, but the first passage 61 communicates the second chamber 22 with the injection inlet so that the working medium in the second chamber 22 enters the two-stage injector 8, and the third passage 63 communicates the first chamber 21 with the injector outlet 84 so that the working medium in the injector is ejected into the first chamber 21. Because the dryness is constantly promoted when working medium passes through the flat pipe, if the dryness is not provided with the first branch 51, the second branch 52, the third branch 53, the first passage 61, the second passage 62 and the third passage 63, the dryness is increased a little every time the dryness of the working medium passes through the flat pipe, and the dryness among the first chamber 21, the second chamber 22 and the third chamber 23 is gradually promoted. In order to balance the dryness among the first chamber 21, the second chamber 22 and the third chamber 23, the gas in the second chamber 22 and the third chamber 23 is pumped and adjusted into the first chamber 21 through the ejector, so that the dryness of the working medium in the previous process is improved, and the dryness fluctuation of the working medium in the whole process in the evaporator is not too large.

Example 4

The present embodiment is similar to embodiment 1, except that in the present embodiment, a fifth cavity is further disposed on the first collecting pipe 1, a fourth chamber is further disposed on the second collecting pipe 2, the evaporator outlet 42 is disposed on the fifth cavity, a fourth branch is further disposed between the evaporator inlet 41 and the fourth cavity 14, and a gas and liquid blocking device and a liquid regulating valve 71 are also disposed on the fourth branch. And flow uniform distribution devices are also arranged in the fourth cavity and the fourth chamber. A seventh process is performed between the fourth cavity 14 and the fourth chamber, and an eighth process is performed between the fourth chamber and the fifth cavity.

It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.