Liquid distribution device and falling film evaporator

Abstract

The application provides a liquid distribution device and a falling film evaporator. The liquid distribution device comprises a flow equalizing assembly, the flow equalizing assembly comprises a first flow channel, a plurality of baffles are installed in the first flow channel, and the plurality of baffles are arranged in a spaced manner and opposite to each other along the first flow channel, so that the falling film evaporator has excellent refrigerant distribution capacity and can uniformly distribute refrigerant to achieve the purpose of high-efficiency refrigeration.

Description

TECHNICAL FIELD

[0001] The present application relates to the evaporator technical field, and particularly relates to a liquid distribution device and falling film evaporator. BACKGROUND

[0002] The tube and shell evaporator, one of the core components of the commercial water chiller, is crucial to the performance of the unit. The tube and shell evaporator commonly used at present is divided into the full-liquid type and the falling film type. The former is to perform pool boiling heat exchange by immersing the heat exchange tube in the liquid refrigerant, while the latter is to perform evaporation heat exchange by using the liquid refrigerant dripping on the outer surface of the heat exchange tube in each row, which has two heat exchange forms of nucleate boiling and convective heat exchange. Due to the different heat exchange mechanisms, the structure and performance of the two types are different, and the falling film evaporator gradually becomes the focus of research due to the advantages of high heat exchange efficiency, high evaporation temperature, low refrigerant charge, etc.

[0003] For the falling film evaporator, the specific working principle is as follows: the gas-liquid mixed refrigerant passing through the throttling device enters the evaporator from the inlet connection pipe, and then the liquid refrigerant is uniformly dripped on the outer surface of the heat exchange tube by the liquid distribution device to form a liquid film from top to bottom to perform heat exchange with the fluid in the tube, and a small amount of liquid refrigerant not consumed in the above heat exchange process will accumulate at the bottom of the cylinder to form a liquid pool to perform evaporation heat exchange with the fluid in the heat exchange tube at this place, so as to fully utilize the refrigerant to achieve high-efficiency refrigeration. In the above process, whether the liquid refrigerant can be uniformly distributed is a key factor affecting the heat exchange performance of the evaporator.

[0004] The commonly used liquid distribution device at present mainly adopts a multilayer orifice plate to gradually distribute the liquid until the refrigerant is distributed on the outer surface of the heat exchange tube. Due to the high flow rate of the refrigerant entering the evaporator from the inlet connection pipe, the orifice plate of the existing liquid distribution device is at risk of being damaged, and under the continuous impact of the high-speed refrigerant, the liquid distribution device will be deformed and shaken to a certain extent. At the same time, the gaseous refrigerant cannot be discharged in time, which will seriously interfere with the liquid distribution process of the liquid refrigerant.

[0005] Therefore, a new type of liquid distribution device needs to be designed to have excellent refrigerant distribution capacity. SUMMARY

[0006] In order to solve the above problems, the present application provides a liquid distribution device and falling film evaporator, which has excellent refrigerant distribution capacity.

[0007] The liquid distribution device provided by the present application comprises a liquid distribution assembly, wherein the liquid distribution assembly comprises a first flow channel, and a plurality of baffles are installed in the first flow channel, and the plurality of baffles are arranged in pairs and spaced apart along the first flow channel.

[0008] As a further optimization of the present invention, it also includes a membrane assembly connected to the flow equalization assembly, the membrane assembly including a cavity in which a first liquid distribution plate and a second liquid distribution plate are installed.

[0009] As a further optimization of the present invention, the flow equalization component further includes a second flow channel, which is arranged around the periphery of the first flow channel and is connected to the first flow channel and the cavity respectively.

[0010] As a further optimization of the present invention, the first flow channel is composed of a side plate, a bottom plate, and a top cover, and the second flow channel is composed of a side plate, a side plate, a bottom plate, and a side cover; the side plate includes a first side plate and a second side plate, and the first side plate and the second side plate are tightly connected.

[0011] As a further optimization of the present invention, the top cover is provided with a second opening, and a gas-liquid filter screen is installed on the second opening.

[0012] As a further optimization of the present invention, an anti-impact platform is also installed in the first flow channel, and the height of the anti-impact platform is greater than the height of the baffle plate.

[0013] As a further optimization of the present invention, a first aperture connected to the second flow channel is provided on the second side plate which is arranged opposite to the anti-impact platform.

[0014] As a further optimization of the present invention, the sum of the lengths of two adjacent baffles, L1+L2, is greater than the length L3 of the second side plate.

[0015] As a further optimization of the present invention, the side plate is provided with a plurality of through holes that communicate with the film assembly.

[0016] As a further optimization of the present invention, the cavity is composed of a sealing plate and a frame, and the sealing plate has a second aperture that matches the flow equalization component. The flow equalization component is embedded in the second aperture and communicates with the cavity.

[0017] As a further optimization of the present invention, the first liquid distribution plate and the second liquid distribution plate are provided with multiple openings.

[0018] A falling film evaporator includes a cylindrical body, on which a liquid inlet pipe, an air outlet pipe, and a baffle are installed. Multiple heat exchange tubes are arranged inside the baffle. The evaporator also includes the aforementioned liquid distribution device, which is installed inside the cylindrical body and connected to the liquid inlet pipe and the air outlet pipe. The heat exchange tubes are arranged below the liquid distribution device.

[0019] As a further optimization of the present invention, the openings of the second liquid distribution plate are uniformly arranged along the axial direction directly above each heat exchange tube.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] The present invention discloses a liquid distribution device for uniform flow, which includes a flow equalization component. The flow equalization component includes a first flow channel, in which multiple baffles are installed. The multiple baffles are arranged opposite to each other along the first flow channel and at intervals, so that the falling film evaporator has excellent refrigerant distribution capability and can evenly distribute the refrigerant to achieve the purpose of efficient cooling.

[0022] The present invention provides a good anti-refrigerant impact effect for the falling film evaporator by installing an anti-impact platform in the first flow channel. Attached Figure Description

[0023] The invention will now be described in more detail with reference to embodiments and the accompanying drawings.

[0024] Figure 1 This is a schematic diagram of the falling film evaporator described in this invention;

[0025] Figure 2 This is a cross-sectional view of the liquid distribution device according to the present invention;

[0026] Figure 3 This is a schematic diagram of the flow equalization component described in this invention;

[0027] Figure 4 This is a flow diagram of the liquid refrigerant in the flow equalization component described in this invention.

[0028] In the above figures, 1. Liquid inlet pipe; 2. Cylinder body; 3. Flow equalization assembly; 31. Anti-impact platform; 32. Baffle plate; 33. Side plate; 3301. First side plate; 3302. Second side plate; 34. Side plate; 35. Bottom plate; 36. Gas-liquid filter screen; 37. Top cover; 38. Side cover; 4. Membrane assembly; 41. Sealing plate; 42. Frame; 43. First liquid distribution plate; 44. Second liquid distribution plate; 5. Heat exchange tube; 6. Baffle; 7. Gas outlet pipe.

[0029] In the accompanying drawings, the same parts use the same reference numerals. The drawings are not drawn to scale. Detailed Implementation

[0030] The invention will now be further described with reference to the accompanying drawings.

[0031] like Figures 1-4As shown, the present invention provides a falling film evaporator, including a cylindrical body 2, on which a liquid inlet pipe 1, an outlet pipe 7, and a baffle 6 are installed. Multiple heat exchange tubes 5 are arranged inside the baffle 6. The evaporator also includes a liquid distribution device, which is installed inside the cylindrical body 2 and connected to the liquid inlet pipe 1 and the outlet pipe 7. The heat exchange tubes 5 are arranged below the liquid distribution device, thereby achieving efficient refrigeration by fully utilizing the refrigerant.

[0032] The liquid distribution device includes a flow equalization component 3, which includes a first flow channel. Multiple baffles 32 are installed in the first flow channel. The multiple baffles 32 are arranged opposite to each other along the first flow channel and at intervals, so that the falling film evaporator has excellent refrigerant distribution capability and can evenly distribute the refrigerant to achieve the purpose of efficient cooling.

[0033] As another embodiment of the present invention, unlike the above embodiments, this embodiment also includes a film distribution assembly 4 connected to the flow equalization assembly 3. The film distribution assembly 4 includes a cavity in which a first liquid distribution plate 43 and a second liquid distribution plate 44 are installed to achieve uniform distribution of refrigerant and effectively enhance the cooling effect of the falling film evaporator.

[0034] In another embodiment of the present invention, unlike the above embodiments, the flow equalization component 3 further includes a second flow channel. The second flow channel is arranged around the periphery of the first flow channel and is connected to the first flow channel and the cavity, respectively. This can effectively reduce the flow rate of the refrigerant, so that the refrigerant can be evenly distributed into the cavity of the film assembly 4.

[0035] In another embodiment of the present invention, unlike the above embodiments, the first flow channel is composed of a side plate 33, a bottom plate 35, and a top cover 37, and the second flow channel is composed of a side plate 33, a side plate 34, a bottom plate 35, and a side cover 38. The side plate 33 includes a first side plate 3301 and a second side plate 3302. The first side plate 3301 and the second side plate 3302 are closely connected to facilitate the reduction of the liquid refrigerant flow rate, so that the refrigerant can flow evenly into the membrane assembly.

[0036] In another embodiment of the present invention, unlike the above embodiment, the top cover 37 is provided with a second opening, and a gas-liquid filter screen 36 is installed on the second opening, so that a small amount of liquid refrigerant mixed with gaseous refrigerant is intercepted and then enters the first flow channel composed of baffles 32, while the gaseous refrigerant is successfully separated out.

[0037] In another embodiment of the present invention, unlike the above embodiments, an anti-impact platform 31 is installed in the first flow channel, so that when the refrigerant fluid moves to the anti-impact platform, it can quickly spread out along the circumference of the anti-impact platform, and the speed is greatly reduced. At the same time, the anti-impact platform has a certain thickness to avoid damage to the components due to excessive impact. The height of the anti-impact platform is greater than the height of the baffle plate, which effectively avoids splashing of liquid refrigerant. Moreover, the sum of the lengths of two adjacent baffle plates, L1+L2, is greater than the length L3 of the second side plate 3302, which effectively reduces the flow rate of liquid refrigerant and ensures uniform distribution of refrigerant.

[0038] In another embodiment of the present invention, unlike the above embodiments, the second side plate 3302, which is arranged opposite to the anti-impact platform, is provided with a first aperture that communicates with the second flow channel, thereby reducing the flow rate of the liquid refrigerant and enabling the refrigerant to flow evenly into the membrane assembly.

[0039] In another embodiment of the present invention, unlike the above embodiments, the side plate 34 is provided with a plurality of through holes that communicate with the fabric assembly 4, so that the refrigerant can flow into the fabric assembly evenly.

[0040] In another embodiment of the present invention, unlike the above embodiments, the cavity is composed of a sealing plate 41 and a frame 42, and the sealing plate 41 has a second opening that matches the flow equalization component 3. The flow equalization component 3 is embedded in the second opening and communicates with the cavity, so that the falling film evaporator can evenly distribute the refrigerant.

[0041] As a further optimization of the present invention, the first liquid distribution plate 43 and the second liquid distribution plate 44 are provided with a plurality of openings, and the openings of the second liquid distribution plate 44 are uniformly arranged along the axial direction directly above each heat exchange tube, so that the liquid refrigerant that has undergone multiple equalization flows will form multiple downward spray flows along the distributed openings and be uniformly distributed on the outer surface of each heat exchange tube, thereby achieving effective heat exchange of the heat exchange tube.

[0042] The working principle of this invention is as follows: Refrigerant fluid (coexisting in gaseous and liquid states) enters the falling film evaporator at high speed through the inlet pipe 1. When it reaches the anti-impact platform 31, the refrigerant fluid rapidly spreads out circumferentially along the platform, significantly reducing its speed. Simultaneously, the anti-impact platform has a certain thickness, preventing damage to components due to excessive impact. At this time, due to the obstruction of the baffle plate 32, the gaseous refrigerant escapes from the notch in the top cover 37. Because a gas-liquid filter screen 36 is installed here, a small amount of liquid refrigerant mixed with the gaseous refrigerant is intercepted and enters the first flow channel formed by the baffle plate 32, while the gaseous refrigerant is successfully separated. Simultaneously, a large amount of liquid refrigerant will flow along the first flow channel formed by the baffle plate 32, undergoing multiple deflections before entering the second flow channel formed by the side plate 33, side plate 34, bottom plate 35, and side cover 38 through the notches at both ends of the side plate 33. In this channel, the liquid refrigerant will enter the film assembly 4 through the openings on the side plate 34.

[0043] When the liquid refrigerant reaches the membrane assembly 4 from the anti-rush flow equalization device 3, its flow velocity has decreased significantly, and its movement has become nearly stable. The first layer of the liquid distribution plate 43 has numerous openings, allowing the liquid refrigerant flowing through it to undergo further equalization before entering the second layer of the liquid distribution plate 44. The second layer of the liquid distribution plate 44 has evenly distributed openings along the axial direction directly above each heat exchange tube. The liquid refrigerant, having undergone multiple equalization processes, forms multiple downward spray streams along these openings, evenly distributing them on the outer surface of each heat exchange tube, thus achieving highly efficient cooling.

[0044] Therefore, the flow equalization and liquid distribution device of the present invention decelerates, equalizes, and separates the refrigerant fluid (coexisting in gaseous and liquid states) that enters at high speed from the liquid inlet pipe 1 through the anti-rush flow equalization component 3; the processed liquid refrigerant enters the lower membrane distribution component 4, and through the combined action of the first liquid distribution plate 43 and the second liquid distribution plate 44, the refrigerant can be dripped evenly onto the outer surface of the heat exchange tube.

[0045] In the description of this invention, it should be understood that the terms "upper", "lower", "bottom", "top", "front", "rear", "inner", "outer", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0046] Although the invention has been described with reference to preferred embodiments, various modifications can be made and components can be replaced with equivalents without departing from the scope of the invention. In particular, the technical features mentioned in the various embodiments can be combined in any manner as long as there is no structural conflict. The invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A liquid distribution and equalization device, characterized in that: The system includes a flow equalization assembly connected to an inlet pipe. The flow equalization assembly includes a first flow channel, in which a plurality of baffles are installed. The plurality of baffles are arranged opposite to each other along the first flow channel and at intervals. It also includes a membrane assembly connected to the flow equalization component, the membrane assembly including a cavity in which a first liquid distribution plate and a second liquid distribution plate are installed; The flow equalization component further includes a second flow channel, which is arranged around the periphery of the first flow channel and is connected to the first flow channel and the cavity, respectively.

2. The liquid distribution device according to claim 1, characterized in that: The first flow channel is composed of a side plate, a bottom plate, and a top cover. The second flow channel is composed of a side plate, a side plate, a bottom plate, and a side cover. The side plate includes a first side plate and a second side plate, and the first side plate and the second side plate are tightly connected.

3. The liquid distribution device according to claim 2, characterized in that: The top cover has a second opening, and a gas-liquid filter screen is installed on the second opening.

4. The liquid distribution device according to claim 2, characterized in that: An anti-impact platform is also installed in the first flow channel, and the height of the anti-impact platform is less than the height of the baffle plate.

5. The liquid distribution device according to claim 4, characterized in that: A first aperture connected to the second flow channel is provided on the second side plate, which is arranged opposite to the anti-impact platform.

6. The liquid distribution device according to claim 4, characterized in that: The sum of the lengths of two adjacent baffles, L1+L2, is greater than the length of the second side plate, L3.

7. The liquid distribution device according to claim 4, characterized in that: The side plate has multiple through holes that communicate with the film assembly.

8. The liquid distribution device according to claim 1, characterized in that: The cavity is composed of a sealing plate and a frame, and the sealing plate has a second opening that matches the flow equalization component. The flow equalization component is embedded in the second opening and communicates with the cavity.

9. The liquid distribution device according to claim 1, characterized in that: The first and second liquid distribution plates have multiple openings.

10. A falling film evaporator, comprising a cylindrical body, wherein a liquid inlet pipe, a gas outlet pipe, and a baffle are installed on the cylindrical body, and a plurality of heat exchange tubes are arranged inside the baffle, characterized in that: It also includes the liquid distribution device according to any one of claims 1-9, wherein the liquid distribution device is installed in the cylinder and is connected to the liquid inlet pipe and the gas outlet pipe, and the heat exchange tube is arranged below the liquid distribution device.

11. The falling film evaporator according to claim 10, characterized in that: The openings of the second layer liquid distribution plate are evenly arranged along the axial direction directly above each heat exchange tube.

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