Heat exchange fin, heat exchange tube and falling film evaporator

Abstract

The invention relates to a heat exchange fin, a heat exchange tube and a falling film evaporator, and the heat exchange fin comprises a base body internally provided with an evaporation cavity; in the flowing direction of the liquid film, the second flow guide part is positioned above the first flow guide part; the second flow guide piece comprises a flow guide groove and a blocking part, the flow guide groove penetrates through the surface of the base body, and a groove opening communicated with the evaporation cavity is formed in the surface of the base body; the blocking part is arranged in the groove opening and divides the flow guide groove into a first groove section, a cavitation section and a second groove section, and the cavitation section is communicated between the first groove section and the second groove section. The heat exchange tube comprises a tube body; the heat exchange fin is provided. The falling film evaporator comprises the heat exchange tube. According to the heat exchange fin, the heat exchange tube and the falling film evaporator, a plurality of vaporization cores can be excited and generated at the same time through the first groove section and the second groove section, and the generated vaporization cores can be temporarily stored in the cavitation section, so that the generation efficiency of steam cores is greatly improved.

Description

Technical Field

[0001] The present application relates to the technical field of heat exchangers, and particularly to a heat exchange fin, a heat exchange tube and a falling film evaporator. Background Art

[0002] As a new type of high-efficiency energy-saving equipment, the horizontal tube falling film evaporator is gradually replacing the flooded evaporator due to its advantages such as small refrigerant charge, small hydrostatic pressure difference, high heat transfer efficiency and convenient oil return. Different from the flooded evaporator, in order to make the liquid film spread evenly on the surface of the heat exchange tube, devices such as a liquid distributor and a liquid equalizing plate are arranged in the liquid film flow direction. If the liquid distribution effect is not ideal, phenomena such as heat transfer deterioration and liquid carry-over in suction will occur in the heat exchanger. In recent years, due to the requirements of energy conservation, environmental protection, cost reduction and efficiency improvement, the design demand for compact falling film evaporators is increasing. However, compared with general falling film evaporators, the liquid refrigerant flow rate of compact ones is smaller, which poses higher requirements for liquid film formation.

[0003] However, in the existing falling film evaporators, there is no fin design that utilizes the liquid film flow law during falling film to enhance boiling heat transfer. The liquid film distribution effect of the falling film evaporator is not ideal, affecting the heat transfer efficiency. Summary of the Invention

[0004] Based on this, in view of the problem of low heat transfer efficiency of the heat exchange fins of the existing falling film evaporators, it is necessary to provide a heat exchange fin, a heat exchange tube and a falling film evaporator.

[0005] A heat exchange fin is used for evaporating a liquid refrigerant to form a liquid film and a gaseous refrigerant. The heat exchange fin includes: a base body with an evaporation cavity provided therein; a first flow guiding member and a second flow guiding member arranged on the same surface of the base body. The first flow guiding member is used for guiding the liquid film, and the second flow guiding member is used for guiding the gaseous refrigerant. In the liquid film flow direction, the second flow guiding member is located above the first flow guiding member, and both the second flow guiding member and the first flow guiding member protrude along the liquid film flow direction. Wherein, the second flow guiding member includes a flow guiding groove and a blocking portion. The flow guiding groove penetrates the surface of the base body and forms a notch communicating with the evaporation cavity on the surface of the base body. The blocking portion is arranged at the notch and divides the flow guiding groove into a first groove section, a gas cavity section and a second groove section. The gas cavity section communicates between the first groove section and the second groove section.

[0006] For the above heat exchange fin, the blocking portion of the second flow guiding member is arranged at the notch of the flow guiding groove and divides the flow guiding groove into a first groove section, a gas cavity section and a second groove section. Multiple vaporization nuclei can be simultaneously excited and generated through the first groove section and the second groove section, and the generated vaporization nuclei can be temporarily stored in the gas cavity section, greatly improving the generation efficiency of vapor nuclei; by using the inertia of the liquid film, the gaseous refrigerant is separated from the liquid film through the first flow guiding member, increasing the separation frequency of the gaseous refrigerant and enhancing the heat transfer efficiency of the transient heat conduction process.

[0007] In one embodiment, in the liquid film flow direction, the first groove section has a first input end and a first output end. The first output end is located below the first input end and is used to output the gaseous refrigerant. The beneficial effect here is that the first output end is located below the first input end. Due to the buoyancy effect, the gaseous refrigerant output from the first output end will escape from bottom to top, while the liquid film flows from top to bottom. The escape direction of the gaseous refrigerant is opposite to the flow direction of the liquid film, which is conducive to the rapid separation of the liquid film and the gaseous refrigerant, increases the detachment frequency of the gaseous refrigerant, and enhances the heat transfer efficiency of the transient heat conduction process.

[0008] In one embodiment, in the liquid film flow direction, the second groove section has a second input end and a second output end. The second output end is located below the second input end and is used to output the gaseous refrigerant. The cavitation section is arranged between the second output end and the first output end. The beneficial effect here is that the second output end is located below the second input end. Due to the buoyancy effect, the gaseous refrigerant output from the second output end will escape from bottom to top, while the liquid film flows from top to bottom. The escape direction of the gaseous refrigerant is opposite to the flow direction of the liquid film, which is conducive to the rapid separation of the liquid film and the gaseous refrigerant; the generated vaporization nuclei will pass over the blocking part and be temporarily stored in the cavitation section. Utilizing the ability of the cavitation section to temporarily store the generated vaporization nuclei greatly improves the generation efficiency of the vapor nuclei.

[0009] In one embodiment, in the liquid film flow direction, the second output end and the first output end are flush with each other. The beneficial effect here is that the second output end and the first output end are flush with each other, and multiple vaporization nuclei can be generated simultaneously at the same height position, greatly improving the generation efficiency of the vapor nuclei at the same height position.

[0010] In one embodiment, the first groove section and / or the second groove section is an arc-shaped groove protruding along the liquid film flow direction. The beneficial effect here is that the first groove section and / or the second groove section is an arc-shaped groove, which is conducive to the smooth inflow of the liquid film into the first groove section and the second groove section, can simultaneously stimulate the generation of multiple vaporization nuclei, and utilizes the ability of the cavitation section to temporarily store the generated vaporization nuclei, greatly improving the generation efficiency of the vapor nuclei.

[0011] In one embodiment, both the first groove section and the second groove section are arc-shaped grooves, and the two arc-shaped grooves are configured as two 1 / 4 arc structures symmetrically distributed with the cavitation section as the center. The beneficial effect here is that multiple vaporization nuclei can be simultaneously stimulated and generated through the first groove section and the second groove section. The first groove section and the second groove section are symmetrically distributed left and right with the cavitation section as the center, which is conducive to the uniformity and efficiency of the distribution of the vaporization nuclei.

[0012] In one embodiment, the first flow guide has two flow diversion ends and a converging end, and the two flow diversion ends are spaced apart; in the flow direction of the liquid film, each flow diversion end is located above the converging end. The beneficial effect here is that the liquid film is diverted into two flows, left and right, by the two flow diversion ends, and the two diverted liquid films flow from top to bottom to converge at the converging end, which prevents the liquid film from shrinking and rupturing, strengthens the spreading of the liquid film on the surface of the heat exchange tube, avoids the formation of dry spots, and reduces the probability of deterioration of bottom heat transfer during falling film evaporation heat exchange.

[0013] In one embodiment, the central axis of the converging end is arranged to coincide with the central axis of the cavitation section. The beneficial effect here is that because the central axis of the converging end is arranged to coincide with the central axis of the cavitation section, under the guidance of the converging end, the bubbles produced by the cavitation section can quickly detach from the surface of the substrate, thereby increasing the detachment frequency of the gaseous refrigerant and enhancing the heat transfer efficiency of the transient heat conduction process.

[0014] In one embodiment, the first flow guide is an arc-shaped boss protruding along the flow direction of the liquid film. The beneficial effect here is that the first flow guide is an arc-shaped boss, and the inertia of the liquid film is utilized to more quickly separate the gaseous refrigerant from the liquid film through the first flow guide, thereby increasing the separation frequency of the gaseous refrigerant and enhancing the heat transfer efficiency of the transient heat conduction process.

[0015] In one embodiment, the arc-shaped boss is constructed as an arc structure symmetrically distributed with the cavitation section as the center. The beneficial effect here is that the arc-shaped boss is constructed to be symmetrically distributed with the cavitation section as the center, which enhances the transient heat conduction when the liquid film infiltrates the arc-shaped boss after the bubble detaches, enhances the boiling heat transfer efficiency, and enhances the spreading of the liquid film on the surface of the heat exchange tube.

[0016] In one embodiment, the center angle of the arc structure is in the range of 45° to 90°. The beneficial effect here is that by limiting the center angle θ of the arc structure to a preset range, not only can the spreading effect of the liquid film be enhanced, but also the speed of the liquid film perpendicular to the surface of the heat exchange tube in the first guide member meets the requirements, so that the separation speed of the bubble in the first guide member is within the preset range.

[0017] In one embodiment, in the flow direction of the liquid film, the arc-shaped boss has an inner side surface located between the two diverter ends and facing the first flow guide, and the inner side surface is constructed as a smooth arc surface structure. The beneficial effect here is that the inner side surface is constructed as a smooth arc surface structure, which can enable the generated bubbles to quickly detach from the inner side surface of the first flow guide, which is conducive to improving the detachment speed of the bubbles in the first flow guide, increasing the detachment frequency of the gaseous refrigerant, and enhancing the heat transfer efficiency of the transient heat conduction process.

[0018] In one embodiment, in the flowing direction of the liquid film, the arc-shaped convex platform has an inner side surface located between the two diversion ends and facing the first diversion member, and the inner side surface is configured as a wavy arc surface structure. The beneficial effect here is that the inner side surface is configured as a wavy arc surface structure, which will increase the friction force when the bubbles pass over the first diversion member, slightly reduce the detachment speed of the bubbles on the first diversion member, strengthen the transient heat conduction when the liquid film infiltrates the arc-shaped convex platform after the bubbles are detached, strengthen the boiling heat transfer efficiency, and strengthen the spreading condition of the liquid film on the surface of the heat exchange tube.

[0019] In one embodiment, the number of the first diversion members is at least two, and each of the first diversion members forms at least two rows. The first diversion members in the same row are spaced apart, and the first diversion members in different rows are staggeredly distributed. The beneficial effect here is that the liquid film is sequentially diverted by each row of the first diversion members, preventing the shrinkage and rupture of the liquid film, strengthening the spreading condition of the liquid film on the surface of the heat exchange tube, avoiding the generation of dry spots, and reducing the probability of bottom heat transfer deterioration during falling film evaporation heat transfer.

[0020] In one embodiment, the blocking portion is integrally formed on the surface of the base body. The beneficial effect here is that the blocking portion and the base body are an integral structure, with good integrity and high mechanical strength.

[0021] A heat exchange tube includes: a tube body; the above-mentioned heat exchange fins provided on the outer surface of the tube body.

[0022] For the above-mentioned heat exchange tube, the blocking portion of the second diversion member of the heat exchange fin is provided at the notch of the diversion groove, and divides the diversion groove into a first groove section, a cavity section and a second groove section. Multiple vaporization nuclei can be simultaneously excited and generated through the first groove section and the second groove section, and the generated vaporization nuclei can be temporarily stored in the cavity section, greatly improving the generation efficiency of the vapor nuclei; by using the inertia of the liquid film, the gaseous refrigerant is separated from the liquid film through the first diversion member, increasing the detachment frequency of the gaseous refrigerant and strengthening the heat transfer efficiency of the transient heat conduction process.

[0023] A falling film evaporator includes the above-mentioned heat exchange tube.

[0024] For the above-mentioned falling film evaporator, the blocking portion of the second diversion member of the heat exchange fin is provided at the notch of the diversion groove, and divides the diversion groove into a first groove section, a cavity section and a second groove section. Multiple vaporization nuclei can be simultaneously excited and generated through the first groove section and the second groove section, and the generated vaporization nuclei can be temporarily stored in the cavity section, greatly improving the generation efficiency of the vapor nuclei; by using the inertia of the liquid film, the gaseous refrigerant is separated from the liquid film through the first diversion member, increasing the detachment frequency of the gaseous refrigerant and strengthening the heat transfer efficiency of the transient heat conduction process. Description of the Drawings

[0025] Figure 1Is an axonometric view of a heat exchange fin in some embodiments of the present application.

[0026] Figure 2 Is Figure 1 A partial enlarged view of the heat exchange fin at position A shown in the figure.

[0027] Figure 3 Is Figure 1 A side view of the heat exchange fin shown in the figure.

[0028] Figure 4 Is Figure 3 A partial enlarged view of the heat exchange fin at position B shown in the figure.

[0029] Figure 5 Is Figure 1 A top view of the heat exchange fin shown in the figure.

[0030] Figure 6 Is Figure 1 A schematic diagram of the central angle of the first flow guiding member in the heat exchange fin shown in the figure.

[0031] Figure 7 Is a side view of a heat exchange fin in some other embodiments of the present application.

[0032] Figure 8 Is Figure 7 A top view of the heat exchange fin shown in the figure.

[0033] Reference numerals:

[0034] 100, matrix; 101, evaporation cavity;

[0035] 200, first flow guiding member; 210, shunt end; 220, confluence end; 230, inner side;

[0036] 300, second flow guiding member; 310, flow guiding groove; 310a, notch; 311, first groove section; 311a, first input end; 311b, first output end; 312, cavitation section; 313, second groove section; 313a, second input end; 313b, second output end;

[0037] 320, blocking portion. Detailed embodiments

[0038] To make the above objects, features, and advantages of the present application more apparent and understandable, the following describes the detailed embodiments of the present application with reference to the accompanying drawings. Many specific details are set forth in the following description to fully understand the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.

[0039] In the description of the present application, it should be understood that the orientation or positional relationship indicated by terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present application.

[0040] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present application, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0041] In the present application, unless otherwise clearly specified and limited, terms such as "initial", "connected", "connected to", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0042] In the present application, unless otherwise clearly specified and limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0043] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are only for illustrative purposes and do not represent the only implementation.

[0044] Please refer to Figures 1 to 4 , in one embodiment, the heat exchange fin is used to evaporate the liquid refrigerant and form a liquid film and a gaseous refrigerant. The heat exchange fin includes a base body 100, a first flow guide member 200 and a second flow guide member 300. An evaporation chamber 101 is provided in the base body 100. The first flow guide member 200 and the second flow guide member 300 are disposed on the same surface of the base body 100. The first flow guide member 200 is used to guide the liquid film, and the second flow guide member 300 is used to guide the gaseous refrigerant; in the liquid film flow direction, the second flow guide member 300 is located above the first flow guide member 200.

[0045] Among them, the second flow guide member 300 includes a flow guide groove 310 and a blocking portion 320. The flow guide groove 310 penetrates the surface of the base body 100 and forms a notch 310a communicating with the evaporation chamber 101 on the surface of the base body 100; the blocking portion 320 is disposed at the notch 310a and divides the flow guide groove 310 into a first groove section 311, a cavity section 312 and a second groove section 313. The cavity section 312 communicates between the first groove section 311 and the second groove section 313.

[0046] It should be noted that the first groove section 311, the cavity section 312 and the second groove section 313 are arranged in sequence from left to right. The first groove section 311 and the second groove section 313 are connected through the cavity section 312. Both the first groove section 311 and the second groove section 313 communicate with the outside, and the cavity section 312 does not communicate with the outside.

[0047] Here, the liquid refrigerant is sprayed onto the outer surface of the heat exchange fin from top to bottom. The liquid refrigerant flows axially and circumferentially on the outer surface of the heat exchange fin and forms a liquid film on the surface of the base body 100. Due to the continuous heating of the evaporation chamber 101, the liquid film is evaporated and vaporized to form a gaseous refrigerant during the flow. When the liquid film flows along Figures 3 to 4When flowing in the Z direction as shown, the liquid film impacts the first flow guide member 200. Part of the liquid film is split into two flows, left and right, by the first flow guide member 200, and the other part of the liquid film enters the first groove section 311 and the second groove section 313 to generate vaporization nuclei. The generated vaporization nuclei will pass by the blocking portion 320 and be temporarily stored in the cavitation section 312. The vaporization nuclei stored in the cavitation section 312 generate bubbles (i.e., gaseous refrigerant) after being heated. Since the impact of the liquid film on the first flow guide member 200 generates a velocity component perpendicular to the surface of the substrate 100, the generated bubbles can quickly detach from the surface of the substrate 100.

[0048] For the heat exchange fin described above, the blocking portion 320 of the second flow guide member 300 is provided at the notch 310a of the flow guide groove 310 and divides the flow guide groove 310 into a first groove section 311, a cavitation section 312, and a second groove section 313. Multiple vaporization nuclei can be simultaneously excited and generated through the first groove section 311 and the second groove section 313, and the generated vaporization nuclei can be temporarily stored in the cavitation section 312, greatly improving the generation efficiency of vapor nuclei; by using the inertia of the liquid film, the gaseous refrigerant is separated from the liquid film through the first flow guide member 200, increasing the detachment frequency of the gaseous refrigerant and enhancing the heat transfer efficiency of the transient heat conduction process.

[0049] In an embodiment of the present application, the substrate 100 is a member having an evaporation cavity 101, and the substrate 100 can adopt various structural forms. For example, the substrate 100 is a hollow tubular structure, and the tubular structure can be a round tube, a square tube, or other shapes. The shape of the substrate 100 is not limited herein.

[0050] In an embodiment of the present application, the first flow guide member 200 is a member for guiding the liquid film, and the first flow guide member 200 can adopt various structural forms. For example, the first flow guide member 200 is a convex platform protruding from the surface of the substrate 100 to facilitate guiding and distributing the liquid film.

[0051] In an embodiment of the present application, the second flow guide member 300 is a member for guiding the gaseous refrigerant, and the second flow guide member 300 can adopt various structural forms. For example, the second flow guide member 300 includes a flow guide groove 310 and a blocking portion 320. The flow guide groove 310 is a groove provided on the surface of the substrate 100, and the blocking portion 320 is integrally formed on the surface of the substrate 100. The blocking portion 320 divides the flow guide groove 310 into a first groove section 311, a cavitation section 312, and a second groove section 313. Multiple vaporization nuclei can be simultaneously excited and generated through the first groove section 311 and the second groove section 313, and the generated vaporization nuclei can be temporarily stored in the cavitation section 312.

[0052] Specifically, please refer to Figure 5 , in the liquid film flow direction, the first groove section 311 has a first input end 311a and a first output end 311b, and the first output end 311b is located below the first input end 311a and is used to output the gaseous refrigerant.

[0053] It can be understood that when the liquid film flows from top to bottom (i.e., along the Figure 5 Z direction shown), the liquid film can enter the first groove section 311 from the first input end 311a, be evaporated in the first groove section 311 to generate vaporization nuclei, the generated vaporization nuclei will pass by the blocking portion 320 and be temporarily stored in the cavity section 312, and the vaporization nuclei stored in the cavity will generate bubbles after being heated, and the bubbles are output to the outside of the first groove section 311 through the first output end 311b.

[0054] The beneficial effect here is that the first output end 311b is located below the first input end 311a. Due to the buoyancy effect, the gaseous refrigerant output from the first output end 311b will escape from bottom to top, while the liquid film flows from top to bottom. The escape direction of the gaseous refrigerant is opposite to the flow direction of the liquid film, which is beneficial to the rapid separation of the liquid film from the gaseous refrigerant, increases the separation frequency of the gaseous refrigerant, and enhances the heat transfer efficiency of the transient heat conduction process.

[0055] In the embodiment of the present application, the number of the first input end 311a and the first output end 311b is not limited to one, that is, the number of the first input end 311a and the first output end 311b can both be at least two, and the number of the first input end 311a and the first output end 311b is not limited here.

[0056] More specifically, please refer to Figure 5 , in the liquid film flow direction, the second groove section 313 has a second input end 313a and a second output end 313b. The second output end 313b is located below the second input end 313a and is used to output the gaseous refrigerant. The cavity section 312 is arranged between the second output end 313b and the first output end 311b.

[0057] It can be understood that when the liquid film flows from top to bottom (i.e., along the Figure 5 Z direction shown), the liquid film can enter the second groove section 313 from the second input end 313a, be evaporated in the second groove section 313 to generate vaporization nuclei, the generated vaporization nuclei will pass by the blocking portion 320 and be temporarily stored in the cavity section 312, and the vaporization nuclei stored in the cavity section 312 will generate bubbles after being heated, and the bubbles are output to the outside of the second groove section 313 through the second output end 313b.

[0058] The beneficial effects here are as follows: The second output end 313b is located below the second input end 313a. Due to the buoyancy effect, the gaseous refrigerant output from the second output end 313b will escape from bottom to top, while the liquid film flows from top to bottom. The escape direction of the gaseous refrigerant is opposite to the flow direction of the liquid film, which is conducive to the rapid separation of the liquid film and the gaseous refrigerant; the generated vaporization nuclei will pass over the blocking portion 320 and be temporarily stored in the cavitation section 312. By using the cavitation section 312 to temporarily store the generated vaporization nuclei, the generation efficiency of the vapor nuclei is greatly improved.

[0059] In the embodiments of the present application, the number of the second input end 313a and the second output end 313b is not limited to one, that is, the number of the second input end 313a and the second output end 313b can both be at least two, and the number of the second input end 313a and the second output end 313b is not limited here.

[0060] In the embodiments of the present application, the cavitation section 312 is arranged between the second output end 313b and the first output end 311b. The cavitation section 312 can be arc-shaped or linear, and the shape of the cavitation section 312 is not limited here.

[0061] Specifically in this embodiment, please refer to Figure 5 , in the liquid film flow direction, the second output end 313b and the first output end 311b are flush.

[0062] It should be noted that the second output end 313b and the first output end 311b are flush, that is: along the Figure 5 shown Z direction, the height positions of the second output end 313b and the first output end 311b are the same.

[0063] The beneficial effects here are as follows: The second output end 313b and the first output end 311b are flush, and multiple vaporization nuclei can be generated simultaneously at the same height position, greatly improving the vapor nucleus generation efficiency at the same height position.

[0064] In the embodiments of the present application, in the liquid film flow direction, the second input end 313a and the first input end 311a can be flush or not flush.

[0065] Please refer to Figure 5 , the first groove section 311 and / or the second groove section 313 are arc-shaped grooves protruding along the liquid film flow direction.

[0066] It can be understood that part of the liquid film enters the first groove section 311 and the second groove section 313 to generate vaporization nuclei. The generated vaporization nuclei will pass over the blocking portion 320 and be temporarily stored in the cavitation section 312. The vaporization nuclei stored in the cavitation section 312 generate bubbles (i.e., gaseous refrigerant) after being heated.

[0067] The beneficial effects here are as follows: The first groove section 311 and / or the second groove section 313 are arc-shaped grooves, which facilitate the smooth inflow of the liquid film into the first groove section 311 and the second groove section 313, can simultaneously stimulate the generation of multiple vaporization nuclei, and utilize the vaporization nuclei generated temporarily in the cavitation section 312, greatly improving the generation efficiency of the vapor nuclei.

[0068] In the embodiments of the present application, both the first groove section 311 and the second groove section 313 can be set as arc-shaped grooves, or one of them can be set as an arc-shaped groove. Among them, the arc-shaped groove can be a single circular arc groove, a multi-arc combined groove or a parabolic arc groove.

[0069] Specifically, please refer to Figure 5 , both the first groove section 311 and the second groove section 313 are arc-shaped grooves, and the two arc-shaped grooves are configured as two 1 / 4 arc structures symmetrically distributed with the cavitation section 312 as the center.

[0070] It should be noted that along the Figure 5 shown Z direction, the first groove section 311 and the second groove section 313 are symmetrically distributed left and right with the cavitation section 312 as the center, and both the first groove section 311 and the second groove section 313 are 1 / 4 arc structures.

[0071] The beneficial effects here are as follows: Multiple vaporization nuclei can be simultaneously stimulated and generated through the first groove section 311 and the second groove section 313. The first groove section 311 and the second groove section 313 are symmetrically distributed left and right with the cavitation section 312 as the center, which is beneficial to the uniformity and efficiency of the distribution of the vaporization nuclei.

[0072] Please refer to Figure 5 , the first flow guiding member 200 has two shunt ends 210 and a converging end 220, and the two shunt ends 210 are spaced apart; in the liquid film flow direction, each shunt end 210 is located above the converging end 220.

[0073] It can be understood that since the first flow guiding member 200 has two shunt ends 210 located above the converging end 220, when the liquid film flows along the Figure 5 shown Z direction, the liquid film will first impact the two shunt ends 210 of the first flow guiding member 200, and part of the liquid film is shunted into two left and right flows by the two shunt ends 210, and the two shunted liquid films flow from top to bottom to the converging end 220 to converge.

[0074] The beneficial effects here are as follows: The liquid film is shunted into two left and right flows by the two shunt ends 210, and the two shunted liquid films flow from top to bottom to the converging end 220 to converge, preventing the shrinkage and rupture of the liquid film, strengthening the spreading of the liquid film on the surface of the heat exchange tube, avoiding the generation of dry spots, and reducing the probability of deterioration of bottom heat transfer during falling film evaporation heat transfer.

[0075] In the embodiments of the present application, the two shunt ends 210 are along theFigure 5 are spaced apart in the X direction as shown, and at Figure 5 the top sides of the two flow splitting ends 210 in the Z direction shown are flush, so as to facilitate uniform flow splitting of the liquid film.

[0076] In an embodiment of the present application, the two flow splitting ends 210 are at Figure 5 above the confluence end 220 in the Z direction shown, and the confluence end 220 is along Figure 5 in the middle position of the two flow splitting ends 210 in the X direction shown, so as to facilitate uniform flow splitting and confluence of the liquid film.

[0077] Furthermore, please refer to Figure 5 , the central axis of the confluence end 220 is set to coincide with the central axis of the cavitation section 312.

[0078] It can be understood that when the liquid film flows from top to bottom in the Figure 5 Z direction shown, the vaporization nuclei stored in the cavitation section 312 generate bubbles (i.e., gaseous refrigerant) after being heated. The liquid film impacting the first flow guiding member 200 will generate a velocity component perpendicular to the surface of the substrate 100. Under the guiding action of the confluence end 220, the generated bubbles can quickly detach from the surface of the substrate 100.

[0079] The beneficial effect here is that since the central axis of the confluence end 220 coincides with the central axis of the cavitation section 312, under the guiding action of the confluence end 220, the bubbles produced by the cavitation section 312 can quickly detach from the surface of the substrate 100, increasing the detachment frequency of the gaseous refrigerant and enhancing the heat transfer efficiency of the transient heat conduction process.

[0080] In an embodiment of the present application, the confluence end 220 is also the bottom of the first flow guiding member 200, and the cavitation section 312 is also the bottom of the second flow guiding member 300. The central axis of the confluence end 220 coincides with the central axis of the cavitation section 312, that is: the central axis of the bottom of the first flow guiding member 200 coincides with the central axis of the bottom of the second flow guiding member 300.

[0081] Please refer to Figure 5 , the first flow guiding member 200 is an arc-shaped convex platform protruding along the liquid film flow direction.

[0082] It should be noted that when the liquid film is along Figure 5When flowing in the Z direction as shown, the liquid film impacts the first flow guide member 200. Part of the liquid film is split by the first flow guide member 200 into two flows, left and right, and another part of the liquid film enters the first groove section 311 and the second groove section 313 and generates vaporization nuclei. The generated vaporization nuclei will pass by the blocking portion 320 and be temporarily stored in the cavitation section 312. The vaporization nuclei stored in the cavitation section 312 generate bubbles (i.e., gaseous refrigerant) after being heated. Since the impact of the liquid film on the first flow guide member 200 generates a velocity component perpendicular to the surface of the substrate 100, the generated bubbles can quickly detach from the surface of the substrate 100.

[0083] The beneficial effect here is that the first flow guide member 200 is an arc-shaped convex platform. Utilizing the inertia of the liquid film, the gaseous refrigerant can be separated from the liquid film more quickly through the first flow guide member 200, increasing the detachment frequency of the gaseous refrigerant and enhancing the heat transfer efficiency of the transient heat conduction process.

[0084] In the embodiment of the present application, the first flow guide member 200 and the substrate 100 can be an integral structure. For example, the first flow guide member 200 and the substrate 100 are integrally formed by injection molding, casting, etc., with good integrity and high mechanical strength. Or, the first flow guide member 200 and the substrate 100 can also be a split structure. For example, the first flow guide member 200 and the substrate 100 are fixed by plugging, clamping, etc.

[0085] Furthermore, please refer to Figure 5 , and the arc-shaped convex platform is configured as an arc structure symmetrically distributed with the cavitation section 312 as the center.

[0086] It should be noted that along the Figure 5 shown Z direction, the arc-shaped convex platform is symmetrically distributed left and right with the cavitation section 312 as the center, and the arc-shaped convex platform as a whole is an arc structure.

[0087] The beneficial effect here is that the arc-shaped convex platform is configured to be symmetrically distributed with the cavitation section 312 as the center, strengthening the transient heat conduction when the liquid film wets the arc-shaped convex platform after the bubbles detach, enhancing the boiling heat transfer efficiency, and strengthening the spreading of the liquid film on the surface of the heat exchange tube.

[0088] Even further, please refer to Figure 6 , and the central angle range of the arc structure is 45° - 90°.

[0089] It should be noted that the central angle of the arc structure is θ. The smaller the central angle θ of the arc structure, the smaller the radian of the arc structure, which can increase the flow rate of the liquid film split left and right when flowing through the first flow guide member 200, strengthening the spreading effect on the liquid film. However, the velocity of the liquid film perpendicular to the surface of the heat exchange tube at the first flow guide member 200 decreases, reducing the detachment velocity of the bubbles at the first flow guide member 200.

[0090] The beneficial effects here are as follows: By limiting the central angle θ of the arc structure within a preset range, not only can the spreading effect of the liquid film be strengthened, but also the velocity of the liquid film perpendicular to the surface of the heat exchange tube in the first flow guide 200 meets the requirements, so that the detachment velocity of the bubbles at the first flow guide 200 is within the preset range.

[0091] Specifically in some embodiments, please refer to Figure 6 , in the liquid film flow direction, the arc-shaped boss has an inner side surface 230 that is located between the two diversion ends 210 and faces the first flow guide 200, and the inner side surface 230 is configured as a smooth arc surface structure.

[0092] It can be understood that when the liquid film flows from top to bottom along the Figure 6 Z direction shown, the vaporization nuclei stored in the cavitation section 312 generate bubbles (i.e., gaseous refrigerant) after being heated. When the liquid film impacts the first flow guide 200, a velocity component perpendicular to the surface of the substrate 100 will be generated. Under the guiding action of the inner side surface 230, the generated bubbles can quickly detach from the surface of the substrate 100.

[0093] The beneficial effects here are as follows: The inner side surface 230 is configured as a smooth arc surface structure, which enables the generated bubbles to quickly detach from the inner side surface 230 of the first flow guide 200, facilitating the increase of the detachment velocity of the bubbles at the first flow guide 200, increasing the detachment frequency of the gaseous refrigerant, and strengthening the heat transfer efficiency of the transient heat conduction process.

[0094] In the embodiments of the present application, the inner side surface 230 is configured as a smooth arc surface structure, that is, the surface of the inner side surface 230 is overall smooth and there are no structures such as folded edges and sharp edges.

[0095] Specifically in some other embodiments, please refer to Figure 7 and Figure 8 , in the liquid film flow direction, the arc-shaped boss has an inner side surface 230 that is located between the two diversion ends 210 and faces the first flow guide 200, and the inner side surface 230 is configured as a wavy arc surface structure.

[0096] The beneficial effects here are as follows: The inner side surface 230 is configured as a wavy arc surface structure. When the bubbles pass over the first flow guide 200, the frictional force will be increased, slightly reducing the detachment velocity of the bubbles at the first flow guide 200, strengthening the transient heat conduction when the liquid film wets the arc-shaped boss after the bubbles detach, strengthening the boiling heat transfer efficiency, and strengthening the spreading condition of the liquid film on the surface of the heat exchange tube.

[0097] In the embodiments of the present application, the inner side surface 230 is configured as a wavy arc surface structure, that is, the surface of the inner side surface 230 is overall provided with structures such as folded edges and sharp edges.

[0098] Please refer to Figure 6, the number of the first flow guiding members 200 is at least two, and each of the first flow guiding members 200 forms at least two rows. The first flow guiding members 200 in the same row are distributed at intervals, and the first flow guiding members 200 in different rows are staggeredly distributed.

[0099] It should be noted that since the first flow guiding member 200 has two flow splitting ends 210 above the confluence end 220, when the liquid film flows along the Figure 6 Z direction shown, the liquid film will first impact the two flow splitting ends 210 of each first flow guiding member 200 in the first row. Part of the liquid film is split into two left and right flows by the two flow splitting ends 210 of each first flow guiding member 200 in the first row. The two split liquid films flow from top to bottom to the confluence end 220 of each first flow guiding member 200 in the first row to converge, and then are split into two left and right flows by the two flow splitting ends 210 of each first flow guiding member 200 in the second row, and then continue to flow from top to bottom to the confluence end 220 of each first flow guiding member 200 in the second row to converge. In this way, the liquid film is sequentially split by each first flow splitting member row by row.

[0100] The beneficial effect here is that the liquid film is sequentially split by each first flow splitting member row by row, preventing the shrinkage and rupture of the liquid film, strengthening the spreading of the liquid film on the surface of the heat exchange tube, avoiding the generation of dry spots, and reducing the probability of deterioration of heat transfer at the bottom during falling film evaporation heat transfer.

[0101] In the embodiment of the present application, the sizes and shapes of all the first flow guiding members 200 are the same to facilitate the uniform distribution of the liquid film. For example, all the first flow guiding members 200 are in the shape of a horseshoe with the same size.

[0102] Please refer to Figure 6 , the blocking portion 320 is integrally formed on the surface of the base body 100.

[0103] The beneficial effect here is that the blocking portion 320 and the base body 100 are of an integral structure, with good integrity and high mechanical strength.

[0104] In the embodiment of the present application, the blocking portion 320 and the base body 100 are of an integral structure. The blocking portion 320 and the base body 100 can be integrally formed by injection molding, casting, etc. The specific method of integrally forming the blocking portion 320 is not limited here.

[0105] Please refer to Figure 1 , the heat exchange tube in one embodiment includes a tube body and the above-mentioned heat exchange fins, and the heat exchange fins are arranged on the outer surface of the tube body.

[0106] For the above heat exchange tubes, the blocking portion 320 of the second flow guiding member 300 of the heat exchange fins is provided at the notch 310a of the flow guiding groove 310, and the flow guiding groove 310 is separated into a first groove section 311, a cavitation section 312 and a second groove section 313. Multiple vaporization nuclei can be simultaneously excited and generated through the first groove section 311 and the second groove section 313, and the generated vaporization nuclei can be temporarily stored in the cavitation section 312, greatly improving the generation efficiency of the vapor nuclei; by utilizing the liquid film inertia, the gaseous refrigerant is separated from the liquid film through the first flow guiding member 200, increasing the separation frequency of the gaseous refrigerant and enhancing the heat transfer efficiency of the transient heat conduction process.

[0107] In an embodiment of the present application, the heat exchange fins are provided on the outer surface of the tube body. The heat exchange fins and the tube body can be an integral structure, for example, integrally formed by injection molding, casting, etc., with good integrity and high mechanical strength; or, the heat exchange fins and the tube body can also be a split structure, for example, the heat exchange fins and the tube body are fixed by clamping, riveting, etc.

[0108] Please refer to Figure 1 , a falling film evaporator in an embodiment includes the above heat exchange tubes.

[0109] It should be noted that, in addition to including the above heat exchange tubes, the falling film evaporator also includes other components such as a liquid distributor and a flow equalizer.

[0110] For the above falling film evaporator, the blocking portion 320 of the second flow guiding member 300 of the heat exchange fins is provided at the notch 310a of the flow guiding groove 310, and the flow guiding groove 310 is separated into a first groove section 311, a cavitation section 312 and a second groove section 313. Multiple vaporization nuclei can be simultaneously excited and generated through the first groove section 311 and the second groove section 313, and the generated vaporization nuclei can be temporarily stored in the cavitation section 312, greatly improving the generation efficiency of the vapor nuclei; by utilizing the liquid film inertia, the gaseous refrigerant is separated from the liquid film through the first flow guiding member 200, increasing the separation frequency of the gaseous refrigerant and enhancing the heat transfer efficiency of the transient heat conduction process.

[0111] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0112] The above-described embodiments only represent several implementation manners of the present application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several deformations and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.

Claims

1. A heat exchange fin for evaporating liquid refrigerant and forming a liquid film and a gaseous refrigerant, characterized in that: The heat exchange fins include: A base body (100) having an evaporation chamber (101) therein; A first flow guide (200) and a second flow guide (300) are arranged on the same surface of the base (100), the first flow guide (200) being used to guide the liquid film, and the second flow guide (300) being used to guide the gaseous refrigerant; in the flow direction of the liquid film, the second flow guide (300) is located above the first flow guide (200); The second flow guide member (300) comprises a flow guide groove (310) and a blocking portion (320); the flow guide groove (310) penetrates the surface of the substrate (100) and forms a notch (310a) on the surface of the substrate (100) that is in communication with the evaporation chamber (101); the blocking portion (320) is arranged at the notch (310a) and divides the flow guide groove (310) into a first groove section (311), a cavitation section (312) and a second groove section (313); the cavitation section (312) is in communication with the first groove section (311) and the second groove section (313).

2. The heat exchange fin according to claim 1, characterized in that: In the flow direction of the liquid film, the first slot section (311) has a first input end (311a) and a first output end (311b); the first output end (311b) is located below the first input end (311a) and is used to output the gaseous refrigerant.

3. The heat exchange fin according to claim 2, characterized in that: In the flow direction of the liquid film, the second slot section (313) has a second input end (313a) and a second output end (313b), the second output end (313b) is located below the second input end (313a) and is used to output the gaseous refrigerant, and the cavitation section (312) is arranged between the second output end (313b) and the first output end (311b).

4. The heat exchange fin according to claim 3, characterized in that: In the flow direction of the liquid film, the second output end (313b) and the first output end (311b) are arranged flush with each other.

5. The heat exchange fin according to claim 1, characterized in that: The first groove section (311) and / or the second groove section (313) are arc-shaped grooves protruding along the flow direction of the liquid film.

6. The heat exchange fin according to claim 5, characterized in that: The first slot section (311) and the second slot section (313) are both arc-shaped slots, and the two arc-shaped slots are constructed as two 1 / 4 arc structures symmetrically distributed with the cavitation section (312) as the centre.

7. The heat exchange fin according to claim 1, characterized in that: The first flow guide (200) has two flow-dividing ends (210) and a merging end (220), and the two flow-dividing ends (210) are spaced apart from each other; in the flow direction of the liquid film, each flow-dividing end (210) is located above the merging end (220).

8. The heat exchange fin according to claim 7, characterized in that: The central axis of the converging end (220) is arranged to coincide with the central axis of the cavitation section (312).

9. The heat exchange fin according to claim 7, characterized in that: The first flow guide (200) is an arc-shaped boss protruding along the flow direction of the liquid film.

10. The heat exchange fin according to claim 9, characterized in that: The arc-shaped boss is constructed as an arc structure symmetrically distributed with the cavitation section (312) as the center.

11. The heat exchange fin according to claim 10, characterized in that: The center angle of the arc structure ranges from 45° to 90°.

12. The heat exchange fin according to claim 9, characterized in that: In the flow direction of the liquid film, the arc-shaped boss has an inner side surface (230) located between the two flow-dividing ends (210) and facing the first flow-guiding member (200), and the inner side surface (230) is constructed as a smooth arc surface structure.

13. The heat exchange fin according to claim 9, characterized in that: In the flow direction of the liquid film, the arc-shaped boss has an inner side surface (230) located between the two flow-dividing ends (210) and facing the first flow-guiding member (200), and the inner side surface (230) is constructed as a wave arc surface structure.

14. The heat exchange fin according to claim 1, characterized in that: The number of the first flow guide members (200) is at least two, and the first flow guide members (200) form at least two rows, the first flow guide members (200) located in the same row are arranged at intervals, and the first flow guide members (200) located in different rows are arranged in a staggered manner.

15. The heat exchange fin according to claim 1, characterized in that: The blocking portion (320) is integrally formed on the surface of the base (100).

16. A heat exchange tube, characterized in that: include: tube body; The heat exchange fin according to any one of claims 1 to 15 is arranged on the outer surface of the tube body.

17. A falling film evaporator, characterized in that: Comprising the heat exchange tube as claimed in claim 16.

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