A dual-layer countercurrent flow channel functional heat exchange module and heat exchanger

Abstract

This invention belongs to the field of heat exchanger technology, specifically relating to a double-layered counter-current flow channel functional heat exchange module and heat exchanger. The heat exchange medium flow channels of this invention are arranged in a sequentially stacked structure of a first main flow channel, a first auxiliary flow channel, a second auxiliary flow channel, and a second main flow channel. The first main flow channel and the first auxiliary flow channel are interconnected to form an upper heat source cavity, and the second main flow channel and the second auxiliary flow channel are interconnected to form a lower heat source cavity. Within the same heat source cavity layer, the flow area of ​​the main flow channel is larger than that of the auxiliary flow channel, and the main flow channel and the auxiliary flow channel intersect each other, so that the intersection points form interconnected points. Along the stacking direction of the flow channels, the second auxiliary flow channel is adjacent to the first main flow channel, and the second main flow channel is adjacent to the first auxiliary flow channel, with a gap between the upper heat source cavity and the lower heat source cavity. This invention ensures the self-cleaning function of the icing area through the combined action of "mixed ice melting" and "heat exchange ice melting".

Description

Technical Field

[0001] This invention belongs to the field of heat exchanger technology, specifically relating to a double-layer countercurrent flow channel functional heat exchange module and heat exchanger. Background Technology

[0002] LNG-powered ships utilize a fuel gas supply system (FGSS) to pressurize LNG via pumps, vaporize it in a high-pressure vaporizer, and then transport it to the power system as fuel. The high-pressure vaporizer is a key component of the FGSS system. Because the vaporizer operates in harsh environments with high pressure (above 30 MPa) and low temperature (-162°C), traditional shell-and-tube heat exchangers are bulky, heavy, and have thick walls. The 100°C temperature difference between the hot and cold fluids easily leads to stress and mechanical fatigue, limiting their application in LNG ships. Conventional brazed plate, plate-fin, and frame plate heat exchangers are also difficult to use under high pressure. Currently, diffusion-welded heat exchangers are more commonly used.

[0003] Currently, for the application of high-pressure liquefied natural gas (LNG) vaporization sections in FGSS systems for dual-fuel powered ships, diffusion-welded microchannel heat exchangers still face two challenges: Firstly, the temperature of LNG, the working medium, is extremely low, around -162°C, while the freezing point of heat exchange media such as ethylene glycol aqueous solutions is typically around -40°C. Since the temperature of cryogenic LNG is far lower than the freezing point of ethylene glycol aqueous solutions, the ethylene glycol aqueous solution side is prone to icing in many vaporizers. Once the heat exchange channels on the ethylene glycol aqueous solution side partially freeze, it gradually blocks heat exchange and flow, accelerating the icing rate until the ethylene glycol aqueous solution channels within the vaporizer are completely frozen, causing vaporization failure and affecting the normal operation of the system. Simply increasing the channel diameter to avoid icing is limited by chemical etching, machining processes, and manufacturing economics, and the current etching depth is difficult to exceed 2mm, resulting in very limited practical effectiveness. On the other hand, after prolonged use, the inner walls of the microchannels containing the heat exchange medium accumulate a large amount of impurities, dirt, and oil, which can clog the channels. Furthermore, due to the continuity and closed nature of the channels in conventional diffusion-welded microchannel heat exchangers, this can lead to deterioration of heat exchange or even complete failure, causing system shutdown. Moreover, offshore platforms or gas-powered vessels often lack effective online cleaning equipment and capabilities. Therefore, this issue urgently needs to be addressed. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a double-layered, counter-current flow channel functional heat exchange module. As an internal heat exchange component of the heat exchanger, it can utilize the temperature difference effect generated by the distance difference between the main and auxiliary channels at the working medium flow channel and the heat exchange medium flow channel, as well as the wall heat exchange and fusion heat exchange effects between the main and auxiliary channels, to ensure the suppression of ice growth rate and continuous ice melting function at the ice-covered areas of the main and even auxiliary channels through the combined action of "mixed ice melting" and "heat exchange ice melting". Without affecting the normal operation of the vaporizer, it can ensure the self-cleaning function of the ice-covered areas.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A dual-layer anisotropic flow channel functional heat exchange module includes a heat exchange plate and flow channels within the heat exchange plate for the passage of working medium and heat exchange medium. The flow channels include a first working medium flow channel constituting a first cold source, a heat exchange medium flow channel constituting a heat source, and a second working medium flow channel constituting a second cold source. The heat exchange medium flow channels are arranged in a sequentially stacked structure of a first main flow channel, a first auxiliary flow channel, a second auxiliary flow channel, and a second main flow channel. The first main flow channel and the first auxiliary flow channel are interconnected to form an upper heat source cavity, and the second main flow channel and the second auxiliary flow channel are interconnected to form a lower heat source cavity. Within the same heat source cavity, the flow area of ​​the main flow channel is larger than that of the auxiliary flow channel, and the main flow channel and the auxiliary flow channel intersect each other, such that the intersection points form interconnected connection points. Along the stacking direction of the flow channels, the second auxiliary flow channel is adjacent to the first main flow channel, and the second main flow channel is adjacent to the first auxiliary flow channel, and there is a gap between the upper heat source cavity and the lower heat source cavity.

[0007] Preferably, in a top-view projection, the second auxiliary channel is located within the projection range of the first main channel, and the second main channel is located within the projection range of the first auxiliary channel.

[0008] Preferably, the upper heat source cavity and the lower heat source cavity are formed by three heat exchange plates; a grooved first main flow channel is provided on the lower surface of the first heat exchange plate, a grooved first auxiliary flow channel is provided on the upper surface of the second heat exchange plate, a grooved second auxiliary flow channel is provided on the lower surface of the second heat exchange plate, and a grooved second main flow channel is provided on the upper surface of the third heat exchange plate; the corresponding main flow channel and auxiliary flow channel are slotted together at the connection point to form the corresponding heat source cavity; an upper heat exchange plate with a first working medium flow channel is arranged above the first heat exchange plate, and a lower heat exchange plate with a second working medium flow channel is arranged below the third heat exchange plate.

[0009] Preferably, the upper heat source cavity and the lower heat source cavity are formed by three heat exchange plates. The lower surface of the first heat exchange plate is etched with a grooved first main flow channel, the upper surface of the second heat exchange plate is etched with a grooved first auxiliary flow channel, the lower surface of the second heat exchange plate is etched with a grooved second auxiliary flow channel, and the upper surface of the third heat exchange plate is etched with a grooved second main flow channel. The corresponding main flow channel and auxiliary flow channel are slotted together at the connection point to form the corresponding heat source cavity. A side heat exchange plate that has both a low-pressure LNG flow channel and a high-pressure LNG flow channel is also arranged above or below the first heat exchange plate.

[0010] Preferably, each auxiliary flow channel is formed by combining two or more independent flow channels side by side; each independent flow channel is independently connected to the corresponding main flow channel of the same heat source cavity at the connection point.

[0011] Preferably, the two adjacent intersections of the main flow channel and the auxiliary flow channel in the same heat source cavity are taken as the two endpoints. A section of the auxiliary flow channel between the two endpoints forms a single flow channel segment, and a partition is arranged in the single flow channel segment. The partition extends along the length of the single flow channel segment, thereby dividing the flow channel cavity of the single flow channel segment into two or more isolation cavities. There is a distance between both ends of the partition and the two endpoints.

[0012] Preferably, each main channel and each auxiliary channel has a V-shaped, W-shaped or wavy shape, and in the same heat source cavity, the openings of the main channel and auxiliary channel that cooperate with each other are opposite to each other, so that the openings of the main channel and auxiliary channel are matched to form a closed loop structure, and the connection point is provided at the matching point of the closed loop structure.

[0013] Preferably, the turning points of the V-shaped or W-shaped main flow channel and auxiliary flow channel, or the peaks or troughs of the wavy main flow channel and auxiliary flow channel are used as the inflection points of each flow channel. Then, the main flow channels and auxiliary flow channels that cooperate with each other in the same heat source cavity form a row of flow channel units. The adjacent inflection points of the current row of flow channel units are connected to the next row of flow channel units in the same heat source cavity.

[0014] Preferably, the angle formed between each main flow channel and auxiliary flow channel and the length direction of each heat exchange plate is in the range of (0°, 15°).

[0015] Preferably, an upper arc groove is etched on the surface of the upper heat exchange plate, and the upper arc groove cavity cooperates with the adjacent heat exchange plate to form a first working medium flow channel; a lower arc groove is etched on the lower heat exchange plate, and the lower arc groove cavity cooperates with the adjacent heat exchange plate to form a second working medium flow channel; the groove openings of the upper arc groove and the lower arc groove face each other or are away from each other.

[0016] Preferably, the heat exchanger uses a double-layer countercurrent flow channel type functional heat exchange module, characterized in that it includes a tube box and a core located inside the tube box, the core being formed by two or more sets of double-layer countercurrent flow channel type functional heat exchange modules stacked sequentially along the flow channel stacking direction.

[0017] Preferably, the lower heat exchange plate of the current double-layer countercurrent flow channel functional heat exchange module and the upper heat exchange plate of the next double-layer countercurrent flow channel functional heat exchange module share the same plate body.

[0018] The beneficial effects of this invention are as follows:

[0019] 1) Through the above scheme, the present invention relies on the special design concept of "main and auxiliary flow separation and temperature difference de-icing". It relies on the main flow channel close to the cold source and the auxiliary flow channel relatively far away from the cold source to cooperate with each other. When in use, the dual cold source naturally makes each main flow channel form a specific stacked state of the first main flow channel, the first auxiliary flow channel, the second auxiliary flow channel and the second main flow channel.

[0020] Taking ethylene glycol aqueous solution and cryogenic LNG as examples: Due to the difference in flow area between the main flow channel and the auxiliary flow channel, during normal operation, the ethylene glycol aqueous solution mainly flows along the main flow channel, facilitating heat exchange with the cryogenic LNG in the adjacent working medium flow channel. When severe icing occurs, it mostly happens in the main flow channel; because the auxiliary flow channel is relatively farther from the working medium flow channel and has a relatively higher temperature, it is less prone to icing. At this time, as ice blocks the flow, the flow rate in the main flow channel decreases, and the flow rate in the auxiliary flow channel gradually exceeds that of the main flow channel. At this point, more ethylene glycol aqueous solution begins to enter the relatively unobstructed auxiliary flow channel. When the flow rate in the auxiliary flow channel is greater than that in the main flow channel, the auxiliary flow channel actually surpasses the main flow channel, thus forming a substitute flow channel for the main flow channel, achieving the purpose of continuous flow and heat exchange of the ethylene glycol aqueous solution.

[0021] When the auxiliary flow channel operates as a substitute flow channel, a portion of the ethylene glycol aqueous solution still flows into the main flow channel, continuously flushing the ice-covered areas and achieving a "mixing and melting" effect. Meanwhile, the remaining ethylene glycol aqueous solution entering the auxiliary flow channel, due to its proximity to the corresponding main flow channel, achieves indirect heat exchange with the main flow channel, thus serving a "heat exchange and melting" function. Throughout this process, the equipment can still operate without shutting down.

[0022] In summary, this invention, when localized icing occurs, utilizes an ethylene glycol aqueous solution as the heat exchange medium. Through cross-flow contact heat exchange and indirect heat exchange at the front and rear sides of the specific icing location, and cleverly leverages the "heat difference" generated by the varying distances between the main flow channel and the auxiliary flow channel and the cold source, it effectively enhances the "ice-melting effect" and fully ensures the flowability of the ethylene glycol aqueous solution. The combined effect of "mixed ice melting" and "heat exchange ice melting" enables continuous ice melting at the icing points in the main flow channel and even the auxiliary flow channel; it also ensures the self-cleaning function of the icing points without affecting the normal operation of the vaporizer. Simultaneously, by utilizing contact heat exchange and indirect heat exchange between the upper and lower heat source chambers, and even between the two flow channels within the same heat source chamber, the flowability of the ethylene glycol aqueous solution at the icing point is maintained, inhibiting the ice growth rate and thus ensuring the adaptability of the flow rate and temperature range control of the ethylene glycol aqueous solution.

[0023] 2) To maximize the "heat exchange and ice melting" effect, the optimized scheme of this invention can be used, namely, the second auxiliary flow channel is located within the projection range of the first main flow channel, and the second main flow channel is located within the projection range of the first auxiliary flow channel. At this time, the second auxiliary flow channel is closest to the first main flow channel while being relatively farthest from the cold source, thereby achieving a rapid heat exchange and ice melting effect on the first main flow channel; the same principle applies to the second main flow channel and the first auxiliary flow channel.

[0024] 3) In actual operation, the main channel and auxiliary channel of the present invention can have multiple coordination states: the auxiliary channel is formed by a combination of multiple independent channels, at which time the main channel is connected to each independent channel at the same time; or the inflection point of the auxiliary channel is the confluence point, while other areas are separated by a group or more baffles, which can also achieve the multi-channel effect of the auxiliary channel.

[0025] The aforementioned flow channel structure, combined with multiple rows of flow channel units, offers the following advantages: Firstly, the main and auxiliary flow channels within the same row of flow channel units can always redistribute flow at inflection points, ensuring the permeability of the ethylene glycol aqueous solution. Secondly, flow can also be redistributed between adjacent rows of flow channel units. The ethylene glycol aqueous solution can further enhance its permeability and ensure resistance to icing and fouling blockages through its own convergence, mixing, and diversion.

[0026] 4) The auxiliary flow channels employ a multi-channel parallel arrangement or a single channel with baffles. Another reason is to reduce the overall depth of the auxiliary flow channels, facilitating etching. Furthermore, the main flow channel and auxiliary flow channel are respectively opened at the two heat exchange plates, and then they are joined together to form corresponding heat source chambers. This not only increases the flow area of ​​the heat source chamber for ethylene glycol aqueous solutions, which are prone to freezing or fouling, but also allows the heat source chamber to exceed the 2mm etching depth limitation of conventional diffusion plate heat exchangers. Combined with a three-dimensional network formed by interconnected single or even multiple heat source chambers, the ethylene glycol aqueous solution can achieve continuous and intermittent combined flow patterns within a three-dimensional continuous and variable space, ensuring uniform heat exchange efficiency in each channel and further reducing the risk of freezing.

[0027] 5) The range of the angles formed between each main and auxiliary flow channel and the length direction of each heat exchange plate is limited. However, overall, along the length direction of the heat exchange plate, when the main and auxiliary flow channels of the same row of flow channel units extend outward from the base point, they are still far apart from each other in the direction of extension. They then approach each other at the farthest point and finally converge at a certain inflection point, repeating this process. This design method facilitates the formation of a three-dimensional network and makes processing more convenient. Attached Figure Description

[0028] Figure 1 and Figure 2 Cross-sectional view at the connection point of two installation methods in one embodiment of the heat exchanger;

[0029] Figure 3 This is a flow channel arrangement diagram of one implementation of the functional heat exchange module of the present invention.

[0030] Figure 4 for Figure 3 The front view;

[0031] Figure 5 for Figure 3 Top view of the structure shown;

[0032] Figure 6 This is a flow channel arrangement diagram for another implementation of the functional heat exchange module of the present invention.

[0033] Figure 7 for Figure 6 The front view;

[0034] Figure 8 for Figure 6 Top view of the structure shown;

[0035] Figure 9 This is a schematic diagram of another embodiment of the heat exchanger.

[0036] The actual correspondence between the reference numerals and component names in this invention is as follows:

[0037] 10a - First working medium flow channel; 10b - Heat exchange medium flow channel; 10c - Second working medium flow channel;

[0038] 11a - First main flow channel; 11b - First auxiliary flow channel; 12a - Second auxiliary flow channel; 12b - Second main flow channel;

[0039] 14-Upper heat exchange plate; 15-First heat exchange plate; 16-Second heat exchange plate; 17-Third heat exchange plate;

[0040] 18-Lower heat exchange plate; 19-Baffle plate. Detailed Implementation

[0041] For ease of understanding, this section combines... Figures 1-9 The specific structure and operation of the present invention are further described below:

[0042] To facilitate the explanation of the actual working process of the present invention, in the following description, the working medium is cryogenic LNG and the heat exchange medium is ethylene glycol aqueous solution; of course, in actual operation, the working medium and the heat exchange medium can be selected according to the site conditions.

[0043] Therefore, the specific structure of the present invention is as follows. Figures 1-8 As shown; it includes a tube box and a core located within the tube box. The tube box includes an upper end plate and a lower end plate, and the core is located between the two end plates. The core includes one or more double-layered counter-current flow channel functional heat exchange modules. Each functional heat exchange module has a built-in first working medium flow channel 10a, a second working medium flow channel 10c, and a heat exchange medium flow channel 10b, as shown. Figure 1 As shown. The first working medium flow channel 10a and the second working medium flow channel 10c constitute a cold source, while the heat exchange medium flow channel 10b constitutes a heat source, as shown. Figure 1 As shown.

[0044] The low-pressure LNG flow channel 10a and the high-pressure LNG flow channel 10c can be referenced. Figure 9 The heat exchanger type shown allows both cold sources to be arranged on the same side of the heat source. In this case, a side heat exchange plate with both low-pressure LNG and high-pressure LNG flow channels can be arranged above or below the first heat exchange plate. Alternatively, it can be arranged as follows... Figure 1 and Figure 2 The arrangement shown is on both sides of the heat source to achieve heat exchange.

[0045] For ease of description, here we will assume that the low-pressure LNG flow channel 10a and the high-pressure LNG flow channel 10c are located on both sides of the heat source, that is, as shown below. Figure 1 and Figure 2 The implementation methods shown are described below:

[0046] Furthermore, the dual-layer anisotropic flow channel functional heat exchange module is composed of various functional plates stacked in a specific order, including at least an upper heat exchange plate 14, a first heat exchange plate 15, a second heat exchange plate 16, a third heat exchange plate 17, and a lower heat exchange plate 18. In actual arrangement, the heat exchange plates are stacked on top of each other, thereby forming channel-like flow channel cavities from the etched groove-shaped corresponding flow channels. The combination method between the functional heat exchange modules... Figure 1 and Figure 2 The structure shown is a reference example; in actual operation, it can be set as appropriate according to the situation.

[0047] The upper heat exchange plate 14 and the lower heat exchange plate 18 can be arranged as a straight channel, a corrugated structure, or a sawtooth structure along the flow direction. A straight channel results in relatively low flow resistance, while a corrugated or sawtooth structure provides better heat exchange.

[0048] The main flow channel and auxiliary flow channel formed by the cooperation of the first heat exchange plate 15, the second heat exchange plate 16 and the third heat exchange plate 17, Figure 1 and Figure 2 This is also shown in the diagram. In actual design, the bottom dimension of each main channel, i.e., a single large trench, is the sum of the top dimensions of each auxiliary channel, i.e., multiple small trenches, and the dimensions of the solid connecting section in the middle. Furthermore, each trench is a wavy or sawtooth structure formed by bending along the length of the heat exchange plate; Figure 3 and Figure 6 As can be seen, on the same cross section, the flow directions of each main channel intersect, and the flow directions of each auxiliary channel also intersect. Furthermore, adjacent main channels and auxiliary channels also form an intersecting structure, thus forming a three-dimensional grid-like flow channel structure.

[0049] Specifically, when the main flow channel and the auxiliary flow channel are combined to form a corresponding heat source cavity, there are at least two possible combinations:

[0050] Example 1:

[0051] like Figures 3-5 As shown, the upper heat source cavity is formed by the combination of the first main flow channel 11a as a large trench and the first auxiliary flow channel 11b as parallel independent small trenches; the lower heat source cavity is formed by the second auxiliary flow channel 12a as parallel small independent trenches and the second main flow channel 12b as a large trench; and in the projection direction or the top view, the first auxiliary flow channel 11b is located directly above the second main flow channel 12b and arranged close to each other, while the first main flow channel 11a is located directly above the second auxiliary flow channel 12a and arranged close to each other, thus forming the above-mentioned cross structure.

[0052] Each single-channel segment of the first main flow channel 11a at the bottom of the first heat exchange plate 15 and each single-channel segment of the first auxiliary flow channel 11b at the top of the second heat exchange plate 16 are all the same length and have the same degree of deviation from the central axis. This makes the upper heat source cavity formed after the overall trench assembly present as follows: Figure 5 The diagram shows a regularly distributed diamond-shaped mesh flow channel structure. The lower heat source cavity formed by the second heat exchange plate 16 and the third heat exchange plate 17 is similar.

[0053] Example 2:

[0054] The basic structure of Example 2 is as follows Figures 6-8 As shown, the structure is similar to that of Embodiment 1. The difference is that the auxiliary flow channels of the parallel small trenches are not independent small trenches, but rather the entire groove is etched directly at the second heat exchange plate 16, and then the partition plate 19 is arranged on the groove, so that the parallel flow structure is formed by relying on the partition plate 19 to separate them.

[0055] It should be noted here that, from Figure 8 As can be seen, on the one hand, the partition 19 can be a protruding plate or an arc-shaped arch or any other physical separation structure; on the other hand, the number of partitions 19 can also be determined according to the situation, and can be one or more sets. At the same time, a certain space needs to be left at both ends of the partition 19 for the heat exchange medium, i.e., the ethylene glycol aqueous solution, to converge and mix.

[0056] For ease of understanding, the actual workflow of the present invention will be further described below with reference to Embodiment 1:

[0057] In practical use, this invention can be divided into two situations based on the flow state of the heat exchange medium inside the core, i.e., the ethylene glycol aqueous solution, during use: a conventional heat exchange condition where the channels are not blocked by ice or dirt, and a heat exchange condition where the channels are partially blocked by ice or dirt. These are described below:

[0058] 1) Conventional heat exchange conditions where there is no ice buildup or dirt clogging the channels:

[0059] At this time, the grooves in the upper heat exchange plate 14 and the lower heat exchange plate 18, together with the corresponding first heat exchange plate 15 or third heat exchange plate 17, form two working medium flow channels of the cold source respectively; the first heat exchange plate 15, the second heat exchange plate 16 and the third heat exchange plate 17 are paired with each other to form the corresponding upper heat source cavity and lower heat source cavity, and the upper heat source cavity and the lower heat source cavity are combined to form the heat exchange medium flow channel 10b.

[0060] The upper and lower heat source cavities have a wave-like or sawtooth-shaped flow structure, allowing the main and auxiliary channels within the same heat source cavity to connect at inflection points (i.e., connection points), ensuring that the ethylene glycol aqueous solution can flow freely within all channel units of the current heat source cavity. At the core inlet, refer to... Figure 3 As shown, the cross-sectional area of ​​the first main flow channel 11a accounts for more than 60% of the total cross-sectional area of ​​the upper heat source cavity. Thus, most of the ethylene glycol aqueous solution enters the first main flow channel 11a, forming the main flow channel; a small amount of ethylene glycol aqueous solution enters the first auxiliary flow channel 11b, forming an auxiliary flow channel. At this time, because the first main flow channel 11a is closer to the upper first cold source, it can fully perform indirect heat exchange, and the temperature of the ethylene glycol aqueous solution in the first main flow channel 11a is also lower. Correspondingly, the first auxiliary flow channel 11b is farther from the upper first cold source than the first main flow channel 11a, and performs insufficient indirect heat exchange; therefore, the temperature of the ethylene glycol aqueous solution in the first auxiliary flow channel 11b is relatively higher. The second main flow channel 12b and the second auxiliary flow channel 12a are similar. The ethylene glycol aqueous solutions in each flow channel will converge, exchange heat, and redistribute the flow rate at each inflection point, and then repeat the process of convergence and heat exchange until finally flowing out of the core.

[0061] 2) Conventional heat exchange conditions where channels are blocked by ice or dirt:

[0062] When severe icing occurs, the icing sites are mostly located in the main flow channels where the ethylene glycol aqueous solution has a relatively lower temperature, namely the first main flow channel 11a and the second main flow channel 12b. At this time, if the main flow channels are partially blocked, the ethylene glycol aqueous solution cannot easily pass through. The ethylene glycol aqueous solution naturally begins to use the auxiliary flow channel as the main flow channel, exchanging heat with the first cold source above. At this time, a portion of the ethylene glycol aqueous solution still flows into the main flow channel, continuously flushing the icing sites, achieving a "mixing and melting" effect; while the other portion of the ethylene glycol aqueous solution entering the auxiliary flow channel, because it is close to the corresponding main flow channel and the liquid temperature in the auxiliary flow channel is relatively higher, achieves indirect heat exchange with the corresponding main flow channel, playing a "heat exchange and melting" role. The combined effect of "mixing and melting" and "heat exchange and melting" enables continuous melting of the icing sites in the main flow channels, ensuring the self-cleaning function of the icing sites without affecting the normal operation of the vaporizer.

[0063] Of course, when one of the small channels in the auxiliary channel also freezes, the ice in the corresponding small channel can be melted entirely by the impact of the liquid and heat exchange between the walls due to the existence of other small channels and the connection points at each inflection point. This is one of the reasons why the auxiliary channel adopts a parallel channel structure with multiple channels.

[0064] It is now understood that the design concept of this invention is to treat all heat exchange plates as a whole, increase the hydraulic diameter by etching grooves and then joining them together, and when local icing occurs, the heat exchange medium exchanges heat through cross-flow contact heat exchange and indirect heat exchange at the front and rear sides of the specific icing position, and cleverly utilizes the "heat difference" generated by the different distances between the main flow channel and the auxiliary flow channel and the cold source, which effectively enhances the "ice melting effect" and fully ensures the flowability of the heat exchange medium.

[0065] Of course, if the flow channel is blocked by internal fouling generated during the heat exchange process or reaction process, the above design of the present invention can also prevent the flow channel from being completely blocked and unable to flow. That is, due to the existence of the three-dimensional flow system of the present invention, the blockage point only exists in a small area of ​​the large system. In particular, the corresponding main flow channel and auxiliary flow channel in this area can automatically switch with each other, so the flowability can still be guaranteed to ensure the continuous and reliable operation of the equipment.

[0066] Through the above design, the present invention can minimize the adverse effects of ice blockage or dirt blockage, and ensure the stable operation of the heat exchanger and system.

[0067] Of course, those skilled in the art will recognize that the present invention is not limited to the details of the exemplary embodiments described above, but also includes the same or similar structures that can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0068] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0069] The technologies, shapes, and structures not described in detail in this invention are all known technologies.

Claims

1. A dual-layer countercurrent flow channel functional heat exchange module, comprising a heat exchange plate and flow channels located within the heat exchange plate for the passage of the working medium and the heat exchange medium; characterized in that: The flow channels include a first working medium flow channel (10a) constituting a first cold source, a heat exchange medium flow channel (10b) constituting a heat source, and a second working medium flow channel (10c) constituting a second cold source; the heat exchange medium flow channel (10b) is a sequentially stacked structure of a first main flow channel (11a), a first auxiliary flow channel (11b), a second auxiliary flow channel (12a), and a second main flow channel (12b), and the first main flow channel (11a) and the first auxiliary flow channel (11b) are interconnected to form an upper heat source cavity, the second The main flow channel (12b) and the second auxiliary flow channel (12a) are connected to each other to form the lower heat source cavity; in the same heat source cavity, the flow area of ​​the main flow channel is larger than that of the auxiliary flow channel, and the main flow channel and the auxiliary flow channel intersect each other so that the intersection point constitutes a connection point that is connected to each other; along the stacking direction of the flow channels, the second auxiliary flow channel (12a) and the first main flow channel (11a) are adjacent to each other, the second main flow channel (12b) and the first auxiliary flow channel (11b) are adjacent to each other, and there is a gap between the upper heat source cavity and the lower heat source cavity; In the top-view projection, the second auxiliary channel (12a) is located within the projection range of the first main channel (11a), and the second main channel (12b) is located within the projection range of the first auxiliary channel (11b).

2. The dual-layer countercurrent flow channel functional heat exchange module according to claim 1, characterized in that: The upper heat source cavity and the lower heat source cavity are formed by three heat exchange plates. The lower surface of the first heat exchange plate (15) is provided with a grooved first main flow channel (11a), the upper surface of the second heat exchange plate (16) is provided with a grooved first auxiliary flow channel (11b), the lower surface of the second heat exchange plate (16) is provided with a grooved second auxiliary flow channel (12a), and the upper surface of the third heat exchange plate (17) is provided with a grooved second main flow channel (12b). The corresponding main flow channel and auxiliary flow channel are slotted together at the connection point to form the corresponding heat source cavity. Above the first heat exchange plate (15), an upper heat exchange plate (14) with a first working medium flow channel (10a) is arranged, and below the third heat exchange plate (17), a lower heat exchange plate (18) with a second working medium flow channel (10c) is arranged.

3. The dual-layer countercurrent flow channel functional heat exchange module according to claim 1, characterized in that: The upper heat source cavity and the lower heat source cavity are formed by three heat exchange plates. The lower surface of the first heat exchange plate (15) is etched with a grooved first main flow channel (11a), the upper surface of the second heat exchange plate (16) is etched with a grooved first auxiliary flow channel (11b), the lower surface of the second heat exchange plate (16) is etched with a grooved second auxiliary flow channel (12a), and the upper surface of the third heat exchange plate (17) is etched with a grooved second main flow channel (12b). The corresponding main flow channel and auxiliary flow channel are slotted together at the connection point to form the corresponding heat source cavity. A side heat exchange plate with a first working medium flow channel (10a) and a second working medium flow channel (10c) is also arranged above or below the first heat exchange plate (15).

4. A dual-layer counter-current flow channel functional heat exchange module according to claim 2 or 3, characterized in that: Each auxiliary flow channel is formed by two or more independent flow channels arranged side by side; each independent flow channel is independently connected to the corresponding main flow channel of the same heat source cavity at the connection point.

5. A dual-layer countercurrent flow channel functional heat exchange module according to claim 2 or 3, characterized in that: Taking the two adjacent intersections of the main flow channel and the auxiliary flow channel of the same heat source cavity as the two endpoints, a section of the auxiliary flow channel between the two endpoints forms a single flow channel segment, and a partition (19) is arranged in the single flow channel segment; the partition (19) extends along the length direction of the single flow channel segment, thereby dividing the flow channel cavity of the single flow channel segment into two or more isolation cavities; there is a distance between both ends of the partition (19) and the two endpoints.

6. A dual-layer countercurrent flow channel functional heat exchange module according to claim 2 or 3, characterized in that: Each main channel and each auxiliary channel has a V-shaped, W-shaped, or wavy shape. In the same heat source cavity, the openings of the main channels and auxiliary channels that cooperate with each other are opposite to each other, so that the openings of the main channels and auxiliary channels are matched to form a closed loop structure, and the connection point is set at the matching point of the closed loop structure. The turning point of the V-shaped or W-shaped main channels and auxiliary channels, or the peak or trough of the wavy main channels and auxiliary channels, are the inflection points of each channel. The main channels and auxiliary channels that cooperate with each other in the same heat source cavity form a row of channel units. The adjacent inflection points of the current row of channel units are connected to the next row of channel units in the same heat source cavity.

7. A dual-layer counter-current flow channel functional heat exchange module according to claim 6, characterized in that: The angle between each main flow channel and auxiliary flow channel and the length direction of each heat exchange plate ranges from 0° to 15°.

8. A dual-layer counter-current flow channel functional heat exchange module according to claim 2, characterized in that: The upper heat exchange plate (14) has an upper arc groove etched on its surface. The upper arc groove cavity cooperates with the adjacent heat exchange plate to form a first working medium flow channel (10a). The lower heat exchange plate (18) has a lower arc groove etched on its surface. The lower arc groove cavity cooperates with the adjacent heat exchange plate to form a second working medium flow channel (10c). The openings of the upper and lower arc grooves face each other or are away from each other.

9. A heat exchanger that uses a double-layer countercurrent flow channel functional heat exchange module as described in claim 2 or 3, characterized in that: It includes a tube box and a core located inside the tube box. The core is formed by stacking two or more sets of double-layered, opposite-flow channel functional heat exchange modules in sequence along the flow channel stacking direction.

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