Fin structure, radiator and fuel cell cooling system

Abstract

The fin structure comprises a plurality of long and thin fins which are arranged at intervals in parallel, an airflow channel allowing cooling air to flow through in the longitudinal direction of the fins is defined between the opposite main side faces of every two adjacent fins, and a corrugated part extending in the longitudinal direction of the fins is formed on each fin. The fins are arranged in the mode that the wave crests and the wave troughs of the corrugated parts of the adjacent fins are aligned in the arrangement direction of the fins, and the wave troughs and the wave troughs of the corrugated parts of the adjacent fins are aligned in the arrangement direction of the fins. The wave crest in each corrugated unit of the corrugated part deviates from the central plane between the two adjacent wave troughs and approaches the inclined slope extending between the wave crest and the wave trough in the adjacent corrugated units of the corrugated part of the adjacent fin. The invention also relates to a radiator with the fin structure and a fuel cell cooling system with the radiator.

Description

Technical Field

[0001] The present invention relates to the technical field of fuel cell cooling systems, and in particular to a fin structure for a radiator, a radiator having the fin structure, and a fuel cell cooling system having the radiator. Background Art

[0002] In the fuel cell cooling system, the coolant flows through the coolant flow channel between the cathode and anode plates of the fuel cell stack, relying on the forced convection heat exchange of the coolant to take away the heat generated during the operation of the fuel cell. The coolant can be deionized water or a mixture of water and ethylene glycol. The heated coolant dissipates heat in the radiator, thereby reducing the temperature of the coolant, and then the cooled coolant is sent to the fuel cell stack to continue cooling the stack.

[0003] In terms of the radiator design of the fuel cell cooling system, the fuel cell cooling system has great challenges compared to the conventional diesel system cooling water system, which is mainly reflected in the following two points: 1) The required heat exchange amount increases. The heat exchange of the water tank of the traditional diesel system accounts for about 33% of the engine power, while the heat exchange requirement of the radiator of the fuel cell system is as high as 2 to 3 times that of the former; 2) The heat exchange temperature difference with the ambient air is reduced. The heat exchange temperature difference between the water temperature of the water tank of a traditional fuel vehicle and the ambient air temperature is about 55 degrees, while the operating temperature of the fuel cell is relatively low, and the heat exchange temperature difference between the cooling water temperature of the fuel cell system and the ambient air temperature is about 28 degrees. If the traditional radiator layout and fin form continue to be used in fuel cell vehicles, a larger radiator and a larger layout space are required to meet the heat exchange requirements of the fuel cell, which further increases the difficulty of the interior space design of the fuel cell vehicle, and also means that the fuel cell vehicle is bulky and more expensive.

[0004] Accordingly, the present invention is directed to overcoming one or more of the above-mentioned problems. Summary of the invention

[0005] In response to the cooling problem of fuel cells, the present invention proposes an improved fin structure for the radiator of the fuel cell cooling system, which can enhance the heat exchange capacity of the radiator to meet the heat exchange requirements and reduce the size of the radiator and the fuel cell cooling system (water tank size and fan size), thereby reducing the system cost.

[0006] According to one aspect of the present invention, there is provided a fin structure for a radiator, comprising a plurality of slender fins spaced apart from each other and arranged in parallel, an air flow channel for cooling air to flow through the fins in the longitudinal direction defined between the relative main side surfaces of two adjacent fins, a corrugated portion extending in the longitudinal direction of the fin being formed on each fin, the fins being arranged so that the crests and troughs of the corrugated portions of adjacent fins are aligned in the fin arrangement direction, and characterized in that the crests in each corrugated unit of the corrugated portion deviate from the center plane between two adjacent troughs and approach the inclined slope extending between the crests and troughs in the adjacent corrugated units of the corrugated portion of the adjacent fins.

[0007] Advantageously, relative to the airflow direction in the airflow channel, the inclined slope surfaces of each corrugated unit of the corrugated portion are divided into an upward inclined surface and a downward inclined surface, and the upward inclination angle of the upward inclined surface relative to the longitudinal direction of the fin is greater than the downward inclination angle of the downward inclined surface relative to the longitudinal direction of the fin.

[0008] Advantageously, the corrugated units of the corrugated portion of each fin have the same corrugated cross section.

[0009] Advantageously, each fin is formed with the corrugations over its entire length.

[0010] Advantageously, the fin structure is formed as an integral component, comprising the fin and a connecting base located at an edge side of the fin.

[0011] Advantageously, the integrated component extends in a pulse waveform as a whole along the arrangement direction of the fins, wherein adjacent edge sides of the fins are connected via connecting bases at the crests and troughs of the pulse waveform.

[0012] The fin structure according to the present invention utilizes the undulating contour structure in the air flow channel to disturb the air flow, thereby inducing turbulence to improve the heat transfer efficiency, so as to reduce the size of the cooling system (water tank size, fan size), reduce costs, and solve the problem that the cooling water system on existing fuel cell vehicles is bulky and costly.

[0013] According to another aspect of the present invention, there is provided a radiator for a fuel cell cooling system, comprising a radiator core, the radiator core comprising: a plurality of generally flat fluid tube plates spaced apart and arranged in parallel along the thickness direction of the radiator core, each fluid tube plate defining a plurality of fluid flow channels for a fluid to be cooled to flow through; and a fin group arranged between adjacent fluid tube plates, the fin group having the above-mentioned fin structure.

[0014] Advantageously, the fluid flow channel extends along the length direction of the radiator core, and the air flow channels are arranged side by side in the length direction of the radiator core.

[0015] According to another aspect of the present invention, there is provided a fuel cell cooling system, comprising a fuel cell and a radiator configured to cool the fuel cell, wherein the fuel cell and the radiator are fluidically connected to form a cooling circuit in which a coolant circulates, and wherein the radiator is the radiator described above, and the coolant flows as a fluid to be cooled into a fluid flow channel defined in a fluid tube plate of a radiator core.

[0016] According to the fuel cell cooling system of the present invention, a radiator with improved heat transfer efficiency and designed to be small enough is effectively utilized, thereby reducing the size of the entire fuel cell cooling system (the size of the cooling unit, the water tank and the fan) and reducing the system cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Features and advantages of one example of the present invention will become apparent with reference to the following detailed description and accompanying drawings, in which:

[0018] Figure 1 A three-dimensional schematic diagram showing a heat sink according to the present invention;

[0019] Figure 2 A three-dimensional schematic diagram showing a heat dissipation unit of a radiator core of a radiator according to the present invention;

[0020] Figure 3 Show Figure 2 A three-dimensional schematic diagram of a portion of a heat dissipation unit after removing a fluid tube sheet on one side;

[0021] Figure 4 A schematic diagram showing a partial section of a fin structure according to the present invention;

[0022] Figure 5 A schematic diagram showing the flow state in the air flow channel of the fin structure according to the first embodiment of the present invention;

[0023] Figure 6 A schematic diagram showing the flow state in the air flow channel of the fin structure according to the second embodiment of the present invention; and

[0024] Figure 7 A schematic diagram showing a fuel cell cooling system according to the present invention is shown. DETAILED DESCRIPTION

[0025] Reference will now be made in detail to various embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings to refer to the same or like parts.

[0026] See also Figure 1As shown, the radiator 10 for a fuel cell cooling system according to the present invention includes a radiator core 100 and a flow divider chamber 101 and a flow collecting chamber 102 located at both ends of the radiator core. The inlet pipe 101a is in fluid communication with the flow divider chamber 101 so that the fluid to be cooled enters the flow divider chamber. The fluid discharged from the radiator core enters the flow collecting chamber 102 and flows out through the outlet pipe 102a. The radiator core 100 includes a plurality of generally flat fluid tube sheets 1001 spaced apart and arranged in parallel along the thickness direction T of the radiator core, and a fin group 1002 arranged between adjacent fluid tube sheets. Adjacent fluid tube sheets and the fin group arranged between the adjacent fluid tube sheets constitute a basic heat dissipation unit.

[0027] Figure 2 The heat dissipation unit U of the radiator core 100 of the radiator of the present invention is shown in FIG. In the heat dissipation unit embodiment shown, each fluid tube plate 1001 is defined with a plurality of fluid flow channels extending along the length direction L of the radiator core. In the example shown, the fluid to be cooled (coolant of the fuel cell cooling system) enters the fluid flow channel from the inlet located on the upper side and flows out from the outlet located on the lower side. The fin group 1002 includes a plurality of slender corrugated fins F extending along the width direction W of the radiator core. The fins are spaced apart from each other and arranged in parallel in the length direction of the heat dissipation unit, thereby defining an air flow channel for cooling air AIR to flow through between the opposite main sides of adjacent fins F. The air flow channel generally extends along the width direction of the heat dissipation unit (i.e., a direction parallel to the longitudinal direction of the fins) and is arranged side by side in the length direction of the heat dissipation unit. The cooling air AIR enters the air flow channel from an inlet located at one end side of the air flow channel in the width direction of the heat dissipation unit, and exchanges heat with the fluid to be cooled in the fluid flow channel of the fluid tube plate during flowing through the air flow channel. As a result, the temperature of the fluid to be cooled is reduced, and the air with increased temperature flows out from an outlet located at the other end side of the air flow channel in the width direction.

[0028] Figure 3 A perspective schematic diagram is shown of a fin group 1002 disposed between fluid tube plates. Figure 4 Show Figure 3 A side view of a section of a fin assembly along the length of a heat sink core is shown. Figure 5 A schematic diagram of a waveform cross section of a portion of the corrugated portion of the fin is shown. According to the present invention, the fin group in each heat dissipation unit has such a fin structure: each fin is formed with a corrugated portion BP extending in the longitudinal direction of the fin over its entire length, and a plurality of fins are arranged so that the crests and troughs of the corrugated portions of adjacent fins are aligned in the fin arrangement direction, wherein the crests in each corrugated unit BPU of the corrugated portion deviate from the center plane between two adjacent troughs and approach the inclined slope extending between the crests and troughs in the adjacent corrugated units of the corrugated portion of the adjacent fin.

[0029] In the specific embodiment shown, relative to the airflow direction in the airflow channel, each corrugated unit BPU of the corrugated portion has an upslope inclined surface SL-u and a downslope inclined surface SL-d, wherein the upslope inclination angle α of the upslope inclined surface relative to the longitudinal direction FL of the fin is greater than the downslope inclination angle β of the downslope inclined surface relative to the longitudinal direction FL of the fin. For example, the upslope inclination angle is about 60 degrees, and the downslope inclination angle is about 30 degrees. Preferably, the corrugated units of the corrugated portion of each fin have the same wave cross section. That is, the characteristic parameters such as the connection fillet at the crest, the connection fillet at the trough, the wave pitch, the wave amplitude, the upslope inclined surface or the downslope inclined surface are all the same.

[0030] See also Figure 5 As shown, the air entering the airflow channel must experience a movement similar to uphill or downhill during the flow process. The following uses a downhill-uphill-downhill movement process in the airflow channel GC as an example to explain the change in the flow state of the airflow:

[0031] Under the restriction of the downhill sections AB and A'B', the airflow flows along the inclined downhill passage to the trough area. At the trough area, the airflow hits the bottom wall to form a vortex, and then the airflow rushes up the uphill passage defined by the uphill sections CD and C'D'. Since the uphill inclination angle of each corrugated unit is greater than the downhill inclination angle, the uphill passage is shorter than the downhill passage. The airflow easily climbs up the uphill passage with the help of the impact force of the vortex. In addition, halfway through the uphill passage, due to the bias of the wave crest to the inclined slope (uphill section), the uphill passage forms a cross-sectional reduction section Re in the corresponding area. The airflow is accelerated due to the throttling effect when flowing through the cross-sectional reduction section Re. The accelerated airflow directly scours the top wall of the downstream wave crest and rushes into the downhill passage defined by the downhill sections EF and E'F'. At the top wall of the wave crest, the airflow scours the top wall to form a vortex, and due to the flow inertia, the airflow will rush directly to the inner wall of the downhill section E'F' to avoid any laminar flow at the wave crest. Following the downhill passage that is longer than the uphill passage, the airflow is rectified and rushes to the trough to form a vortex. Then, the airflow flows to the next uphill passage with the help of the vortex. In this way, the airflow periodically goes downhill-uphill-downhill in the entire airflow passage, and switches between the diffusion-contraction-diffusion movement mode until it is discharged from the airflow passage.

[0032] During the entire flow process, the airflow basically moves in a turbulent state, the speed changes all the time, and there are fierce collisions in all directions, which reduces laminar flow or flow dead corners, destroys the laminar boundary layer, and enhances convective heat exchange. Therefore, the heat transfer efficiency is greatly improved.

[0033] Therefore, the fin structure in the illustrated embodiment according to the present invention can greatly improve the heat transfer efficiency of the fins and thus enable the heat sink to be designed as small as possible.

[0034] Although the upslope angle in the embodiment shown in the figure is greater than the downslope angle, it can be understood that the upslope angle α can be set to be smaller than the downslope angle β, which can also ensure that the heat exchange efficiency is greatly improved compared to the traditional sinusoidal fins. Figure 6 As shown, the airflow with a certain speed flows to the wave crest area through the uphill passage defined by the uphill sections AB and A'B', forming a vortex, and at the same time goes down to the downhill passage defined by the downhill sections CD and C'D', and then accelerates after passing through the cross-sectional reduction section Re, rushes to the bottom wall of the wave trough area, forming a vortex, and then, with the flow momentum of the vortex, rushes to the uphill passage defined by the uphill sections EF and E'F'. Such periodic switching of the diffusion-contraction-diffusion motion mode can also strengthen turbulence to a certain extent, destroy the laminar boundary layer, and improve the heat transfer efficiency.

[0035] In order to further improve the heat transfer efficiency, each fin in the fin group is advantageously arranged to be formed with the corrugated portion over its entire length.

[0036] Replay Figure 3 and Figure 4 The fin assembly according to the present invention is preferably formed as an integral component, with the fin F being connected by a connecting base BC located at the edge side of the fin. t and B.C. b In the exemplary embodiment shown, the integrated fin group extends in a zigzag manner along the length direction of the radiator core in a pulse waveform, that is, the adjacent edge sides of the fins are connected via the connection base BC at the peak of the pulse waveform. t and the connecting base BC at the trough of the pulse waveform b The connection base is fixed to the adjacent fluid tube sheet by welding. The connection base is preferably a flat connection portion, thereby providing a larger welding area for welding between the fin group and the fluid tube sheet. Therefore, the composite fin structure according to the present invention is easy to be stamped from a sheet and easy to be welded to the fluid tube sheet.

[0037] Although Figure 1 The heat sink shown in FIG. 5 is a plate-fin heat exchanger, but a belt-and-tube heat exchanger may also be used.

[0038] According to the present invention, a highly efficient fuel cell cooling system 1 can be obtained by means of a radiator with greatly improved heat exchange effect under a certain volume. Figure 7 As shown, the fuel cell cooling system 1 includes a fuel cell 11 and the above-mentioned radiator 10 for cooling the fuel cell. Figure 7As shown, the fuel cell cooling system 1 includes a cooling circuit 20 in which a coolant circulates, and a fuel cell 11 and a radiator 10 are arranged in the cooling circuit. The coolant circulating in the cooling circuit takes away heat from the fuel cell, and then flows into the fluid flow channel defined in the fluid tube plate in the radiator core of the radiator, exchanges heat with the air, cools down the coolant, and finally flows out of the radiator, and under the action of the pump, flows back into the fuel cell. This cycle repeats.

[0039] Industrial Applicability

[0040] In order to facilitate the understanding of the present invention, the assembly method and working principle of the radiator of the present invention are described below:

[0041] See also Figure 1 As shown, a plurality of fluid tube sheets 1001 are provided, and the fluid tube sheets are arranged in a vertical posture along the thickness direction of the radiator core, and a fin group 1002 is arranged between every two adjacent fluid tube sheets in the following manner: the slender corrugated fins F of the same configuration are arranged at a certain interval in the vertical direction (the length direction of the radiator core), so that the longitudinal direction of the fins F is basically consistent with the width direction of the radiator core, and the wave crests in each corrugated unit of the corrugated part deviate from the center plane between two adjacent troughs and face the airflow direction. When all fin groups 1002 are preassembled between adjacent fluid tube sheets or between the fluid tube sheet and the side sheet and the connection base of the fin group is attached to the side of the fluid tube sheet, they are fixed by brazing or the like, thereby obtaining the radiator core 100. A flow distribution chamber 101 is installed at the upper end of the radiator core, and a flow collection chamber 102 is installed at the lower end of the radiator core, thereby realizing that the coolant flows into the radiator core and is discharged from the radiator core in a predetermined manner.

[0042] Thus, the assembled radiator 10 works in a predetermined manner: the coolant flows into the fluid flow channel of the fluid tube plate of the radiator core, and exchanges heat with the air flowing into each air flow channel, after which the cooled coolant is discharged from the radiator and the heated air is discharged into the external environment. The cooled coolant from the radiator then enters the fuel cell to cool the fuel cell, and the coolant discharged from the fuel cell carrying the fuel cell reaction heat then enters the radiator for cooling.

[0043] The radiator according to the present invention makes it possible to improve the heat exchange effect without changing the shell size (i.e., the radiator size and the fan size), thereby greatly reducing the manufacturing cost of the fuel cell cooling system. In addition, due to the design and use of high-efficiency fins, the length of the air flow channel can be reduced, thereby achieving a favorable balance between the increase in heat exchange capacity and the increase in flow resistance. In addition, the width direction dimension of the heat dissipation unit of the present invention can be designed to be smaller, and the arrangement and layout method is more flexible. With the application of the above-mentioned high-efficiency fins, the radiator of the present invention has a heat exchange performance far superior to that of existing radiators without expanding the overall volume.

[0044] The above merely describes an exemplary embodiment of a radiator and a fuel cell cooling system according to the present invention. The structure / configuration of the radiator is not limited to the specific embodiments described herein, but rather, each component may be used independently and individually relative to other components described herein. "An example", "another example", "example", etc., mentioned throughout the specification, means describing that a certain element / element (such as a feature, structure and / or characteristic) associated with the example is included in at least one example described herein and may and / or may not appear in other examples. In addition, it is understood that multiple elements of any example described may be combined in any suitable manner in multiple different examples, unless the context clearly indicates otherwise.

[0045] This specification uses examples to disclose the present invention, including the best embodiment, and enables any person skilled in the art to implement the present invention. The patentable scope of the present invention is defined by the claims, and may include other examples that may occur to those skilled in the art. If these other examples have structural elements that are not distinguished from the literal language of the claims, or if these other examples include structural elements that are not substantially distinguished from the literal language of the claims, then these other examples should fall within the scope of the claims.

Claims

1. A fin structure for a heat sink, comprising a plurality of slender fins spaced apart from each other and arranged in parallel, an air flow channel for cooling air to flow through along the longitudinal direction of the fins is defined between the opposite main sides of two adjacent fins, each fin is formed with a corrugated portion extending in the longitudinal direction of the fin, the fins are arranged so that the crests and troughs of the corrugated portions of adjacent fins are aligned in the fin arrangement direction, characterized in that: The wave crests in each corrugated unit of the corrugated portion deviate from the center plane between two adjacent wave valleys and approach the inclined slope extending between the wave crests and wave valleys in the adjacent corrugated units of the corrugated portion of the adjacent fin.

2. The fin structure according to claim 1, characterized in that: Relative to the airflow direction in the airflow channel, the inclined slopes of each corrugated unit of the corrugated portion are divided into an upward inclined surface and a downward inclined surface, and the upward inclination angle of the upward inclined surface relative to the longitudinal direction of the fin is greater than the downward inclination angle of the downward inclined surface relative to the longitudinal direction of the fin.

3. The fin structure according to claim 1 or 2, characterized in that: The corrugated units of the corrugated portion of each fin have the same corrugated cross section.

4. The fin structure according to any one of claims 1 to 3, characterized in that: Each fin is formed with the corrugated portion over its entire length.

5. The fin structure according to any one of claims 1 to 4, characterized in that: The fin structure is formed as an integral component, comprising the fin and a connecting base located at an edge side of the fin.

6. The fin structure according to claim 5, characterized in that: The integral component extends in a pulse waveform as a whole along the arrangement direction of the fins, wherein adjacent edge sides of the fins are connected via connecting bases at the crests and troughs of the pulse waveform.

7. A radiator for a fuel cell cooling system, comprising a radiator core, the radiator core comprising: A plurality of generally flat fluid tube plates spaced apart and arranged in parallel along the thickness direction of the radiator core, each fluid tube plate defining a plurality of fluid flow channels for the fluid to be cooled to flow therethrough; and a fin group arranged between adjacent fluid tube plates, the fin group having a fin structure according to any one of claims 1 to 6.

8. The heat sink according to claim 7, characterized in that: The fluid flow channel extends along the length direction of the radiator core, and the air flow channels are arranged side by side in the length direction of the radiator core.

9. A fuel cell cooling system, comprising a fuel cell and a radiator configured to cool the fuel cell, the fuel cell and the radiator being fluidically connected to form a cooling circuit in which a coolant circulates, characterized in that: The radiator is the radiator according to claim 7 or 8, and the coolant, as the fluid to be cooled, flows into the fluid flow channel defined in the fluid tube plate of the radiator core.

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