A finned heat sink for an outdoor transformer

Abstract

The present application relates to the technical field of transformer heat dissipation, and particularly relates to a sheet type radiator for outdoor transformer. The sheet type radiator comprises a plurality of radiating fins, a liquid inlet header, a liquid outlet header, a heat collecting shed, a plurality of flow guide belts, a light-heat component and a heat storage component. The heat collecting shed comprises a contraction cover, an air suction port and an exhaust chimney. The air suction port is in communication with an air flow channel around the radiating fins. The flow guide belts are made of flexible material, the top end of the flow guide belts is deep into the air suction port, and the bottom end of the flow guide belts is deep into the air flow channel around the radiating fins. The present application converts solar energy into heat through the heat collecting shed and the light-heat component, heats the air in the heat collecting shed, combines the acceleration effect of the contraction cover and the chimney effect of the exhaust chimney, makes the hot air exhaust to high altitude, and forms negative pressure suction to promote the air rising between the radiating fins. The flexible flow guide belts have the functions of flow guiding, flow disturbing and dust cleaning. The heat storage component can maintain the high efficiency heat dissipation of the sheet type radiator in rainy days and at night.

Description

Technical Field

[0001] This invention relates to the field of transformer heat dissipation technology, and more specifically to a plate-type heat sink for outdoor transformers. Background Technology

[0002] When a transformer is running, the load current flowing through the transformer windings generates a large amount of heat. This heat must be dissipated in time, otherwise it will cause the transformer to overheat. Transformer oil is generally used as the coolant to carry away the heat generated by the transformer, and then the transformer oil is air-cooled by plate radiators. In the existing technology, plate radiators generally use parallel and equidistant heat sink groups to increase the heat exchange area. These heat sink groups are connected in parallel, and the coolant is collected by manifolds at the inlet and outlet, and then connected to the transformer oil tank. The oil in the transformer oil tank is heated, its temperature rises, its density decreases, and it rises. The oil in the flow channels of each heat sink is cooled by the outside cold air, its temperature drops, its density increases, and it falls, forming a natural circulation on the oil side. The air between the heat sinks is heated, its temperature rises, its density decreases, and it rises. Hot air is discharged from above the heat sinks, and cold air is drawn in from below the heat sinks, forming a natural circulation on the air side.

[0003] In existing technologies, plate-type heat sinks are generally exposed. When transformers are used outdoors, especially in summer or under direct sunlight, the air temperature is already high, and solar radiation brings additional heat, which can easily reduce the temperature difference between the inside and outside of the plate-type heat sink, thus reducing its heat dissipation capacity. As transformer power increases, heat sinks are often densely arranged. On the one hand, this results in limited space for air intake, potentially leading to a short circuit between the air supply and exhaust, causing the intake air temperature to be too high and reducing heat dissipation capacity. On the other hand, the airflow velocity outside the heat sink is reduced, mainly resulting in a laminar flow state with high thermal resistance, further reducing heat dissipation capacity. In summary, current transformer plate-type heat sinks lack the means to cope with outdoor radiant heating and high-temperature, low-velocity intake air. Summary of the Invention

[0004] The purpose of this invention is to provide a plate-type heat sink for outdoor transformers, so as to solve the technical problem that the heat dissipation capacity of current plate-type heat sinks for transformers is reduced under outdoor radiant heating and high temperature and low speed air intake conditions.

[0005] To address the aforementioned technical problems, this invention provides a plate-type radiator for outdoor transformers, comprising: a plurality of heat sinks, each heat sink having a coolant flow channel within it, and an air flow channel forming around the heat sink; an inlet manifold connected to the inlets of all coolant flow channels of the heat sink; an outlet manifold connected to the outlets of all coolant flow channels of the heat sink; a heat collection shed positioned above the heat sinks, comprising a surrounding shrinkage shroud, a bottom air intake, and a top exhaust chimney; the top cross-sectional area of ​​the shrinkage shroud is smaller than the bottom cross-sectional area; the air intake communicates with the air flow channels around the heat sinks; a plurality of guide strips made of flexible material, the top ends of the guide strips extending into the air intakes, and the bottom ends of the guide strips extending into the air flow channels around the heat sinks; a solar thermal component for converting solar energy into heat energy and heating the surrounding air; and a heat storage component that absorbs heat when the surrounding air temperature is higher than a first preset temperature and releases heat when the surrounding air temperature is lower than a second preset temperature.

[0006] Optionally, the photothermal component is a photothermal material attached to the outer surface of the heat collection shed, and the area of ​​the heat collection shed in contact with the photothermal component is made of a thermally conductive material.

[0007] Optionally, the shrink shroud is made of a light-transmitting material, the photothermal assembly is arranged inside the air intake, and the photothermal assembly includes a concentrator, a heat absorber, and a light-tracking mechanism.

[0008] Furthermore, the thermal storage component array is arranged inside the air intake, with gaps between adjacent thermal storage components.

[0009] Furthermore, the guide strip is made of a thermally conductive material, and the top end of the guide strip is connected to the thermal storage component.

[0010] Furthermore, the guide strip is connected to several fins via a thermosensitive expansion connector. When the temperature is higher than its preset temperature, the thermosensitive expansion connector expands to open the fins.

[0011] Furthermore, the lower end of the air intake extends a given distance below the upper end of the heat sink.

[0012] Furthermore, several guide strips arranged around the air intake are interconnected to form an enclosing curtain, surrounding the heat sink at a given distance below the upper end.

[0013] Furthermore, a dust removal component is provided on the guide belt.

[0014] The beneficial effects of this invention are as follows: the solar collector acts as a shade, reducing solar radiation's heating of the radiator and surrounding air, thus preventing a decrease in the radiator's heat dissipation capacity under sunlight; the solar collector absorbs solar energy to further heat the air above the radiator, and combined with the accelerating effect of the shrink hood and the chimney effect of the exhaust chimney, the hot air is discharged into the upper atmosphere. This effectively prevents hot air from accumulating around the radiator and causing excessively high radiator intake air temperature; furthermore, the pressure inside the solar collector decreases after the hot air is discharged, creating a negative pressure suction effect, promoting upward airflow between the radiator fins, increasing air velocity and the amount of cold air entering, effectively improving heat dissipation performance; as the transformer power increases, the temperature of the upward-flowing air around the radiator fins also rises, further enhancing the efficiency of the solar collector's discharge and suction. The force will also be passively increased, thereby increasing the airflow velocity and improving heat dissipation performance; the guide strip connects the air intake and the airflow channel around the heat sink, forming an upward airflow channel, which can prevent the increase of resistance caused by air turbulence. Moreover, the guide strip is made of flexible material. The guide strip that penetrates into the airflow channel around the heat sink will vibrate and swing when the air flows, which can increase air turbulence, effectively destroy the boundary layer, improve the heat transfer performance on the air side, and also play a role in cleaning dust when it comes into contact with the surface of the heat sink; the solar thermal component further improves the effect of the solar collector shed in absorbing solar energy and converting it into air heat energy; the thermal storage component can absorb heat when the air temperature inside the solar collector shed is high and release heat when the air temperature inside the solar collector shed is low, maintaining the efficient heat dissipation of the plate heat sink under conditions such as cloudy and rainy days and nights. Attached Figure Description

[0015] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0016] Figure 1 This is a schematic diagram of the structure of a plate-type heat sink for an outdoor transformer according to an embodiment of the present invention;

[0017] Figure 2 This is a schematic diagram of the structure of the heat collection shed, the flow guide belt, the photothermal component, and the heat storage component according to an embodiment of the present invention;

[0018] Figure 3 This is a schematic diagram of the flow guide band when the fins are not open, according to an embodiment of the present invention.

[0019] Figure 4 This is a schematic diagram of the flow guide band when the fins are open, according to an embodiment of the present invention.

[0020] Figure 5 This is a schematic diagram of the flow guide strip forming a curtain according to an embodiment of the present invention;

[0021] In the picture:

[0022] Heat sink 1, liquid inlet manifold 2, liquid outlet manifold 3, heat collection shed 4, shrink hood 41, air intake 42, exhaust chimney 43, guide strip 5, thermal expansion connector 51, fins 52, photothermal component 6, heat storage component 7. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments implemented by those skilled in the art without creative effort are within the protection scope of the present invention. Example

[0024] This embodiment provides a plate-type heat sink for outdoor transformers, and its structural schematic diagram is shown below. Figure 1 and Figure 2 As shown, the system includes several parallel-arranged heat sinks 1, an inlet manifold 2, and an outlet manifold 3. Each heat sink 1 has a coolant flow channel, and an air flow channel is formed around it, allowing the coolant inside the heat sink 1 to exchange heat with the outside air. The inlet manifold 2 connects to the inlets of all coolant flow channels of the heat sink 1, and is used to disperse the transformer oil heated by the transformer into the coolant flow channels of each heat sink. The outlet manifold 3 connects to the outlets of all coolant flow channels of the heat sink 1, and is used to collect the transformer oil from all coolant flow channels of the heat sink 1 and return it to the transformer.

[0025] It also includes a heat collection shed 4, which is positioned above the heat sink 1. The heat collection shed 4 includes a shrink shroud 41 around its perimeter, an air intake 42 at the bottom, and an exhaust chimney 43 at the top. The top cross-sectional area of ​​the shrink shroud 41 is smaller than the bottom cross-sectional area. The air intake 42 is connected to the airflow channel around the heat sink 1. The heat collection shed 4 above the heat sink 1 serves as a shading device, reducing the heating of the radiator and the surrounding air by solar radiation. Under the sun, the solar collector shed 4 absorbs heat from the air inside. The air temperature rises and its density decreases, causing it to rise. Furthermore, the cross-sectional area of ​​the contraction hood 41 decreases towards the top, further increasing the air's upward speed. Combined with the chimney effect of the exhaust chimney 43, the high-speed hot air can be discharged into the upper atmosphere, effectively preventing hot air from accumulating around the radiator and causing an increase in the radiator's intake temperature. After the hot air is exhausted, the pressure inside the solar collector shed 4 decreases, creating a negative pressure suction effect. Since the air intake 42 is connected to the airflow channels around the heat sink 1, the air between the heat sink 1 accelerates upward under the pressure difference. This, combined with the buoyancy caused by the density difference between the air between the heat sink 1, effectively increases the airflow velocity and the amount of cold air entering, improving heat dissipation performance. When the transformer power increases, the temperature of the upward-flowing air around the heat sink 1 also rises, passively increasing the exhaust and suction capacity of the solar collector shed 4, thereby increasing the airflow velocity and improving heat dissipation performance.

[0026] It also includes several guide strips 5, made of flexible material. The top of the guide strips 5 extends into the air intake 42, and the bottom extends into the airflow channel around the heat sink 1. The guide strips 5 divide the space from the air intake 42 to the airflow channel around the heat sink 1 into independent guide channels. Within these guide channels, air can only rise, effectively reducing lateral airflow turbulence, thereby reducing resistance and increasing airflow velocity. Moreover, the guide strips 5, made of flexible material, also act as turbulence-disrupting ribbons. Airflow is not completely uniform; under the influence of the non-uniform flow field and its own inertia, the guide strips 5 will continuously vibrate and oscillate. Since the guide strips extend into the airflow channel around the heat sink 1, their disturbance can effectively disrupt the laminar boundary layer and increase the convective heat transfer coefficient on the air side. When the guide strips 5 oscillate, they will contact the surface of the heat sink 1, also serving a dust-cleaning function. It is important to note that the mass of the guide strips 5 should be moderate. If the mass is too large, the disturbance intensity will decrease; if the mass is too small, they may be completely blown away, losing their guiding and turbulence-disrupting effects.

[0027] It also includes a solar thermal component 6, which is used to convert solar energy into heat energy and heat the surrounding air. The solar thermal conversion capacity of the solar collector shed 4 is limited. The specialized solar thermal component 6 further improves the effect of the solar collector shed 4 in absorbing solar energy and converting it into air heat energy. The higher the air temperature inside the solar collector shed 4, the higher the height of the hot air exhaust at the outlet of the exhaust chimney 43, the stronger the negative pressure suction capacity below the air intake 42, the greater the air velocity around the heat sink 1, and the stronger the disturbance of the guide strip 5.

[0028] It also includes a heat storage component 7, which absorbs heat when the ambient air temperature is higher than a first preset temperature and releases heat when the ambient air temperature is lower than a second preset temperature. When solar radiation is insufficient, neither the solar collector shed 4 nor the solar thermal component 6 can effectively convert light and heat. At this time, relying solely on the accelerating effect of the shrink hood 41 and the chimney effect of the exhaust chimney 43, although it can still increase the height of hot air exhaust and the airflow velocity around the heat sink 1, the effect is significantly reduced, and the negative pressure suction below the intake port 42 and the disturbance of the guide band 5 will be significantly weakened. The function of the heat storage component 7 is to store excess heat when the sun is strong or the transformer power is high, and release heat when the air temperature inside the solar collector shed 4 decreases. This ensures that even on cloudy or rainy days or at night, the high-efficiency exhaust and suction capacity of the solar collector shed 4 can be maintained, thereby extending the heat dissipation enhancement effect. The first preset temperature is not lower than the second preset temperature, and the second preset temperature is higher than the air temperature at the outlet above the airflow channel of the heat sink 1.

[0029] Specifically, the photothermal component 6 can be a photothermal material attached to the outer surface of the heat collection shed 4, and the area of ​​the heat collection shed 4 in contact with the photothermal component 6 is made of a thermally conductive material. The photothermal material absorbs solar radiation and converts it into heat energy, which is then conducted through the heat collection shed 4 to heat the air inside the heat collection shed 4. The photothermal material can be a metal nanomaterial (such as gold nanoparticles, silver nanoparticles), a semiconductor material (such as black TiO2, MoO3 quantum dots), or a carbon-based material (graphene, carbon nanotubes, etc.). This arrangement is simple and flexible, does not add too much weight or complex structure, and can be arranged on the entire outer surface of the heat collection shed 4.

[0030] Another optional arrangement to improve the photothermal effect is to use a light-transmitting material for the shrink hood 41, with the photothermal component 6 arranged inside the air intake 42. The photothermal component 6 includes a concentrator, a heat absorber, and a tracking mechanism. This modular arrangement allows the photothermal component 6 to be detached from the heat collection shed 4, effectively preventing damage to the photothermal component 6 due to damage to the heat collection shed 4. Furthermore, placing the photothermal component 6 inside the heat collection shed 4 reduces damage from external environmental factors such as dust and rain, and allows the heat generated by the photothermal component 6 to be fully used to heat the air inside the heat collection shed 4, reducing heat dissipation to the outside. Depending on the concentrating principle, the photothermal component 6 can be one or more of a parabolic trough system, a linear Fresnel reflector system, a dish concentrator system, or a tower concentrator system, all of which are existing technologies. Furthermore, several photothermal components 6 can be arranged in an array within the air intake 42, which can act as a uniform distribution plate to make the flow field more uniform. The heat absorption efficiency of different heat absorbers can also be adjusted by controlling the light-tracking mechanism, thereby adjusting the temperature field within the heat collection shed 4, thereby increasing the air velocity around a specific heat sink 1, and indirectly achieving effects such as clearing the coolant flow channel and external dust removal.

[0031] To make the temperature and flow fields within the heat collection shed 4 more uniform, the heat storage components 7 can be arranged in an array within the air intake 42, with gaps between adjacent heat storage components 7. The arrayed heat storage components 7 form a uniform distribution structure that promotes a uniform flow field, while the arrayed heat sources (absorbing or releasing heat) also make the temperature field more uniform.

[0032] To further improve the temperature uniformity within the heat collection shed 4, the guide strip 5 is made of thermally conductive material, and its top end is connected to the heat storage component 7. The highly thermally conductive tape 5 acts as a temperature equalization plate and also increases the heat exchange area of ​​the heat storage component 7.

[0033] To enhance the turbulence effect of the guide strip 5 and prevent it from adhering to the heat sink 1, several fins 52 are connected to the guide strip 5 via thermal expansion connectors 51, such as... Figure 3 As shown, when the temperature exceeds its preset temperature, the thermal expansion connector 51 expands, causing the fins 52 to open, as... Figure 4As shown. The thermal expansion connector 51 can be a bimetallic strip or a thermally expandable polymer material. If the temperature of the thermal expansion connector 51 increases, one possibility is that the heat sink cannot cool the transformer in time. In this case, opening the fins 52 on the guide strip 5 can enhance the turbulence effect, thereby strengthening heat dissipation. Another possibility is that the guide strip 5 adheres to the surface of the heat sink 1. In this case, opening the fins 52 on the guide strip 5 can cause the guide strip 5 to spring away from the surface of the heat sink 1.

[0034] To reduce the amount of outside air that does not exchange heat with the heat sink 1 entering the heat collection chamber 4, the lower end of the air intake 42 extends a given distance below the upper end of the heat sink 1. Thus, for air to enter the air intake 42, it must first pass through the heat exchange area surrounding the heat sink 1.

[0035] Another arrangement to reduce air leakage is to have several guide strips 5 arranged around the air intake 42 interconnected to form an enclosed curtain, such as... Figure 5 As shown, the airflow guide 5 surrounds the heat sink 1 at a given distance below the top. In this way, the curtain formed by the airflow guide 5 can completely surround the heat sink 1, forming a windproof curtain wall. Air can only enter the air intake 42 from the bottom of the heat sink or the bottom of the curtain wall, effectively extending the contact path between the air and the heat sink 1.

[0036] To improve the dust removal effect of the guide belt 5, a dust removal component is provided on the guide belt 5. The dust removal component can be a wiping component (such as tassels, bristles, wiping cloth, screen, etc.) or a sound wave generator (such as a whistle structure, diaphragm whistle structure and Hartmann whistle structure).

[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A plate-type radiator for outdoor transformers, characterized in that, include: A plurality of heat sinks (1), wherein a coolant flow channel is provided in the heat sink (1), and an air flow channel is formed around the heat sink (1); Liquid inlet manifold (2), which is connected to all the coolant flow channel inlets of the heat sink (1); The liquid outlet manifold (3) is connected to all the coolant flow channel outlets of the heat sink (1); A heat collection shed (4) is arranged above the heat sink (1). The heat collection shed (4) includes a shrink hood (41) around the perimeter, an air intake (42) at the bottom, and an exhaust chimney (43) at the top. The top cross-sectional area of ​​the shrink hood (41) is smaller than the bottom cross-sectional area. The air intake (42) is connected to the air flow channel around the heat sink (1). A plurality of guide strips (5), the guide strips (5) being made of flexible material, the top end of the guide strips (5) extending into the air intake (42), and the bottom end of the guide strips (5) extending into the air flow channel around the heat sink (1); A solar thermal component (6) is used to convert solar energy into thermal energy and heat the surrounding air; The heat storage component (7) absorbs heat when the ambient air temperature is higher than a first preset temperature and releases heat when the ambient air temperature is lower than a second preset temperature. The thermal storage components (7) are arranged in an array within the air intake (42), with gaps between adjacent thermal storage components (7); The guide strip (5) is made of thermally conductive material, and the top end of the guide strip (5) is connected to the heat storage component (7); The guide strip (5) is connected to a number of fins (52) by a thermosensitive expansion connector (51). When the temperature is higher than the preset temperature, the thermosensitive expansion connector (51) expands to open the fins (52). The lower end of the air intake (42) extends to a given distance below the upper end of the heat sink (1).

2. The plate-type heat sink for outdoor transformers according to claim 1, characterized in that, The photothermal component (6) is a photothermal material attached to the outer surface of the heat collection shed (4), and the area of ​​the heat collection shed (4) in contact with the photothermal component (6) is made of a thermally conductive material.

3. The plate-type heat sink for outdoor transformers according to claim 1, characterized in that, The shrink hood (41) is made of a light-transmitting material, and the photothermal component (6) is arranged inside the air intake (42). The photothermal component (6) includes a concentrator, a heat absorber, and a light-tracking mechanism.

4. The plate-type heat sink for outdoor transformers according to any one of claims 1 to 3, characterized in that, The air intake (42) is surrounded by several guide strips (5) that are connected to each other to form an enclosing curtain that surrounds the heat sink (1) at a given distance below the top.

5. The plate-type heat sink for outdoor transformers according to claim 4, characterized in that, A dust removal component is provided on the guide belt (5).

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