Freeze-thaw resistant roadbed heat pipe fin structure

Abstract

The utility model discloses a freeze-thaw resistant roadbed heat pipe fin structure which comprises a heat pipe body filled with a heat exchange working medium, the lower portion of the heat pipe body is used for being placed in a roadbed frozen soil layer, the upper portion of the heat pipe body is provided with heat dissipation fins and exposed out of the air for heat dissipation, and each heat dissipation fin is provided with a plurality of turbulent flow penetrating holes in the thickness direction. The turbulent flow penetrating holes are used for forming through flow and cross flow when air flow passes through the heat dissipation fins and are regularly arranged on the surfaces of the heat dissipation fins. The turbulent flow penetrating holes are formed in the radiating fins, so that ambient air flow forms through flow and cross flow when passing through the radiating fins, the air turbulent flow intensity among the radiating fins is enhanced, an air film on the surface of a heat release section at the upper part of the heat pipe body is effectively reduced, the gas-solid heat conduction coefficient is improved, and the gas-solid heat transfer process is enhanced; therefore, the heat exchange efficiency of the heat dissipation fins is enhanced, and the heat dissipation effect of the heat release section of the heat pipe body is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of roadbed heat pipes, in particular to a freeze-thaw resistant roadbed heat pipe fin structure. Background Art

[0002] Permafrost refers to land that remains frozen for three years or more under natural conditions, and is primarily distributed in cold regions at high latitudes or altitudes. Unlike roadbed engineering in conventional areas, the engineering properties of roadbed soil and its underlying soil layer in permafrost areas primarily depend on the solid-liquid phase transformation process of water in the soil caused by alternating positive and negative temperatures and fluctuations. Therefore, the impact of temperature on the stability of frozen soil roadbeds is crucial, and thermal stability in frozen soil roadbeds is the key to roadbed stability. The engineering geological problems caused by the destruction of thermal stability of frozen soil roadbeds include: thermal thaw subsidence caused by a decrease in the upper limit; changes in roadbed stability caused by changes in the strength and rheological properties of permafrost foundation soil; roadbed diseases caused by adverse frozen soil phenomena (such as ice cones and frost heaves); and uneven frost heave diseases caused by the freezing and thawing of the active layer.

[0003] A roadbed heat pipe, also known as a heat rod, is a highly efficient heat-conducting device made of seamless carbon steel pipe. The lower portion (heat-absorbing section) is buried directly in permafrost, while the upper portion (heat-releasing section) is exposed and equipped with fins. The interior is filled with a low-boiling-point liquid heat exchange medium. When the ambient temperature is lower than the permafrost surrounding the heat rod's heat-absorbing section, the liquid in the heat rod absorbs heat from the permafrost and evaporates into vapor. Driven by the pressure differential within the pipe, the vapor flows upward along the central channel of the heat rod to the upper portion. Upon encountering the cooler pipe wall, it releases its latent heat of vaporization and condenses into liquid. Under the influence of gravity, it flows back along the pipe wall to the heat-absorbing section, where it evaporates again. This repetitive cycle dissipates heat from the permafrost in the foundation to the atmosphere. Due to the heat rod's one-way heat transfer, it stores a large amount of cold in the permafrost in winter, preventing it from melting in summer and forming a "permafrost layer." This strengthens the permafrost and effectively prevents frost heave and thaw settlement during operation of railways and highways built on permafrost.

[0004] The heat release section of existing heat pipes primarily utilizes ambient temperature for heat dissipation, and therefore typically operates in winter but not in summer. However, due to factors such as relatively high summer temperatures and strong thermal radiation, as well as the vibration and heating of the roadbed caused by moving vehicles, frozen roadbeds can also thaw to some extent, leading to subsidence. Improving the freeze-thaw resistance of frozen roadbeds is a key issue currently being addressed by roadbed heat pipes. Utility Model Content

[0005] In response to the problems existing in the above-mentioned prior art, the utility model provides a freeze-thaw-resistant roadbed heat pipe fin structure. By improving the heat dissipation fin structure, the heat exchange efficiency between the heat dissipation fin and the environment is increased, thereby improving the heat dissipation effect of the heat release section of the heat pipe, thereby improving the working efficiency of the heat pipe and enhancing the freeze-thaw-resistant effect.

[0006] In order to achieve the above purpose, the technical solution adopted by the present utility model is as follows:

[0007] A freeze-thaw resistant roadbed heat pipe fin structure includes a heat pipe body with a heat exchange medium inside. The lower part of the heat pipe body is used to be placed in the roadbed frozen soil layer, and the upper part is provided with heat dissipation fins and exposed to the air for heat dissipation. Each of the heat dissipation fins is provided with a plurality of turbulent perforations along the thickness direction, which are used to form throughflow and crossflow when the airflow passes through the heat dissipation fins. The turbulent perforations are regularly arranged on the surface of the heat dissipation fins.

[0008] Preferably, the turbulent perforations on adjacent heat dissipation fins are staggered.

[0009] Furthermore, an inner flow channel is provided in the heat dissipation fin, and an interface communicating with the inner flow channel is configured on the surface of the heat dissipation fin, and the interface is used for an external cooling medium to enter the inner flow channel to cool the inside of the heat dissipation fin.

[0010] Furthermore, a heat dissipation medium pipe body that is tightly fitted with the heat dissipation fins is embedded in the inner flow channel, and the heat dissipation medium pipe body is sealed and connected to an external cooling medium pipeline through an interface to form a cooling medium circulation.

[0011] Furthermore, the heat dissipation fins are made of a sponge-like porous foam metal material.

[0012] Furthermore, the heat dissipation medium tube body is provided with micro-holes for the cooling medium to seep out.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] (1) This utility model improves the fin structure of the traditional roadbed heat pipe based on the technical idea of ​​enhancing heat dissipation. Turbulent perforations are opened on the heat dissipation fins, so that the ambient air flow forms throughflow and crossflow when passing through the heat dissipation fins, thereby enhancing the gas turbulence intensity between the heat dissipation fins, effectively reducing the gas film on the surface of the heat dissipation section of the upper part of the heat pipe body, improving the gas-solid thermal conductivity coefficient, and strengthening the gas-solid heat transfer process, thereby enhancing the heat exchange efficiency of the heat dissipation fins and improving the heat dissipation effect of the heat dissipation section of the heat pipe body. This utility model has a clever design, simple structure, excellent effect, low cost, and is suitable for application in roadbed heat pipes.

[0015] (2) The utility model utilizes the staggered arrangement of turbulent perforations to improve the effect of forming gas turbulence and enhance the heat dissipation efficiency.

[0016] (3) The present invention configures an internal flow channel in the heat dissipation fin, which can be connected to an external cooling medium to enhance the heat dissipation of the heat dissipation fin, further improving the heat dissipation effect of the heat dissipation fin.

[0017] (4) The present invention embeds a heat dissipation medium tube body in the internal flow channel, thereby facilitating the formation of a cooling cycle of the external cooling medium pipeline, improving the stability of the heat dissipation medium circulation through the heat dissipation fins, and ensuring the performance of enhanced cooling; and by making the heat dissipation fins of foam metal material, the contact area between the heat dissipation fins and the environment is further increased, further improving the heat dissipation effect; and it can also cooperate with the micropores provided on the tube body to allow liquid to seep onto the heat dissipation fins when the cooling medium is selected to be low-cost deep well frozen water, thereby converting the original gas-solid conduction heat dissipation into liquid-solid conduction heat dissipation and phase change heat transfer, further enhancing the heat dissipation effect of the heat dissipation fins. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present utility model.

[0019] Figure 2 This is a schematic structural diagram of the heat dissipation fins in an embodiment of the present invention.

[0020] Figure 3 This is a schematic structural diagram of the heat dissipation fins in another embodiment of the present invention.

[0021] Figure 4 This is a schematic structural diagram of a heat dissipation fin in yet another embodiment of the present invention. DETAILED DESCRIPTION

[0022] The present invention will be further described below with reference to the accompanying drawings and examples. The implementation methods of the present invention include but are not limited to the following examples.

[0023] Example

[0024] like Figures 1 to 4As shown, the anti-freeze-thaw roadbed heat pipe fin structure includes a heat pipe body 1 with a heat exchange medium inside, the lower part of the heat pipe body is used to be placed in the roadbed frozen soil layer, and the upper part is provided with heat dissipation fins 2 and exposed to the air for heat dissipation. Each of the heat dissipation fins is provided with a plurality of turbulent perforations 10 along the thickness direction, and the turbulent perforations are regularly arranged on the surface of the heat dissipation fins. Preferably, the turbulent perforations on adjacent heat dissipation fins are staggered. In this embodiment, when the airflow generated by the wind in the environment passes through the heat dissipation fins, through-flow and cross-flow are formed between the heat dissipation fins through the turbulent perforations, which effectively increases the gas turbulence intensity between the heat dissipation fins, thereby effectively reducing the air film on the tube wall and the fin surface of the heat dissipation section of the upper heat pipe body (formed by the wind and airflow acting on the tube wall surface and the fin gap, which affects heat conduction to a certain extent), improving the gas-solid heat conduction coefficient, strengthening the gas-solid heat transfer process, increasing the heat dissipation efficiency of the heat dissipation section of the heat pipe body, and improving the heat dissipation capacity.

[0025] In another embodiment, Figure 3 As shown, the heat sink 2 is provided with an internal flow channel 11. The surface of the heat sink is provided with an interface 12 connected to the internal flow channel. The interface is used to allow an external cooling medium to enter the internal flow channel to cool the interior of the heat sink. Generally, an inlet interface and an outlet interface are provided to facilitate the relatively complete passage of the external cooling medium through the interior of the heat sink to promote cooling. The external cooling medium primarily comes from the coolant of other enhanced heat sink devices, such as the refrigerant of an external air pump refrigeration unit, frozen water collected from a deep well by an external pump, natural water collected from the nearby environment by a pump, or water generated by an external wind-solar hybrid cooling system.

[0026] In another embodiment, Figure 4 As shown, when the external cooling medium is a high-value material (such as refrigerant), to reduce its loss and optimize usage costs, the internal flow channel 11 is embedded with a heat dissipation medium tube 13 that fits tightly with the heat dissipation fins. This heat dissipation medium tube is sealed and connected to the external cooling medium pipeline via an interface to form a cooling medium circulation. This ensures the cooling medium is used in a stable circulation, ensuring enhanced cooling effect while reducing usage costs.

[0027] In another embodiment, Figure 4As shown, the heat sink fins are made of a foam metal material in a sponge porous state. In practical applications, such heat sink fins can adopt a structure in which a metal skeleton is wrapped with foam metal, which not only ensures the connection performance between the heat sink fins and the heat pipe body, but also increases the contact area between the heat sink fins and the ambient space by the foam metal material, thereby improving the heat dissipation effect. On this basis, when a low-cost cooling medium (such as deep well frozen water currently collected) is used, micropores for the cooling medium to seep out can be set on the heat sink medium tube body, and corresponding seepage channels can also be configured in the heat sink fins. In this way, the cooling medium can seep out to the surface of the heat sink fins, forming a water film, converting the original gas-solid heat conduction mode into a liquid-solid heat conduction mode and phase change heat transfer, highly strengthening the heat transfer process, thereby effectively increasing the heat dissipation efficiency of the heat sink fins.

[0028] Through the above methods, the utility model effectively improves and enhances the thermal conductivity of the heat release section (especially the heat dissipation fin part) on the upper part of the heat pipe body without changing the basic structure of the roadbed heat pipe, so that the heat released by the heat release section can be more efficiently conducted and dissipated into the environment, thereby increasing the working efficiency of the heat pipe and enhancing the heat release effect in the frozen soil roadbed.

[0029] In addition, the medium passing through the internal flow channel or the heat dissipation medium pipe body can also use non-cooling medium, such as water with a certain temperature generated by an external wind-solar complementary cooling system, which can be used to dynamically adjust the heat transfer direction and intensity on the heat dissipation fins to achieve heat release speed or blocking for the heat release section of the heat pipe.

[0030] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any changes based on the design principles of the present invention and any changes made through non-creative work on this basis shall fall within the scope of protection of the present invention.

Claims

1. A freeze-thaw resistant roadbed heat pipe fin structure, comprising a heat pipe body containing a heat exchange medium, the lower portion of the heat pipe body being placed in the frozen soil layer of the roadbed, and the upper portion being provided with heat dissipation fins and exposed to the air for heat dissipation, characterized in that: Each of the heat dissipation fins is provided with a plurality of turbulent flow holes along the thickness direction, which are used to form through-flow and cross-flow when the air flows through the heat dissipation fins. The turbulent flow holes are regularly arranged on the surface of the heat dissipation fins.

2. The freeze-thaw resistant roadbed heat pipe fin structure according to claim 1, characterized in that: The turbulence perforations on adjacent heat dissipation fins are staggered.

3. The freeze-thaw resistant roadbed heat pipe fin structure according to claim 1 or 2, characterized in that: An inner flow channel is provided in the heat dissipation fin, and an interface communicating with the inner flow channel is provided on the surface of the heat dissipation fin. The interface is used for an external cooling medium to enter the inner flow channel to cool the inside of the heat dissipation fin.

4. The freeze-thaw resistant roadbed heat pipe fin structure according to claim 3, characterized in that: A heat dissipation medium pipe body that is tightly fitted with the heat dissipation fins is embedded in the inner flow channel, and the heat dissipation medium pipe body is sealed and connected to an external cooling medium pipeline through an interface to form a cooling medium circulation.

5. The freeze-thaw resistant roadbed heat pipe fin structure according to claim 4, characterized in that: The heat dissipation fins are made of a sponge-like porous foam metal material.

6. The freeze-thaw resistant roadbed heat pipe fin structure according to claim 5, characterized in that: The heat dissipation medium pipe body is provided with micro holes for the cooling medium to seep out.

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