CN218380615U - Bionic enhanced heat transfer heat pipe - Google Patents

Abstract

The utility model discloses a bionic enhanced heat transfer heat pipe, which comprises a pipe wall, a liquid absorption core and a working medium which is filled in the pipe body and circularly flows in the pipe body, wherein the liquid absorption core is arranged at the inner side of the pipe wall, and the heat pipe comprises a condensation section, an evaporation section and a heat insulation section which is positioned between the condensation section and the evaporation section; the outer wall surfaces of the condensation section and the evaporation section are provided with bulges distributed in a thread shape or a ring shape; the surface of the bulge is a bionic surface which is wavy; be provided with the bionical pore from protruding top inwards extension along the heat pipe circumferencial direction on bionical surface, bionical pore is the gradual change hole that the aperture diminishes from top to bottom gradually. The utility model provides a heat pipe adopt the heat conduction inequality and the lower problem of heat exchange efficiency that exist when "omega" type imbibition core, strengthened the heat transfer function of heat pipe. The heat pipe system is suitable for heat pipe systems related to energy sources including a movable small reactor, can be widely applied to the fields of space, deep sea, medical emergency energy sources and the like, and has wide application prospects.

Description

Bionic enhanced heat transfer heat pipe

Technical Field

The utility model belongs to energy field and mechanical equipment field including nuclear energy, concretely relates to heat pipe that bionic structure can reinforce heat transfer.

Background

The heat pipe is a device for transferring heat by latent heat of vaporization, which is invented by the national laboratory of Los Alamos in the sixties of the twentieth century, maintains working medium circulation two-phase heat transfer by relying on the actions of capillary force, gravity, centripetal force and the like, and has high heat transfer efficiency. It can be embedded in metal plate to make heat exchange, and can also add fins to the interior and exterior of heat pipe to make fluid heat exchange. Compared with the traditional heat exchange mode, the heat pipe heat exchanger can transmit heat through a small cross section area in a longer distance, and in the working process of the heat pipe, no additional power or energy is needed for driving. The research and application range of heat pipes is also getting larger and larger based on the advantages of heat pipe heat exchangers.

The application of heat pipes to space reactor power systems was proposed by the university of new mexico in the united states as early as the 21 st century. In recent years, numerous researches on heat pipe cooling reactor schemes and key technologies are carried out in countries around the world, and after 3 historical stages of concept initiative (1960 to 2000), active exploration (2000 to 2012) and major breakthrough (2012 to the present), a complete heat pipe cooling reactor design scheme type spectrum in a power interval of 1kW to 10MW is formed. In recent years, along with the proposal of the concept of carbon peak-reaching carbon neutralization and the policy of positive safe and orderly nuclear power development, the heat pipe small stack gradually becomes a research hotspot at home and abroad. At present, the design of a heat pipe cooling reactor is mostly less than 200kW of electric power, which is related to the application history of space nuclear energy of the heat pipe cooling reactor to some extent, and the typical power requirement of an early space nuclear power supply is 10 to 100kW. At the moment, more and more demand and application scenarios of near megawatts or more than 1MW emerge. In order to make the power of the heat pipe cooling reactor reach near megawatt level or megawatt level and be suitable for various application occasions, the current research work mainly focuses on improving the inherent safety and the heat exchange efficiency. For the small heat pipe stacks, the improvement of the heat exchange performance of the small heat pipe stacks can not only enhance the economic benefit, but also provide guarantee for the inherent safety of the small heat pipe stacks.

At present, liquid absorption core structures in heat pipes have various forms, and can be generally divided into a single-structure liquid absorption core and a composite-structure liquid absorption core. Wherein the single-structure liquid absorption core comprises a winding wire mesh core, a metal sintering core, an axial groove core, an annular core, a crescent core, a trunk road core and the like; the composite structure liquid absorption core comprises a wire mesh composite core, a wire mesh covered groove core, a plate-shaped trunk road core, a tunnel-type core and the like. Good wicks require high capillary pressure, low liquid flow resistance, i.e., high permeability, large cross-sectional area, however, large cross-sectional areas increase radial thermal resistance, which is detrimental to heat transfer. Taking an omega-shaped liquid absorption core in the axial groove liquid absorption core as an example, the groove is designed to ensure that the cross section of the groove is uneven, the channel part sunken towards the pipe wall is thinner, the heat conduction thermal resistance between the groove and the wall of the heat pipe is small, the heat conduction performance is good, the rest part is thicker, the heat conduction performance is poor, the heat conduction efficiency between the liquid absorption core and the heat pipe is low, the heat conduction is uneven, and the economical efficiency and the safety are poor.

Therefore, aiming at the problems, the structure optimization design is carried out on the heat pipe by adopting a bionic means and imitating a butterfly vein guide hole structure used for heat dissipation on the human skull and a fold structure of an African elephant ear, so that the heat exchange can be strengthened, and the economy and the safety of the heat pipe heat exchanger are improved.

Disclosure of Invention

The utility model provides a bionical enhanced heat transfer heat pipe, its technical purpose is solved the heat pipe and is adopted when groove formula imbibition core by the peculiar thin uneven of groove structure and the heat conduction inequality that the cross-sectional area caused greatly and the lower problem of heat exchange efficiency, strengthens the heat transfer function of heat pipe.

The above technical object of the present invention can be achieved by the following technical solutions:

a bionic enhanced heat transfer heat pipe comprises a pipe wall, a liquid absorption core and a working medium which is filled in the pipe body and circularly flows in the pipe body, wherein the liquid absorption core is arranged on the inner side of the pipe wall, and the heat pipe comprises a condensation section, an evaporation section and a heat insulation section positioned between the condensation section and the evaporation section; the method is characterized in that: the outer wall surfaces of the condensation section and the evaporation section are provided with protrusions in a threaded or annular distribution; the surface of the protrusion is a bionic surface which is wavy; bionic pores extending inwards from the top of the protrusion are arranged on the bionic surface along the circumferential direction of the heat pipe, and the bionic pores are gradually changed holes with the pore diameters gradually reduced from top to bottom.

Furthermore, the outer surfaces of the condensation section and the evaporation section are provided with super-hydrophobic surfaces and are formed by nano coatings, the nano coatings are made of SiO2 or Al or Ti or V, and the contact angle theta of the super-hydrophobic surfaces is larger than 150 degrees.

Furthermore, the structure of the omega-shaped wick core is designed to be similar to the shape of a lotus leaf edge, namely, the convex part inside the heat pipe is in an arc shape, the thickness of the thinnest part is from 2mm to 4mm, the thickness of the thickest part is from 7mm to 10mm, the curvature radius range of the convex part is from 2.5mm to 3.5mm, the curvature radius range of the groove part is from 1.5mm to 2mm, and the distance between two adjacent convex parts is from 7mm to 9mm.

Furthermore, the fine hole extends inwards to the inside of the protruding part of the liquid absorption core, the shape of the fine hole is similar to a butterfly vein guiding hole in the human skull, the fine hole is conical, the length of the fine hole ranges from 7mm to 10mm, the diameter of the tip end ranges from 0.5mm to 1mm, the diameter of the root end ranges from 2mm to 3mm, meanwhile, the pipe wall part around the fine hole is inwards recessed, and the diameter of the pipe wall part is 0.6mm to 1mm.

Furthermore, the folds are uniformly distributed in a thread shape, the height of the folds is 3mm to 4mm, the width of the bottom edge of the folds is 4mm to 6mm, the folds are irregular and wavy in an African trunk imitating manner, the folds are formed by connecting a plurality of arc-shaped protrusions with different curvature radiuses and a plurality of arc-shaped grooves with different curvature radiuses, the curvature radius range of the maximum arc-shaped protrusion is 0.35mm to 0.5mm, the curvature radius range of the minimum arc-shaped protrusion is 0.25mm to 0.4mm, the curvature radius range of the maximum arc-shaped groove is 0.3mm to 0.4mm, and the curvature radius range of the minimum arc-shaped groove is 0.2mm to 0.3mm.

Further, the thickness of the heat insulation sleeve is 3mm to 7mm; the thickness of the pipe wall is 4mm to 8mm; the length of the heat insulation segment is 200mm to 400mm; the length of the evaporation segment is 300mm to 600mm; the length of the condensation section is 200mm to 400mm.

Further, the material of the outer surface of the pipe wall is 5A06 aluminum magnesium alloy or graphene oxide.

Furthermore, the fine hole is positioned at the top of the triangular threaded fold, the position of the fine hole corresponds to each bulge on the liquid absorption core, the pipe wall part which is inwards sunken is coated with the fine hole in a water-drop shape, the minimum curvature radius of the sunken part is 0.6 mm-1.5 mm, and the maximum curvature radius is 1mm-2mm.

The beneficial effects of the utility model reside in that: the structural design of the heat pipe adopts a bionic means, a butterfly vein guide hole structure for connecting a vein and a scalp to radiate heat and a corrugation structure for radiating African elephant ear on a human skull are imitated, the structure of the outer wall of the heat pipe and the structure of the liquid suction core are optimized, pores are uniformly distributed on the wall surface of the heat pipe and extend inwards to the inside of the convex part of the liquid suction core, meanwhile, the pipe wall part around the pores is inwards sunken, the liquid suction core and the local area of the pipe wall are thinned, the radial heat exchange between the omega-shaped liquid suction core and the pipe wall is more uniform, the heat exchange area between the pipe wall and an external flowing working medium is increased, and the heat conduction between the liquid suction core and the wall of the heat pipe and the convection heat exchange between the wall of the heat pipe and the external working medium are enhanced; meanwhile, the outer wall of the heat pipe is provided with the thread-shaped uniformly-distributed folds to enhance the heat convection, the heat conduction between the liquid absorption core and the pipe wall is uneven at the fold concave part of the wall surface of the heat pipe, but the pipe wall is thinner relative to the fold convex part, the heat loss is small in the heat conduction process, and the heat conduction in the axial direction of the pipe wall is relatively even. The structure solves the problems of uneven heat conduction and lower heat exchange efficiency when the heat pipe adopts the omega-shaped liquid absorption core, strengthens the heat exchange function of the heat pipe, and proves that the structure can improve the heat exchange efficiency of the heat pipe by about 30 percent and can further improve the economy and the safety of the heat pipe heat exchanger.

Drawings

FIG. 1 is a schematic structural view of a bionic enhanced heat transfer heat pipe according to the present application;

FIG. 2 isbase:Sub>A cross-sectional view taken along line A-A of FIG. 1;

FIG. 3 is a cross-sectional view taken along line B-B of FIG. 1;

FIG. 4 is a cross-sectional view taken along line C-C of FIG. 1;

FIG. 5 is an enlarged view of portion A of FIG. 2;

fig. 6 is a schematic structural view of the pleats.

In the figure: 1-a pipe body; 2-a condensation section; 3-an adiabatic section; 4-an evaporation section; 5-pores; 6-pleating; 7-direction of liquid flow near wick; 8-the direction of gas flow in the heat pipe; 9-an insulating sleeve; 10-a wick; 11-condensation section pipe wall; 12-heat insulation section pipe wall; 13-evaporation section tube wall; 14-recessed part of pipe wall around the pore; 15-working medium inside the heat pipe; h-fold structure height; l-fold structure width.

Detailed Description

The technical solution of the present application will be described in detail below with reference to the accompanying drawings.

Fig. 1 is the structural schematic diagram of the bionic enhanced heat transfer heat pipe, and with reference to fig. 2, the heat pipe comprises a pipe body 1, a condensation section 2, a heat insulation section 3 and an evaporation section 4 are arranged in the pipe body 1 from left to right, the outer layers of the condensation section 2, the heat insulation section 3 and the evaporation section 4 are a condensation section pipe wall 11, a heat insulation section pipe wall 12 and an evaporation section pipe wall 13, the thickness of the condensation section pipe wall is 4mm to 8mm, the inner surface of the condensation section pipe wall is connected with a liquid absorption core 10, and the outer layer of the heat insulation section pipe wall 12 is provided with a heat insulation sleeve 9, and the thickness of the heat insulation section pipe wall is 3mm to 7mm. The length of the heat insulation section is 200mm to 400mm; the length of the evaporation segment is 300mm to 600mm; the length of the condensation segment is 200mm to 400mm

This application heat pipe body 1's one end is condensation segment 2, and body 1's the other end is evaporation zone 4, is adiabatic section 3 between condensation segment 2 and evaporation zone 4, and three-section pipeline internal diameter is the same, is the straight pipeline. The pipe body 1 is filled with working medium 15 which flows circularly, and the types of the working medium 15 in the heat pipe are determined according to the actual temperature.

The heat pipe is externally circulated with medium, such as water, air, liquid metal, supercritical CO2 and the like.

The flow of the heat pipe inside and outside the pipe can be concurrent flow in the same direction or countercurrent flow or cross flow in the opposite direction. It can be forced circulation or natural circulation.

The condensing section pipe wall 11, the heat insulation section pipe wall 12 and the evaporation section pipe wall 13 of the heat pipe are made of Inconel-690 alloy or C71500 alloy, the Inconel-690 alloy has excellent capability of resisting intergranular corrosion and intergranular stress corrosion cracking, and the high-purity C71500 alloy can resist cold deformation, thermal deformation and corrosion and is more suitable for small-sized marine reactor heat exchangers.

The outer surfaces of the condensation section pipe wall 11, the evaporation section pipe wall 13 and the heat insulation sleeve 9 of the heat pipe are coated with nano coatings, and the nano coatings are made of SiO ₂ Or Al, ti or V, the nano coating forms a super-hydrophobic surface, and the contact angle theta of the super-hydrophobic surface>150 degrees and has the function of preventing particle deposition.

The heat pipe wick 10 is an omega-shaped wick, the structural design of the wick imitates the shape of a lotus leaf, namely, the convex part inside the heat pipe is in an arc shape, the thickness of the thinnest part is 2mm-4mm, the thickness of the thickest part is 7mm-10mm, the curvature radius range of the convex part is 2.5 mm-3.5 mm, the curvature radius range of the groove part is 1.5 mm-2mm, and the distance between two adjacent convex parts is 7mm-9mm, which is shown in figure 4.

The outer surfaces of the pipe wall 11 of the condensation section and the pipe wall 13 of the evaporation section of the heat pipe are provided with the folds 6 which are uniformly arranged in a thread shape. The shape of the folds 6 is designed according to the folding structure of an African trunk, the folds are irregular waves, referring to figure 5, the height H of the folds 6 is 3mm to 4mm, and the width L of the bottom edge is 4mm to 6mm. The height of the rubber is 3mm to 4mm, and the width of the bottom is 4mm to 6mm. The folds 6 are formed by connecting a plurality of arc-shaped bulges with different curvature radiuses and a plurality of arc-shaped grooves with different curvature radiuses, the range of the curvature radius of the maximum arc-shaped bulge is 0.35mm to 0.5mm, the range of the curvature radius of the minimum arc-shaped bulge is 0.25mm to 0.4mm, the range of the curvature radius of the maximum arc-shaped groove is 0.3mm to 0.4mm, and the range of the curvature radius of the minimum arc-shaped groove is 0.2mm to 0.3mm.

In one embodiment, pleats 6 are symmetrical in configuration, with the top of pleats 6 being an arcuate bulge. The bulges and the grooves of the folds 6 are circular arcs, and the circular arcs of the bulges and the grooves are in smooth transition. The radius of the convex part on one side of the fold 6 and the arc of the groove is respectively as follows: r1, R2, R3, R4, R5, R6, R7, R8, R1~ R8's size is respectively: 0.2mm to 0.3mm,0.15mm to 0.25mm,0.12mm to 0.2mm,0.1mm to 0.15mm,0.3mm to 0.6mm,0.25mm to 0.5mm,0.15mm to 0.2mm,0.2mm to 0.3mm, see FIG. 6.

The tip of the fold 6 is provided with a bionic pore 5 corresponding to each protrusion on the liquid absorption core 10, the shape of the bionic pore 5 is designed according to the structure of a butterfly vein guide hole on the human skull, the length of the bionic pore 5 is 7mm to 10mm, the diameter of the tip part is 0.5mm to 1mm, and the diameter range of the root part is 2mm to 3mm. Meanwhile, the inner surface parts of the condensation section pipe wall 11 and the evaporation section pipe wall 13 around the bionic fine hole 5 are provided with water-drop-shaped bulges, the water-drop-shaped bulges extend into the liquid absorption core 10, and the water-drop-shaped bulges wrap the lower end of the bionic fine hole 5.

In one embodiment, the minimum curvature radius of the water-drop-shaped bulge is 0.6mm to 1.5mm, and the maximum curvature radius is 1mm to 2mm, as shown in the specific figure 5.

In the heat pipe wall surface fold concave part, as shown in fig. 4, the heat conduction between the liquid absorbing core 10 and the pipe wall 11 is uneven, but compared with the fold convex part shown in fig. 3, the pipe wall is thinner, the heat loss in the heat conduction process is small, and the heat conduction in the axial direction of the pipe wall is relatively even.

The application relates to a bionic enhanced heat transfer heat pipe, which has the working principle that: the steam runs to the condensation section 2 to emit heat and then is condensed into liquid working medium, the liquid working medium in the condensation section 2 flows back to the evaporation section 4 under the action of capillary driving force generated by the liquid absorption core 10, new circulation is started, circulation is continued, so that heat is efficiently transferred from the evaporation section 4 to the condensation section 2, external heat is absorbed by the low-temperature evaporation section 4, and internal heat is discharged out of the pipe by the condensation section 2.

The foregoing is illustrative of the embodiments of the present application and the scope of protection is defined by the claims and their equivalents.

Claims (10)

1. A bionic enhanced heat transfer heat pipe comprises a pipe wall, a liquid absorption core and a working medium which is filled in the pipe body and circularly flows in the pipe body, wherein the liquid absorption core is arranged on the inner side of the pipe wall, and the heat pipe comprises a condensation section, an evaporation section and a heat insulation section positioned between the condensation section and the evaporation section; the method is characterized in that: the outer wall surfaces of the condensation section and the evaporation section are provided with protrusions in a threaded or annular distribution; the surface of the protrusion is a bionic surface which is wavy; bionic pores extending inwards from the top of the protrusion are arranged on the bionic surface along the circumferential direction of the heat pipe, and the bionic pores are gradually changed holes with the pore diameters gradually reduced from top to bottom.

2. The bionic enhanced heat transfer heat pipe of claim 1, wherein: the bionic surface is formed by connecting a plurality of arc-shaped protrusions with different curvature radiuses and a plurality of arc-shaped grooves with different curvature radiuses, the range of the curvature radius of the maximum arc-shaped protrusion is 0.35mm to 0.5mm, the range of the curvature radius of the minimum arc-shaped protrusion is 0.25mm to 0.4mm, the range of the curvature radius of the maximum arc-shaped groove is 0.3mm to 0.4mm, and the range of the curvature radius of the minimum arc-shaped groove is 0.2mm to 0.3mm.

3. The bionic enhanced heat transfer heat pipe of claim 1, wherein: the height of the bionic surface is 3 mm-4 mm, and the width of the bottom edge of the protrusion is 4 mm-6 mm.

4. The bionic enhanced heat transfer pipe according to any one of claims 1 to 3, wherein: the liquid suction core is an omega-shaped liquid suction core, and the convex part of the omega-shaped liquid suction core facing the inside of the heat pipe is in a circular arc shape.

5. The bionic enhanced heat transfer heat pipe of claim 4, wherein: the thickness of the thinnest part of the omega-shaped liquid absorption core is 2mm-4mm, the thickness of the thickest part is 7mm-10mm, the curvature radius range of the bulge is 2.5 mm-3.5 mm, the curvature radius range of the groove is 1.5 mm-2mm, and the distance between two adjacent bulges is 7mm-9mm.

6. The bionic enhanced heat transfer heat pipe of claim 3, wherein: the bionic pores extend inwards to the inner part of the convex part of the liquid absorption core; the shape of the bionic pore is conical, the length of the bionic pore is 7 mm-10mm, the diameter range of the tip of the bionic pore is 0.5 mm-1mm, and the diameter range of the root of the bionic pore is 2mm-3mm.

7. The bionic enhanced heat transfer heat pipe of claim 6, wherein: the inner surface parts of the condensation section pipe wall and the evaporation section pipe wall around the bionic fine holes are provided with water-drop-shaped bulges which extend into the liquid suction core,

the minimum curvature radius of the concave part is 0.6 mm-1.5 mm, and the maximum curvature radius is 1mm-2mm.

8. The bionic enhanced heat transfer heat pipe of claim 1, wherein: and arranging a heat insulation sleeve on the heat insulation section of the heat pipe.

9. The bionic enhanced heat transfer heat pipe of claim 8, wherein: the thickness of the heat insulation sleeve is 3mm to 7mm; the thickness of the pipe wall is 4mm to 8mm; the length of the heat insulation section is 200mm to 400mm; the length of the evaporation section is 300mm to 600mm; the length of the condensation section is 200mm to 400mm.

10. The bionic enhanced heat transfer heat pipe of claim 1, wherein: the outer surfaces of the condensation section and the evaporation section are super-hydrophobic surfaces.

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