CN110822962A - Design method for fin distance of loop heat pipe - Google Patents
Design method for fin distance of loop heat pipe Download PDFInfo
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- CN110822962A CN110822962A CN201911219227.4A CN201911219227A CN110822962A CN 110822962 A CN110822962 A CN 110822962A CN 201911219227 A CN201911219227 A CN 201911219227A CN 110822962 A CN110822962 A CN 110822962A
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- 238000000034 method Methods 0.000 title claims abstract description 14
- 238000013461 design Methods 0.000 title claims description 8
- 238000010521 absorption reaction Methods 0.000 claims abstract description 10
- 230000001174 ascending effect Effects 0.000 claims description 56
- 239000003381 stabilizer Substances 0.000 claims description 47
- 230000005494 condensation Effects 0.000 claims description 35
- 238000009833 condensation Methods 0.000 claims description 35
- 238000001704 evaporation Methods 0.000 claims description 28
- 230000008020 evaporation Effects 0.000 claims description 28
- 239000012530 fluid Substances 0.000 claims description 17
- 230000000630 rising effect Effects 0.000 claims description 15
- 230000000087 stabilizing effect Effects 0.000 claims description 8
- 238000012938 design process Methods 0.000 claims 1
- 230000000694 effects Effects 0.000 abstract description 23
- 230000009467 reduction Effects 0.000 abstract description 16
- 238000012546 transfer Methods 0.000 abstract description 14
- 230000035939 shock Effects 0.000 abstract description 7
- 238000005728 strengthening Methods 0.000 abstract description 5
- 238000005520 cutting process Methods 0.000 abstract description 4
- 239000007788 liquid Substances 0.000 description 18
- 239000007789 gas Substances 0.000 description 15
- 239000012808 vapor phase Substances 0.000 description 15
- 239000007791 liquid phase Substances 0.000 description 13
- 230000008859 change Effects 0.000 description 9
- 230000001965 increasing effect Effects 0.000 description 9
- 239000012071 phase Substances 0.000 description 9
- 238000002474 experimental method Methods 0.000 description 5
- 230000008569 process Effects 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 4
- 238000013016 damping Methods 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 230000002708 enhancing effect Effects 0.000 description 3
- 238000001816 cooling Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000005855 radiation Effects 0.000 description 2
- 230000005514 two-phase flow Effects 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 238000009825 accumulation Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000000191 radiation effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 239000002918 waste heat Substances 0.000 description 1
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D15/00—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies
- F28D15/02—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes
- F28D15/0266—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes with separate evaporating and condensing chambers connected by at least one conduit; Loop-type heat pipes; with multiple or common evaporating or condensing chambers
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28F—DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION
- F28F1/00—Tubular elements; Assemblies of tubular elements
- F28F1/10—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses
- F28F1/40—Tubular elements and assemblies thereof with means for increasing heat-transfer area, e.g. with fins, with projections, with recesses the means being only inside the tubular element
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- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
Abstract
The invention provides a method for designing the fin distance of a loop heat pipe, which comprises the following steps: a plurality of fins are arranged on the same radial rod, the fins have the same shape, the distance from the central rod is S1, the spacing of the fins is J1, J1 is a function of the distance S1, namely J1= F5(S1), satisfying the following requirements: j1'<0, where J1' is the first derivative of J1. The invention provides a method for designing the space of a loop heat pipe, which can carry out noise reduction and shock absorption aiming at specific conditions by emphasizing the cutting capability near the pipe wall, thereby further realizing the noise reduction and shock absorption effects and further strengthening heat transfer.
Description
The invention relates to a divisional application of 'a loop heat pipe' on application date 2017, 08 and 03 months, application number 2017106556240.
Technical Field
The invention belongs to the field of heat pipes, and particularly relates to a heat exchange heat pipe.
Background
The heat pipe technology is a heat transfer element called a heat pipe invented by George Grover (George Grover) of national laboratory of Los Alamos (Los Alamos) in 1963, fully utilizes the heat conduction principle and the rapid heat transfer property of a phase change medium, quickly transfers the heat of a heating object to the outside of a heat source through the heat pipe, and the heat conduction capability of the heat transfer element exceeds the heat conduction capability of any known metal.
The heat pipe technology is widely applied to the industries of aerospace, military industry and the like, and since the heat pipe technology is introduced into the radiator manufacturing industry, the design idea of the traditional radiator is changed for people, the single heat radiation mode that a high-air-volume motor is used for obtaining a better heat radiation effect is avoided, the heat pipe technology is adopted for enabling the radiator to obtain a satisfactory heat exchange effect, and a new place in the heat radiation industry is opened up. At present, the heat pipe is widely applied to various heat exchange devices, including the field of nuclear power, such as the utilization of waste heat of nuclear power.
On the one hand, the heat pipe is in the evaporation process, inevitable can carry liquid to in the riser, simultaneously because the exothermic condensation of condensation end to there is liquid in making the condensation end, liquid inevitable entering riser, thereby make the fluid in the riser be vapour-liquid mixture, the heat pipe can be because the noncondensable gas of ageing production simultaneously in the operation process, noncondensable gas generally rises to the condensation end on heat pipe upper portion, the existence of noncondensable gas leads to the interior pressure increase of heat pipe condensation end, pressure makes liquid flow to in the riser. Greatly influencing the heat exchange efficiency.
On the other hand, in the section from the outlet of the ascending pipe to the condensation header, because the space of the section is suddenly enlarged, the change of the space can cause the gas to rapidly flow out and gather upwards, so the change of the space can cause the gathered vapor phase (vapor mass) to enter the condensation header from the position of the ascending pipe, the vapor mass moves rapidly upwards from the position of the connecting pipe due to the poor liquid tightness of the vapor (vapor), and the liquid at the original space position of the vapor mass pushed away from the wall surface by the vapor mass can also rapidly rebound and impact the wall surface to form an impact phenomenon. The more discontinuous the gas (vapor) liquid phase, the larger the mass of gas is gathered and the greater the impact energy. The impact phenomenon can cause larger noise vibration and mechanical impact, and damage to equipment.
The applicant has previously filed a heat pipe, such as a multi-pipe type structure, which improves the above problems, and although the above structure has been effective in solving the above problems, further improvement is required.
Aiming at the problems, the invention improves on the basis of the prior invention and provides a new heat pipe, thereby solving the problems of low heat exchange coefficient and uneven heat exchange under the condition of heat exchange of the heat pipe.
Disclosure of Invention
The present invention provides a new heat pipe to solve the above-mentioned technical problems.
In order to achieve the purpose, the technical scheme of the invention is as follows:
a loop heat pipe comprises an evaporation collecting pipe, a condensation collecting pipe, an ascending pipe and a return pipe, wherein the ascending pipe is communicated with the evaporation collecting pipe and the condensation collecting pipe, the evaporation collecting pipe is positioned at the lower part, the condensation collecting pipe is positioned at the upper part, fluid is subjected to heat absorption and evaporation in the evaporation collecting pipe, enters the condensation collecting pipe through the ascending pipe, is subjected to heat exchange in the condensation collecting pipe and then is condensed, and the condensed fluid returns to the evaporation collecting pipe through the return pipe; the flow stabilizer is characterized in that a flow stabilizer is arranged in the ascending pipe, the flow stabilizer comprises a central rod and a plurality of radial rods, the central rod is axially arranged along the center of the ascending pipe, the radial rods radially extend, a plurality of fins extending downwards from the radial rods are arranged on the radial rods, each fin is provided with a tip, and the tip faces downwards.
Preferably, the fins are triangular fins.
Preferably, a plurality of fins are arranged on the same radial rod, the fins are similar in shape, and the size of the fins is larger and larger in the radial extending direction from the central rod of the ascending pipe.
Preferably, the size of the fins increases continuously from the central rod of the ascending pipe to the radial extension direction.
I.e. the distance from the central bar is S1, the size of the finsIs C1, C1= F1(S1), satisfying the following requirements:
c1 '> 0, C1 "> 0, where C1', C1" are the first and second derivatives of C1, respectively.
Preferably, a plurality of fins are arranged on the same radial rod, and the distance between the fins is continuously reduced from the central rod of the ascending pipe to the radial extending direction. The continuous reduction amplitude of the spacing between the fins is continuously increased.
I.e. a distance S1 from the central rod, a fin pitch J1, J1= F1(S1), satisfying the following requirements:
j1 '< 0, J1 "> 0, wherein J1', J1" are the first and second derivatives of J1, respectively.
Preferably, one base of the triangle is located on the radial bar and the line connecting the vertex of the angle corresponding to the side and the midpoint of the side forms an angle of 75-135 deg. with the radial bar.
Preferably 90.
Preferably, the triangular fins are isosceles triangular fins, and the bottom edges of the isosceles triangles are located on the radial rods.
Preferably, the size of the vertex angle of the isosceles triangle is a, the length of the base of the isosceles triangle is Y, and the distance between adjacent isosceles triangles is J, then the following requirements are met:
Y/J= d-a*sin(A)3-b*sin(A)2-c tan (a); wherein sin is a trigonometric function and a, b, c, d are parameters;
0.360<a<0.365,
0.495<b<0.496,
0.084<c<0.085，
0.411<d<0.412， 4<A<33°，
0.18<Y/J<0.42。
preferably, a =0.363, b = 0.4956, c =0.0846, and d = 0.4114.
Preferably, the number of the radial rods is 5-10, and the included angles between the radial rods are equal.
Preferably, the number of radial rods is 8.
Preferably, the length of the base of the isosceles triangle is 0.02 to 0.03 times the inner diameter of the ascending tube.
Compared with the prior art, the invention has the following advantages:
1) the rod-fin type flow stabilizer is arranged in the ascending pipe, the two-phase fluid is separated into the liquid phase and the vapor phase through the rod-fin type flow stabilizer, the liquid phase is divided into small liquid clusters, the vapor phase is divided into small bubbles, the vapor phase is enabled to flow smoothly, the flow stabilizing effect is achieved, the vibration and noise reduction effect is achieved, and the heat exchange effect is improved.
2) By arranging the rod-fin type flow stabilizing device, the invention is equivalent to adding the inner fin in the ascending pipe, thereby strengthening the heat exchange and improving the heat exchange effect.
3) The invention divides the vapor-liquid two phases on the whole cross section position of the ascending pipe, avoids only dividing the inner wall surface of the ascending pipe, thereby realizing the enlargement of the contact area of the vapor-liquid interface and the vapor phase boundary layer with the cooling wall surface on the whole ascending pipe section, enhancing the disturbance, reducing the noise and the vibration and strengthening the heat transfer.
4) According to the invention, the distance between adjacent flow stabilizers, the length of the flow stabilizer, the size of the fin and other parameters are regularly changed in the height direction of the ascending pipe, so that the flow stabilizing effect is further achieved, the noise is reduced, and the heat exchange effect is improved.
5) According to the invention, the regular change of the size of parameters such as the size, the distance and the like of adjacent fins is arranged in the radial direction, so that the flow stabilizing effect is further achieved, the noise is reduced, and the heat exchange effect is improved.
6) According to the invention, the heat exchange rule caused by the change of each parameter of the rod-fin type flow stabilizer is widely researched, and the optimal relational expression of the effects of vibration reduction, noise reduction and heat transfer enhancement is realized under the condition of meeting the flow resistance.
Drawings
FIG. 1 is a schematic view of a heat pipe configuration of the present invention;
FIG. 2 is a schematic view of the internal cross-sectional structure of the riser;
FIG. 3 is a schematic view of the cross-sectional A-A structure of FIG. 2;
fig. 4 is a schematic view of a preferred isosceles triangular embodiment of the flow stabilizer of the present invention;
fig. 5 is a schematic view of the flow stabilizer dimensional parameters of the present invention.
In the figure: 1. evaporation header, 2, condensation header, 3, ascending pipe, 4, flow stabilizer, 41 center rod, 42 radial rod, 43 fin, 5, return pipe.
Detailed Description
The following detailed description of embodiments of the invention refers to the accompanying drawings.
In this document, "/" denotes division and "×", "denotes multiplication, referring to formulas, if not specifically stated.
A heat pipe as shown in fig. 1, comprising an evaporation header 1, a condensation header 2, a rising pipe 3 and a return pipe 5, wherein the rising pipe 3 is communicated with the evaporation header 1 and the condensation header 2, the evaporation header 1 is positioned at the lower part, the condensation header 2 is positioned at the upper part, the fluid is evaporated by heat absorption in the evaporation header 1, enters the condensation header 2 through the rising pipe 3, is condensed after heat exchange in the condensation header 2, and the condensed fluid returns to the evaporation header 1 through the return pipe 5; a flow stabilizer 4 is arranged in the ascending pipe 3, the flow stabilizer 4 comprises a central rod 41 arranged along the central axial direction of the ascending pipe 3 and a plurality of radial rods 42 extending along the central rod 41 in the radial direction, a plurality of fins 43 extending downwards from the radial rods 42 are arranged on the radial rods 42, and the fins 43 have tip parts which face downwards, as shown in fig. 2-4.
Compared with the prior application, the invention has the advantages that the rod-fin type flow stabilizer is arranged in the ascending pipe 3, the ascending liquid phase and the vapor phase in the two-phase fluid are separated through the tip of the rod-fin type flow stabilizer, the ascending liquid phase is divided into small liquid masses, so that the liquid phase is promoted to absorb heat quickly and further change into the vapor phase, meanwhile, the ascending vapor phase is divided into small bubbles, the complete separation of the liquid phase and the vapor phase is avoided, the liquid phase vapor phase in the ascending is promoted to flow smoothly, the flow stabilizing effect is achieved, the vibration reduction and noise reduction effects are achieved, and the heat transfer enhancement effect is achieved. Experiments show that compared with the prior application, the structure can improve the vibration and noise reduction effect by more than 15%, and can improve the heat transfer effect by more than 10%.
By arranging the rod-fin type flow stabilizing device, the invention is equivalent to adding the inner fin in the ascending pipe 3, thereby strengthening the heat exchange and improving the heat exchange effect.
The invention divides the vapor-liquid two phases at all cross section positions of the ascending pipe 3, thereby realizing the contact area of the vapor-liquid interface and the vapor phase boundary layer on the whole ascending pipe section and the cooling wall surface, enhancing disturbance, greatly reducing noise and vibration and strengthening heat transfer.
Preferably, the return pipe 5 connects the positions of both side ends of the evaporation header 1 and the condensation header 2. Therefore, the flow path of the fluid in the condensation header 2 is ensured to be long, the heat exchange time can be further prolonged, and the heat exchange efficiency is improved.
Preferably, the fins 43 are triangular fins, as shown in fig. 3-4. Because the triangular fin is provided with three tips, the tips can be fully utilized to carry out the flow stabilizing effect downwards.
The radial rod and the triangular fins extending outwards along the radial rod are arranged, so that the heat exchange area can be further increased, the heat exchange effect is improved, and due to the triangular fins, turbulence can be further increased through the triangular tips of the triangular fins similar to the needle-shaped structure, so that fluid is fully mixed, the increase and aggregation of bubbles can be further destroyed, and the heat exchange effect is improved.
Further preferably, the radial bars are rectangular, preferably square, in cross-section.
Further preferably, the radial rod is circular in cross-section.
Preferably, the engineering diameter of the radial rod is 0.21 to 0.42 times, preferably 0.32 times the engineering diameter of the central rod.
Preferably, the radial rod is a rod-shaped object and extends from the center of the circle to the inner wall of the condensation pipe along the radial direction.
Preferably, a plurality of triangular fins are provided on each radial rod, said plurality of triangular fins being of similar shape. Namely, the three mutually corresponding internal angles of different triangular fins are the same.
Preferably, the radial rods are round rods with a diameter of 0.7-1.1 mm, preferably 0.8 mm.
Preferably, the fins extend downwardly from the centerline of the round bar. The fins are of a flat plate structure. The planar structure extension surface passes through the center line of the central rod, and the planar structure extension surface passes through the center line of the radial rod.
Preferably, as shown in fig. 3 and 4, a plurality of fins 43 are provided on the same radial rod, the fins 43 are of similar shape (i.e., the fins have the same shape), and the size of the fins on the same radial rod increases in the radial direction from the central rod 41 of the ascending tube 3. I.e. at a distance S1 from the central bar 41 (i.e. from the riser central axis), and the fin size C1, C1 being a function of the distance S1, i.e. C1= F4(S1), satisfying the following requirements:
c1 '> 0, where C1' is the first derivative of C1.
Because the heat exchange mainly occurs on the pipe wall of the ascending pipe, the capacity of cutting a vapor phase and a liquid phase near the pipe wall is enhanced by increasing the size of the fins 43 on the pipe wall of the ascending pipe, and the noise and shock absorption can be pertinently carried out aiming at specific conditions by emphasizing the cutting capacity near the pipe wall, so that the noise and shock absorption effect is further realized, and the heat transfer can be further enhanced.
Further preferably, the size of the fins on the same radial rod increases continuously from the central rod of the riser to the radial extension direction. I.e., C1 "> 0, where C1" is the second derivative of C1, respectively.
Numerical simulation and experimental research show that the change of the increase amplitude can further realize noise reduction and shock absorption, and the effect can be improved by nearly 9%.
Preferably, a plurality of fins 43 are provided on the same radial rod 42, and the spacing between the fins 43 is continuously reduced in the radial direction extending from the central rod 41 of the ascending tube 3. The continuous reduction amplitude of the spacing between the fins is continuously increased.
I.e. from the central rodDistance S1, fin pitch J1, J1= F5(S1), satisfying the following requirements:
j1 '< 0, J1 "> 0, wherein J1', J1" are the first and second derivatives of J1, respectively.
The specific principle is the same as the above. Because the heat exchange mainly occurs on the pipe wall of the ascending pipe, the capability of cutting vapor phase and liquid phase near the pipe wall is enhanced by increasing the distribution of the fins 43 on the pipe wall of the ascending pipe, and the noise reduction and shock absorption effects are further realized by enhancing the noise reduction and shock absorption near the pipe wall, and the heat transfer can be further enhanced.
Preferably, one base of the triangle is located on the radial bar 42, and the line connecting the vertex of the angle corresponding to this side and the midpoint of this side forms an angle of 75-135 ° with the radial bar. Mainly through the setting of the angle, the tip of the fin can be cut into vapor and liquid phases to the maximum extent, so that the effect of the invention is further improved.
Preferably, the angle formed by the radial rod and the line connecting the vertex of the corresponding angle of the edge and the midpoint of the edge is 90 °.
Preferably, as shown in fig. 4, the triangular fins are isosceles triangular fins, and the bottom sides of the isosceles triangles are located on the radial rods.
Analysis and experiments show that the spacing between the fins 43 cannot be too large, the damping and noise reduction effect is poor if the spacing is too large, the resistance is too large if the spacing is too small, and the resistance is too small if the spacing is too small, and similarly, the height of the fins cannot be too large or too small, and the damping and noise reduction effect is poor or the resistance is too large, so that the damping and noise reduction can be optimized under the condition that normal flow resistance (the total pressure bearing is less than 2.5Mpa or the on-way resistance of a single ascending pipe is less than or equal to 5 Pa/M) is preferentially met through a large number of experiments, and the optimal relation of each parameter is arranged.
The size of the vertex angle of the isosceles triangle is A, the length of the bottom edge of the isosceles triangle is Y, and the distance between the adjacent isosceles triangles is J, so that the following requirements are met:
Y/J= d-a*sin(A)3-b*sin(A)2-ctan (a); wherein sin is a trigonometric function and a, b, c, d are parameters;
0.360<a<0.365,
0.495<b<0.496,
0.084<c<0.085，
0.411<d<0.412， 4<A<33°，
0.18<Y/J<0.42。
wherein the distance J between adjacent isosceles triangles is the distance between the midpoints of the bases of adjacent triangles.
Preferably, a =0.363, b = 0.4956, c =0.0846, and d = 0.4114.
Preferably, 5< a <30 °.
Preferably, the number of the radial rods is 5-10, and the included angles between the radial rods are equal.
Preferably, the number of radial rods is 8.
Preferably, the length of the base of the isosceles triangle is 0.02 to 0.03 times the inner diameter of the ascending tube.
Preferably, the condensing header 2 is internally provided with heat exchange tubes, and the fluid in the heat exchange tubes exchanges heat with the steam in the condensing header 2.
Preferably, the rising pipes 3 and the evaporation header 1 are heat absorbing portions.
Preferably, a plurality of flow stabilizers 4 are arranged in the rising pipe 3 along the flowing direction (i.e. the height direction of fig. 3) of the fluid in the rising pipe 3, and the distance between the adjacent flow stabilizers is shorter from the inlet of the rising pipe to the outlet of the rising pipe. Setting the distance from the inlet of the ascending pipe to be H, and the distance between adjacent flow stabilizers to be S, S = F1(H) I.e. S is a function of the height H as a variable, S' is the first derivative of S, satisfying the following requirements:
S’<0;
the main reason is that the gas in the ascending pipe carries liquid in the ascending process, the ascending pipe is continuously heated in the ascending process, so that more and more gas in gas-liquid two-phase flow is caused, the gas phase in the gas-liquid two-phase flow is increased, the heat exchange capacity in the ascending pipe is relatively weakened along with the increase of the gas phase, and the vibration and the noise are also continuously increased along with the increase of the gas phase. The distance between adjacent flow stabilizers needs to be set shorter and shorter.
In addition, in the section from the outlet of the ascending pipe to the condensation header, because the space of the section is suddenly enlarged, the change of the space can cause the gas to rapidly flow out and gather upwards, so the change of the space can cause the gathered vapor phase (vapor mass) to enter the condensation header from the position of the ascending pipe, the vapor mass moves rapidly upwards from the position of the connecting pipe due to the poor liquid tightness of the vapor (vapor), and the liquid at the original space position of the vapor mass pushed away from the wall surface by the vapor mass can also rapidly rebound and impact the wall surface, so the impact phenomenon is formed. The more discontinuous the gas (vapor) liquid phase, the larger the gas mass accumulation and the larger the water hammer energy. The impact phenomenon can cause larger noise vibration and mechanical impact, and damage to equipment. Therefore, in order to avoid the phenomenon, the distance between adjacent flow stabilizers is set to be shorter and shorter, so that the gas phase and the liquid phase are separated continuously in the fluid conveying process, and vibration and noise are reduced to the maximum extent.
Through the experiment discovery, through foretell setting, both can reduce vibrations and noise to the at utmost, can improve the heat transfer effect simultaneously.
It is further preferred that the distance between adjacent flow stabilizers increases progressively from the inlet of the rising pipe 3 to the outlet of the rising pipe 3, being shorter and shorter. I.e. S "is the second derivative of S, the following requirements are met:
S”>0;
through the experiment, the vibration and the noise of about 9 percent can be further reduced, and the heat exchange effect of about 7 percent is improved.
Preferably, the length of each flow stabilizer 4 remains constant.
Preferably, other parameters of the flow stabilizer (e.g., length, tube diameter, etc.) are kept constant except for the distance between adjacent flow stabilizers 4.
Preferably, a plurality of flow stabilizers 4 are provided in the rising pipe 3 along the height direction of the rising pipe 3, and the height of the fins (i.e., the fins) of the flow stabilizers 4 is set from the inlet of the rising pipe 3 to the outlet of the rising pipe 3The distance of the tip apex of the blade from the radial stem on which the fin is located) is longer and longer. I.e. the height of the fin of the flow stabilizer is C, C = F2(H) And C' is the first derivative of C, and meets the following requirements:
C’>0;
it is further preferred that the fin height of the flow stabilizer increases progressively from the inlet of the riser to the outlet of the riser. I.e., C "is the second derivative of C, the following requirement is satisfied:
C”>0;
for example, the distance between adjacent flow stabilizers may vary equally.
Preferably, the distance between adjacent flow stabilizers remains constant.
Preferably, other parameters of the flow stabilizer (e.g., adjacent spacing, tube diameter, etc.) are maintained, other than the length of the flow stabilizer.
Preferably, a plurality of flow stabilizers are arranged in the ascending tube 3 along the height direction of the ascending tube 3, and the distribution density of the fins in different flow stabilizers 4 is increased from the inlet of the ascending tube 3 to the outlet of the ascending tube 3. That is, the fin distribution density of the flow stabilizer is M, M = F3(H) M' is the first derivative of M, satisfying the following requirements:
M’>0;
preferably, the diameter of the tube of the flow stabilizer increases from the inlet of the riser to the outlet of the riser with a decreasing magnitude. Namely, it is
M' is the second derivative of M, and meets the following requirements:
M ”>0。
for example, the distance between adjacent flow stabilizers may vary equally.
Preferably, the length of the flow stabilizers and the distance between adjacent flow stabilizers remain constant.
Preferably, other parameters of the flow stabilizer (e.g., length, distance between adjacent flow stabilizers, etc.) are maintained constant, except for the diameter of the tube of the flow stabilizer.
The distance between adjacent flow stabilizers is S, the inner diameter of the ascending pipe is W, and the distance S between the flow stabilizers is the distance between the central axes of the adjacent radial rods of the adjacent flow stabilizers.
34mm<W<58mm；
50mm<S<80mm。
Preferably, the riser length L is between 3000-5500 mm. More preferably, 3500-4500 mm.
Further preferred, 40mm < W <50 mm;
55mm<S<60mm。
preferably, S is greater than 1.4 times the height of the fin.
Preferably, the height of the fins is the average of the two largest fin heights on adjacent radial bars. I.e. the weighted average of the highest height of the fins on the first radial bars and the highest height of the fins on the second radial bars.
For other parameters, such as the wall thickness of the pipe and the wall thickness of the shell, the parameters are set according to normal standards.
Preferably, the fluid within the heat pipe is water.
Preferably, the pipe diameter of the evaporation header 1 is smaller than that of the condensation header 2.
The evaporation header has an internal diameter of R1 and the condensation header has an internal diameter of R2, preferably 0.45< R1/R2< 0.88.
Through the arrangement, heat transfer can be further enhanced, and the heat exchange efficiency can be improved by more than 7%.
Although the present invention has been described with reference to the preferred embodiments, it is not limited thereto. Various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (6)
1. A design method for the fin distance of a loop heat pipe comprises an evaporation collecting pipe, a condensation collecting pipe, an ascending pipe and a return pipe, wherein the ascending pipe is communicated with the evaporation collecting pipe and the condensation collecting pipe, the evaporation collecting pipe is positioned at the lower part, the condensation collecting pipe is positioned at the upper part, and fluid absorbs heat in the evaporation collecting pipe and evaporatesThe condensed fluid enters a condensation collecting pipe through a rising pipe, is condensed after heat exchange in the condensation collecting pipe, and returns to an evaporation collecting pipe through a return pipe; the flow stabilizing device is arranged in the ascending pipe and comprises a central rod arranged in the central axial direction of the ascending pipe and a plurality of radial rods extending radially along the central rod, a plurality of fins extending downwards from the radial rods are arranged on the radial rods, each fin is provided with a tip part, the tip part faces downwards, and the fin design method comprises the following steps: a plurality of fins are arranged on the same radial rod, the fins have the same shape, the distance from the central rod is S1, the spacing of the fins is J1, J1 is a function of the distance S1, namely J1= F5(S1), satisfying the following requirements:
j1 '< 0, where J1' is the first derivative of J1.
2. The design method of claim 1, wherein J1 "> 0, where J1" is the second derivative of J1.
3. The design method of claim 1, wherein the fins are triangular fins.
4. A design process according to claim 3, wherein one base of the triangle is located on the radial rod and the line connecting the vertex of the angle corresponding to the edge and the midpoint of the edge forms an angle of 75-135 ° with the radial rod.
5. The design method as claimed in claim 3, wherein said triangular fins are isosceles triangular fins, the base of said isosceles triangle being located on the radial bar.
6. A loop heat pipe comprises an evaporation header, a condensation header, an ascending pipe and a return pipe, wherein the ascending pipe is communicated with the evaporation header and the condensation header, the evaporation header is positioned at the lower part, the condensation header is positioned at the upper part, fluid is subjected to heat absorption and evaporation in the evaporation header, enters the condensation header through the ascending pipe, is subjected to heat exchange in the condensation header and then is condensed, and the condensed fluid returns to the evaporation header through the return pipe; set up current stabilizer in the tedge, current stabilizer includes that the central axial along the tedge sets up well core rod and along many radial poles of well core rod to radial extension, set up many fins from radial pole downwardly extending on the radial pole, the fin has sharp portion, sharp portion is down.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911219227.4A CN110822962B (en) | 2017-08-03 | 2017-08-03 | Design method for fin distance of loop heat pipe |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911219227.4A CN110822962B (en) | 2017-08-03 | 2017-08-03 | Design method for fin distance of loop heat pipe |
| CN201710655624.0A CN109387104B (en) | 2017-08-03 | 2017-08-03 | Loop heat pipe |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710655624.0A Division CN109387104B (en) | 2017-08-03 | 2017-08-03 | Loop heat pipe |
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| Publication Number | Publication Date |
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| CN110822962A true CN110822962A (en) | 2020-02-21 |
| CN110822962B CN110822962B (en) | 2021-05-07 |
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| CN201911219227.4A Expired - Fee Related CN110822962B (en) | 2017-08-03 | 2017-08-03 | Design method for fin distance of loop heat pipe |
| CN202010015017.XA Pending CN111174612A (en) | 2017-08-03 | 2017-08-03 | Design method for distance between current stabilizers |
| CN201710655624.0A Expired - Fee Related CN109387104B (en) | 2017-08-03 | 2017-08-03 | Loop heat pipe |
| CN202010014448.4A Expired - Fee Related CN111189341B (en) | 2017-08-03 | 2017-08-03 | Design method for fin height of flow stabilizer |
| CN202010014439.5A Expired - Fee Related CN111174611B (en) | 2017-08-03 | 2017-08-03 | Design method for fin density in height direction of flow stabilizer |
| CN201911219228.9A Expired - Fee Related CN110822963B (en) | 2017-08-03 | 2017-08-03 | Design method for size of loop heat pipe fin |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202010015017.XA Pending CN111174612A (en) | 2017-08-03 | 2017-08-03 | Design method for distance between current stabilizers |
| CN201710655624.0A Expired - Fee Related CN109387104B (en) | 2017-08-03 | 2017-08-03 | Loop heat pipe |
| CN202010014448.4A Expired - Fee Related CN111189341B (en) | 2017-08-03 | 2017-08-03 | Design method for fin height of flow stabilizer |
| CN202010014439.5A Expired - Fee Related CN111174611B (en) | 2017-08-03 | 2017-08-03 | Design method for fin density in height direction of flow stabilizer |
| CN201911219228.9A Expired - Fee Related CN110822963B (en) | 2017-08-03 | 2017-08-03 | Design method for size of loop heat pipe fin |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111998704B (en) * | 2019-05-27 | 2022-02-01 | 山东大学 | Vibration method of mirror-symmetric loop heat pipe |
| CN111998705B (en) * | 2019-05-27 | 2022-03-29 | 山东大学 | Rotationally symmetric circulating heat source loop heat pipe |
| CN112833692B (en) * | 2021-01-08 | 2022-05-24 | 苏州好嗨哟智能科技有限公司 | Radian-variable straight-plate uniform-temperature loop heat pipe |
| CN112833690B (en) * | 2021-01-08 | 2022-05-27 | 东莞市立敏达电子科技有限公司 | Circular arc temperature-equalizing loop heat pipe with variable downstream angle |
| CN112833689A (en) * | 2021-01-08 | 2021-05-25 | 青岛宝润科技有限公司 | Circular arc temperature-equalizing loop heat pipe with variable upstream angle |
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| CN106839843A (en) * | 2017-01-16 | 2017-06-13 | 奇鋐科技股份有限公司 | Loop heat pipe structure |
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- 2017-08-03 CN CN201911219227.4A patent/CN110822962B/en not_active Expired - Fee Related
- 2017-08-03 CN CN202010015017.XA patent/CN111174612A/en active Pending
- 2017-08-03 CN CN201710655624.0A patent/CN109387104B/en not_active Expired - Fee Related
- 2017-08-03 CN CN202010014448.4A patent/CN111189341B/en not_active Expired - Fee Related
- 2017-08-03 CN CN202010014439.5A patent/CN111174611B/en not_active Expired - Fee Related
- 2017-08-03 CN CN201911219228.9A patent/CN110822963B/en not_active Expired - Fee Related
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Also Published As
| Publication number | Publication date |
|---|---|
| CN111189341B (en) | 2021-03-26 |
| CN111174611A (en) | 2020-05-19 |
| CN111174612A (en) | 2020-05-19 |
| CN111189341A (en) | 2020-05-22 |
| CN110822962B (en) | 2021-05-07 |
| CN110822963B (en) | 2021-05-07 |
| CN110822963A (en) | 2020-02-21 |
| CN109387104A (en) | 2019-02-26 |
| CN109387104B (en) | 2020-04-14 |
| CN111174611B (en) | 2021-03-26 |
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