Reinforcing rib structure without flow channel blocking

Abstract

The invention relates to a reinforcing rib structure without flow channel blocking in a heat pipe, and belongs to the field of efficient structure heat transfer. The reinforcing rib structure without flow channel blocking in the heat pipe comprises a top plate (1), reinforcing ribs (2), a porous inner wall structure (3), an outer wall structure (4) and a bottom plate (5). Wherein the reinforcing ribs (2) are composed of millimeter-scale porous structures (7) and comprise macroscopic centimeter-scale porous structures (8), the porous inner wall structures (3) comprise hundred-micron-scale mesoscopic pore structures, and capillary channel structures (6) are arranged on the inner surfaces of the top plate (1) and the bottom plate (5). The top plate (1), the bottom plate (5) and the outer wall structure (4) form a closed airtight structure, mesoscopic pores in the porous inner wall structure (3) and capillary channel structures (6) on the inner surfaces of the top plate (1) and the bottom plate (5) form a liquid working medium backflow channel, and millimeter-scale porous structures (7) in the reinforcing ribs (2), macroscopic centimeter-scale pores (8) and other cavities in the heat pipe closed structure are gaseous working medium circulation channels.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of reinforcing rib structure without flow channel block in heat pipe, belong to high-efficiency structure heat transfer field. BACKGROUND

[0002] Heat pipe is a kind of high-efficiency heat transfer component based on internal working medium phase change cycle, solid or liquid working medium is vaporized in heat end and flows to cold end under the pressure difference of gaseous working medium, and condenses in wall surface heat release along with temperature and saturated gaseous working medium pressure drop liquefaction, based on this process, phase change heat absorption and release and flow mass transfer realize efficient heat exchange of cold and hot end. At the same time, working medium is liquefied in cold end wall surface and realizes backflow to hot end under the action of capillary driving force, so as to realize closed cycle of internal working medium of heat pipe. It can be seen that the efficient heat transfer of heat pipe depends on the rapid flow of gaseous and liquid working medium in hot end and cold end.

[0003] Heat pipe bears internal saturated gaseous working medium pressure, external environmental pressure, high temperature environment and other mechanical load in working state, and needs to meet the requirements of rigidity and strength to maintain structural integrity, and often needs to arrange reinforcing rib and other reinforcing load capacity inside.

[0004] At present, in order to ensure the flow of working medium, continuous longitudinal reinforcing rib parallel to the flow direction of working medium is designed, or cross reinforcing rib structure is designed, but continuous longitudinal reinforcing rib hinders the transverse flow of working medium, and cross reinforcing rib structure ensures the flow of working medium but greatly weakens the mechanical load bearing effect of rib, so in the scene where transverse reinforcing rib needs to be arranged in structural force and thermal load environment, or there is transverse heat flow gradient in heat pipe service environment, traditional solid reinforcing rib will significantly cause the decline of heat pipe heat transfer function, even cause transverse heat and mass transfer failure, so that the structure uniformity decreases, causes structure overtemperature or thermal structure rigidity, strength deficiency and failure. SUMMARY

[0005] The problem solved by the present application is to provide a kind of reinforcing rib structure without flow channel block in heat pipe, considering the flow requirements of gaseous and liquid working medium in heat pipe cavity and channel, through the interface design of reinforcing rib and top plate and bottom plate capillary channel and the design of porous inner wall capillary structure, meet the flow requirements of liquid working medium, through the millimeter level porous design of reinforcing rib and the centimeter level macro channel design meet the flow requirements of gaseous working medium.

[0006] The technical solution of this invention is: a reinforcing rib structure without flow channel obstruction inside a heat pipe, comprising: a top plate, reinforcing ribs, a porous inner wall structure, an outer wall structure, and a bottom plate; wherein, millimeter-scale porous structures are provided inside the reinforcing ribs, macroscopic-sized holes are provided on the reinforcing ribs, and microscopic pores are provided on the porous inner wall structure, the pores being on the order of hundreds of micrometers; capillary channel structures are provided on the inner surfaces of the top plate and the bottom plate; the top plate, the bottom plate, and the outer wall structure form a closed and airtight structure, the microscopic pores and capillary channel structures in the porous inner wall structure form a liquid working fluid return channel, and the millimeter-scale porous structures, macroscopic-scale holes, and other cavities inside the closed structure of the heat pipe in the reinforcing ribs are all gaseous working fluid flow channels, and the flow directions of the liquid and gaseous working fluids are perpendicular to the reinforcing ribs.

[0007] Preferably, the width w of the capillary channel structure is on the order of hundreds of micrometers.

[0008] Preferably, the width of the capillary channel structure is less than 300 micrometers.

[0009] Preferably, the characteristic scale of the micropores is d. m , less than 300 micrometers.

[0010] Preferably, the millimeter-scale porous structure characteristic scale of the reinforcing rib is d. j The diameter is not less than 2 mm and the porosity is not less than 50%.

[0011] Preferably, the upper surface of the porous reinforcing rib is connected to the groove-free portion of the lower surface of the top plate, and the lower surface of the porous reinforcing rib is connected to the groove-free portion of the upper surface of the bottom plate, ensuring the continuity of the capillary channels.

[0012] Preferably, the characteristic dimension of the macroscopic hole reserved for the reinforcing rib is d. M The value is on the order of centimeters; the number of macroscopic pores is n, and the sum of the ventilation areas of the macroscopic pores is not less than 50% of the longitudinal cross-sectional area of ​​the reinforcing rib.

[0013] Preferably, the top plate, reinforcing ribs, porous inner wall structure, outer wall structure, and bottom plate are made of nickel-based high-temperature alloy or refractory metal alloy, and are integrally formed by welding after individual component processing or by 3D printing additive manufacturing process.

[0014] Preferably, the millimeter-scale porous structure inside the reinforcing rib is selected from random porous structure, periodic unit cell structure or porous structure with gradient pore size variation.

[0015] Preferably, the macroscopic holes on the reinforcing ribs are round holes, elliptical holes, or rhomboid holes.

[0016] Compared with the prior art, the present invention has at least the following beneficial effects: This invention achieves structural load-bearing capacity and unobstructed flow channels for both gaseous and liquid working fluids through an integrated macroscopic and microscopic porous structure design of the internal reinforcing ribs. This design surpasses traditional solid reinforcing rib structures by reducing the obstruction of flow channels for both gaseous and liquid working fluids, resulting in superior mass transfer efficiency and higher heat transfer capacity. This invention presents a method for designing a heat pipe with a non-obstructive reinforcing rib structure, characterized by high heat and mass transfer efficiency, strong load-bearing capacity, integrated structural function, and wide applicability.

[0017] The reinforcing rib structure without flow channel obstruction provided in this embodiment of the invention is connected to the inner surfaces of the top plate and bottom plate only in the parts without channels. That is, the channels are not blocked by the reinforcing ribs and remain unobstructed. The liquid working fluid reflux efficiency is high, which is better than the traditional solid reinforcing rib design scheme that only considers the structural load-bearing capacity and does not consider the flow channel obstruction. The stiffening rib structure without flow channel obstruction provided in this embodiment of the invention maintains axial continuity on a macroscopic scale, which is superior to the traditional truncated cross-shaped short rib scheme and can improve structural stiffness. The porous reinforcing rib structure provided in this embodiment of the invention has millimeter-level pores, which allows gaseous working fluid to pass through. This is superior to the traditional solid reinforcing rib structure, enhances the flow capacity of working fluid on both sides of the reinforcing rib, and increases the flow path of gaseous working fluid. The porous reinforcing rib structure provided in this embodiment of the invention features macroscopic pores in a large area, allowing gaseous working fluid to flow through the pores of the reinforcing rib structure. This is superior to a solid, non-porous reinforcing rib structure, enhancing the flow capacity of gaseous working fluid between the two sides of the reinforcing rib inside the heat pipe cavity and improving the ability of gaseous working fluid to be transferred from the hot end to the cold end. The porous reinforcing rib structure provided in this invention embodiment, based on millimeter-level porous structure and stiffness and strength design of reinforcing rib thickness, is superior to solid reinforcing rib structure, can effectively reduce stress concentration at reinforcing rib location, and enhance the local load-bearing capacity of structure; The porous reinforcing rib structure provided in this invention is designed with macroscopic and microscopic pore structures based on the flow function of gaseous and liquid working fluids and the structural load-bearing function. It is superior to the solid reinforcing rib structure that only considers load-bearing enhancement. The porous reinforcing rib of this invention realizes the integrated optimization design of structural function with no flow channel obstruction and stiffness and strength, which enhances heat and mass transfer and structural load-bearing capacity. It has the characteristics of high heat and mass transfer efficiency, strong load-bearing capacity, integrated structural function, and wide applicability. Attached Figure Description

[0018] Figure 1 This invention relates to a heat pipe structure containing reinforcing ribs without flow channel blocking. Figure 2 This is an internal diagram of the reinforcing rib structure inside the heat pipe without flow channel obstruction; Figure 3 It consists of a top slab and a bottom slab structure; Figure 4For reinforcing ribs and macroscopic openings; Figure 5 To reinforce the millimeter-scale porous structure. Detailed Implementation

[0019] The following example illustrates the design process of a shunting rudder shaft: This invention provides a reinforcing rib structure for heat pipes that does not obstruct the flow channels of gaseous or liquid working fluids, supporting and realizing an integrated high-temperature heat pipe. For example... Figure 1 , 2 As shown in Figure 3, the structure includes: a top plate 1, reinforcing ribs 2, a porous inner wall structure 3, an outer wall structure 4, and a bottom plate 5. The reinforcing ribs 2 and the porous inner wall structure 3 are composed of millimeter-scale porous structures 7, and the inner surfaces of the top plate 1 and the bottom plate 5 have capillary channel structures 6. The top plate 1, bottom plate 5, and outer wall structure 4 form a closed, airtight structure. The fine pores and capillary channel structures 6 in the porous inner wall structure 3 form a liquid working fluid reflux channel. The millimeter-scale porous structures 7, macroscopic pores 8, and other cavities inside the heat pipe closed structure in the reinforcing ribs 2 are all gaseous working fluid flow channels. The flow directions of the liquid and gaseous working fluids are as follows: Figure 2 As indicated by the middle arrow.

[0020] The upper surface of the porous reinforcing rib 2 is connected to the ungrooved portion of the lower surface of the top plate 1, and the lower surface of the porous reinforcing rib 2 is connected to the ungrooved portion of the upper surface of the bottom plate 5, ensuring the continuity of the capillary channels 6.

[0021] In a preferred embodiment of the present invention, the top plate 1, reinforcing rib 2, porous inner wall structure 3, outer wall structure 4, and bottom plate 5 are made of nickel-based high-temperature alloy or refractory metal alloy, and are integrally formed by welding or 3D printing additive manufacturing processes after individual component processing. The fine pore structure in the porous inner wall structure and reinforcing rib structure can be achieved through additive manufacturing processes and welded to the top plate and bottom plate.

[0022] In a preferred embodiment of this invention, the width w of the capillary channels on the inner walls of the top plate 1 and the bottom plate 5 is on the order of hundreds of micrometers, which meets the reflux requirements driven by capillary force of the liquid working fluid. The channel spacing is optimized according to the service environment. A size of less than 300 micrometers is recommended to meet the capillary driving force requirements of the liquid working fluid, allowing the liquid working fluid to flow inside the reinforcing ribs under capillary force.

[0023] In a preferred embodiment of the present invention, the porous capillary structure within the porous inner wall structure 3 refers to the microscopic pore characteristic scale d. m The size is on the order of hundreds of micrometers, meeting the requirements for reflux driven by capillary force of liquid working fluid in service environments. A size of less than 300 micrometers is recommended to meet the capillary driving force requirements of liquid working fluid, allowing the liquid working fluid to flow inside the reinforcing ribs under capillary force. The present invention provides a preferred embodiment, such asFigure 5 As shown, the characteristic scale of the millimeter-scale porous structure 7 within the reinforcing rib 2 is d. j The size is on the millimeter scale, with a recommended size of not less than 2mm and a porosity of not less than 50%, allowing the gaseous working fluid to pass through freely.

[0024] In a preferred embodiment of the present invention, the millimeter-scale porous structure 7 inside the reinforcing rib 2 can be selected from random porous structures such as foam metal, periodic unit cell structures such as lattice structures, or porous structures with gradient pore size variations, in order to meet the requirements of high porosity and high load-bearing capacity.

[0025] The present invention provides a preferred embodiment, such as Figure 4 As shown, the macroscopic-scale hole 8 within the reinforcing rib 2 has a characteristic scale d. M The dimensions are on the centimeter scale, meeting the requirements for gaseous working fluid passage under high ventilation conditions. Based on the gaseous working fluid flow cross-sectional requirements, the preliminary design of the number of macroscopic holes on the reinforcing ribs is given, with a number of n. The sum of the ventilation areas of the macroscopic holes is not less than 50% of the longitudinal cross-sectional area of ​​the reinforcing ribs. The macroscopic holes 8 within the reinforcing ribs 2 can be circular, elliptical, rhomboid, etc., and the hole size and layout design can meet the requirements for gaseous working fluid passage and structural load-bearing under high ventilation conditions.

[0026] Considering the pressure difference, temperature, and other environmental loads inside and outside the heat pipe, and based on stiffness and strength design, the initial stiffener thickness t and number m are given; characteristic dimensions w and d are considered. M n and d m The design comprehensively optimizes the size and distribution of macro and micro pores to meet the flow requirements of liquid working fluid in the channels and capillary structures inside the heat pipe shell, the capillary structures inside the reinforcing ribs, and the flow requirements of gaseous working fluid in the macro pores of the reinforcing ribs.

[0027] Alkali metal Na was selected as the working fluid, and nickel-based high-temperature alloy GH3044 was selected as the structural material.

[0028] The first step is to select the heat pipe wall thickness, channel parameters, and porous inner wall structure parameters based on the aerodynamic pressure load in the heat pipe design conditions, while ensuring structural strength and stiffness. Here, the channel width w is selected as 0.2 mm, the depth h as 0.4 mm, and the spacing as 2 mm. The characteristic pore size d of the porous inner wall structure is also considered. m The pore size is 0.2 mm. The characteristic pore size d in the reinforced porous structure is... j The diameter is 0.2 mm, and the porosity is 60%. There are 3 reinforcing ribs, and the wall thickness is 5 mm.

[0029] The second step is to establish a heat pipe heat and mass transfer analysis model that meets the parameters of the channel and capillary core for simulation, and calculate the structural temperature, deformation and thermal stress distribution according to the aerodynamic thermal load conditions. The third step is to determine whether the structural temperature, stiffness, and strength meet the design requirements based on the obtained temperature distribution. If they do, the current parameters of the stiffeners, channels, capillary cores, and cavity wall thickness are the final design parameters; otherwise, proceed to the next step. The fourth step involves redesigning the cavity wall thickness, the number and thickness of reinforcing ribs, and the cross-sectional area of ​​the channels, based on the current parameters and the working environment of the hypersonic vehicle. This process is repeated from the second step to the third step to obtain the final design parameters that meet the strength and stiffness requirements, thus completing the heat pipe design with a flow channel-free, reinforcing rib structure.

[0030] The above description is only the best specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the protection scope of the present invention.

[0031] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A reinforcing rib structure without flow channel obstruction inside a heat pipe, characterized in that: include: The system comprises a top plate, reinforcing ribs, a porous inner wall structure, an outer wall structure, and a bottom plate. The reinforcing ribs contain millimeter-scale porous structures and macroscopically sized pores. The porous inner wall structure contains microscopic pores, with the pores being on the order of hundreds of micrometers. The inner surfaces of the top and bottom plates are provided with capillary channels. The top plate, bottom plate, and outer wall structure form a closed, airtight structure. The microscopic pores and capillary channels in the porous inner wall structure form a liquid working fluid reflux channel. The millimeter-scale porous structures, macroscopically sized pores, and other cavities within the heat pipe closed structure of the reinforcing ribs serve as gaseous working fluid flow channels. The flow directions of the liquid and gaseous working fluids are perpendicular to the reinforcing ribs.

2. The reinforcing rib structure without flow channel obstruction in a heat pipe according to claim 1, characterized in that: The width w of the capillary channel structure is on the order of hundreds of micrometers.

3. The reinforcing rib structure without flow channel obstruction in a heat pipe according to claim 2, characterized in that: The width of the capillary channel structure is less than 300 micrometers.

4. The reinforcing rib structure without flow channel obstruction in a heat pipe according to claim 1, characterized in that: The characteristic scale of micropores is d m , less than 300 micrometers.

5. The reinforcing rib structure without flow channel obstruction in a heat pipe according to claim 1, characterized in that: The characteristic scale of the millimeter-scale porous structure of the reinforcing rib is d. j The diameter is not less than 2 mm and the porosity is not less than 50%.

6. The reinforcing rib structure without flow channel obstruction in a heat pipe according to claim 1, characterized in that: The upper surface of the porous reinforcing rib is connected to the ungrooved portion of the lower surface of the top plate, and the lower surface of the porous reinforcing rib is connected to the ungrooved portion of the upper surface of the bottom plate, ensuring the continuity of the capillary channels.

7. The reinforcing rib structure without flow channel obstruction in a heat pipe according to claim 1, characterized in that: The characteristic dimension of the macroscopic hole reserved for the reinforcing rib is d. M The value is on the order of centimeters; the number of macroscopic pores is n, and the sum of the ventilation areas of the macroscopic pores is not less than 50% of the longitudinal cross-sectional area of ​​the reinforcing rib.

8. The reinforcing rib structure without flow channel obstruction in a heat pipe according to claim 1, characterized in that: The top plate, reinforcing ribs, porous inner wall structure, outer wall structure, and bottom plate are made of nickel-based high-temperature alloy or refractory metal alloy, and are integrally formed by welding or 3D printing additive manufacturing process after individual component processing.

9. A reinforcing rib structure with no flow channel obstruction inside a heat pipe according to claim 1, characterized in that: The millimeter-scale porous structure inside the reinforcing rib can be a random porous structure, a periodic unit cell structure, or a porous structure with gradient pore size variation.

10. A reinforcing rib structure with no flow channel obstruction inside a heat pipe according to claim 1, characterized in that: The macroscopic holes on the reinforcing ribs are round holes, elliptical holes, and rhomboid holes.

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