An improved method for regulating the TPMS structure based on the Gyroid function and a heat exchanger structure

Abstract

The present invention discloses an improved method for regulating the TPMS structure based on the Gyroid function and a heat exchanger structure. Through a new improved Gyroid function regulation method, the flow channels of the Gyroid structure no longer have straight "through holes", avoiding excessive fluid flow along low-flow-resistance paths. At the same time, the wall curvature is increased. On the one hand, the surface area / volume ratio is increased, and on the other hand, the three-dimensional spiral perturbation of the fluid is enhanced, promoting efficient secondary flow (lateral mixing) and vortex effects, and enhancing the turbulent mixing ability. Based on this optimized TPMS structure, the heat transfer performance can be further improved, achieving more uniform and efficient heat transfer.

Description

Technical Field

[0001] The present invention belongs to the technical field of heat exchangers, and particularly relates to a method for improving the TPMS structure based on Gyroid function regulation and a heat exchanger structure. Background Art

[0002] Triply Periodic Minimal Surface (TPMS) is a periodic implicit surface with zero mean curvature. The TPMS lattice structure constructed based on this type of surface not only has excellent mechanical properties such as high specific strength, high specific stiffness, high specific surface area, and high energy absorption, but also has special functions such as good heat insulation and dissipation, noise reduction, damping and shock absorption, and electromagnetic shielding. Its excellent structural properties make it have a very broad application prospect in the fields of aerospace, electronic heat dissipation, biomedicine, etc.

[0003] The TPMS structure is also particularly important in the design of high-efficiency heat exchangers. While traditional heat exchanger structures (such as finned, corrugated tube, and microchannel heat exchangers) optimize the heat exchange efficiency, they usually face problems such as large flow resistance, poor flow uniformity, and complex manufacturing processes. In contrast, the TPMS structure achieves lower pressure drop losses, larger heat transfer areas, and more complex flow mixing characteristics through its highly adjustable topological morphology, thereby improving the heat exchange efficiency.

[0004] Diamond, Gyroid, and Tub-Primitive are three typical TPMS structures. Among the three TPMS structures, TPMS-Diamond has the best convective heat transfer performance, which can be attributed to the fact that its geometric structure has no "through holes", resulting in a stronger ability to disturb the fluid, thereby enhancing heat transfer; the Tub-Primitive structure has more through holes, resulting in less fluid flow resistance and not easily generating strong disturbances, but its effect in convective heat transfer is usually not as good as that of the Diamond structure, and it is suitable for low flow rate and relatively simple heat exchange scenarios, but has poor heat transfer effect at high flow rates.

[0005] The main advantage of the Gyroid structure lies in its complex three-dimensional surface, which gives it significant advantages in fluid flow, heat conduction performance, mechanical stability, and adaptability. Especially in applications that require uniform heat flow distribution and high heat exchange efficiency, the Gyroid structure performs excellently. In addition, its high strength-to-mass ratio and low fluid resistance make it an ideal choice in many engineering applications. Compared with the Diamond structure and the Tub-Primitive structure, the Gyroid structure provides better versatility, more uniform performance, and stronger adaptability.

[0006] However, the existing Gyroid structure still has certain limitations in heat transfer applications. First, the standard Gyroid structure has "through holes" that seemingly penetrate the flow channels, as Figure 1 shown. Such a structure causes some fluid to directly pass through the "through holes" without participating in lateral mixing and directly flow out of the heat exchanger, resulting in less heat absorption for this part of the fluid. This not only reduces the overall heat transfer efficiency but also leads to uneven temperature distribution in the heat exchanger. Second, although the TPMS structure can provide continuous flow channels, the walls of the standard Gyroid structure bend slowly, and the three-dimensional spiral perturbation of fluid flow is relatively small, making it difficult to form stronger turbulent mixing. Summary of the Invention

[0007] Aiming at the technical defects of the standard Gyroid structure in heat transfer applications, the present invention improves the standard Gyroid function, applies it to the improvement of the TPMS structure, and further uses the improved TPMS structure as the heat exchanger structure to improve the convective heat transfer ability of the TPMS structure.

[0008] An improved method for TPMS structure based on Gyroid function regulation, which introduces control terms containing control factor α to the three additive terms of the standard Gyroid function respectively to form an improved Gyroid function. By adjusting the magnitude of the control factor α, the size of the straight through holes and the tortuosity of the surface structure in the Gyroid structure are regulated. At the same time, the control terms of the additive terms in the xy plane contain the associated variable z, the control terms of the additive terms in the yz plane are associated with the variable x, and the control terms of the additive terms in the zx plane contain the associated variable y.

[0009] The core idea of this solution is that on each plane in the three-dimensional space, a periodic change in the perpendicular direction is added, and the control factor α is combined to adjust this periodic change, so that the surface morphology of the Gyroid structure changes significantly, and the shape and size of the straight through holes in the Gyroid structure also change significantly. Through the adjustment of the control factor α, the straight through holes can even completely disappear.

[0010] Preferably, the control term is a sine term or a cosine term, and the independent variable of this sine term or cosine term contains the control factor α.

[0011] Preferably, the independent variable of the control term of the additive term in the xy plane contains the sine and / or cosine of the variable z, the independent variable of the control term of the additive term in the yz plane contains the sine and / or cosine of the variable x, and the independent variable of the control term of the additive term in the zx plane contains the sine and / or cosine of the variable y.

[0012] For example, the control term of the additive term in the xy plane is , the control term of the additive term in the yz plane is , the control term of the additive term in the zx plane is 。

[0013] For another example, the control term of the added term in the xy plane is , the control term of the added term in the yz plane is , and the control term of the added term in the zx plane is 。

[0014] Preferably, the control term is the product of a sine term or a cosine term containing a control factor α and a sine term or a cosine term containing a correlation variable z / x / y; alternatively, the control term is the product of a sine term or a cosine term containing a control factor α, a sine term containing a correlation variable z / x / y, and a cosine term containing a correlation variable z / x / y, which are three terms.

[0015] For example, the control term of the added term in the xy plane is , the control term of the added term in the yz plane is , and the control term of the added term in the zx plane is 。Hereinafter, L always represents the unit length of the TPMS structure.

[0016] The present invention also protects a heat exchanger structure obtained by improving the above TPMS structure.

[0017] Through a new improved Gyroid function regulation method, the present invention makes the flow channels of the Gyroid structure no longer have straight "through holes", avoiding excessive fluid flow along low-resistance paths, and at the same time increasing the wall curvature. On the one hand, the surface area / volume ratio is increased, and on the other hand, the three-dimensional spiral perturbation of the fluid is strengthened, promoting efficient secondary flow (lateral mixing) and vortex effect, enhancing the turbulent mixing ability, thereby further improving the heat transfer performance and achieving more uniform and efficient heat transfer. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic diagram of a straight through hole of a standard Gyroid structure;

[0019] Figure 2 is a schematic diagram of the structure of a standard Gyroid, where (a) is a schematic diagram of the unit structure and (b) is a schematic diagram of the array structure;

[0020] Figure 3 is a three-dimensional view and a top view of the Gyroid unit structure disclosed in Example 1 under different α values;

[0021] Figure 4(a) is a three-dimensional view of the Gyroid unit structure disclosed in Example 2 when α takes 20 / π;

[0022] Figure 4(b) is a top view of the Gyroid unit structure disclosed in Example 2 when α takes 20 / π;

[0023] Figure 5(a) is a three-dimensional view of the Gyroid unit structure disclosed in Example 3 when α is 0.5.

[0024] Figure 5(b) is a top view of the Gyroid unit structure disclosed in Example 3 when α is 0.5;

[0025] Figure 6(a) is a three-dimensional view of the Gyroid unit structure disclosed in Example 4 when α is 20 / π;

[0026] Figure 6(b) is a top view of the Gyroid unit structure disclosed in Example 4 when α is 20 / π;

[0027] Figure 7(a) is a three-dimensional view of the Gyroid unit structure disclosed in Example 5 when α is 0.5;

[0028] Figure 7(b) is a top view of the Gyroid unit structure disclosed in Example 5 when α is 0.5;

[0029] Figure 8(a) is a three-dimensional view of the Gyroid unit structure disclosed in Example 6 when α is 40 / π;

[0030] Figure 8(b) is a top view of the Gyroid unit structure disclosed in Example 6 when α is 40 / π;

[0031] Figure 9(a) is a three-dimensional view of the Gyroid unit structure disclosed in Example 7 when α is 0.5;

[0032] Figure 9(b) is a top view of the Gyroid unit structure disclosed in Example 7 when α is 0.5. Detailed implementation manners

[0033] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners. The embodiments of the present invention are given for purposes of illustration and description, and are not intended to be exhaustive or to limit the invention to the disclosed form. Many modifications and variations are obvious to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present invention, and to enable those of ordinary skill in the art to understand the present invention and thus design various embodiments with various modifications suitable for specific purposes.

[0034] Porous structures can be seen everywhere in nature. A porous medium is a solid structure that contains pores and a basic solid framework that forms the material itself. Common porous structures can be divided into disordered and ordered. Disordered porous structures can be further divided into open-cell structures and closed-cell structures, and common ones include foam porous structures; common ordered porous structures include truss-like structures, sieve structures, honeycomb structures, and the latest TPMS structures. The Gyroid structure is one of the three typical TPMS structures.Figure 2 The schematic diagrams of the unit structure (a) and the array structure (b) of the standard Gyroid are given.

[0035] Standard Gyroid function equation:

[0036] .

[0037] Thermal performance refers to the influence of the overall structure on the overall temperature distribution under the action of external thermal loads, including heat conduction, heat convection, and heat radiation. Due to the severe flight environment and special flight missions, compared with ordinary aircraft, the performance requirements for the thermal protection system of aerospace vehicle structures are high, and its design is extremely important. In the field of aerospace, there is always a contradiction in the development of thermal protection structures between improving the efficiency of thermal protection structures, reducing the structural mass, and withstanding the harsh aerodynamic heating environment of hypersonic vehicles. The present invention aims to provide an improved Gyroid function and regulate the TPMS structure based on this Gyroid function to significantly enhance its convective heat transfer performance and achieve more efficient heat energy transfer.

[0038] Example 1

[0039] The improved Gyroid function equation given in this example:

[0040]

[0041] Where L represents the unit length of the TPMS structure, and C represents the offset of the original unit surface. These control terms are selected because they can precisely control the structure without damaging its inherent topological structure and connectivity.

[0042] Figure 3 The three-dimensional view and top view of the Gyroid unit structure at different α values are shown. It can be seen that by adjusting the magnitude of the control factor α, the surface morphology of the Gyroid structure changes significantly. When α is 0, the improved Gyroid unit structure is exactly the same as the standard Gyroid unit structure.

[0043] From the top view perspective, as the control factor α increases, the shape and size of the straight through holes in the Gyroid structure change significantly. The straight through holes gradually change from circular to approximately quadrilateral in shape, and the overall area of the straight through holes is continuously shrinking. When α reaches 0.45L, the straight through holes completely disappear. Combining the three-dimensional perspective, as the control factor α increases, the surface morphology in the Gyroid structure also gradually becomes more tortuous, which is beneficial to increasing the contact area between the fluid and the solid surface and enhancing the formation of turbulence on the structure surface.

[0044] By adjusting the magnitude of α, not only can the size of the straight through holes be adjusted to effectively prevent the fluid from preferentially flowing through the low flow resistance regions, thereby improving the heat transfer efficiency between the fluid and the solid surface. At the same time, the improved Gyroid unit structure also forms surface structures with different degrees of tortuosity, enhancing the perturbation effect of the fluid and making it easier to form efficient secondary flows and vortex effects during the fluid flow process.

[0045] Example 2

[0046] The improved Gyroid function equation given in this example:

[0047] ,

[0048] Based on Example 1, in this example, the cosine containing the associated variables z / x / y is deleted. Figures 4(a) and 4(b) are the three-dimensional view and the top view respectively when α takes 20 / π.

[0049] Example 3

[0050] The improved Gyroid function equation given in this example:

[0051] ,

[0052] Based on Example 2, in this example, the control term of the cosine is changed to sine. Figures 5(a) and 5(b) are the three-dimensional view and the top view respectively when α takes 0.5.

[0053] Example 4

[0054] The improved Gyroid function equation given in this example:

[0055] ,

[0056] Based on Example 1, in this example, the sine containing the associated variables z / x / y is deleted. Figures 6(a) and 6(b) are the three-dimensional view and the top view respectively when α takes 20 / π.

[0057] Example 5

[0058] The improved Gyroid function equation given in this example:

[0059] ,

[0060] Based on Example 4, in this example, the control term of the cosine is changed to sine. Figures 7(a) and 7(b) are the three-dimensional view and the top view respectively when α takes 0.5.

[0061] Example 6

[0062] The improved Gyroid function equation given in this embodiment:

[0063] ,

[0064] Based on Embodiment 1, in this embodiment, the control term of cosine is changed to sine. Figures 8(a) and 8(b) are the three-dimensional view and top view respectively when α is 40 / π.

[0065] Embodiment 7

[0066] The improved Gyroid function equation given in this embodiment:

[0067] ,

[0068] Based on Embodiment 1, in this embodiment, the control factor α and the associated variables z / x / y are decoupled and split into independent control factors, which are multiplied to obtain the control term. Figures 9(a) and 9(b) are the three-dimensional view and top view respectively when α is 0.5.

[0069] Combining Embodiments 2 - 7, it can be seen that the morphologies of the straight through-holes can be changed by adjusting the values of the control factors for these deformed and adjusted control terms, achieving the effect of eliminating the straight through-holes.

[0070] Embodiment 8

[0071] This embodiment proposes a heat exchanger structure, which is obtained based on the TPMS structure improvement method described in Embodiments 1 - 7.

[0072] Compared with the heat exchanger based on the standard Gyroid structure, the flow channels of the heat exchanger structure designed in this embodiment no longer have straight "through-holes", avoiding excessive fluid flow along the low-flow-resistance paths. At the same time, the wall bending degree is increased. On the one hand, the surface area / volume ratio is increased, and on the other hand, the three-dimensional spiral perturbation of the fluid is strengthened, promoting efficient secondary flow (lateral mixing) and vortex effects, enhancing the turbulent mixing ability, and thus significantly improving the convective heat transfer performance and achieving more efficient heat energy transfer.

[0073] Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art and related fields based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

Claims

1. A heat exchanger structure based on Gyroid function control, characterized in that: The control term including the control factor α is introduced into the three addends of the standard Gyroid function to form an improved Gyroid function. The size of the through hole in the Gyroid structure and the tortuosity of the surface structure are controlled by adjusting the size of the control factor α, wherein the control term is a sine term or a cosine term, and the independent variable of the sine term or the cosine term includes the control factor α. The control term for the addend in the xy plane is , the control term of the addend in the yz plane is , the control term of the addend in the zx plane is , where L represents the unit length of the TPMS structure.

2. The heat exchanger structure according to claim 1, characterized in that: As an alternative, the control term for the addend in the xy plane is , the control term of the addend in the yz plane is , the control term of the addend in the zx plane is .

3. The heat exchanger structure according to claim 1, characterized in that: As an alternative, The control term for the addend in the xy plane is , the control term of the addend in the yz plane is , the control term of the addend in the zx plane is .

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