CN111780601A - Design method of vapor chamber liquid absorption core structure with enhanced capillary action - Google Patents

Design method of vapor chamber liquid absorption core structure with enhanced capillary action Download PDF

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CN111780601A
CN111780601A CN202010632076.1A CN202010632076A CN111780601A CN 111780601 A CN111780601 A CN 111780601A CN 202010632076 A CN202010632076 A CN 202010632076A CN 111780601 A CN111780601 A CN 111780601A
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CN111780601B (en
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李宝童
徐俊豪
尹鑫鑫
苏文杰
洪军
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Xian Jiaotong University
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
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Abstract

A method for designing a vapor chamber liquid absorption core structure with enhanced capillary action is based on Poisea flow hypothesis, the similarity between ideal Poisea flow and steady-state heat conduction is utilized, the steady-state heat conduction problem optimization sector part is taken as a first-order configuration of vapor chamber condensation end topological optimization, and then the plant vein bifurcation rule is utilized to optimize micro-channel layout in a sector area to obtain a liquid absorption core structure; the layout of the flow channels in the soaking core of the soaking plate is designed by simulating the distribution of the leaf veins of the plant leaves, so that the capillary force is ensured, the flow velocity is high, and the obtained soaking core structure has more excellent thermal performance.

Description

Design method of vapor chamber liquid absorption core structure with enhanced capillary action
Technical Field
The invention relates to the technical field of layout design of inner flow channels of a vapor chamber liquid absorption core, in particular to a design method of a vapor chamber liquid absorption core structure with a strengthened capillary effect.
Background
As electronic devices are increasingly highly integrated and miniaturized, if efficient and rapid heat dissipation means is not available, the electronic devices may be in a relatively high temperature state during operation, which may cause degradation of device performance and reliability. A vapor chamber is a widely used heat sink, which transfers heat of an electronic device to a heat sink through phase change of a working fluid inside a chamber thereof. The performance of the vapor chamber will directly affect the temperature of the surface of the device during operation, and the performance of the vapor chamber depends on the internal wick structure, so the layout of the flow channels in the wick of the vapor chamber becomes the design key.
The traditional soaking plate is mainly designed by depending on experience or simply combining flow channels, the micro flow channels in the soaking plate are mostly rectangular flow channels and snake-shaped flow channels, the flow channels are simple in design and easy to process and manufacture, but along with the development of electronic equipment, the thermal performance requirements of a radiator are continuously improved, and the traditional flow channels cannot meet the current requirement of heat transfer enhancement.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention aims to provide a method for designing a vapor chamber liquid absorption core structure with enhanced capillary action.
In order to achieve the aim, the invention adopts the technical scheme that:
a method for designing a vapor chamber liquid absorbing core structure for strengthening capillary action comprises the following steps:
(1) derivation of the first-order configuration of the wick structure:
the height of a flow channel in the vapor chamber liquid absorption core structure is dozens to hundreds of microns, the flow channel is regarded as a Poiseup flow between parallel flat plates, a proportional relation exists between the flow rate and the pressure drop, a proportional relation (Fourier law) also exists between the heat flow density and the temperature gradient in the flat plate in a steady-state heat conduction state, and the proportionality coefficients of the flow channel and the temperature gradient are related material parameters; according to similarity analysis of ideal Poisea flow and steady-state heat conduction, taking the optimized sector part of the steady-state heat conduction problem as a first-order configuration of topological optimization of a soaking plate wick structure;
first, wick structures fall into two broad categories: the "surface point" (AP) problem in the condensation end wick design and the "surface line" (AL) problem in the evaporation end wick design; then, deriving a disc model with a high heat conduction channel, wherein the division number of the disc is selected as an optimization variable, and the volume ratio of the fixed high heat conduction channel and the minimum micro-milling machining size are used as constraint conditions;
for the evaporation end, the circumferential side of the sector area is a heat sink, the widths of two ends of the high heat conduction channel are respectively D and mD, the length of the high heat conduction channel is L, and the fire integral of the high heat conduction channel is solved by three parts:
partial fire volume in the sector central angle region:
Figure BDA0002565975080000021
fire accumulation of high heat conduction channel:
Figure BDA0002565975080000022
the fire accumulation of the area parts at two sides of the high heat conduction channel:
Figure BDA0002565975080000031
total accumulated fire:
Figure BDA0002565975080000032
for the condensation end, the circle center side of the fan-shaped area is a heat sink, the widths of two ends of the high heat conduction channel are respectively D and mD, the length of the high heat conduction channel is R, and the fire integral of the high heat conduction channel is solved by two parts:
partial fire accumulation of high heat conduction channel:
Figure BDA0002565975080000033
the fire accumulation of the area parts at two sides of the high heat conduction channel:
Figure BDA0002565975080000034
total accumulated fire:
Figure BDA0002565975080000035
where R is the disk radius, q' is the disk heat generation rate, w is the disk thickness, T (x, y) is the temperature at (x, y), α is the fan center angle, T is the disk thicknessminIs the temperature at the heat sink.
Meanwhile, the intensity of heat flow at the high heat conduction channel at the right side of the constrained condensation end is far greater than that of heat flow at the low heat conduction area, and the mathematical expression is as follows:
Figure BDA0002565975080000036
by the theoretical solution, corresponding to the minimum fire product dissipation rate, the divided parts of the liquid absorption core discs at the condensation end and the evaporation end are optimized to obtain a first-order configuration of the liquid absorption core structure;
(2) constructing a micro-channel capillary force model:
the height of water rising in a capillary is used as an index for measuring the working capacity of a liquid absorption core, the length of the capillary of a micro-channel is L, the width of the capillary of the micro-channel is W, the depth of the capillary of the micro-channel is H, the micro-channel is arranged in water, and the surface tension is expressed by Helmholtz free energy assuming that the environmental temperature factor is kept constant:
σij＝dE/dAij,i,j＝f,s,v and i≠j (9)
wherein A isijRepresents the area of the boundary region, σsv、σslAnd σlvRespectively representing the surface tension of solid gas, solid liquid and liquid gas; the variation of Helmholtz free energy at the interface is then expressed as:
dE＝σlvdAlv+σsldAsl+σsvdAsv(10)
assuming that the height of the liquid level in the capillary at a certain moment is x, and the liquid level moves a small distance dx upwards under the pushing of the capillary force, the variation of the contact area at the junction of liquid and gas, solid and liquid and solid and gas is as follows:
dAlv＝Wdx (11)
dAsl＝(2H+W)dx (12)
dAsv＝-(2H+W)dx (13)
when liquid drops with a certain volume are attached to the surface of a smooth solid, the liquid drops can be spread along the surface of the solid until three contact lines of solid and liquid and gas reach balance, and the angle formed by the tangent line of the gas-liquid interface and the solid-liquid contact surface is the three contact angles theta; then the Young contact equation is obtained:
σsv＝σsl+σlvcosθ (14)
substituting equations (11) - (14) into equation (10) may result:
dE＝σlv[W-(2H+W)cosθ]dx (15)
the capillary force F is then obtained by integrating dE over dx:
Figure BDA0002565975080000041
(3) layout design of internal flow channels of the liquid absorption core:
the driving force of the working medium flowing in the liquid absorption core is the capillary force provided by the liquid absorption core structure, when the capillary structure is a round pipe, the size of the capillary pressure is determined by the radius of the capillary, for measuring the capillary liquid absorption core structure, the capillary pressure and the permeability are taken as two key parameters, and the weighted sum of the surface tension and the flow rate at the tail end of the maximized flow channel is taken as a topological optimization target:
Figure BDA0002565975080000051
in the formula: w is a1And w2Respectively, the terminal surface tension g in the objective function1(f) And the weight occupied by flow rate g2 (u);
the constraint conditions are set as flow channel volume ratio constraint and design domain constraint;
summarizing the bifurcation rule of the plant veins aiming at the dicotyledonous plant vein self-adaptive thermal structure, and applying the bifurcation rule to the structural design of a vapor chamber liquid absorption core; assuming that the final flow path is made up of modules, each module is controlled by a set of independent vectors, X ═ L, t1,t2,t3,θ]TThe layout of the flow channel is formed by growth, degradation and deformation of the component, and the specific growth simulation process is divided into three steps:
step 3.1: initializing, and setting initial boundary conditions of an evaporation end and a condensation end;
step 3.2: growth competition, optimizing the size and steering of each component, includes two substeps: local adjustment and global adjustment; local adjustment refers to optimizing newly generated components, and total adjustment refers to optimizing all generated components;
step 3.3: calculating a bifurcation threshold and a degradation threshold, and for the newly generated assembly, if the thickness of the tail end of the assembly is larger than a bifurcation value, further bifurcating; if the thickness of the component end is less than the degradation threshold, the component is removed; if the thickness of the component is between the two thresholds, no new component will grow at the end of the component;
step 3.2 and step 3.3 are alternately carried out until the volume ratio of the high heat conduction channel reaches the set volume ratio, and the layout of the high heat conduction channel is generated;
(4) adaptive processing: and rounding the flow channel layout according to the production process requirements so as to obtain the final layout of the flow channel.
The invention has the beneficial effects that:
the invention does not need to depend on the inspiration and experience of designers, and can reduce the labor cost; the surface tension and the flow rate at the tail end of the flow channel are used as objective functions to optimize the structure of the liquid suction core, so that the optimized micro-flow channel layout has larger flow rate while the capillary force is ensured; according to the dicotyledonous plant leaf vein self-adaptive thermal structure, the correlation between physical parameters such as a micro-channel fractal structure, a mesophyll porous structure and leaf thickness and a leaf self-adaptive heat dissipation mechanism is researched, the layout of a flow channel in a soaking plate liquid absorption core is designed by simulating the distribution of plant leaf veins, and the liquid absorption core structure obtained through optimization by the method has better thermal performance than a traditional structure.
Drawings
FIG. 1 is a first order configuration derived mathematical model of an evaporative end wick structure according to the present invention.
FIG. 2 is a first order configuration derived mathematical model of the wick structure of the condensation end of the present invention.
FIG. 3 is a diagram showing a construction of a capillary force model according to the present invention, wherein (a) is a front view and (b) is a plan view.
Fig. 4 is a flow channel layout of a condensation-side wick structure designed according to the present invention.
Fig. 5 is a flow channel layout of an evaporation end wick structure designed according to the present invention.
Detailed Description
The design method provided by the invention can be used for the design of the enhanced capillary action of the wick structure of various groove type soaking plates, and the invention is mainly described in detail by taking the condensation end as an example and combining the attached drawings and the example.
A method for designing a vapor chamber liquid absorbing core structure for strengthening capillary action comprises the following steps:
(1) derivation of the first-order configuration of the wick structure:
the height of a flow channel in the vapor chamber liquid absorption core structure is dozens to hundreds of microns, the flow channel is regarded as the poiseuille flow between parallel flat plates, the relation between the flow speed and the pressure gradient of the poiseuille flow and the relation between the heat flow density and the temperature gradient in the flat plate in a steady-state heat conduction state (Fourier law) are contrastively analyzed, the proportional relation between potential energy gradient and transfer speed exists in the poiseuille flow between the parallel flat plates and the steady-state heat conduction in the flat plate, the proportional coefficients are related material physical parameters, and the corresponding mass transfer/heat transfer quantity is the product of the transfer speed and the sectional area; according to the similarity analysis of the ideal Poisea flow and the steady-state heat conduction, the optimized sector part of the steady-state heat conduction problem is taken as a first-order configuration of topological optimization of the condensation end of the soaking plate;
first, wick structures can be divided into two broad categories: the "surface point" (AP) problem in the condensation end wick design and the "surface line" (AL) problem in the evaporation end wick design. Then, deriving a disc model with a high heat conduction channel, wherein the division number of the disc is selected as an optimization variable, and the volume ratio of the fixed high heat conduction channel and the minimum micro-milling machining size are used as constraint conditions; it is assumed here that the wick structure is machined by micro-milling, so that the dimensions of the restricted flow channel are not less than 0.01 mm;
as shown in fig. 1, for the evaporation end, the circumferential side of the sector area is a heat sink, the widths of the two ends of the high thermal conduction channel are D and mD, the length is L, and the fire integral is solved by three parts:
partial fire volume in the sector central angle region:
Figure BDA0002565975080000071
fire accumulation of high heat conduction channel:
Figure BDA0002565975080000072
the fire accumulation of the area parts at two sides of the high heat conduction channel:
Figure BDA0002565975080000081
total accumulated fire:
Figure BDA0002565975080000082
as shown in fig. 2, for the condensation end, the circle center side of the sector area is a heat sink, the widths of the two ends of the high heat conduction channel are D and mD respectively, the length is R, and the fire product can be solved by dividing into two parts:
partial fire accumulation of high heat conduction channel:
Figure BDA0002565975080000083
the fire accumulation of the area parts at two sides of the high heat conduction channel:
Figure BDA0002565975080000084
total accumulated fire:
Figure BDA0002565975080000085
where R is the disk radius, q' is the disk heat generation rate, w is the disk thickness, T (x, y) is the temperature at (x, y), α is the fan center angle, T is the disk thicknessminIs the temperature at the heat sink;
meanwhile, the intensity of heat flow at the high heat conduction channel at the right side of the condensation end is restrained to be far greater than that of heat flow at the low heat conduction area, wherein the intensity of heat flow at the high heat conduction channel is far greater than that of heat flow at the low heat conduction area by 10 times or more, and then the formula (8) is changed into:
Figure BDA0002565975080000086
the specific values of the parameters used are shown in table 1:
TABLE 1 disc parameter numerical table
Figure BDA0002565975080000087
Figure BDA0002565975080000091
By the theoretical solution, corresponding to the minimum fire product dissipation rate, optimizing the divided parts of the liquid absorption core discs at the condensation end and the evaporation end, wherein the optimal part for the final optimization is 18 parts, and obtaining a first-order configuration of the liquid absorption core structure;
(2) constructing a micro-channel capillary force model:
the rising height of water in a capillary tube is generally taken as an important index for measuring the working capacity of a liquid absorption core, and the length, the width and the depth of the microchannel capillary tube are assumed to be L, W and H; as shown in fig. 3, the microchannel is stood in water, and assuming that factors such as ambient temperature remain constant, the surface tension can be expressed by Helmholtz free energy:
σij＝dE/dAij,i,j＝f,s,v and i≠j (9)
wherein A isijRepresents the area of the boundary region, σsv、σslAnd σlvRespectively representing the surface tension of solid gas, solid liquid and liquid gas; the variation of Helmholtz free energy at the interface is then expressed as:
dE＝σlvdAlv+σsldAsl+σsvdAsv(10)
assuming that the height of the liquid level in the capillary at a certain moment is x, and the liquid level moves a small distance dx upwards under the pushing of the capillary force, the variation of the contact area at the junction of liquid and gas, solid and liquid and solid and gas is as follows:
dAlv＝Wdx (11)
dAsl＝(2H+W)dx (12)
dAsv＝-(2H+W)dx (13)
when liquid drops with a certain volume are attached to the surface of a smooth solid, the liquid drops can be spread along the surface of the solid until three contact lines of solid and liquid and gas reach balance, and the angle formed by the tangent line of the gas-liquid interface and the solid-liquid contact surface is the three contact angles theta; then the Young contact equation can be obtained:
σsv＝σsl+σlvcosθ (14)
substituting equations (11) - (14) into equation (10) can result:
dE＝σlv[W-(2H+W)cosθ]dx (15)
the capillary force F can be obtained by integrating dE over dx:
Figure BDA0002565975080000101
(3) layout design of internal flow channels of the liquid absorption core:
the driving force of the working medium flowing in the liquid absorbing core provides the capillary force for the liquid absorbing core structure, if the capillary force is too small, the evaporation end can not be supplemented with new liquid working medium after the working medium in the evaporation end is completely evaporated, so that the vapor chamber can lose the original effect; when the capillary structure is a round tube, the capillary pressure is determined by the radius of the capillary tube, and the smaller the radius of the round tube is, the larger the capillary pressure is, but the larger the flow resistance in the round tube is, and the smaller the permeability is; therefore, for measuring the capillary liquid absorption core structure, the capillary pressure and the permeability are taken as two key parameters and are a pair of contradictory unity, and the key of the soaking plate research is to find a balance in the two contradictory unity so as to maximize the weighted sum of the surface tension and the flow velocity at the tail end of the flow channel as the topological optimization target:
Figure BDA0002565975080000102
in the formula: w is a1And w2Respectively, the terminal surface tension g1 (f) in the objective functionc) And the weight occupied by flow rate g2 (u);
the constraint conditions are set as flow channel volume ratio constraint, design domain constraint and the like;
aiming at a dicotyledonous plant vein self-adaptive thermal structure, the correlation between physical parameters such as a micro-channel fractal structure, a mesophyll porous structure and the thickness of a blade and a blade self-adaptive heat dissipation mechanism is researched, on the basis, the bifurcation rule of the plant vein is summarized, and the plant vein is applied to the structural design of a soaking plate liquid absorption core; assuming that the final flow path is made up of modules, each module is controlled by a set of independent vectors, X ═ L, t1,t2,t3,θ]TForming a layout of a flow channel by growth, degradation, deformation, or the like of the component; the specific growth simulation process can be divided into three steps:
step 3.1: initializing, setting initial boundary conditions of an evaporation end and a condensation end, and setting the initialized values of a control vector X of the component as shown in Table 2:
TABLE 2 setting of control vectors
Figure BDA0002565975080000111
For subsequent growth simulations, the values of the other parameters were defined as follows: the radius of the disc is 30mm, and the thickness of the disc is 0.3 mm; the heat generation rate of the disc is 0.1W/mm3And the thermal conductivity of the disc is K00.4W/(m · K); the temperature of the heat sink is set to be 25 ℃, the heat conductivity of the high heat conduction channel is 400W/(m.K), and the volume ratio of the high heat conduction channel to the disc is 25%;
step 3.2: growth competition, optimizing the size and steering of each component, includes two substeps: local adjustment and global adjustment; local adjustment refers to optimizing newly generated components, and total adjustment refers to optimizing all generated components;
step 3.3: calculating a bifurcation threshold and a degradation threshold:
Figure BDA0002565975080000112
Figure BDA0002565975080000113
wherein WbAnd WdThreshold values for bifurcation and degeneration, respectively, AbAnd AdIs the control coefficient of the bifurcation and degradation thresholds, in this embodiment, AbAnd AdSet to 0.8 and 0.2, N, respectively(k)And N(k-1)When the k-th step and the (k-1) -th step are finished, the number of the control vectors of the existing components, t1、t2、t3The thicknesses of the head end, the tail end and the middle of the component are respectively;
for a newly generated component, if the thickness of the component end is greater than the bifurcation value, the component can be further bifurcated; if the thickness of the end of the element is less than the degradation threshold, the element will be removed; if the thickness of the component is between the two thresholds, no new component will grow at the end of the component;
step 3.2 and step 3.3 are alternately carried out until the volume ratio of the high heat conduction channel reaches 25%, and the layout of the high heat conduction channel is generated;
(4) adaptive processing: the heat conducting flow channel layout is rounded according to the production process requirements, so that the final layout of the flow channel is obtained, wherein the condensation end is shown in figure 4, and the evaporation end is shown in figure 5.

Claims (1)

1. A method for designing a vapor chamber liquid absorption core structure for strengthening capillary action is characterized by comprising the following steps:
(1) derivation of the first-order configuration of the wick structure:
the height of a flow channel in the vapor chamber liquid absorption core structure is dozens to hundreds of microns, the flow channel is regarded as a Poiseup flow between parallel flat plates, a proportional relation exists between the flow rate and the pressure drop, a proportional relation (Fourier law) also exists between the heat flow density and the temperature gradient in the flat plate in a steady-state heat conduction state, and the proportionality coefficients of the flow channel and the temperature gradient are related material parameters; according to similarity analysis of ideal Poisea flow and steady-state heat conduction, taking the optimized sector part of the steady-state heat conduction problem as a first-order configuration of topological optimization of a soaking plate wick structure;
first, wick structures fall into two broad categories: the "surface point" (AP) flow problem in the condensation end wick design and the "surface line" (AL) flow problem in the evaporation end wick design; then, deriving a disc model with a high heat conduction channel, wherein the division number of the disc is selected as an optimization variable, and the volume ratio of the fixed high heat conduction channel and the minimum micro-milling machining size are used as constraint conditions;
for the evaporation end, the circumferential side of the sector area is a heat sink, the widths of two ends of the high heat conduction channel are respectively D and mD, the length of the high heat conduction channel is L, and the fire integral of the high heat conduction channel is solved by three parts:
partial fire volume in the sector central angle region:
Figure FDA0002565975070000011
fire accumulation of high heat conduction channel:
Figure FDA0002565975070000012
the fire accumulation of the area parts at two sides of the high heat conduction channel:
Figure FDA0002565975070000021
total accumulated fire:
Figure FDA0002565975070000022
for the condensation end, the circle center side of the fan-shaped area is a heat sink, the widths of two ends of the high heat conduction channel are respectively D and mD, the length of the high heat conduction channel is R, and the fire integral of the high heat conduction channel is solved by two parts:
partial fire accumulation of high heat conduction channel:
Figure FDA0002565975070000023
the fire accumulation of the area parts at two sides of the high heat conduction channel:
Figure FDA0002565975070000024
total accumulated fire:
Figure FDA0002565975070000025
where R is the disk radius, q' is the disk heat generation rate, w is the disk thickness, T (x, y) is the temperature at (x, y), α is the fan center angle, T is the disk thicknessminIs the temperature at the heat sink.
Meanwhile, the intensity of heat flow at the high heat conduction channel at the right side of the constrained condensation end is far greater than that of heat flow at the low heat conduction area, and the mathematical expression is as follows:
Figure FDA0002565975070000026
by the theoretical solution, corresponding to the minimum fire product dissipation rate, the divided parts of the liquid absorption core discs at the condensation end and the evaporation end are optimized to obtain a first-order configuration of the liquid absorption core structure;
(2) constructing a micro-channel capillary force model:
the height of water rising in a capillary is used as an index for measuring the working capacity of a liquid absorption core, the length of the capillary of a micro-channel is L, the width of the capillary of the micro-channel is W, the depth of the capillary of the micro-channel is H, the micro-channel is arranged in water, and the surface tension is expressed by Helmholtz free energy assuming that the environmental temperature factor is kept constant:
σij＝dE/dAij,i,j＝f,s,v and i≠j (9)
wherein A isijRepresents the area of the boundary region, σsv、σslAnd σlvRespectively representing the surface tension of solid gas, solid liquid and liquid gas; the variation of Helmholtz free energy at the interface is then expressed as:
dE＝σlvdAlv+σsldAsl+σsvdAsv(10)
assuming that the height of the liquid level in the capillary at a certain moment is x, and the liquid level moves a small distance dx upwards under the pushing of the capillary force, the variation of the contact area at the junction of liquid and gas, solid and liquid and solid and gas is as follows:
dAlv＝Wdx (11)
dAsl＝(2H+W)dx (12)
dAsv＝-(2H+W)dx (13)
when liquid drops with a certain volume are attached to the surface of a smooth solid, the liquid drops can be spread along the surface of the solid until three contact lines of solid and liquid and gas reach balance, and the angle formed by the tangent line of the gas-liquid interface and the solid-liquid contact surface is the three contact angles theta; then the Young contact equation is obtained:
σsv＝σsl+σlvcosθ (14)
substituting equations (11) - (14) into equation (10) may result:
dE＝σlv[W-(2H+W)cosθ]dx (15)
the capillary force F is then obtained by integrating dE over dx:
Figure FDA0002565975070000031
(3) layout design of internal flow channels of the liquid absorption core:
the driving force of the working medium flowing in the liquid absorption core is the capillary force provided by the liquid absorption core structure, when the capillary structure is a round pipe, the size of the capillary pressure is determined by the radius of the capillary, for measuring the capillary liquid absorption core structure, the capillary pressure and the permeability are taken as two key parameters, and the weighted sum of the surface tension and the flow rate at the tail end of the maximized flow channel is taken as a topological optimization target:
Figure FDA0002565975070000041
in the formula: w is a1And w2Respectively, the terminal surface tension g in the objective function1(f) And flow rate g2(u) the weight occupied;
the constraint conditions are set as flow channel volume ratio constraint and design domain constraint;
summarizing the bifurcation rule of the plant veins aiming at the dicotyledonous plant vein self-adaptive thermal structure, and applying the bifurcation rule to the structural design of a vapor chamber liquid absorption core; assuming that the final flow path is made up of modules, each module is controlled by a set of independent vectors, X ═ L, t1,t2,t3,θ]TThe layout of the flow channel is formed by growth, degradation and deformation of the component, and the specific growth simulation process is divided into three steps:
step 3.1: initializing, and setting initial boundary conditions of an evaporation end and a condensation end;
step 3.2: growth competition, optimizing the size and steering of each component, includes two substeps: local adjustment and global adjustment; local adjustment refers to optimizing newly generated components, and total adjustment refers to optimizing all generated components;
step 3.3: calculating a bifurcation threshold and a degradation threshold, and for the newly generated assembly, if the thickness of the tail end of the assembly is larger than a bifurcation value, further bifurcating; if the thickness of the component end is less than the degradation threshold, the component is removed; if the thickness of the component is between the two thresholds, no new component will grow at the end of the component;
step 3.2 and step 3.3 are alternately carried out until the volume ratio of the high heat conduction channel reaches the set volume ratio, and the layout of the high heat conduction channel is generated;
(4) adaptive processing: and rounding the flow channel layout according to the production process requirements so as to obtain the final layout of the flow channel.
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