Method, device and equipment for analyzing heat transfer characteristics of nanofluid and medium

Abstract

The invention relates to the technical field of fluid heat dissipation, in particular to a heat transfer characteristic analysis method, device and equipment of nanofluid and a medium. According to the method, a velocity calculation formula is constructed based on a power law fluid model, then the velocity calculation formula is applied to the slip length, the fluid attribute information and the pipeline attribute information to obtain the flow velocity of the nanofluid in the miniature pipeline, then the average temperature of the nanofluid in the miniature pipeline is calculated based on the flow velocity, and finally the temperature of the nanofluid in the miniature pipeline is calculated based on the average temperature. And calculating the Nusselt number of the nanofluid in the miniature pipeline. The power law fluid model can describe the non-Newtonian characteristics of the nanofluid, and the non-Newtonian characteristics are suitable for the heat transfer characteristics of the nanofluid in the miniature pipeline, so that the flow velocity, the average temperature and the Nusselt number can describe the heat transfer characteristics of the nanofluid in the miniature pipeline; therefore, the nanofluid can be applied to micro-scale cooling.

Description

Technical Field

[0001] The present invention relates to the technical field of fluid heat dissipation, and in particular to a method, device, equipment and medium for analyzing heat transfer characteristics of nanofluids. Background Art

[0002] Nanoscale metal particles (diameter of metal particles is 1 to 100 nm) are doped into liquid to form a mixed liquid, which is called nanofluid. Nanoscale metal particles have a large relative surface area, which helps to enhance heat transfer. Moreover, since their geometric scale is closer to liquid molecules, they can remain suspended in the liquid for a long time and are not easy to precipitate. Nanoparticles commonly used to prepare nanofluids are divided into two categories: (1) metal particles, such as Cu, Al, Fe, Au, and Ag; (2) metal oxide particles, such as Al 2 0 3 , CuO, Fe 3 0 4 、TiO 2 , SiC. Commonly used base fluids (that is, the above-mentioned liquids) include water, oil, acetone, decene, etc.

[0003] Existing research applies nanofluids to the cooling of integrated circuits and electronic mechanical systems at the macro scale. In most existing studies, nanofluids are considered as single-phase fluids and it is assumed that nanoparticles are uniformly distributed in the base fluid. The most effective research method for single-phase nanofluids is to apply the research results on the flow and heat transfer of fluids in macro-scale models. However, the research results on macro-scale problems cannot be directly applied to micro-scale problems because as the scale decreases, the no-slip boundary conditions at the macro-scale are no longer applicable to the micro-scale.

[0004] In summary, the existing technology cannot apply nanofluids to micro-scale cooling.

[0005] Therefore, the prior art still needs to be improved and enhanced. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a method, device, equipment and medium for analyzing the heat transfer characteristics of nanofluids, which solves the problem that the prior art cannot apply nanofluids to micro-scale cooling.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a method for analyzing the heat transfer characteristics of a nanofluid, wherein the heat transfer characteristics include the flow velocity and average temperature of the nanofluid in a pipeline and the Nusselt number, including:

[0009] Obtaining a slip length between a micro-channel and the nanofluid, obtaining fluid property information of the nanofluid, and obtaining pipeline property information of the micro-channel, and applying a velocity calculation formula based on a power-law fluid model to the slip length, the fluid property information, and the pipeline property information to obtain a flow velocity of the nanofluid in the micro-channel;

[0010] determining an average temperature of the nanofluid in the microchannel based on the flow velocity;

[0011] Based on the average temperature, a Nusselt number of the nanofluid in the microchannel is determined.

[0012] In one implementation, applying a velocity calculation formula based on a power-law fluid model to the slip length, the fluid property information, and the pipeline property information to obtain the flow velocity of the nanofluid in the micro-pipeline includes:

[0013] Determining a flow index and a fluid consistency in the fluid property information;

[0014] Determining critical strain rate and wall strain rate and dimension data in the pipeline attribute information;

[0015] The slip length, the flow index, the fluid viscosity, the critical strain rate, the wall strain rate, and the size data are subjected to a velocity calculation formula based on a power-law fluid model to obtain the flow velocity of the nanofluid in the microchannel.

[0016] In one implementation, determining the average temperature of the nanofluid in the microchannel based on the flow velocity includes:

[0017] Obtaining a temperature distribution function of the nanofluid in a radial direction of the micro-channel, and obtaining a radius size of the micro-channel;

[0018] Multiplying the temperature distribution function by the flow velocity and then by a radius parameter to obtain a first integral term, and calculating a first integral value of the first integral term in a range from zero to the radius size;

[0019] Multiplying the flow velocity by a radius parameter to obtain a second integral term, and calculating a second integral value of the second integral term in a range from zero to the radius size;

[0020] The average temperature of the nanofluid in the microchannel is determined according to the first integral value and the second integral value.

[0021] In one implementation, determining the Nusselt number of the nanofluid in the microchannel based on the average temperature includes:

[0022] Obtaining a temperature distribution function of the nanofluid in a radial direction of the micro-channel, and obtaining a radius size of the micro-channel;

[0023] Performing differential calculation on the temperature distribution function with respect to a radius parameter to obtain a differential expression, and applying the differential expression to the radius size to obtain a differential value;

[0024] Determining the wall temperature of the nanofluid at the inner wall of the micro-channel;

[0025] The Nusselt number of the nanofluid in the microchannel is obtained according to the average temperature, the wall temperature and the differential value.

[0026] In one implementation, obtaining the Nusselt number of the nanofluid in the microchannel according to the average temperature, the wall temperature and the differential value includes:

[0027] Subtracting the average temperature from the wall temperature to obtain a temperature difference;

[0028] multiplying the differential value by the diameter of the micro-channel to obtain a product value;

[0029] The product value is divided by the temperature difference to obtain the Nusselt number of the nanofluid in the microchannel.

[0030] In one implementation, the speed calculation formula is constructed by:

[0031] Based on the power-law fluid model, determining the rheological properties of the nanofluid;

[0032] determining a slip boundary condition of the nanofluid;

[0033] A velocity calculation formula is constructed based on the rheological properties and the slip boundary conditions.

[0034] In one implementation, it also includes dimensionlessly processing the flow velocity, the average temperature, and the Nusselt number, respectively.

[0035] In a second aspect, an embodiment of the present invention further provides a device for analyzing heat transfer characteristics of a nanofluid, wherein the device comprises the following components:

[0036] a flow velocity calculation module, for obtaining a slip length between a micro-pipe and the nanofluid, and obtaining fluid property information of the nanofluid, and obtaining pipe property information of the micro-pipe, and applying a velocity calculation formula based on a power-law fluid model to the slip length, the fluid property information and the pipe property information to obtain a flow velocity of the nanofluid in the micro-pipe;

[0037] an average temperature calculation module, for determining an average temperature of the nanofluid in the micro-channel based on the flow velocity;

[0038] The Nusselt number calculation module is used to determine the Nusselt number of the nanofluid in the micro-channel based on the average temperature.

[0039] In a third aspect, an embodiment of the present invention further provides a terminal device, wherein the terminal device comprises a memory, a processor, and a nanofluid heat transfer characteristics analysis program stored in the memory and executable on the processor, and when the processor executes the nanofluid heat transfer characteristics analysis program, the steps of the nanofluid heat transfer characteristics analysis method described above are implemented.

[0040] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, on which a nanofluid heat transfer characteristics analysis program is stored. When the nanofluid heat transfer characteristics analysis program is executed by a processor, the steps of the nanofluid heat transfer characteristics analysis method described above are implemented.

[0041] Beneficial effect: The present invention constructs a velocity calculation formula based on a power-law fluid model, and then applies the velocity calculation formula to the slip length, fluid property information, and pipeline property information to obtain the flow velocity of the nanofluid in the micro-pipeline, and then calculates the average temperature of the nanofluid in the micro-pipeline based on the flow velocity, and finally calculates the Nusselt number of the nanofluid in the micro-pipeline based on the average temperature. The above-mentioned flow velocity, average temperature, and Nusselt number of the nanofluid are the heat transfer characteristics of the nanofluid. Since the power-law fluid model can describe the non-Newtonian characteristics of the nanofluid, and the non-Newtonian characteristics are applicable to the heat transfer characteristics of the nanofluid in the micro-pipeline, the flow velocity, average temperature, and Nusselt number of the present invention can describe the heat transfer characteristics of the nanofluid in the micro-pipeline, so that the present invention can apply the nanofluid to micro-scale cooling. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is the overall flow chart of the present invention;

[0043] Figure 2 A structural diagram of a device for analyzing the heat transfer characteristics of nanofluids provided by the present invention;

[0044] Figure 3 This is a block diagram of the internal structure principle of the terminal device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0045] The following is a clear and complete description of the technical solution of the present invention in combination with the embodiments and the accompanying drawings. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] Research has found that when nanoscale metal particles (the diameter of the metal particles is 1 to 100 nm) are doped into a liquid, a mixed liquid is formed. This mixed liquid is called a nanofluid. Nanoscale metal particles have a large relative surface area, which helps to enhance heat transfer. Moreover, since their geometric scale is closer to that of liquid molecules, they can remain suspended in the liquid for a long time and are not easy to precipitate. The nanoparticles commonly used to prepare nanofluids are divided into two categories: (1) metal particles, such as Cu, Al, Fe, Au, and Ag; (2) metal oxide particles, such as Al 2 0 3 , CuO, Fe 3 0 4 、TiO 2 , SiC. Commonly used base fluids (that is, the above-mentioned liquids) include water, oil, acetone, decene, etc.

[0047] Existing research applies nanofluids to the cooling of integrated circuits and electronic mechanical systems at the macro scale. In most existing studies, nanofluids are considered as single-phase fluids and it is assumed that nanoparticles are uniformly distributed in the base fluid. The most effective research method for single-phase nanofluids is to apply the research results on the flow and heat transfer of fluids in macro-scale models. However, the research results on macro-scale problems cannot be directly applied to micro-scale problems because as the scale decreases, the no-slip boundary conditions at the macro-scale are no longer applicable to the micro-scale.

[0048] In order to solve the above technical problems, the present invention provides a method, device, equipment and medium for analyzing the heat transfer characteristics of nanofluids, which solves the problem that the prior art cannot apply nanofluids to micro-scale cooling.

[0049] The heat transfer characteristic analysis method of a nanofluid in this embodiment can be applied to a terminal device, which can be a terminal product with a data processing function, such as a controller of a cooling device. Figure 1 As shown in , the heat transfer characteristics analysis method of the nanofluid specifically includes the following steps:

[0050] S100, obtaining a slip length between a micro-pipe and the nanofluid, obtaining fluid property information of the nanofluid, and obtaining pipe property information of the micro-pipe, and applying a velocity calculation formula based on a power-law fluid model to the slip length, the fluid property information, and the pipe property information to obtain a flow velocity of the nanofluid in the micro-pipe.

[0051] Microchannels are micrometer-scale channels. The heat transfer efficiency of nanofluids calculated using the power law fluid model is significantly higher than that calculated using the Newtonian fluid model.

[0052] S200: Determine an average temperature of the nanofluid in the microchannel based on the flow velocity.

[0053] S300: Determine the Nusselt number of the nanofluid in the microchannel based on the average temperature.

[0054] Step S100, step S200, and step S300 of this embodiment can calculate the heat transfer characteristics of nanofluids in micro-integrated circuits and micro-electro-mechanical systems, that is, placing nanofluids in micro-integrated circuits and micro-electro-mechanical systems, and cooling the micro-integrated circuits and micro-electro-mechanical systems through the thermal conductivity of metal particles in the nanofluids.

[0055] Embodiment 1: In this embodiment, the flow velocity of the nanofluid in the micro-channel is obtained by applying a velocity calculation formula based on a power-law fluid model to the slip length, the fluid property information and the channel property information in step S100, including the following specific steps S101, S102 and S103:

[0056] S101, determining the flow index n and the fluid viscosity m in the fluid property information.

[0057] The values ​​of the flow index n and the fluid consistency m are related to the volume of the nanoparticles and the concentration of the nanoparticles. The volume of the nanoparticles is the volume of the nanoscale metal particles, and the concentration of the nanoparticles is the concentration of the nanoscale metal particles in the nanofluid.

[0058] S102, determining the critical strain rate γ in the pipeline attribute information c and the wall strain rate γ w And size data.

[0059] The dimensional data include the radial coordinate r of the micro-channel * and the radius a of the micro-channel, the critical strain rate γ c is the critical strain rate at which the slip length bifurcates.

[0060] S103, the slip length The flow index n, the fluid consistency m, the critical strain rate γ c , the wall strain rate γ w The size data is applied to the velocity calculation formula constructed based on the power law fluid model to obtain the flow velocity u of the nanofluid in the micro-channel. * .

[0061]

[0062] p * is the pressure of the nanofluid, z * is the coordinate along the length direction of the micro-pipe (that is, the axial direction of the micro-pipe). * represents dimensionality, such as flow velocity u * is the dimensionalized flow velocity, flow velocity u * is the flow velocity of the nanofluid along the radial direction of the microchannel.

[0063] The above velocity calculation formula in this embodiment is constructed in the following manner: based on the power-law fluid model, the rheological properties of the nanofluid are determined; the slip boundary conditions of the nanofluid are determined; and based on the rheological properties and the slip boundary conditions, a velocity calculation formula is constructed.

[0064] Based on the power law fluid model, the rheological properties of the nanofluid are determined, and the rheological properties meet the following conditions:

[0065]

[0066] Slip boundary conditions:

[0067]

[0068] Combine the rheological property conditions and slip boundary conditions and in the radial r * We can get u by integrating * The speed calculation formula is:

[0069] This embodiment also determines the flow velocity u * The dimensionless processing is performed to obtain the dimensionless flow velocity u. The specific process is as follows:

[0070] When the formula (1) When it is much smaller than 1, let r in formula (1) * is equal to zero, so

[0071]

[0072] In the formula, k=n / (n+1),ρs are the slip radii of the nanofluids, and k is the coefficient.

[0073] Embodiment 2: In this embodiment, the step S200 of determining the average temperature of the nanofluid in the micro-channel based on the flow velocity includes the following specific steps S201, S202, S203, and S204:

[0074] S201, obtaining the radial direction r of the nanofluid along the micro-channel * The temperature distribution function in the direction T * , and obtain the radius dimension a of the micro-pipe.

[0075] T * =T·(T 0 -T w )+T w (2)

[0076] T w is the wall temperature, that is, the temperature of the nanofluid on the inner wall of the microchannel, T 0 is the temperature of the nanofluid at the inlet of the microchannel, T w and T 0 Satisfies the following relationship:

[0077] T * (0,r * )=T 0 ,T * (z * ,a)=T w

[0078]

[0079] A i is a constant, λ i is the eigenvalue, θ i (r) is the corresponding characteristic function, A in formula (3) i and θ i (r) is known, we only need to calculate λ i T can be calculated by formula (3), and then T can be substituted into formula (2) to obtain the expression of T*, that is, formula (1)

[0080] Solve λ by the following process i :

[0081] |M ij -λ 2 N ij |=0 (4)

[0082] in,

[0083]

[0084] Substituting formula (5) and formula (6) into formula (4) can calculate λ.

[0085] S202, the temperature distribution function T * Multiply by the flow velocity u * Multiply it by the radius parameter r * , and get the first integral term And calculate the first integral term The first integral value in the interval from zero to the radius a

[0086] S203, the flow velocity u * Multiply by the radius parameter r * , and get the second integral term And calculate the second integral value of the second integral term in the interval from zero to the radius size a

[0087] S204, determining an average temperature of the nanofluid in the micro-channel according to the first integral value and the second integral value

[0088]

[0089] This embodiment also calculates the average temperature The average temperature after dimensionless processing is T b :

[0090]

[0091] In the formula, r = ρ s r * / a.

[0092] Embodiment 3: In this embodiment, in step S300, the Nusselt number Nu of the nanofluid in the micro-channel is determined based on the average temperature. * , including the following specific steps S301 to S306:

[0093] S301, obtaining the radius r of the nanofluid along the micro-channel * The temperature distribution function T * , and obtain the radius dimension a of the micro-pipe.

[0094] This embodiment of T * and T in Example 2 *same.

[0095] S302, the temperature distribution function T * Perform differential calculations on the radius parameter and obtain the differential expression And apply the differential expression to the radius size to obtain the differential value

[0096] S303, determining the wall temperature T of the nanofluid at the inner wall of the micro-channel w :

[0097] T w =T * (z * ,a)

[0098] S304, the wall temperature T w Subtract the average temperature Get the temperature difference

[0099] S305: The differential value Multiply by the diameter of the micro-channel 2a to obtain the product value

[0100] S306, dividing the product value by the temperature difference to obtain the Nusselt number Nu of the nanofluid in the micro-channel * :

[0101]

[0102] This embodiment also calculates the Nusselt number Nu * After dimensionless processing, the Nusselt number Nu * For Nu:

[0103]

[0104] In practical applications, the flow velocity u * Related to the nanoparticle volume concentration φ, that is, the nanoparticle volume concentration φ affects the flow velocity u * This is because φ affects the flow index n and fluid consistency m in formula (1). The relationship between φ and n and m is shown in Table 1:

[0105] Table 1

[0106]

[0107]

[0108] The following is a specific example to illustrate the flow velocity u calculated using formula (1):* , when p * For 10 5 Pa / m and the nanoparticle volume concentration φ is 0%, 1%, 3%, and 5% respectively. * The positions along the direction (the first column in Table 2 is along the radius r * The flow velocity u of the nanofluid at each position in the direction * As shown in Table 2. For example, when p * For 10 5 Pa / m and the nanoparticle volume concentration φ is 0%, along the radius r * The flow velocity u at a distance of 0.0000001m from the center of the microtube cross section * It is 1.27E-05m / s.

[0109] Table 2

[0110]

[0111]

[0112] When p * For 10 6 Pa / m and the nanoparticle volume concentration φ is 0%, 1%, 3%, and 5% respectively. * The positions along the direction (the first column in Table 3 is along the radius r * The flow velocity u of the nanofluid at each position in the direction * As shown in Table 3:

[0113] Table 3

[0114]

[0115] When the radius a is 10 -6 m and slip length For 10 -8 The volume flow rate changes with the pressure gradient when the nanoparticle volume concentration φ is 0%, 1%, 3%, and 5% respectively -dp * The changes of / dz are shown in Table 4:

[0116] Table 4

[0117]

[0118] When the microtubule radius a is 10 -5 m, slip length For 10 -8 The changes of volume flow rate with pressure gradient when m and nanoparticle volume concentration φ are 0%, 1%, 3%, and 5% respectively are shown in Table 5:

[0119] Table 5

[0120]

[0121]

[0122] The nanoparticle volume concentration φ was fixed at 5%, and P was fixed at 2x10 6 Pam, calculate Nu with slip length As shown in Table 6, when the relative slip length and 0.1, the change of Nu in the axial direction. It can be seen that the local Nu number decreases with the increase of z value and eventually tends to a constant value. Corresponding to different slip lengths, it is shown that the length of the entrance section is basically unchanged. However, for any fixed z, Nu increases with the increase of nanoparticle concentration. This phenomenon can be explained by the change of the velocity of the nanofluid near the tube wall. From the theoretical analysis, it can be seen that if the pressure gradient and the concentration of nanoparticles are assumed to be unchanged, the flow velocity at the wall will increase with the increase of the slip length, that is, a larger slip length can promote the flow of nanofluids on the boundary and thus enhance heat transfer. It can be concluded that the increase in slip length can improve the heat transfer efficiency of nanofluids in microtubes.

[0123] Table 6

[0124]

[0125]

[0126] The variation of Nusselt number with relative slip length of the fully developed section of nanofluids with φ = 0, 1%, 3%, and 5% under two different boundary conditions of equal wall temperature and equal heat flow. It can be found from Table 7 that the heat transfer efficiency of the fully developed section of nanofluids under both boundary conditions increases with the increase of particle concentration, slip particle concentration, slip length, and nanometer length under equal heat flow boundary conditions. For a fixed fluid, the heat transfer efficiency is higher than that under the boundary condition of equal wall temperature. In addition, for each fixed particle concentration, the distance between the two curves corresponding to the two different boundary conditions increases with the increase of slip length.

[0127] Table 7

[0128]

[0129]

[0130] This embodiment also provides a device for analyzing the heat transfer characteristics of nanofluids, such as Figure 2 As shown, the device comprises the following components:

[0131] A flow velocity calculation module 01 is used to obtain the slip length between the micro-pipe and the nanofluid, obtain the fluid property information of the nanofluid, and obtain the pipeline property information of the micro-pipe, and apply a velocity calculation formula based on a power-law fluid model to the slip length, the fluid property information, and the pipeline property information to obtain the flow velocity of the nanofluid in the micro-pipe;

[0132] An average temperature calculation module 02, used to determine the average temperature of the nanofluid in the micro-channel based on the flow velocity;

[0133] The Nusselt number calculation module 03 is used to determine the Nusselt number of the nanofluid in the micro-channel based on the average temperature.

[0134] Based on the above embodiments, the present invention further provides a terminal device, whose principle block diagram can be shown as follows: Figure 3 As shown. The terminal device includes a processor, a memory, a network interface, and a display screen connected through a system bus. Among them, the processor of the terminal device is used to provide computing and control capabilities. The memory of the terminal device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The network interface of the terminal device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a method for analyzing the heat transfer characteristics of a nanofluid is implemented. The display screen of the terminal device can be a liquid crystal display screen or an electronic ink display screen.

[0135] Those skilled in the art will understand that Figure 3 The principle block diagram shown in the figure is only a block diagram of a partial structure related to the scheme of the present invention, and does not constitute a limitation on the terminal device to which the scheme of the present invention is applied. The specific terminal device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0136] In one embodiment, a terminal device is provided. The terminal device includes a memory, a processor, and a nanofluid heat transfer characteristic analysis method program stored in the memory and executable on the processor. When the processor executes the nanofluid heat transfer characteristic analysis method program, the following operation instructions are implemented:

[0137] Obtaining a slip length between a micro-channel and the nanofluid, obtaining fluid property information of the nanofluid, and obtaining pipeline property information of the micro-channel, and applying a velocity calculation formula based on a power-law fluid model to the slip length, the fluid property information, and the pipeline property information to obtain a flow velocity of the nanofluid in the micro-channel;

[0138] determining an average temperature of the nanofluid in the microchannel based on the flow velocity;

[0139] Based on the average temperature, a Nusselt number of the nanofluid in the microchannel is determined.

[0140] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided by the present invention can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0141] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for analyzing the heat transfer characteristics of a nanofluid, wherein the heat transfer characteristics include the flow velocity, average temperature and Nusselt number of the nanofluid in a pipeline, characterized in that: include: Obtaining a slip length between a micro-channel and the nanofluid, obtaining fluid property information of the nanofluid, and obtaining pipeline property information of the micro-channel, and applying a velocity calculation formula based on a power-law fluid model to the slip length, the fluid property information, and the pipeline property information to obtain a flow velocity of the nanofluid in the micro-channel; determining an average temperature of the nanofluid in the microchannel based on the flow velocity; Based on the average temperature, a Nusselt number of the nanofluid in the microchannel is determined.

2. The method for analyzing the heat transfer characteristics of nanofluids according to claim 1, characterized in that: Applying a velocity calculation formula based on a power-law fluid model to the slip length, the fluid property information, and the pipeline property information to obtain the flow velocity of the nanofluid in the micro-pipeline includes: Determining a flow index and a fluid consistency in the fluid property information; Determining critical strain rate and wall strain rate and dimension data in the pipeline attribute information; The slip length, the flow index, the fluid viscosity, the critical strain rate, the wall strain rate, and the size data are subjected to a velocity calculation formula based on a power-law fluid model to obtain the flow velocity of the nanofluid in the microchannel.

3. The method for analyzing the heat transfer characteristics of nanofluids according to claim 1, characterized in that: Determining an average temperature of the nanofluid in the microchannel based on the flow velocity comprises: Obtaining a temperature distribution function of the nanofluid in a radial direction of the micro-channel, and obtaining a radius size of the micro-channel; Multiplying the temperature distribution function by the flow velocity and then by a radius parameter to obtain a first integral term, and calculating a first integral value of the first integral term in a range from zero to the radius size; Multiplying the flow velocity by a radius parameter to obtain a second integral term, and calculating a second integral value of the second integral term in a range from zero to the radius size; The average temperature of the nanofluid in the microchannel is determined according to the first integral value and the second integral value.

4. The method for analyzing the heat transfer characteristics of nanofluids according to claim 1, characterized in that: Determining the Nusselt number of the nanofluid in the microchannel based on the average temperature includes: Obtaining a temperature distribution function of the nanofluid in a radial direction of the micro-channel, and obtaining a radius size of the micro-channel; Performing differential calculation on the temperature distribution function with respect to a radius parameter to obtain a differential expression, and applying the differential expression to the radius size to obtain a differential value; Determining the wall temperature of the nanofluid at the inner wall of the micro-channel; The Nusselt number of the nanofluid in the microchannel is obtained according to the average temperature, the wall temperature and the differential value.

5. The method for analyzing the heat transfer characteristics of nanofluids according to claim 4, characterized in that: According to the average temperature, the wall temperature and the differential value, the Nusselt number of the nanofluid in the micro-channel is obtained, including: Subtracting the average temperature from the wall temperature to obtain a temperature difference; multiplying the differential value by the diameter of the micro-channel to obtain a product value; The product value is divided by the temperature difference to obtain the Nusselt number of the nanofluid in the microchannel.

6. The method for analyzing the heat transfer characteristics of a nanofluid according to any one of claims 1 to 5, characterized in that: The construction method of the speed calculation formula includes: Based on the power-law fluid model, determining the rheological properties of the nanofluid; determining a slip boundary condition of the nanofluid; A velocity calculation formula is constructed based on the rheological properties and the slip boundary conditions.

7. The method for analyzing the heat transfer characteristics of a nanofluid according to any one of claims 1 to 5, characterized in that: The method also includes dimensionlessly processing the flow velocity, the average temperature, and the Nusselt number respectively.

8. A device for analyzing the heat transfer characteristics of nanofluids, characterized in that: The device comprises the following components: A flow velocity calculation module, used to obtain a slip length between a micro-pipe and the nanofluid, obtain fluid property information of the nanofluid, and obtain pipe property information of the micro-pipe, and apply a velocity calculation formula based on a power-law fluid model to the slip length, the fluid property information, and the pipe property information to obtain a flow velocity of the nanofluid in the micro-pipe; an average temperature calculation module, for determining an average temperature of the nanofluid in the micro-channel based on the flow velocity; The Nusselt number calculation module is used to determine the Nusselt number of the nanofluid in the micro-channel based on the average temperature.

9. A terminal device, characterized in that: The terminal device includes a memory, a processor, and a nanofluid heat transfer characteristics analysis program stored in the memory and executable on the processor. When the processor executes the nanofluid heat transfer characteristics analysis program, the steps of the nanofluid heat transfer characteristics analysis method as described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a nanofluid heat transfer characteristic analysis program, and when the nanofluid heat transfer characteristic analysis program is executed by the processor, the steps of the nanofluid heat transfer characteristic analysis method according to any one of claims 1 to 7 are implemented.

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