Improved method, device and electronic equipment for measuring thermal conductivity of non-newtonian fluids

Abstract

This invention relates to an improved method, apparatus, and electronic device for measuring the thermal conductivity of non-Newtonian fluids. The method includes: constructing a non-Newtonian fluid thermal conductivity measurement platform; establishing a thermal conductivity model for the non-Newtonian fluid, considering the radial variation of viscous heat dissipation transmitted through the annular gap of the measurement platform during the model establishment process; preparing the non-Newtonian fluid; using the measurement platform to measure the thermal conductivity of the non-Newtonian fluid to obtain experimental data; and substituting the experimental data into the thermal conductivity model to calculate the improved thermal conductivity of the non-Newtonian fluid. This invention improves upon existing methods for measuring the thermal conductivity of non-Newtonian fluids by considering the radial variation of viscous heat dissipation transmitted through the annular gap of the coaxial cylinder during the establishment of the thermal conductivity model, thus making the measurement of thermal conductivity more accurate.

Description

Technical Field

[0001] This invention relates to the technical field of thermal conductivity measurement, and specifically to an improved method, apparatus, and electronic device for measuring the thermal conductivity of non-Newtonian fluids. Background Technology

[0002] Clarifying the thermal conductivity of non-Newtonian fluids is crucial for studying their complex mass-energy transport characteristics. The shearing motion of non-Newtonian fluids disrupts their internal microstructure, resulting in non-Newtonian rheological and thermal conduction properties; that is, the thermal conductivity changes significantly with the shear rate. Previous studies on the thermal conductivity of non-Newtonian fluids under shear flow conditions mostly employed the coaxial cylinder method. For example, Professor Sun Chengzhen et al. of Xi'an Jiaotong University (Sun C, Bai B, Lu WQ, et al. Shear-rate dependent effective thermal conductivity of H2O+SiO2 nanofluids[J]. Physics of Fluids, 2013, 25(5):718.) used the coaxial cylinder method to measure the thermal conductivity of silica nanofluids under varying shear rates. Xu Hongpeng's master's thesis at Harbin Institute of Technology (Xu Hongpeng. Rheological Properties of Viscoelastic Fluid-Based Nanofluids[D]. Harbin Institute of Technology, 2013.) used the coaxial cylinder method to study the thermal conductivity of viscoelastic fluid-based nanofluids under different shear rates. However, these scholars neglected the viscous heat dissipation generated during shear flow, resulting in measured thermal conductivity values ​​that were lower than the true values.

[0003] In his doctoral dissertation (Sui Jize. Study on heat and mass transfer in shear flow of complex fluid boundary layer [D]. Beijing University of Science and Technology, 2017.), Dr. Sui Jize of Beijing University of Science and Technology studied the thermal conductivity of power-law non-Newtonian fluids dependent on shear rate, taking into account the contribution of hydrodynamic flow field. His design of the coaxial cylindrical thermal conductivity measuring instrument considered the heating and rotation of the outer cylinder, with heat transferred from the outer cylinder to the inner cylinder through the experimental fluid. This made it difficult for the accumulated heat transferred to the inner cylinder to dissipate outward, resulting in inaccurate measurement. At the same time, the contribution of hydrodynamics considered in the derivation of the thermal conductivity measurement formula was higher than the actual value. In his master's thesis (Liu Xiaochuan. Numerical and experimental study on boundary layer flow and heat transfer of power-law fluids [D]. [Sl]: Beijing University of Science and Technology, 2018.), Liu Xiaochuan of Beijing University of Science and Technology also studied the thermal conductivity characteristics of power-law fluids dependent on shear rate. He improved the thermal conductivity measurement equipment of Dr. Sui Jize, considering the rotation of the outer cylinder and the heating of the inner cylinder, and the outer cylinder being placed in a circulating water bath. In this way, the heat transferred from the inner cylinder can be carried away by the circulating water bath. However, the circulating water in the circulating water bath tank he designed is directly exposed to the environment, and it is impossible to avoid the interference of room temperature on the temperature of the circulating water.

[0004] Existing methods for measuring the thermal conductivity of non-Newtonian fluids, such as Chinese patent "A Method for Measuring the Thermal Conductivity of Non-Newtonian Fluids" (publication number CN 113075254 A), use the coaxial cylinder method to measure the thermal conductivity of non-Newtonian fluids. The design of the measuring equipment compensates for the above-mentioned defects and considers the viscous heat dissipation generated during fluid shear flow. However, it ignores the fact that the transmission of viscous heat dissipation in the annular gap varies with the radius of the annular gap. It simply treats the viscous heat dissipation transmitted in the annular gap as all the viscous heat dissipation generated in the entire gap, resulting in an overestimation of the measured value. Summary of the Invention

[0005] The purpose of this invention is to address the problem that existing methods for measuring the thermal conductivity of non-Newtonian fluids neglect the variation of viscous heat dissipation in the annular gap with radius, leading to inflated measured values. This invention proposes an improved method, apparatus, and electronic device for measuring the thermal conductivity of non-Newtonian fluids to solve the aforementioned problems in the prior art.

[0006] The above-mentioned technical objectives of the present invention will be achieved through the technical solutions described below.

[0007] An improved method for measuring the thermal conductivity of a non-Newtonian fluid, the method comprising the following steps:

[0008] S1. Construct a platform for measuring the thermal conductivity of non-Newtonian fluids;

[0009] S2. Establish a thermal conductivity model for non-Newtonian fluids, taking into account the radial variation of viscous heat dissipation transmitted in the annular gap of the measurement platform during the model establishment process;

[0010] S3. Prepare the non-Newtonian fluid;

[0011] S4. The thermal conductivity of the non-Newtonian fluid is measured using the aforementioned measurement platform to obtain experimental data;

[0012] S5. Substitute the experimental data into the thermal conductivity model to calculate the improved non-Newtonian fluid thermal conductivity.

[0013] In addition to the aspects and any possible implementations described above, a further implementation is provided in which the measuring platform includes two coaxial cylindrical heating and rotating units, each comprising an inner cylinder and an outer cylinder, a heating film being disposed on the inner wall of the inner cylinder, and a radial annular gap being formed between the inner cylinder and the outer cylinder.

[0014] In addition to the aspects and any possible implementations described above, a further implementation is provided, wherein the established thermal conductivity model is:

[0015]

[0016] Where k is the thermal conductivity of the non-Newtonian fluid;

[0017] r is the radius at a point in the annular gap, and r is the distance from the center point of the inner cylinder to a point in the liquid being measured at the same height. The value of r is determined by R. i To R o change;

[0018] Q1 represents the heat generated by heating the inner cylinder per unit time.

[0019] Q3 represents the amount of viscous heat loss generated per unit time during non-Newtonian fluid shear flow that is transferred at the position of the annular gap radius r.

[0020] R o The inner diameter of the outer cylinder;

[0021] R i The outer diameter of the inner cylinder;

[0022] T o The temperature of the non-Newtonian fluid close to the inner wall of the outer cylinder;

[0023] T i The temperature of the non-Newtonian fluid close to the outer wall of the inner cylinder;

[0024] h is the length of the inner cylinder heating film;

[0025] τ rθ It is shear stress. It is the shear rate of the fluid.

[0026] In addition to the aspects described above and any possible implementations, a further implementation is provided in which the thermal conductivity measurement is performed under different temperature gradients, shear rates, and concentration conditions.

[0027] In addition to the aspects described above and any possible implementations, a further implementation is provided in which the approximate expression for the temperature gradient is:

[0028] In addition to the aspects described above and any possible implementations, a further implementation is provided in which the expression for Q3 is: That is, the amount of heat transferred by viscous heat loss varies with the radius r.

[0029] In addition to the aspects described above and any possible implementations, a further implementation is provided in which the shear rate expression of the non-Newtonian fluid is approximated as: Where n is the rotational speed of the outer cylinder.

[0030] As described above, and in any possible implementation, a further implementation is provided, wherein the shear stress τ rθ The shear rate corresponding to the rotational speed n of the outer cylinder and the temperature at (T) i +T o The shear stress of the non-Newtonian fluid measured at ) / 2.

[0031] This invention provides an improved device for measuring the thermal conductivity of non-Newtonian fluids, the device being used to implement the method described, the device comprising:

[0032] A module is built to construct a platform for measuring the thermal conductivity of non-Newtonian fluids.

[0033] The modeling module is used to establish a thermal conductivity model for non-Newtonian fluids, taking into account the radial variation of viscous heat dissipation transmitted in the annular gap of the measurement platform during the model establishment process.

[0034] A preparation module is used to prepare the non-Newtonian fluid;

[0035] The measurement module is used to measure the thermal conductivity of the non-Newtonian fluid using the measurement platform to obtain experimental data.

[0036] The calculation module substitutes the experimental data into the thermal conductivity model to calculate the improved non-Newtonian fluid thermal conductivity.

[0037] The present invention also provides an electronic device, the computer device including a processor and a memory, the memory storing a computer program, the computer program being loaded and executed by the processor to implement the method.

[0038] Beneficial technical effects of the present invention

[0039] The improved method for measuring the thermal conductivity of non-Newtonian fluids of the present invention includes the following steps: constructing a non-Newtonian fluid thermal conductivity measurement platform; establishing a thermal conductivity model for the non-Newtonian fluid, considering the radial variation of viscous heat dissipation transmitted in the annular gap of the measurement platform during the model establishment process; preparing the non-Newtonian fluid; using the measurement platform to measure the thermal conductivity of the non-Newtonian fluid to obtain experimental data; and substituting the experimental data into the thermal conductivity model to calculate the improved thermal conductivity of the non-Newtonian fluid. This invention improves upon existing methods for measuring the thermal conductivity of non-Newtonian fluids by considering the radial variation of viscous heat dissipation transmitted in the annular gap of the coaxial cylinder during the establishment of the thermal conductivity model, thus making the measurement of thermal conductivity more accurate. Attached Figure Description

[0040] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings, wherein:

[0041] Figure 1 This is a schematic diagram of the method flow of the present invention. Detailed Implementation

[0042] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments, but the implementation of the present invention is not limited thereto.

[0043] like Figure 1 As shown in the embodiment of the present invention, an improved method for measuring the thermal conductivity of a non-Newtonian fluid is provided, comprising the following steps:

[0044] Step 1. Construct a platform for measuring the thermal conductivity of non-Newtonian fluids;

[0045] Step 2. Establish a thermal conductivity model for non-Newtonian fluids, taking into account the radial variation of viscous heat dissipation transmitted in the annular gap during the establishment of the thermal conductivity model; the annular gap refers to the radial gap between the inner and outer cylinders in the experimental equipment.

[0046] Step 3. Prepare the non-Newtonian fluid;

[0047] Step 4. Using the measurement platform built in step S1, the thermal conductivity of the non-Newtonian fluid prepared in step S3 is measured under different temperature gradients, shear rates, concentrations, and other conditions to obtain experimental data.

[0048] Step 5. Substitute the experimental data into the thermal conductivity model to calculate the thermal conductivity;

[0049] The thermal conductivity measurement platform constructed in step 1 is existing equipment, comprising: two coaxial cylindrical heating and rotating units, a low-temperature constant-temperature bath, a servo motor, a main control chassis, a computer module, and a circulating water bath. The two coaxial cylindrical heating and rotating units are centrally located within the circulating water bath, and the low-temperature constant-temperature bath is connected to the circulating water bath for cooling the liquid inside. The servo motor is connected to the two coaxial cylindrical heating and rotating units to drive the rotation of the outer cylinder and the lifting and lowering of the inner cylinder. One end of the main control chassis is electrically connected to the two coaxial cylindrical heating and rotating units, and the other end is connected to the computer module.

[0050] The dual-coaxial cylindrical heating and rotating unit comprises an inner cylinder and an outer cylinder placed coaxially, with a space between them to accommodate the non-Newtonian fluid to be measured. A heating film is attached to the inner wall of the inner cylinder, heated by low-voltage DC electricity. The heating power of the heating film is controlled by adjusting the voltage, thus heating the non-Newtonian fluid close to the outer wall of the inner cylinder. To ensure uniform heating of the non-Newtonian fluid, the length of the heating film is the same as the height of the inner cylinder. The main body material of both the inner and outer cylinders is copper, with the inner cylinder being 4mm thick and the outer cylinder 2mm thick. The bottom gap between the inner and outer cylinders is 1mm. The radial gap between the inner and outer cylinders to accommodate the non-Newtonian fluid is 2mm. The outer sides and lid of the circulating water bath are covered with an insulation layer. Two thermistors are welded and encapsulated at symmetrical positions at different heights on the outer wall of the inner cylinder to measure the temperature of the non-Newtonian fluid close to the outer wall of the inner cylinder. Six resistance thermometers (RTDs) are welded and encapsulated near the outer wall of the circulating water bath. Three RTDs are welded and encapsulated at 120° intervals on each of two different circumferences at different heights, used to approximate the temperature of non-Newtonian fluids near the inner wall of the outer cylinder. Polytetrafluoroethylene (PTFE) insulation material is installed at the top and bottom of the outer cylinder, and at the top, bottom, and center of the inner cylinder. Air is placed in the gap between the insulation material at the center of the inner cylinder and the inner wall. The main control chassis includes a control module and a data acquisition module. The temperature signal output of the inner cylinder RTDs is connected to the inner cylinder temperature signal input of the data acquisition module; the temperature signal output of the outer cylinder RTDs is connected to the outer cylinder temperature signal input of the data acquisition module; the temperature signal output of the data acquisition module is connected to the temperature signal input of the computer module; the control signal output of the computer module is connected to the signal input of the control module; and the signal output of the control module is connected to the control signal input of the servo motor. During the experimental measurement, the inner cylinder is heated to test the non-Newtonian fluid, while the outer cylinder rotates under the drive of a servo motor. The heat generated by the heating film in the inner cylinder and the viscous heat dissipation generated by the fluid shear flow are transferred to the outer cylinder through the non-Newtonian fluid. The heat is then carried away by the circulating water in the circulating water bath. When the temperature of the inner and outer cylinders measured by the thermal resistance no longer changes, a steady-state rotating Cuyet flow field is formed.

[0051] After the measurement platform was set up, the outer diameter R of the inner cylinder was... i and the inner diameter R of the outer cylinder o The length h of the inner cylinder heating film can be obtained. The non-Newtonian fluid thermal conductivity measurement platform measures the temperature of the inner cylinder and the temperature of the outer cylinder when the flow of non-Newtonian fluid between two coaxial cylinders reaches a steady state.

[0052] Preferably, in step 2, considering the radial variation of viscous heat dissipation transmitted in the annular gap of the coaxial cylinder, the non-Newtonian fluid thermal conductivity model is established as follows:

[0053]

[0054] Where k is the thermal conductivity of the non-Newtonian fluid;

[0055] r is the radius at a point in the annular gap, and r is the distance from the center point of the inner cylinder to a point in the liquid being measured at the same height. The value of r is determined by R. i To R o change;

[0056] Q1 represents the heat generated per unit time by the heating film on the inner cylinder;

[0057] Q3 represents the amount of viscous heat dissipation generated per unit time during non-Newtonian fluid shear flow at the radius r of the annular gap, and its expression is: The expression shows that the amount of heat transferred by viscous heat loss varies with the radius r.

[0058] R o The inner diameter of the outer cylinder;

[0059] R i The outer diameter of the inner cylinder;

[0060] T o The temperature of the non-Newtonian fluid close to the inner wall of the outer cylinder;

[0061] T i The temperature of the non-Newtonian fluid close to the outer wall of the inner cylinder;

[0062] h is the length of the heating film on the inner wall of the inner cylinder.

[0063] The specific process of establishing the thermal conductivity model in step 2 is as follows:

[0064] Based on existing non-Newtonian fluid thermal conductivity measurement platforms, if the annular gap between the inner and outer cylinders is filled with a non-Newtonian fluid, the inner cylinder is heated, and the rotation of the outer cylinder causes the non-Newtonian fluid to undergo shear flow, then the energy equation of the non-Newtonian fluid in steady state in cylindrical coordinates is:

[0065]

[0066] In this equation, the first term on the left is the thermal conductivity term, and the second term is the viscous dissipation term. r is the radius, the distance from the center point of the inner cylinder to a point in the liquid at the same height; k is the thermal conductivity of the non-Newtonian fluid; T is the temperature of the non-Newtonian fluid; u θ It is the tangential velocity of a non-Newtonian fluid; τ rθ It is the shear stress of a non-Newtonian fluid.

[0067] The fluid shear rate in cylindrical coordinates is expressed as:

[0068]

[0069] Therefore, the energy equation can also be written as:

[0070]

[0071] Ignoring the change in shear rate within the annular gap, the shear rate Approximately:

[0072]

[0073] In the formula, n is the rotational speed of the outer cylinder. R o It is the inner diameter of the outer cylinder; R i It refers to the outer diameter of the inner cylinder; the heat transferred from the inner cylinder to the outer cylinder includes not only the heat generated per unit time by the heating film on the inner cylinder, but also the viscous heat loss generated by the fluid shear flow. This refers to the viscous heat dissipation generated by the shear flow of the fluid along the θ direction per unit volume and per unit time. The total viscous heat dissipation generated by the fluid from the outer wall of the inner cylinder to the radius r per unit time is the viscous heat dissipation generated in the entire annular gap minus the viscous heat dissipation generated from the radius r to the inner wall of the outer cylinder.

[0074]

[0075] in The viscous heat dissipation generated throughout the entire annular gap is denoted by Q3, which refers to the viscous heat dissipation generated from the outer wall of the inner cylinder to the radius r of the annular gap. This excludes the viscous heat dissipation generated within the annular gap from radius r to the inner wall of the outer cylinder. As can be seen from the expression (5) for Q3, it is related to the radius r and varies with it. This is the volume of the annular gap from radius r to the inner wall of the outer cylinder. At thermal equilibrium, the total heat passing through the cylindrical side at radius r within the annular gap is the heat Q1 generated by heating the inner cylinder plus the viscous heat loss from the outer wall of the inner cylinder to radius r, i.e.:

[0076]

[0077] Where Q1 is the heat generated by the heating film of the inner cylinder per unit time; Q2 is the viscous heat loss generated in the entire annular gap; Q3 is the viscous heat loss generated in the annular gap from the outer wall of the inner cylinder to the radius r position, and also the viscous heat loss through the cylindrical side at the radius r position. It can be seen from the formula that the viscous heat loss through the radius r position varies with the radius r.

[0078] Since both viscous heat loss and heat generated by inner cylinder heating are transferred through heat conduction, if we consider viscous heat loss as heat generated by inner cylinder heating, then at thermal equilibrium:

[0079]

[0080] Integrating both sides of equation (7) simultaneously, we have:

[0081]

[0082] Where h is the length of the heating film; substituting into formula (6) into formula (8) yields:

[0083]

[0084] From R i To R o Integral formula (9) yields:

[0085]

[0086] Solving the integral equation (10), the thermal conductivity considering viscous heat dissipation is:

[0087]

[0088] Where T o It is the temperature of the fluid close to the inner wall of the outer cylinder, measured by six thermal resistors installed on the circulating water bath near the outer wall of the outer cylinder, and is the average of the six measured temperatures; T i τ is the temperature of the non-Newtonian fluid close to the outer wall of the inner cylinder, measured by two thermistors mounted on the inner cylinder, and is the average of the two measured temperatures; rθ It is shear stress, measured by a commercial rheometer; It is the shear rate of the fluid.

[0089] Step 3. The specific process for preparing the non-Newtonian fluid solution is as follows:

[0090] Non-Newtonian fluids are widely found in daily life and production. Examples include egg liquid, shampoo, and polymer solutions. A specific concentration of non-Newtonian fluid can be prepared as needed, and its thermal conductivity can be measured. For instance, to obtain the thermal conductivity of a hydroxyethyl cellulose aqueous solution, a certain amount of hydroxyethyl cellulose is added to deionized water and stirred thoroughly until completely dissolved, resulting in a hydroxyethyl cellulose aqueous solution, which is a non-Newtonian fluid.

[0091] Step 4. Using the measurement platform built in step S1, measure the thermal conductivity of the non-Newtonian fluid prepared in step S3 under different temperature gradients, shear rates, concentrations, etc., to obtain experimental data; the specific steps for measuring thermal conductivity are as follows:

[0092] (1) Fill the gap between the inner and outer cylinders with the non-Newtonian fluid to be measured, and the height of the non-Newtonian fluid is the same as the height of the inner cylinder.

[0093] (2) Set the temperature of the circulating water in the circulating water bath, turn on the low temperature constant temperature bath, and wait for the temperature to reach the set value and for the inner and outer cylinders to be the same.

[0094] (3) Set the rotation speed n of the outer cylinder, turn on the servo motor, and make the outer cylinder start to rotate;

[0095] (4) Set the heating power Q1 to start heating the inner cylinder heating film. In order to avoid radial convection, the temperature difference between the inner cylinder and the outer cylinder should not be too large. Therefore, the set heating power should not be too large. It is best to ensure that the temperature difference between the inner cylinder and the outer cylinder does not exceed 10℃ when thermal equilibrium is reached.

[0096] (5) When steady state is reached, record the temperatures of the inner and outer cylinders, and the temperature of the inner cylinder T. i The average of two temperatures measured by two thermometers welded and sealed inside the outer wall of the inner cylinder is approximately equal to the temperature T of the outer cylinder. o The average of six temperatures measured by six thermal resistors installed on the circulating water bath is approximated;

[0097] (6) Use the average temperature of the inner and outer cylinders (T) i +T o Approximate the temperature of a non-Newtonian fluid with π / 2, and calculate the shear rate corresponding to the rotational velocity n. The existing rheometer was used to measure the non-Newtonian fluid under test at a temperature of (T). i +T o ) / 2 and shear rate is Shear stress τ at time rθ A rheometer is an instrument for measuring the rheological properties of fluids, such as the viscosity and shear stress of fluids at different shear rates and temperatures.

[0098] (7) Calculate the thermal conductivity of the non-Newtonian fluid solution to be tested using formula (11). If you need to measure the thermal conductivity at different shear rates, repeat from item (3) and change the rotation speed of the outer cylinder; if you need to measure the thermal conductivity of the non-Newtonian fluid at different concentrations, repeat from item (1), remove the old liquid and add a new volume fraction or mass fraction of the solution to be tested; if you need to measure the thermal conductivity under different temperature gradients, repeat from item (2), readjust the circulating water bath temperature and heating power so that the temperature difference between the inner and outer cylinders changes when the steady state is reached, i.e., the temperature gradient. However, when studying the change of thermal conductivity with temperature gradient, the fluid temperature must be kept constant, that is, the average temperature of the inner and outer cylinders at the end of each measurement when steady state is reached (T). i +T o ) / 2 remains unchanged.

[0099] As an embodiment of the present invention, the present invention also discloses an improved device for measuring the thermal conductivity of non-Newtonian fluids, the device being used to implement the method described, the device comprising:

[0100] A module is built to construct a platform for measuring the thermal conductivity of non-Newtonian fluids.

[0101] The modeling module is used to establish a thermal conductivity model for non-Newtonian fluids, taking into account the radial variation of viscous heat dissipation transmitted in the annular gap of the measurement platform during the model establishment process.

[0102] A preparation module is used to prepare the non-Newtonian fluid;

[0103] The measurement module is used to measure the thermal conductivity of the non-Newtonian fluid using the measurement platform to obtain experimental data.

[0104] The calculation module substitutes the experimental data into the thermal conductivity model to calculate the improved non-Newtonian fluid thermal conductivity.

[0105] As an embodiment of the present invention, the present invention also provides an electronic device, the computer device including a processor and a memory, the memory storing a computer program, the computer program being loaded and executed by the processor to implement the method described in the present invention.

[0106] The foregoing description illustrates and describes several preferred embodiments of the present invention. However, as previously stated, it should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the inventive concept described herein through the foregoing teachings or techniques or knowledge in related fields. Any modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. An improved method for measuring the thermal conductivity of a non-Newtonian fluid, characterized in that, The method includes the following steps: S1. Construct a non-Newtonian fluid thermal conductivity measurement platform, the measurement platform including two coaxial cylindrical heating and rotating units, the two coaxial cylindrical heating and rotating units including an inner cylinder and an outer cylinder, the inner wall of the inner cylinder is provided with a heating film, and a radial annular gap is formed between the inner cylinder and the outer cylinder; S2. Establish a thermal conductivity model for the non-Newtonian fluid. During the establishment of this model, the radial variation of viscous heat dissipation transmitted through the annular gap of the measurement platform is considered. The established thermal conductivity model is as follows: in, The thermal conductivity of the non-Newtonian fluid is given. Let be the radius at a point in the annular gap, and let be the distance from the center point of the inner cylinder to a point in the liquid being measured at the same height. The magnitude of is determined by... to change; The heat generated per unit time when the inner cylinder is heated; The viscous heat dissipation generated per unit time during the shear flow of a non-Newtonian fluid is measured in the radius of the annular gap. The amount of data transferred at the location; The inner diameter of the outer cylinder; The outer diameter of the inner cylinder; The temperature of the non-Newtonian fluid close to the inner wall of the outer cylinder; The temperature of the non-Newtonian fluid close to the outer wall of the inner cylinder; It is the length of the inner cylinder heating film; It is shear stress. It is the shear rate of the fluid; The The expression is: That is, the amount of heat transferred by viscous heat dissipation varies with radius. It changes with the changes; The expression for the shear rate is approximately: ,in The rotational speed of the outer cylinder; S3. Prepare the non-Newtonian fluid; S4. The thermal conductivity of the non-Newtonian fluid is measured using the aforementioned measurement platform to obtain experimental data; S5. Substitute the experimental data into the thermal conductivity model to calculate the improved non-Newtonian fluid thermal conductivity.

2. The improved method for measuring the thermal conductivity of non-Newtonian fluids according to claim 1, characterized in that, The thermal conductivity was measured under different temperature gradients, shear rates, and concentrations.

3. The improved method for measuring the thermal conductivity of non-Newtonian fluids according to claim 2, characterized in that, The approximate expression for the temperature gradient is: .

4. The improved method for measuring the thermal conductivity of non-Newtonian fluids according to claim 1, characterized in that, The shear stress For the rotational speed of the outer cylinder The corresponding shear rate and temperature at The shear stress of the non-Newtonian fluid was measured at that time.

5. An improved device for measuring the thermal conductivity of non-Newtonian fluids, characterized in that, The apparatus is used to implement the method according to any one of claims 1-4, the apparatus comprising: A module is built to construct a platform for measuring the thermal conductivity of non-Newtonian fluids. The modeling module is used to establish a thermal conductivity model for non-Newtonian fluids, taking into account the radial variation of viscous heat dissipation transmitted in the annular gap of the measurement platform during the establishment of the thermal conductivity model. A preparation module is used to prepare the non-Newtonian fluid; The measurement module is used to measure the thermal conductivity of the non-Newtonian fluid using the measurement platform to obtain experimental data. The calculation module substitutes the experimental data into the thermal conductivity model to calculate the improved non-Newtonian fluid thermal conductivity.

6. An electronic device, characterized in that, The electronic device includes a processor and a memory, the memory storing a computer program that is loaded and executed by the processor to implement the method as described in any one of claims 1 to 4.

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