Metal microreactor surface temperature testing method based on digital twinborn technology

Abstract

The invention discloses a metal microreactor surface temperature testing method based on a digital twinning technology, and relates to the technical field of metering calibration. The method comprises the following steps: establishing a geometric model according to the actual geometric size and the internal structure of the metal microreactor, and carrying out grid division; inputting physical information of the metal microreactor into the divided geometric model, mapping the physical information into a corresponding digital twin physical model, solving the model, and reasoning the distribution condition of a temperature field in the metal microreactor according to a solving result, so as to provide a mechanism for surface temperature measurement; by knowing the change mechanism of the internal temperature field, the position of the standard sensor placed on the surface of the micro-reactor is determined, and the indication error of the detected temperature sensor in the metal micro-reactor is calculated through a comparison method. According to the method, high-precision and standardized testing of the surface temperature of the microreactor can be realized, the service life of equipment is effectively prolonged, and the maintenance cost is reduced.

Description

Technical Field

[0001] The present invention relates to the field of metrology and calibration technology, and in particular to a metal microreactor surface temperature testing method based on digital twin technology. Background Art

[0002] As a highly efficient reaction equipment, metal microreactors are widely used in the chemical, pharmaceutical and energy fields. Its core advantage is that it achieves high mass and heat transfer efficiency through miniaturized structures, but the precise measurement of its surface temperature is relatively complex.

[0003] In the prior art, temperature sensors are usually embedded inside the interlayer of microreactors to achieve online monitoring. However, such sensors cannot be disassembled due to the compactness of the structure, resulting in the inability to calibrate or maintain them after long-term use. The measurement accuracy decreases significantly with the aging of the sensor, affecting the stability and safety of the reaction. During the operation of the microreactor, the surface temperature is always in a dynamic fluctuation state due to the rapid flow of the reaction substances and the exothermic / absorbent effects.

[0004] The traditional contact temperature measurement method does not understand the temperature change mechanism inside the microreactor, and uses standard sensors directly placed in the four corners and the center to test the temperature. This method has a large measurement error and cannot reflect the actual temperature condition of the microreactor. In addition, there is currently no unified metal microreactor surface temperature test standard in the industry. The test methods used in different research or production environments are different (such as random point temperature measurement, single-point static monitoring, etc.), resulting in poor data comparability and difficulty in supporting process optimization or horizontal evaluation of equipment performance. Summary of the invention

[0005] The purpose of the present invention is to provide a metal microreactor surface temperature testing method based on digital twin technology. A virtual and real digital twin physical model is constructed through digital twin technology to simulate the temperature changes of the microchannels inside the metal microreactor and the surrounding heat transfer oil, thereby characterizing the temperature distribution on the surface of the entire microreactor. It aims to break through the limitations of traditional technology and provide a standardized and intelligent solution for metal microreactor surface temperature testing.

[0006] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0007] A metal microreactor surface temperature testing method based on digital twin technology, the method comprising:

[0008] A temperature sensor is arranged on the feed port pipeline of the metal microreactor to monitor the temperature change of the feed port in real time and record the indication of the temperature sensor;

[0009] Establishing a geometric model according to the actual geometric size and internal structure of the metal microreactor, and meshing the geometric model;

[0010] The physical information of the metal microreactor is used as the boundary condition input into the divided geometric model, mapped into the corresponding digital twin physical model, and the model is solved. The temperature field distribution inside the metal microreactor is inferred based on the solution results, providing a mechanism for surface temperature measurement.

[0011] The placement position of the standard sensor is determined according to the simulation result of the internal temperature field distribution, and the indication error of the temperature sensor under test in the metal microreactor is calculated by a comparison method, so as to obtain the accurate value of the temperature sensor under test.

[0012] As a preferred solution of the present invention, the method of meshing the geometric model specifically includes:

[0013] Define the size of the mesh to be divided into , the entire geometric model is divided into A tiny model, the expression is:

[0014] ;

[0015] In the formula, Represents the geometry that needs to be divided;

[0016] Define the global variables of the partition, that is The geometry of a tiny model is expressed as:

[0017] ;

[0018] In the formula, To determine the size of the small shapes after division, triangle or quadrilateral division is used by default; tends to 0;

[0019] Create named selections of meshed edges, faces, and volumes, and update the named mesh.

[0020] As a preferred embodiment of the present invention, the physical information of the metal microreactor includes: feed reactant composition, density, thermal conductivity, feed port initial temperature, flow rate, microchannel material, thickness and heat flux, and heat transfer oil density and heat flux.

[0021] As a preferred embodiment of the present invention, the method for solving the model and reasoning about the temperature field distribution inside the metal microreactor specifically includes:

[0022] Define boundary conditions, iteration time and number of solution steps, using The turbulence model is used as a solution method to solve the digital twin physical model. The turbulence kinetic energy equation is expressed as:

[0023] ;

[0024] In the formula, is the fluid density; is the turbulent kinetic energy; Indicates a small change; is the velocity vector; is the spatial coordinate; is the turbulent viscosity coefficient; is the turbulent kinetic energy generated by the laminar velocity gradient, The turbulent kinetic energy generated by buoyancy; is the dissipation rate; Fluctuations due to diffusion;

[0025] The diffusion equation is expressed as:

[0026] ;

[0027] ;

[0028] In the formula, , , is a constant; is the dissipation rate suppression function; is a constant; , ;

[0029] According to the solution results, a temperature field change cloud diagram inside the metal microreactor is simulated, and the temperature is judged by different colors. The reasoning principle is:

[0030] ;

[0031] In the formula, Indicates the temperature change result after model inference; is the size of the tiny shapes after division; Indicates a small change; Both represent boundary conditions.

[0032] As a preferred solution of the present invention, the placement position of the standard sensor has the following requirements:

[0033] Avoid the cold spots in the corners around the metal microreactor;

[0034] Avoid high temperature spots between microchannels in metal microreactors;

[0035] The standard temperature sensors are arranged around the sensor under test.

[0036] As a preferred embodiment of the present invention, the method for calculating the indication error of the temperature sensor under test in the metal microreactor by the comparison method comprises:

[0037] The readings of the standard sensor and the sensor under test are collected once every preset time period and the average value is calculated. The formula is:

[0038] ;

[0039] ;

[0040] In the formula, is the average value of the standard sensor, Indicates Standard sensors, is the maximum number of standard sensors; is the number of measurements; is the maximum number of measurements, For standard sensors The measured value of is the average value of the temperature sensor under test; is the measured value of the temperature sensor under test;

[0041] Then the indication error of the temperature sensor under test is for: .

[0042] By real-time monitoring of the feed port temperature and combining it with the dynamic changes of the internal temperature field, the actual temperature distribution of the reactor under different operating conditions can be reflected, ensuring temperature monitoring in a highly dynamic reaction environment. The simulation calculation based on digital twin technology does not rely on traditional hardware sensors to directly measure the temperature, avoiding the problem of sensor aging or inability to disassemble, effectively extending the service life of the equipment and reducing maintenance costs. By establishing a digital twin physical model, the temperature field distribution inside the metal microreactor can be accurately simulated, and the surface temperature of the microreactor can be accurately calculated, overcoming the problem that the traditional contact measurement method cannot effectively capture the dynamic changes of the internal temperature, and ensuring the accuracy of the test data. The method of calibrating the indication error of the tested temperature sensor by a standard sensor can ensure the standardization and consistency of temperature measurement, which helps to promote the standardization of surface temperature testing of metal microreactors. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them: Figure 1 is a flow chart of the method of the present invention; Figure 2 This is a schematic diagram of the planar structure of a metal microreactor in an embodiment of the present invention; Figure 3 A schematic diagram of a geometric model established in an embodiment of the present invention; Figure 4 A schematic diagram of grid division in an embodiment of the present invention; Figure 5 This is a cloud diagram of temperature changes after stabilization in an embodiment of the present invention; Figure 6 This is a schematic diagram for comparing traditional surface temperature testing methods; Figure 7 Schematic diagram of the surface temperature testing method in an embodiment of the present invention. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0045] like Figure 1 As shown, it is an embodiment of the present invention, which provides a metal microreactor surface temperature testing method based on digital twin technology, which is used to solve the problems of non-detachable sensors in metal microreactors leading to difficulty in calibration, difficulty in capturing dynamic temperature changes in real time, and lack of standardized testing specifications.

[0046] The method comprises the following steps:

[0047] S1: A temperature sensor is arranged on the feed inlet pipe of the metal microreactor to monitor the temperature change of the feed inlet in real time and record the indication of the temperature sensor.

[0048] Due to the high requirements for temperature monitoring of metal microreactors, the temperature sensor of this embodiment preferably uses RTD (resistance temperature detector) or thermocouple. RTD has high accuracy and stability and is suitable for applications requiring high-precision measurement. Thermocouples perform better in high temperature ranges and are suitable for a wider temperature range. The specific choice can be determined according to the actual temperature range and accuracy requirements of the feed port.

[0049] In order to accurately capture the temperature changes at the feed inlet, the frequency of temperature data collection should be at least once per minute. If the system responds quickly or the reaction process is more dynamic, the sampling frequency can be increased to once per second to more accurately capture instantaneous temperature changes. The accuracy of the temperature sensor should be ±0.5°C or higher.

[0050] S2: Establish a geometric model based on the actual geometric dimensions and internal structure of the metal microreactor and perform mesh division.

[0051] The actual geometric features of the metal microreactor are converted into a digital three-dimensional model, and the geometric model is decomposed into tiny units through meshing to facilitate numerical simulation and calculation. After meshing, each small unit in the model can be calculated according to different physical conditions (such as temperature, flow rate, etc.), thereby obtaining an accurate temperature field distribution.

[0052] In one embodiment, the method of meshing a geometric model specifically includes:

[0053] Define the size of the mesh to be divided into , the entire geometric model is divided into A tiny model, the expression is:

[0054] ;

[0055] In the formula, Represents the geometry that needs to be divided;

[0056] Define the global variables of the partition, that is The geometry of a tiny model is expressed as:

[0057] ;

[0058] In the formula, To determine the size of the small shapes after division, triangle or quadrilateral division is used by default; tends to 0;

[0059] Create named selections of meshed edges, faces, and volumes, and update the named mesh.

[0060] S3: The physical information of the metal microreactor is input as the boundary condition into the divided geometric model, mapped into the corresponding digital twin physical model, and the model is solved. The internal temperature field distribution of the metal microreactor is inferred based on the solution results, providing a mechanism for surface temperature measurement.

[0061] The physical information of the metal microreactor includes: the composition, density, thermal conductivity of the feed reactants, the initial temperature of the feed port (obtained according to the temperature sensor indication in step S1), flow rate, microchannel material, thickness and heat flux, density and heat flux of the heat transfer oil, etc. The digital twin technology is used to construct a virtual-real digital twin physical model to simulate the temperature changes of the microchannel inside the metal microreactor and the surrounding heat transfer oil, thereby characterizing the temperature distribution on the entire microreactor surface.

[0062] In a specific embodiment, the method for solving the model and inferring the temperature field distribution inside the metal microreactor specifically includes:

[0063] Define boundary conditions, iteration time and number of solution steps, using The turbulence model is used as a solution method to solve the digital twin physical model. The turbulence kinetic energy equation is expressed as:

[0064] ;

[0065] In the formula, is the fluid density; is the turbulent kinetic energy; Indicates a small change; is the velocity vector; is the spatial coordinate; is the turbulent viscosity coefficient; is the turbulent kinetic energy generated by the laminar velocity gradient, The turbulent kinetic energy generated by buoyancy; is the dissipation rate; Fluctuations due to diffusion;

[0066] The diffusion equation is expressed as:

[0067] ;

[0068] ;

[0069] In the formula, , , is a constant; is the dissipation rate suppression function; is a constant; , ;

[0070] According to the solution results, a temperature field change cloud diagram inside the metal microreactor is simulated, and the temperature is judged by different colors. The reasoning principle is:

[0071] ;

[0072] In the formula, Indicates the temperature change result after model inference; is the size of the tiny shapes after division; Indicates a small change; Both represent boundary conditions.

[0073] The temperature field inside the metal microreactor is calculated through accurate numerical simulation, and the temperature distribution under different time and space conditions is inferred. The turbulence model is used to simulate the complex flow and heat transfer process of the fluid inside the microreactor, so as to more accurately predict the temperature field changes and provide real temperature data support.

[0074] S4: Determine the placement position of the standard sensor according to the simulation results of the internal temperature field distribution, calculate the indication error of the temperature sensor under test in the metal microreactor by comparison method, and thus obtain the accurate value of the temperature sensor under test.

[0075] Specifically, the placement of standard sensors has the following requirements:

[0076] Avoid the cold spots in the corners around the metal microreactor;

[0077] Avoid high temperature spots between microchannels in metal microreactors;

[0078] The standard temperature sensors are arranged around the sensor under test.

[0079] In one embodiment, the indication error of the temperature sensor under test in the metal microreactor is calculated by a comparison method, and the method includes:

[0080] The readings of the standard sensor and the sensor under test are collected once every preset time period and the average value is calculated. The formula is:

[0081] ;

[0082] ;

[0083] In the formula, is the average value of the standard sensor, Indicates Standard sensors, is the maximum number of standard sensors; is the number of measurements; is the maximum number of measurements, For standard sensors The measured value of is the average value of the temperature sensor under test; is the measured value of the temperature sensor under test;

[0084] Then the indication error of the temperature sensor under test is for: .

[0085] The error is calculated by comparing the indications of the standard sensor and the sensor under test, thereby realizing the calibration of the temperature sensor under test. In this way, the deviation of the sensor under test can be identified and its reading can be corrected, thereby ensuring the temperature measurement accuracy of the metal microreactor, improving the reliability and accuracy of the measurement, and ensuring the consistency of the test results with the actual situation.

[0086] Figure 2 A planar structural design of a metal microreactor in an embodiment of the present invention is demonstrated, which mainly includes elements such as microchannels, temperature sensors in the interlayer, thermal conductive silicone oil, etc., and can reflect the physical characteristics of the actual device.

[0087] A number of temperature sensors are installed in the microchannels of the metal microreactor. The temperature is transferred through the circulation of the heat transfer oil. The temperature sensors monitor the temperature of the oil flow through the channels in real time. A temperature sensor is installed at the inlet of the metal microreactor to monitor the temperature change in real time.

[0088] according to Figure 2 Plane structure establishment in Figure 3 The geometric model shown is mapped into the corresponding digital twin physical model to realize scene reproduction and perform meshing.

[0089] Define the global variable of the division as 0.5mm, that is , using the global triangle division method to achieve the mesh division of the entire model. Definition Figure 3 The feed inlet of the microchannel is defined as inlet, the outlet of the microchannel is defined as outlet, the heat transfer oil in the microreactor interlayer is oil-fluid, the boundary of the microreactor channel is re-wall, and the outermost edge of the heat transfer silicone oil is bian-wall. After updating the network, the results are as follows Figure 4 shown.

[0090] In order to study the thermal conductivity of the metal microreactor as a whole, this example simplifies the reaction materials and defines the component of the feed inlet as liquid pure water with a density of 1000 kg / m 3 , thermal conductivity is 0.6 The speed of the inlet is 1.2m / s, the temperature sensor at the inlet shows 50℃, the edge of the microchannel is defined as Hastelloy metal, and the heat flux is 50w / m 2 The thickness of the channel tube is 1mm. The microchannel and the entire microreactor are filled with thermal conductive silicone oil. The density, thermal conductivity and other information of the thermal conductive silicone oil are defined. The material of the outermost part of the metal microreactor is defined as Hass alloy with a thickness of 2mm. At the same time, the density, thermal conductivity and other information are defined.

[0091] The above related physical information is introduced into the formula to perform steady-state analysis on the model. The number of iterations is set to 200 steps and the step length is 1s. After the temperature is stable, the temperature field distribution of the entire metal microreactor is as follows: Figure 5 shown. Figure 5 This is a screenshot of the Fluent software (a commercial CFD software package), where Static Temperature is the static temperature and [C] represents the temperature unit.

[0092] Depend on Figure 5 It can be seen that after the temperature stabilizes, the temperature inside the entire microchannel is relatively high, and the overall temperature distribution of the metal microreactor is as follows:

[0093] (1) The temperature range between channels is (47.7~50.0)℃;

[0094] (2) The temperature at the inlet is higher, and the temperature at the outlet is slightly lower;

[0095] (3) The temperatures at the four corners of the metal microreactor are slightly different. The temperature at the inlet is between (45.4 and 48.7) °C, and the temperature at the outlet is relatively low, ranging from (36.1 to 38.4) °C.

[0096] Through Figure 5 By analyzing the surface temperature of the microreactor during the reaction, we can understand the temperature changes on the surface of the microreactor during the reaction, and at the same time, we can find that the temperature inside the metal microreactor is uneven.

[0097] like Figure 6 As shown in the figure, the four corners (A, B, C, D) and the center (O) of the metal microreactor are the cold and high points of the temperature. The traditional surface temperature testing method is prone to excessively high or low temperatures, and the temperature uniformity is poor, and it is impossible to truly understand the changes in the temperature inside the microreactor.

[0098] In the embodiment of the present invention, according to the simulated temperature change cloud map, w standard sensors are placed near the sensor to be tested and at a position where the temperature field is relatively concentrated, avoiding the temperature cold spots in the corners around the metal microreactor and the temperature high spots between the microchannels, such as Figure 7As shown. Data is collected every 2 minutes, and 10 sets of data are recorded. The error of the sensor under test is calculated by comparison. The average temperature of the four standard sensors is 44.3°C, and the average value displayed by the temperature sensor under test is 47.2°C. The indication error of the temperature sensor under test is 2.9°C. Other temperature sensors on the microreactor can be measured in the same way.

[0099] In summary, the present invention provides a high-precision and intelligent temperature measurement solution by establishing a digital twin physical model and combining it with the precise simulation and simulation of the internal and external temperature fields of the metal microreactor, which makes up for the shortcomings of traditional temperature measurement methods in dynamic reaction, temperature change and standardized testing.

[0100] By using digital twin technology, the present invention can fully and accurately simulate the heat conduction and fluid dynamic changes inside the metal microreactor, breaking through the problem that the traditional contact temperature measurement in the prior art cannot reflect temperature fluctuations and changes. By combining the temperature sensor and the virtual model, higher temperature monitoring accuracy and real-time feedback capabilities are ensured, effectively improving the working stability and safety of the metal microreactor.

[0101] By comparing and calibrating the indication of the temperature sensor under test with the standard sensor, the accuracy of temperature measurement can be ensured under different operating environments, solving long-standing problems such as sensor aging and position error, and providing a strong guarantee for the long-term operation of the metal microreactor equipment. Through simulation calculation and real-time feedback, the temperature change trend can be accurately reflected, and adjustments and optimizations can be made according to the temperature data at different locations, further improving the thermal efficiency and production efficiency of the metal microreactor.

[0102] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of various changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A metal microreactor surface temperature testing method based on digital twin technology, characterized in that: The method comprises: A temperature sensor is arranged on the feed port pipeline of the metal microreactor to monitor the temperature change of the feed port in real time and record the indication of the temperature sensor; Establishing a geometric model according to the actual geometric size and internal structure of the metal microreactor, and meshing the geometric model; The physical information of the metal microreactor is input as boundary conditions into the divided geometric model, mapped into the corresponding digital twin physical model, and the model is solved. The temperature field distribution inside the metal microreactor is inferred based on the solution results, providing a mechanism for surface temperature measurement. The placement position of the standard sensor is determined according to the simulation result of the internal temperature field distribution, and the indication error of the temperature sensor under test in the metal microreactor is calculated by a comparison method, so as to obtain the accurate value of the temperature sensor under test.

2. According to claim 1, a metal microreactor surface temperature testing method based on digital twin technology is characterized in that: The method for meshing the geometric model specifically includes: Define the size of the mesh to be divided into , the entire geometric model is divided into A tiny model, the expression is: ； In the formula, Indicates the geometry that needs to be divided; Define the global variables of the partition, that is The geometry of a tiny model is expressed as: ； In the formula, To determine the size of the small shapes after division, triangle or quadrilateral division is used by default; tends to 0; Create named selections of meshed edges, faces, and volumes, and update the named mesh.

3. According to claim 1, a metal microreactor surface temperature testing method based on digital twin technology is characterized in that: The physical information of the metal microreactor includes: feed reactant composition, density, thermal conductivity, feed inlet initial temperature, flow rate, microchannel material, thickness and heat flux, and heat transfer oil density and heat flux.

4. The metal microreactor surface temperature testing method based on digital twin technology according to claim 3 is characterized in that: The method for solving the model and inferring the temperature field distribution inside the metal microreactor specifically includes: Define boundary conditions, iteration time and number of solution steps, using The turbulence model is used as a solution method to solve the digital twin physical model. The turbulence kinetic energy equation is expressed as: ； In the formula, is the fluid density; is the turbulent kinetic energy; Indicates a small change; is the velocity vector; is the spatial coordinate; is the turbulent viscosity coefficient; is the turbulent kinetic energy generated by the laminar velocity gradient, The turbulent kinetic energy generated by buoyancy; is the dissipation rate; Fluctuations due to diffusion; The diffusion equation is expressed as: ； ； In the formula, , , is a constant; is the dissipation rate suppression function; is a constant; , ; According to the solution results, a temperature field change cloud diagram inside the metal microreactor is simulated, and the temperature is judged by different colors. The reasoning principle is: ； In the formula, Indicates the temperature change result after model inference; is the size of the tiny shapes after division; Indicates a small change; Both represent boundary conditions.

5. The metal microreactor surface temperature testing method based on digital twin technology according to claim 1, characterized in that: The placement of the standard sensor has the following requirements: Avoid the cold spots in the corners around the metal microreactor; Avoid high temperature spots between microchannels in metal microreactors; The standard temperature sensors are arranged around the sensor under test.

6. The metal microreactor surface temperature testing method based on digital twin technology according to claim 1 is characterized in that: The method of calculating the indication error of the temperature sensor under test in the metal microreactor by the comparison method comprises: The readings of the standard sensor and the sensor under test are collected once every preset time period and the average value is calculated. The formula is: ； ； In the formula, is the average value of the standard sensor, Indicates Standard sensors, is the maximum number of standard sensors; is the number of measurements; is the maximum number of measurements, For standard sensors The measured value of is the average value of the temperature sensor under test; is the measured value of the temperature sensor under test; Then the indication error of the temperature sensor under test is for: .

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