Method and system for correcting outlet wall temperature measured by a tube reactor thermocouple

Abstract

The application discloses a method and system for correcting outlet wall temperature measured by a tubular reactor thermocouple, and belongs to the technical field of thermocouple measurement, and solves the problem of low accuracy of existing thermocouple temperature measurement.The method comprises the following steps: measuring based on an experimental device, and the experimental device comprises a liquid storage tank, a pump, a copper electrode positive electrode, a pipeline, a power supply, a thermocouple measuring point, a copper electrode negative electrode, a condenser and a waste liquid tank.Because heat conduction will cause the output temperature of the thermocouple to be affected by the surrounding environment temperature and the cooling section, a measurement deviation is generated.The application corrects the outlet temperature of the thermocouple, and the influence can be eliminated.The results show that the average error between the corrected temperature experimental value and the actual value of the measuring point temperature is 8.89%, and the accuracy is improved by 20.05%.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of thermocouple measurement, and particularly to a temperature correction method for thermocouple measurement of a tubular reactor. BACKGROUND

[0002] Thermocouples are of great importance in the field of temperature measurement. They can provide accurate temperature measurements under various environmental conditions, including high temperatures, low temperatures, and extreme conditions. Thermocouples have fast response times and high durability, so they are widely used in industrial control systems, laboratory research, and other applications. The outlet temperature of a thermocouple may need to be corrected due to heat conduction, and this correction is important to ensure the accuracy of temperature measurement. Heat conduction can cause the output temperature of the thermocouple to be affected by the ambient temperature or the cooler connected at the outlet end, resulting in a deviation. SUMMARY

[0003] The present application aims to solve the problem of low accuracy of existing thermocouple temperature measurement, and provides a method and system for correcting the outlet wall temperature of a thermocouple measurement of a tubular reactor.

[0004] The present application is achieved by the following technical solutions. In one aspect, the present application provides a method for correcting the outlet wall temperature of a thermocouple measurement of a tubular reactor, which includes: setting up an experimental device, the experimental device including: a liquid storage tank, a pump, a copper electrode positive electrode, a pipe, a power supply, a thermocouple measurement point, a copper electrode negative electrode, a condenser, and a waste liquid tank;

[0005] The cooling medium is stored in the liquid storage tank, flows into the pipe through the pump, is heated, enters the condenser for cooling, and finally flows into the waste liquid tank;

[0006] The pipe is clamped by the copper electrode positive electrode and the copper electrode negative electrode;

[0007] The pipe is electrically heated by the power supply;

[0008] The thermocouple measurement point is located at the outlet position of the pipe;

[0009] The average temperature between the thermocouple measurement point and the condenser is obtained;

[0010] The heat flow of air convection heat transfer between the thermocouple measurement point and the condenser is obtained;

[0011] The heat flow of heat conduction between the thermocouple measurement point and the condenser is obtained;

[0012] The sum of the heat flow of air convection heat transfer and the heat flow of heat conduction between the thermocouple measurement point and the condenser is obtained according to the heat flow of air convection heat transfer and the heat flow of heat conduction between the thermocouple measurement point and the condenser;

[0013] The modified temperature is obtained according to the sum of the heat flow of the heat convection with air and the heat flow of the heat conduction.

[0014] Further, the calculation formula of the average temperature between the thermocouple measuring point and the condenser is:

[0015]

[0016] Wherein, T w1 is the outer wall temperature measured by the thermocouple at the thermocouple measuring point, in K; T w2 is the temperature on the left side of the condenser.

[0017] Further, the heat flow of the heat convection with air between the thermocouple measuring point and the condenser is obtained, specifically comprising:

[0018] According to the Newton cooling formula, the heat flow of the heat convection with air between the thermocouple measuring point and the condenser is:

[0019] Q1=h×A1×(T m -T a ) (2)

[0020] Wherein, Q1 is the heat flow of the heat convection with air between the thermocouple measuring point and the condenser, in W; A1 is the contact area with air under the corresponding length, in m 2 ; T a is the temperature of air, in K; h is the heat transfer coefficient of convection, in W / (m2·K).

[0021] Further, the heat flow of the heat conduction between the thermocouple measuring point and the condenser is obtained, specifically comprising: according to the Fourier law, the heat flow of the heat conduction between the thermocouple measuring point and the condenser is:

[0022]

[0023] Wherein, Q2 is the heat flow of the heat conduction between the thermocouple measuring point and the condenser, in W; A2 is the cross-sectional area of the pipeline, in m 2 ; ΔL is the distance between the thermocouple measuring point and the condenser, in m; λ is the thermal conductivity, in W / (m·K).

[0024] Further, the calculation formula of the sum of the heat flow of the heat convection with air and the heat flow of the heat conduction is:

[0025] Q=Q1+Q2 (4)

[0026] Wherein, Q is the sum of the heat flow of the heat convection with air and the heat flow of the heat conduction.

[0027] Further, the calculation formula of the modified temperature is:

[0028]

[0029] wherein T' w1 is the corrected temperature.

[0030] In a second aspect, the present application provides a system for correcting the outlet wall temperature measured by a thermocouple in a tubular reactor, comprising: an experimental device and a data processing device.

[0031] The experimental device comprises: a liquid storage tank, a pump, a copper electrode anode, a pipeline, a power supply, a thermocouple measuring point, a copper electrode cathode, a condenser and a waste liquid tank.

[0032] The liquid storage tank stores a cooling working medium, which flows into the pipeline through the pump, is heated, enters the condenser for cooling, and finally flows into the waste liquid tank.

[0033] The pipeline is clamped by the copper electrode anode and the copper electrode cathode.

[0034] The pipeline is electrically heated by the power supply.

[0035] The thermocouple measuring point is located at the outlet position of the pipeline.

[0036] The data processing device comprises: a total air convection heat and heat conduction heat flow acquisition module and a corrected temperature acquisition module.

[0037] The total air convection heat and heat conduction heat flow acquisition module is configured to: acquire an average temperature between the thermocouple measuring point and the condenser; acquire a heat flow of air convection heat between the thermocouple measuring point and the condenser; acquire a heat flow of heat conduction between the thermocouple measuring point and the condenser; and acquire a total air convection heat and heat conduction heat flow according to the heat flow of air convection heat between the thermocouple measuring point and the condenser and the heat flow of heat conduction between the thermocouple measuring point and the condenser.

[0038] The corrected temperature acquisition module is configured to acquire a corrected temperature according to the total air convection heat and heat conduction heat flow.

[0039] Further, the calculation formula of the average temperature between the thermocouple measuring point and the condenser is:

[0040]

[0041] wherein T w1 is the outer wall temperature measured by the thermocouple at the thermocouple measuring point, in units of K; T w2 is the temperature on the left side of the condenser.

[0042] The heat flow of air convection heat between the thermocouple measuring point and the condenser specifically comprises:

[0043] According to Newton cooling formula, the heat flow of heat convection between the thermocouple measuring point and the condenser to the air is:

[0044] Q1=h×A1×(T m -T a ) (2)

[0045] Wherein, Q1 is the heat flow of heat convection between the thermocouple measuring point and the condenser to the air, unit w;A1 is the contact area with the air under the corresponding length, unit m 2 ;T a is the temperature of the air, unit K;;h is the heat transfer coefficient, unit W / (m2·K);

[0046] The heat flow of heat conduction between the thermocouple measuring point and the condenser is obtained, and specifically includes: according to Fourier law, the heat flow of heat conduction between the thermocouple measuring point and the condenser is:

[0047]

[0048] Wherein, Q2 is the heat flow of heat conduction between the thermocouple measuring point and the condenser, unit w;A2 is the cross-sectional area of the pipeline, unit m 2 ;ΔL is the distance between the thermocouple measuring point and the condenser, unit m;λ is the thermal conductivity, unit W / (m·K).

[0049] Further, the calculation formula of the sum of the heat flow of heat convection and heat conduction with the air is:

[0050] Q=Q1+Q2 (4)

[0051] Wherein, Q is the sum of the heat flow of heat convection and heat conduction with the air.

[0052] Further, the calculation formula of the corrected temperature is:

[0053]

[0054] Wherein, T′ w1 is the corrected temperature.

[0055] The beneficial effects of the present application are:

[0056] Because heat conduction will cause the output temperature of the thermocouple to be affected by the surrounding environment temperature and the cooling section, thereby producing measurement deviation. The present application corrects the outlet temperature of the thermocouple, which can eliminate this influence. The results of the present application show that the average error between the experimental value of the corrected temperature and the actual value of the measuring point temperature is 8.89%, and the accuracy is improved by 20.05%.

[0057] The application can eliminate the influence by correcting the thermocouple outlet temperature, and ensure the accuracy of the measurement result. In industrial and scientific applications requiring high-precision temperature measurement, correcting heat conduction is crucial to ensure the accuracy of production process control and experimental research. BRIEF DESCRIPTION OF DRAWINGS

[0058] In order to more clearly illustrate the technical solutions of the present application, the drawings needed in the embodiments will be briefly introduced as follows. Obviously, for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0059] Figure 1 Figure of experimental device for the outlet wall temperature correction method of thermocouple measurement of tubular reactor of the present application;

[0060] Figure 2 Result comparison chart for the outlet wall temperature correction method of thermocouple measurement of tubular reactor of the present application;

[0061] In the figure, 1 is a liquid storage tank, 2 is a pump, 3 is a copper electrode positive electrode, 4 is a pipeline, 5 is a power supply, 6 is a thermocouple measurement point, 7 is a copper electrode negative electrode, 8 is a condenser, and 9 is a waste liquid tank. DETAILED DESCRIPTION

[0062] The embodiments of the present application will be described in detail below, and examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are intended to explain the present application, and cannot be understood as a limitation of the present application.

[0063] Embodiment one, an outlet wall temperature correction method of thermocouple measurement of tubular reactor, the method comprises: setting an experimental device, the experimental device comprises: a liquid storage tank, a pump, a copper electrode positive electrode, a pipeline, a power supply, a thermocouple measurement point, a copper electrode negative electrode, a condenser and a waste liquid tank;

[0064] The liquid storage tank stores a cooling working medium, which flows into the pipeline through the pump, is heated, enters the condenser for cooling, and finally flows into the waste liquid tank;

[0065] The pipeline is clamped by the copper electrode positive electrode and the copper electrode negative electrode;

[0066] The pipeline is electrically heated by the power supply;

[0067] The thermocouple measurement point is located at the outlet position of the pipeline;

[0068] It should be noted that, since the outlet wall temperature is corrected, there is only one thermocouple measurement point, which is specifically the nearest measurement point from the outlet of the pipeline 4.

[0069] acquiring an average temperature between the thermocouple measuring point and the condenser;

[0070] acquiring a heat flow of heat convection to air between the thermocouple measuring point and the condenser;

[0071] acquiring a heat flow of heat conduction between the thermocouple measuring point and the condenser;

[0072] acquiring a sum of the heat flow of heat convection to air and the heat flow of heat conduction between the thermocouple measuring point and the condenser according to the heat flow of heat convection to air and the heat flow of heat conduction between the thermocouple measuring point and the condenser;

[0073] acquiring a corrected temperature according to the sum of the heat flow of heat convection to air and the heat flow of heat conduction; it is to be noted that further necessary factors for acquiring the corrected temperature include a temperature on the left side of the condenser, an air temperature, a heat convection coefficient and an air contact area corresponding to a length.

[0074] In the embodiment, a correction method for measuring outlet wall surface temperature of a tubular reactor by a thermocouple is provided in view of technical defects and technical disadvantages in the prior art, and the correction method can ensure accuracy and reliability of the measured results of the outlet wall surface temperature and is closer to the true value.

[0075] Since the thermocouple measuring point is close to the condenser, there is an axial heat conduction problem along the pipeline direction between the thermocouple measuring point and the condenser, which causes errors in temperature measurement at the thermocouple measuring point, and the embodiment provides a correction method for the wall surface temperature at the thermocouple measuring point.

[0076] In the embodiment, the calculation formula of the average temperature between the thermocouple measuring point and the condenser is further limited, and specifically includes:

[0077] The calculation formula of the average temperature between the thermocouple measuring point and the condenser is:

[0078]

[0079] wherein, T w1 is the outer wall surface temperature measured by the thermocouple at the thermocouple measuring point, and the unit is K; T w2 is the temperature on the left side of the condenser.

[0080] Embodiment three, the embodiment is further limited to the pipe reactor thermocouple measurement outlet wall temperature correction method of embodiment two, in the embodiment, the heat flow of the air convection heat between the thermocouple measurement point and the condenser is further limited, and specifically includes:

[0081] The heat flow of the air convection heat between the thermocouple measurement point and the condenser is specifically included:

[0082] According to Newton cooling formula, the heat flow of the air convection heat between the thermocouple measurement point and the condenser is:

[0083] Q1=h×A1×(T m -T a ) (2)

[0084] Wherein, Q1 is the heat flow of the air convection heat between the thermocouple measurement point and the condenser, unit w;A1 is the contact area with air under corresponding length, unit m 2 ;T a is the temperature of air, unit K;H is the heat transfer coefficient, unit W / (m2·K).

[0085] Embodiment four, the embodiment is further limited to the pipe reactor thermocouple measurement outlet wall temperature correction method of embodiment three, in the embodiment, the heat flow of the heat conduction between the thermocouple measurement point and the condenser is further limited, and specifically includes:

[0086] The heat flow of the heat conduction between the thermocouple measurement point and the condenser is specifically included: according to Fourier law, the heat flow of the heat conduction between the thermocouple measurement point and the condenser is:

[0087]

[0088] Wherein, Q2 is the heat flow of the heat conduction between the thermocouple measurement point and the condenser, unit w;A2 is the cross-sectional area of the pipeline, unit m 2 ;ΔL is the distance between the thermocouple measurement point and the condenser, unit m;λ is the thermal conductivity, unit W / (m·K).

[0089] Embodiment five, the embodiment is further limited to the pipe reactor thermocouple measurement outlet wall temperature correction method of embodiment four, in the embodiment, the calculation formula of the sum of the heat flow of the air convection heat and the heat conduction is further limited, and specifically includes:

[0090] The calculation formula of the sum of the heat flow of the air convection heat and the heat conduction is:

[0091] Q=Q1+Q2 (4)

[0092] wherein Q is the sum of convective heat transfer with air and conductive heat flow.

[0093] Embodiment six, the embodiment is one kind of pipe reactor thermocouple measurement outlet wall temperature correction method of the further limitation of the first embodiment, in the embodiment, the calculation formula of the correction temperature is further limited, specifically includes:

[0094] The calculation formula of the correction temperature is:

[0095]

[0096] wherein T' w1 is the correction temperature.

[0097] In the embodiment, if there is no axial heat conduction between the thermocouple measuring point 6 and the condenser 8 along the direction of the pipeline 4, the correction temperature T' w1 satisfies the following formula:

[0098]

[0099] The value of the correction temperature T' w1 after the transformation of formula (5) is as follows:

[0100]

[0101] The method of the embodiment has the advantage of correcting the temperature error caused by axial heat conduction.

[0102] Embodiment seven, the embodiment is one kind of pipe reactor thermocouple measurement outlet wall temperature correction method of the embodiment of the above, specifically includes:

[0103] The embodiment of the application provides a kind of pipe reactor thermocouple measurement outlet wall temperature correction method, based on the order of equipment connection in experimental device diagram carries out thermocouple calibration.

[0104] As Figure 1 shown, the experimental device includes liquid storage tank 1, pump 2, copper electrode positive electrode 3, pipeline 4, power supply 5, thermocouple measuring point 6, copper electrode negative electrode 7, condenser 8 and waste liquid tank 9.

[0105] As shown in Figure l, the liquid storage tank 1 stores cooling working medium, which flows into the pipeline 4 through the pump 2, is heated and then cooled in the condenser 8, and finally flows into the waste liquid tank 9.

[0106] As Figure 1 shown, the pipeline 4 is clamped by the copper electrode positive electrode 3 and the copper electrode negative electrode 7.

[0107] As Figure 1 shown, the pipeline 4 is electrically heated by the power supply 5.

[0108] As Figure 1 shown, the thermocouple measuring point 6 is located at the outlet position of the pipeline 4.

[0109] Since the thermocouple measuring point 6 is close to the condenser 8, there is an axial heat conduction problem between the thermocouple measuring point 6 and the condenser 8 in the direction of the pipeline 4, which causes errors in temperature measurement at the thermocouple measuring point 6. Now a correction method for the wall temperature at the thermocouple measuring point 6 is given.

[0110] The average temperature between the thermocouple measuring point 6 and the condenser 8 provided by the embodiment is defined as:

[0111]

[0112] Wherein, T w1 is the outer wall temperature measured by the thermocouple at the thermocouple measuring point 6, unit K; T w2 is the temperature on the left side of the condenser.

[0113] According to Newton's cooling formula, the heat flow of heat convection between the thermocouple measuring point 6 and the condenser 8 to the air is:

[0114] Q1=h×A1×(T m -T a ) (2)

[0115] Wherein, Q1 is the heat flow of heat convection between the thermocouple measuring point 6 and the condenser 8 to the air, unit w; A1 is the contact area with the air under the corresponding length, unit m 2 ; T a is the temperature of the air, unit K; h is the heat transfer coefficient, unit w / (m2·K).

[0116] According to Fourier's law, the heat flow of heat conduction between the thermocouple measuring point 6 and the condenser 8 is:

[0117]

[0118] Wherein, Q2 is the heat flow of heat conduction between the thermocouple measuring point 6 and the condenser 8, unit w; A2 is the cross-sectional area of the pipeline, unit m 2 ; ΔL is the distance between the thermocouple measuring point 6 and the condenser 8, unit m; λ is the thermal conductivity, unit W / (m·K).

[0119] Define Q as the sum of the heat flow of heat convection and heat conduction:

[0120] Q=Q1+Q2 (4)

[0121] If there is no axial heat conduction along the direction of the pipe 4 between the thermocouple measuring point 6 and the condenser 8, the corrected temperature T' w1 The following formula is satisfied:

[0122]

[0123] The corrected temperature T' can be obtained by transforming equation (5) w1 The value of T' is shown in the following formula:

[0124]

[0125] Now the pipe length is increased, and when the same heat flux density is given, the position of the thermocouple measuring point 6 is far away from the position of the condenser 8. At this time, the error of the wall temperature caused by axial heat conduction can be ignored, and it can be approximately considered that the measured temperature of the thermocouple at the position of the thermocouple measuring point 6 is the wall temperature at the corresponding position of the thermocouple measuring point 6 under the original pipe length condition.

[0126] The verification results are shown in Table 1 and Table 2. Figure 2 The average error between the uncorrected temperature experimental value and the actual value of the measuring point temperature is 28.94%.

[0127] The verification results are shown in Table 1 and Table 2. Figure 2 The average error between the corrected temperature experimental value and the actual value of the measuring point temperature is 8.89%, and the accuracy is improved by 20.05%.

[0128] The pipe reactor thermocouple measuring outlet wall temperature correction method described in this embodiment can be applied to the correction of thermocouple wall outlet temperature in various application scenarios, and has a very wide application range. Therefore, this embodiment is not limited.

[0129] The pipe reactor thermocouple measuring outlet wall temperature correction method described in this embodiment can be applied to the correction of thermocouple wall outlet temperature in various application scenarios, and has a very wide application range. Therefore, this embodiment is not limited.

[0130] The pipe reactor thermocouple measuring outlet wall temperature correction method described in this embodiment, the metal pipe 4 is heated by direct current or alternating current heating.

[0131] The pipe reactor thermocouple measuring outlet wall temperature correction method described in this embodiment, the pipe reactor of the pipe 4 is not limited to a circular pipe, but can also be a square pipe or other shapes.

[0132] Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the features disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

[0133] It should be understood that the present disclosure is not limited to the precise structures as herein described and illustrated in the drawings, and that various modifications and changes can be made without departing from its scope. The scope of the present disclosure is limited only by the claims that follow.

Claims

1. A method for correcting the outlet wall temperature of a tubular reactor measured by thermocouples, characterized in that, The method includes: setting up an experimental setup, which includes: a liquid storage tank, a pump, a positive copper electrode, pipes, a power supply, thermocouple measuring points, a negative copper electrode, a condenser, and a waste liquid tank; The storage tank contains the cooling medium, which flows into the pipeline through a pump, is heated, enters the condenser for cooling, and finally flows into the waste liquid tank. The pipe is clamped by a positive copper electrode and a negative copper electrode; The pipes are electrically heated by a power source. The thermocouple measuring point is located at the outlet of the pipe; Obtain the average temperature between the thermocouple measuring point and the condenser; Obtain the heat flow rate of air convection between the thermocouple measuring point and the condenser; Obtain the heat flow rate of heat conduction between the thermocouple measuring point and the condenser; The sum of the heat flow from the thermocouple measuring point to the air via convection and the heat flow from the thermocouple measuring point to the condenser via thermal conduction is obtained. The corrected temperature is obtained based on the sum of the heat flow from air convection and heat conduction.

2. The method for correcting the outlet wall temperature of a tubular reactor using thermocouple measurement according to claim 1, characterized in that, The formula for calculating the average temperature between the thermocouple measuring point and the condenser is as follows: Wherein, T w1 is the outer wall surface temperature measured by the thermocouple at the thermocouple measurement point, in units of K; T w2 is the temperature on the left side of the condenser.

3. The method for correcting the outlet wall temperature of a tubular reactor measured by thermocouples according to claim 2, characterized in that, The acquisition of the heat flow rate of air convection between the thermocouple measuring point and the condenser specifically includes: According to Newton's law of cooling, the heat flow rate transferred from the thermocouple measuring point to the air via convection between the condenser and the air is: Q1 = h x Al x (T m - T a ) (2) Wherein, Q1 is the heat flow of the heat convection between the thermocouple measuring point and the condenser to the air, unit w; A1 is the contact area with the air under the corresponding length, unit m 2 ; T a is the temperature of the air, unit K; h is the heat transfer coefficient of convection, unit W / (m2·K).

4. The method for correcting the outlet wall temperature of a tubular reactor using thermocouple measurement according to claim 3, characterized in that, The acquisition of the heat flow rate between the thermocouple measuring point and the condenser specifically includes: According to Fourier's law, the heat flow rate between the thermocouple measuring point and the condenser is: Wherein, Q2 is the heat flow of heat conduction between the thermocouple measuring point and the condenser, unit w; A2 is the cross-sectional area of the pipeline, unit m 2 ; ΔL is the distance between the thermocouple measuring point and the condenser, unit m; λ is the thermal conductivity, unit W / (m·K).

5. The method for correcting the outlet wall temperature of a tubular reactor using thermocouple measurement according to claim 4, characterized in that, The formula for calculating the sum of heat flow from air convection and heat conduction is as follows: Q = Q1 + Q2 (4) Where Q is the sum of heat flow from convection and conduction with air.

6. The method for correcting the outlet wall temperature of a tubular reactor using thermocouple measurement according to claim 5, characterized in that, The formula for calculating the corrected temperature is: where T' is the corrected temperature. w1 is the corrected temperature.

7. A correction system for thermocouple measurement of outlet wall temperature in a tubular reactor, characterized in that, The system includes: an experimental setup and a data processing setup; The experimental setup includes: a storage tank, a pump, a positive copper electrode, pipes, a power supply, thermocouple measuring points, a negative copper electrode, a condenser, and a waste liquid tank. The storage tank contains the cooling medium, which flows into the pipeline through a pump, is heated, enters the condenser for cooling, and finally flows into the waste liquid tank. The pipe is clamped by a positive copper electrode and a negative copper electrode; The pipes are electrically heated by a power source. The thermocouple measuring point is located at the outlet of the pipe; The data processing device includes: a module for acquiring the sum of heat flow from air convection and heat conduction, and a module for acquiring corrected temperature. The module for obtaining the sum of heat transfer and heat conduction between the thermocouple and the condenser is used to obtain the average temperature between the thermocouple measuring point and the condenser; obtain the heat flow rate of heat transfer from the thermocouple measuring point and the condenser to the air via convection; obtain the heat flow rate of heat conduction between the thermocouple measuring point and the condenser; and obtain the sum of heat transfer and heat conduction between the thermocouple measuring point and the condenser based on the heat flow rate of heat transfer from the thermocouple measuring point and the condenser to the air via convection and the heat flow rate of heat conduction between the thermocouple measuring point and the condenser. The corrected temperature acquisition module is used to acquire the corrected temperature based on the sum of the heat transfer flow with air via convection and heat conduction.

8. The thermocouple measurement outlet wall temperature correction system for a tubular reactor according to claim 7, characterized in that, The formula for calculating the average temperature between the thermocouple measuring point and the condenser is as follows: Wherein, T w1 is the outer wall surface temperature measured by the thermocouple at the thermocouple measurement point, in units of K; T w2 is the temperature on the left side of the condenser; The acquisition of the heat flow rate of air convection between the thermocouple measuring point and the condenser specifically includes: According to Newton's law of cooling, the heat flow rate transferred from the thermocouple measuring point to the air via convection between the condenser and the air is: Q1 = h x Al x (T m - T a ) (2) Wherein, Q1 is the heat flow of the heat convection between the thermocouple measuring point and the condenser to the air, unit w; A1 is the contact area with the air under the corresponding length, unit m 2 ; T a is the temperature of the air, unit K; h is the heat transfer coefficient of convection, unit W / (m2·K); The acquisition of the heat flow rate between the thermocouple measuring point and the condenser specifically includes: According to Fourier's law, the heat flow rate between the thermocouple measuring point and the condenser is: Wherein, Q2 is the heat flow of heat conduction between the thermocouple measuring point and the condenser, unit w; A2 is the cross-sectional area of the pipeline, unit m 2 ; ΔL is the distance between the thermocouple measuring point and the condenser, unit m; λ is the thermal conductivity, unit W / (m·K).

9. A thermocouple-based outlet wall temperature correction system for a tubular reactor according to claim 8, characterized in that, The formula for calculating the sum of heat flow from air convection and heat conduction is as follows: Q = Q1 + Q2 (4) Where Q is the sum of heat flow from convection and conduction with air.

10. A thermocouple-based outlet wall temperature correction system for a tubular reactor according to claim 9, characterized in that, The formula for calculating the corrected temperature is: Among them, T' w1 It's a temperature correction.

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