Temperature measurement correction method for high-temperature solid walls

Abstract

The application provides a high-temperature solid wall temperature measurement correction method, and the wall temperature measurement result will have a larger error under the high-speed high-temperature high-pressure fluid scouring. The application firstly establishes the convection heat transfer equation of the temperature sensor and the fluid on one side of the measured wall, the radiation heat transfer equation with the surrounding environment, and the heat conduction equation between the lead wire and the temperature sensor, then calculates the interference heat flux density according to the heat balance equation, establishes the cylindrical coordinate system with the sensor and the center of the measured wall as the origin, establishes the heat conduction differential equation of the measured solid wall, deduces the correction temperature formula of the measured high-temperature solid wall, and substitutes the interference heat flux density and the temperature sensor indication into the correction temperature formula to obtain the correction temperature of the measured high-temperature solid wall. The application only needs to consider the structure parameters of the measured wall and the running parameters of the fluid, and does not need to consider the structure parameters of the flow passage on the other side and the running parameters of the fluid, so that the accurate actual measurement value can be calculated, and the practicability, applicability and accuracy of the measurement are improved.

Description

Technical Field

[0001] This invention belongs to the field of contact sensor temperature measurement technology, specifically relating to a method for temperature measurement correction of a high-temperature solid wall surface. Background Technology

[0002] In industrial production and scientific research, it is often necessary to measure the temperature inside or on the surface of solids to test certain parameters and ensure product quality. Solid temperature is one of the most important process parameters in aerospace, energy, chemical, and metallurgical production processes. Accurate temperature measurement and control play a crucial role in industrial production, ensuring high-quality, high-yield, low-consumption, and safe production processes. In practice, many temperature measurements require fluid flow on both sides of the solid wall, such as in aircraft engine turbines, internal combustion engine cylinders, and heat exchangers. However, solid temperature measurement technology is still imperfect, especially the accurate measurement of solid wall temperature, which is affected by various factors such as internal heat transfer and boundary heat transfer conditions. Internal heat transfer in a solid depends on the material's thermal properties, such as thermal conductivity, density, and specific heat capacity. Boundary heat transfer conditions depend on the convective heat transfer coefficient between the measured wall and the fluid. Therefore, accurately measuring solid wall temperatures is quite difficult.

[0003] When measuring the temperature of a liquid, a relatively accurate temperature can be obtained as long as the temperature sensor has sufficient insertion depth and convective heat transfer conditions. However, for measuring the temperature of a solid wall, the sensor generally cannot be inserted into the solid surface, or cannot be inserted very deeply. Especially in the temperature measurement of solids with non-uniform temperature fields, even when using an embedded temperature sensor, the sensor's temperature reading will differ from the actual temperature of the measured wall. Therefore, it is necessary to study correction devices and methods for contact-type wall temperature measurement.

[0004] Taking thermocouples as an example, when using a sheathed thermocouple for temperature measurement, although the sensing part of the thermocouple is in contact with the surface being measured, the sensing point of the thermocouple is not actually in contact with the surface. Furthermore, when the sensing part of the thermocouple comes into contact with a solid surface, it disrupts the original temperature field. This interferes with the original heat flux density of the surface being measured, which is one of the reasons for errors in contact temperature sensors. Consequently, the temperature displayed by the sensor cannot accurately represent the actual temperature of the surface being measured, reducing the sensor's measurement accuracy. Summary of the Invention

[0005] Under special conditions such as high temperature, high pressure, and high-speed fluid, the contact between the sensing point of the sensor and the measured wall surface causes a concentration of heat flux density on the wall, resulting in a large temperature measurement error on high-temperature solid walls (hereinafter referred to as solid walls). Therefore, the temperature sensor reading only represents the temperature of the sensor's sensing part, not the actual temperature value of the measured wall surface. Therefore, the technical problem to be solved by this invention is to address the inaccurate solid wall surface temperature measurement problem in the prior art by theoretically deriving a correction formula for wall surface temperature measurement error to correct the sensor reading.

[0006] To address the above problems, this invention provides a method for correcting the temperature measurement of a high-temperature solid wall surface, comprising:

[0007] Step 1: Collect the temperature T0, pressure p0, and mass flow rate q of the incoming fluid from one side of the high-temperature solid wall being tested. m Calculate the static temperature T of the incoming flow. f1 Static pressure p f1 And flow velocity V:

[0008]

[0009]

[0010]

[0011]

[0012]

[0013] In the formula, γ represents the adiabatic index of the fluid, and c cr R represents the speed of sound, R represents the universal gas constant, and A represents the speed of sound. s q represents the fluid flow area at point A of a contact temperature sensor measuring the surface of a high-temperature solid wall. m R represents the mass flow rate of the fluid. g q represents the gas constant. v Indicates the volumetric flow rate of the fluid;

[0014] Step 2: When using contact temperature sensor A to measure a high-temperature solid wall, calculate the heat flux density q transferred by the sensing part of sensor A to the measured high-temperature solid wall via thermal conduction during sensor installation. T Specifically, it is described as follows:

[0015] Step 2.1: Calculate the convective heat transfer Φ between the sensing element of the contact temperature sensor A, which measures the high-temperature solid wall, and the surrounding fluid, based on Newton's law of cooling. h :

[0016] Φ h =h1A s1(T f1 -T s )

[0017]

[0018]

[0019]

[0020] q m =ρVA1

[0021] In the formula, h1 represents the convective heat transfer coefficient between the sensing part of the contact temperature sensor A and the fluid on one side of the measured wall, A s1 T represents the area of ​​contact between the contact temperature sensor A and the surrounding fluid. s This represents the reading of contact temperature sensor A, where Nu1 represents the Nusselt number between the sensing element of contact temperature sensor A and the fluid on one side of the measured high-temperature solid wall, and d. s The characteristic length of the sensing part of the contact temperature sensor A is represented by μ, the kinematic viscosity of the fluid is represented by ρ, the density of the fluid at its current state is represented by Pr1, the Prandtl number of the fluid is represented by Re1, and the flow Reynolds number of the fluid is represented by c. p λ represents the specific heat capacity at constant pressure of the fluid, V represents the velocity of the fluid in the flow channel, and λ represents the thermal conductivity of the fluid.

[0022] Step 2.2: Calculate the radiative heat transfer Φ between the sensing part of the contact temperature sensor A and the surrounding environment. r :

[0023]

[0024] In the formula, ε1 represents the emissivity of the sensing part of the contact temperature sensor A, σ represents the blackbody radiation constant, and T r Indicates the radiant temperature of the surrounding environment;

[0025] Step 2.3: Calculate the heat conduction Φ between the sensing part and the wire of the contact temperature sensor A. λ :

[0026]

[0027]

[0028] In the formula, h t d represents the composite surface heat transfer coefficient between the outer surface of the optical fiber lead, the fluid, and the environment. y λ represents the diameter of the leads of a contact temperature sensor. y T represents the thermal conductivity of the lead material of contact temperature sensor A. ∞H represents the temperature at the distal end of the lead of contact temperature sensor A, tanh() represents the hyperbolic tangent function, and H y Nu represents the length of the fiber optic lead. y h represents the Nusselt number between the lead of contact temperature sensor A and the fluid on one side of the high-temperature solid wall being measured. y d represents the convective heat transfer coefficient between the lead of contact temperature sensor A and the fluid on one side of the measured high-temperature solid wall. y Where is the diameter of the lead wire of temperature sensor A;

[0029] Step 2.4: Calculate the heat flux density q transferred by the sensing part of the contact temperature sensor A to the measured high-temperature solid wall surface via thermal conduction during installation. T :

[0030]

[0031] In the formula, A s2 This represents the contact area between the sensing part of temperature sensor A and the wall surface of the high-temperature solid being measured.

[0032] Step 3: Calculate the heat flux density q transferred by the fluid to the high-temperature solid wall via convection when no temperature sensor is installed. b :

[0033] q b =h b (T f1 -T w )

[0034] In the formula, h b T represents the convective heat transfer coefficient between the measured high-temperature solid wall and the fluid before the temperature sensor is installed. w This indicates the temperature of the fluid on the other side of the wall of the high-temperature solid being measured;

[0035] The convective heat transfer coefficient h between the measured high-temperature solid wall and the fluid b Represented as:

[0036]

[0037] f = (1.82lgRe) b -1.64) -2 ,

[0038] In the formula, l1 represents the length of the fluid channel, A1 represents the flow cross-sectional area of ​​the channel, P1 represents the length of the contact surface between the fluid channel wall and the fluid, and c t Indicates thermal property parameters;

[0039] Step 4: Calculate the interference heat flux density q when installing the sensor. d:

[0040] q d =q T -q b

[0041] Step 5: Establish a cylindrical coordinate system with the center of the sensor in the high-temperature solid being measured as the origin, and establish the thermal conductivity differential equation:

[0042]

[0043] In the formula, t represents the deviation temperature inside the measured high-temperature solid, r represents the distance to the vertical axis, and z represents the distance from the vertical direction of the wall of the measured high-temperature solid to the origin of the coordinate system.

[0044] Step 6: Calculate the absolute error Δt when measuring a high-temperature solid wall surface:

[0045]

[0046] In the formula, r e λ represents the effective diameter between temperature sensor A and the wall surface of the high-temperature solid being measured. w This represents the thermal conductivity of the wall surface of the high-temperature solid being measured.

[0047] Step 7: Calculate the actual measured temperature T of the high-temperature solid wall surface being tested. z :

[0048] T z =T s ±△t

[0049] When the temperature of the measured high-temperature solid wall is lower than the fluid temperature, a "+" sign is used; when the temperature of the measured high-temperature solid wall is higher than the fluid temperature, a "-" sign is used.

[0050] The beneficial effects of this invention are:

[0051] Under special conditions such as high temperature, high pressure, and high-speed fluid, the temperature measurement error of a high-temperature solid wall (hereinafter referred to as solid wall) can be large. Therefore, in engineering applications requiring accurate temperature acquisition, it is necessary to theoretically correct the temperature sensor readings to characterize the actual measured temperature. By considering the convective heat transfer error and radiation error between temperature sensor A and the surrounding environment, as well as the thermal conductivity error between the sensor and the wires and the high-temperature measured wall, an interference heat flux density is established. The deviation temperature distribution within the high-temperature measured wall is theoretically derived, and the reading of sensor A is theoretically corrected. This invention only needs to consider the structural parameters of the measured wall and the fluid operating parameters, without considering the structural parameters and fluid operating parameters of the flow channel on the other side, to calculate the accurate actual measurement value, thus improving the practicality, applicability, and accuracy of the measurement. Attached Figure Description

[0052] Figure 1 This is a flowchart of the temperature measurement and correction method for high-temperature solid walls in this invention;

[0053] Figure 2 This is a diagram illustrating the heat transfer relationship of the temperature sensor in this invention.

[0054] Figure 3 This is an installation diagram of the solid-wall sensor under test in this invention;

[0055] Figure 4 This is a schematic diagram of the installation of the temperature measurement sensor in the combustion chamber of an aero-engine in this invention. Detailed Implementation

[0056] The invention will be further explained below with reference to the accompanying drawings and specific implementation examples.

[0057] Traditional thermocouple temperature measurement methods involve welding the thermocouple to the surface of the object being measured. When using a traditional thermocouple to measure the high-temperature wall temperature of an aero-engine, the sensing element of the thermocouple undergoes convective heat transfer with the surrounding high-speed flowing fluid, radiative heat transfer with the surrounding radiating surfaces, and conduction heat with the leads. Therefore, the process of measuring the high-temperature wall temperature of an aero-engine is accompanied by convection errors, conduction errors, and radiation errors. This results in the temperature displayed by a traditional thermocouple not accurately representing the actual temperature of the measured wall, thus reducing the accuracy of thermocouple temperature measurement.

[0058] Another method of thermocouple temperature measurement involves creating grooves on the surface of the hot junction component and embedding the thermocouple using an embedded method, then adding material to fill and bond it to the hot junction component. However, embedded thermocouples can damage the surface structure being measured and are difficult to apply to the temperature measurement of thin-walled surfaces.

[0059] Temperature measurement using temperature-indicating paint is greatly affected by test conditions and requires image recognition and interpretation, which complicates the measurement process, resulting in lower test accuracy and the inability to interpret temperatures at non-isothermal points.

[0060] like Figure 1 As shown, this invention provides a method for temperature measurement correction of a high-temperature solid wall surface. The installation diagram of the solid wall sensor is shown below. Figure 3 As shown, it includes the following steps:

[0061] Step 1: Temperature sensor, pressure sensor, and orifice plate flow meter respectively collect the temperature T0, pressure p0, and mass flow rate q of the incoming fluid from one side of the high-temperature solid wall being measured. m The sensor installation location is as follows: Figure 4 As shown, the temperature of the combustion chamber wall of an aero-engine is measured using an armored thermocouple. The temperature reading of the armored thermocouple is read, and the static temperature T of the incoming flow is calculated. f1 Static pressure p f1 And flow velocity V:

[0062]

[0063]

[0064]

[0065]

[0066]

[0067] In the formula, γ represents the adiabatic index of the fluid (typically taken as 1.33 for the gas used in aircraft engines), and c cr R represents the speed of sound, R represents the universal gas constant (the gas used in aircraft engines, typically taken as 287.41 J / (kg·K)), and A represents the speed of sound. s q represents the fluid flow area at point A of a contact temperature sensor measuring the surface of a high-temperature solid wall. m R represents the mass flow rate of the fluid. g q represents the gas constant. v Indicates the volumetric flow rate of the fluid;

[0068] Step 2: When using contact temperature sensor A to measure a high-temperature solid wall, calculate the heat flux density q transferred by the sensing part of sensor A to the measured high-temperature solid wall via thermal conduction during sensor installation. T Specifically, it is described as follows:

[0069] Step 2.1: Read the reading T of temperature sensor A s The convective heat transfer Φ between the sensing part of the contact temperature sensor A (i.e., the armored thermocouple) measuring the high-temperature solid wall surface and the surrounding fluid is calculated based on Newton's law of cooling. h :

[0070] Φ h =h1A s1 (T f1 -T s )

[0071]

[0072]

[0073]

[0074] q m =ρVA1

[0075] In the formula, h1 represents the convective heat transfer coefficient between the sensing part of the contact temperature sensor A and the fluid on one side of the measured wall, A s1T represents the area of ​​contact between the contact temperature sensor A and the surrounding fluid. s This represents the reading of contact temperature sensor A, where Nu1 represents the Nusselt number between the sensing element of contact temperature sensor A and the fluid on one side of the measured high-temperature solid wall, and d. s The characteristic length of the sensing part of the contact temperature sensor A is represented by μ, the kinematic viscosity of the fluid is represented by ρ, the density of the fluid at its current state is represented by Pr1, the Prandtl number of the fluid is represented by Re1, and the flow Reynolds number of the fluid is represented by c. p λ represents the specific heat capacity at constant pressure of the fluid, V represents the velocity of the fluid in the flow channel, and λ represents the thermal conductivity of the fluid.

[0076] Step 2.2: Calculate the radiative heat transfer Φ between the sensing part of the contact temperature sensor A and the surrounding environment. r :

[0077]

[0078] In the formula, ε1 represents the emissivity of the sensing part of the contact temperature sensor A, σ represents the blackbody radiation constant, and T r Indicates the radiant temperature of the surrounding environment;

[0079] Step 2.3: Calculate the heat conduction Φ between the sensing part and the wire of the contact temperature sensor A. λ :

[0080]

[0081] (The leads of the armored thermocouple are perpendicular to the fluid direction on the side of the wall being measured.)

[0082] In the formula, h t d represents the composite surface heat transfer coefficient between the outer surface of the optical fiber lead, the fluid, and the environment. y λ represents the diameter of the leads of a contact temperature sensor. y T represents the thermal conductivity of the lead material of contact temperature sensor A. ∞ H represents the temperature at the distal end of the lead of contact temperature sensor A, tanh() represents the hyperbolic tangent function, and H y Nu represents the length of the fiber optic lead. y h represents the Nusselt number between the lead of contact temperature sensor A and the fluid on one side of the high-temperature solid wall being measured. y d represents the convective heat transfer coefficient between the lead of contact temperature sensor A and the fluid on one side of the measured high-temperature solid wall. y Where is the diameter of the lead wire of temperature sensor A;

[0083] Step 2.4: Calculate the heat conduction method (e.g., for the sensing part of contact temperature sensor A during installation) Figure 2The heat flux density q transferred to the surface of the high-temperature solid being measured T :

[0084]

[0085] In the formula, A s2 This represents the contact area between the sensing part of temperature sensor A and the wall surface of the high-temperature solid being measured.

[0086] Step 3: Calculate the heat flux q transferred from the fluid to the high-temperature solid wall being measured via convection when no armored thermocouple is installed. b :

[0087] q b =h b (T f1 -T w )

[0088] In the formula, h b T represents the convective heat transfer coefficient between the measured high-temperature solid wall and the fluid before the temperature sensor is installed. w This indicates the temperature of the fluid on the other side of the high-temperature solid wall being measured in the combustion chamber of an aero-engine (the specific value depends on the experimental conditions).

[0089] The convective heat transfer coefficient h between the measured high-temperature solid wall and the fluid b (Obtained from the precise experimental correlation of the calculated forced convection heat transfer within the tube-sink—the Gnilinsky experimental correlation) is expressed as:

[0090]

[0091] f = (1.82lgRe) b -1.64) -2 ,

[0092] In the formula, l1 represents the length of the fluid channel, A1 represents the flow cross-sectional area of ​​the channel, P1 represents the length of the contact surface between the fluid channel wall and the fluid, and c t Reflects the influence of thermophysical parameters;

[0093] Step 4: Calculate the interference heat flux density q when installing the sensor. d :

[0094] q d =q T -q b

[0095] Step 5: Establish a cylindrical coordinate system with the center of the sensor in the high-temperature solid being measured as the origin, and establish the thermal conductivity differential equation:

[0096]

[0097] In the formula, t represents the deviation temperature inside the measured high-temperature solid, r represents the distance to the vertical axis, and z represents the distance from the vertical direction of the wall of the measured high-temperature solid to the origin of the coordinate system.

[0098] Step 6: Calculate the absolute error Δt when measuring the high-temperature solid wall surface, and include the interfering heat flux density q. d The reading T of the contact temperature sensor A s Substituting the absolute error Δt into the equation, the trimming temperature of the solid wall can be calculated. The sensor reading is then corrected to obtain the actual temperature of the solid wall being measured.

[0099]

[0100] In the formula, r e λ represents the effective diameter between temperature sensor A and the wall surface of the high-temperature solid being measured. w This represents the thermal conductivity of the wall surface of the high-temperature solid being measured.

[0101] Step 7: Calculate the actual measured temperature T of the high-temperature solid wall surface being tested. z :

[0102] T z =T s ±△t

[0103] When the temperature of the measured high-temperature solid wall is lower than the fluid temperature, a "+" sign is used; when the temperature of the measured high-temperature solid wall is higher than the fluid temperature, a "-" sign is used.

[0104] This invention first measures the total temperature, total pressure, and mass flow rate of a high-speed incoming flow using a temperature sensor, a total pressure sensor, and an orifice plate flow meter, respectively, to calculate the static temperature, static pressure, and flow velocity of the incoming flow. Then, considering the actual conditions of heat conduction between the sensing element of the sheathed thermocouple and the combustion chamber of the aero-engine, convective heat transfer between the sensing element and the fluid on one side of the combustion chamber, radiative heat transfer between the sensing element and the surrounding environment, and heat conduction between the sensing element and its leads, it establishes equations for convective heat transfer between the sensing element of the sheathed thermocouple and the fluid on one side of the combustion chamber, radiative heat transfer between the sensing element and the surrounding environment, and heat conduction between the sensing element and its leads. Based on these equations, it calculates the heat flux density in the combustion chamber when the sheathed thermocouple is installed, and calculates the heat flux density in the combustion chamber without the sensor installed, obtaining the interference heat flux density. Finally, it obtains the corrected temperature inside the combustion chamber of the aero-engine.

[0105] The contact thermal resistance and diffusion thermal resistance between the armored thermocouple and the measured wall surface are difficult to calculate directly and accurately. Therefore, this invention only considers the structural parameters of the flow channel and the fluid operating parameters on one side of the measured wall surface, without considering the structural parameters of the flow channel and the fluid operating parameters on the other side. Based on this, the corrected temperature of the measured wall surface is derived theoretically. The interference heat flux density generated by the installation and non-installation of the armored thermocouple is substituted into the corrected temperature. The true temperature is obtained by adding the corrected temperature to the armored thermocouple reading.

Claims

1. A method for correcting the temperature measurement of a high-temperature solid wall surface, characterized in that, include: Step 1: Collect the temperature of the incoming fluid on one side of the high-temperature solid wall being tested. ,pressure mass flow rate The static temperature of the flow state was calculated. static pressure and flow rate ; Step 2: When using contact temperature sensor A to measure a high-temperature solid wall, calculate the heat flux density transferred from the sensing part of contact temperature sensor A to the measured high-temperature solid wall via thermal conduction during sensor installation. Specifically, this is achieved through the following formula: ； in, This represents the contact area between the sensing element of temperature sensor A and the surface of the high-temperature solid being measured. The heat transfer between the sensing element of contact temperature sensor A and the surrounding fluid is due to convection. This refers to the radiative heat transfer between the sensing element of contact temperature sensor A and the surrounding environment. The heat conduction between the sensing part of the contact temperature sensor A and the wire; Step 3: Calculate the heat flux density transferred by the fluid to the high-temperature solid wall being measured via convection when no temperature sensor is installed. Specifically, this is achieved through the following formula: ； in, This represents the convective heat transfer coefficient between the measured high-temperature solid wall and the fluid before the temperature sensor was installed. This indicates the temperature of the fluid on the other side of the wall of the high-temperature solid being measured; Step 4: Calculate the interference heat flux density when installing the sensor Specifically, this is achieved through the following formula: ； Step 5: Establish a cylindrical coordinate system with the center of the sensor in the high-temperature solid being measured as the origin, and establish the thermal conductivity differential equation; Step 6: Calculate the absolute error when measuring a high-temperature solid wall surface Specifically, it is calculated using the following formula: ， In the formula, This represents the effective diameter between temperature sensor A and the wall surface of the high-temperature solid being measured. This represents the thermal conductivity of the wall surface of the high-temperature solid being measured. This represents the contact area between the sensing part of temperature sensor A and the wall surface of the high-temperature solid being measured. Step 7: Calculate the actual temperature measurement value of the high-temperature solid wall surface being tested. Specifically, this is achieved through the following formula: in, The reading of contact temperature sensor A is indicated by "+" when the temperature of the measured high-temperature solid wall is lower than the fluid temperature, and "-" when the temperature of the measured high-temperature solid wall is higher than the fluid temperature.

2. The method for temperature measurement correction of a high-temperature solid wall surface according to claim 1, characterized in that, The static temperature of the incoming flow in step 1 static pressure and flow rate Represented as: In the formula, The adiabatic index indicates the thermal properties of a fluid. Indicates the speed of sound. Represents the universal gas constant. This represents the fluid flow area at point A of a contact temperature sensor used to measure the surface of a high-temperature solid wall. Indicates the mass flow rate of the fluid. Represents the gas constant. This indicates the volumetric flow rate of the fluid.

3. The method for temperature measurement correction of a high-temperature solid wall surface according to claim 1, characterized in that, The convective heat transfer between the sensing element of the contact temperature sensor A in step 2 and the surrounding fluid. The radiative heat transfer between the sensing element of contact temperature sensor A and the surrounding environment. The heat conduction between the sensing part and the wire of the contact temperature sensor A Calculated in the following way: The convective heat transfer between the sensing element of a contact temperature sensor A, which measures the temperature of a high-temperature solid wall, and the surrounding fluid is calculated based on Newton's law of cooling. : In the formula, This represents the convective heat transfer coefficient between the sensing element of contact temperature sensor A and the fluid on one side of the measured wall. This represents the area of ​​contact between the contact temperature sensor A and the surrounding fluid. This indicates the reading of contact temperature sensor A. This represents the characteristic length of the sensing part of the contact temperature sensor A. Indicates the kinematic viscosity of a fluid. Density represents the state of a fluid. The Prandtl number represents the fluid. The Reynolds number represents the flow rate of a fluid. This represents the specific heat capacity at constant pressure of a fluid. Indicates the thermal conductivity of a fluid; Calculate the radiative heat transfer between the sensing element of contact temperature sensor A and the surrounding environment. : In the formula, This represents the emissivity of the sensing element of contact temperature sensor A. This represents the blackbody radiation constant. Indicates the radiant temperature of the surrounding environment; Calculate the heat conduction between the sensing part and the wire of contact temperature sensor A. : In the formula, This represents the composite surface heat transfer coefficient between the outer surface of the optical fiber lead and the fluid and environment. This indicates the diameter of the lead wire of the contact temperature sensor. This represents the thermal conductivity of the lead material of contact temperature sensor A. This indicates the temperature at the distal end of the lead of contact temperature sensor A. Represents the hyperbolic tangent function. Indicates the length of the optical fiber lead. d represents the convective heat transfer coefficient between the lead of contact temperature sensor A and the fluid on one side of the measured high-temperature solid wall. y Let be the diameter of the lead wire of temperature sensor A.

4. The method for temperature measurement correction of a high-temperature solid wall surface according to claim 1, characterized in that, The convective heat transfer coefficient between the high-temperature solid wall and the fluid in step 3 Represented as: ， ， ， In the formula, Indicates the length of the fluid channel. This represents the cross-sectional area of ​​the channel for flow. This indicates the length of the contact surface between the fluid channel wall and the fluid. This represents thermophysical property parameters.

5. The method for temperature measurement correction of a high-temperature solid wall surface according to claim 4, characterized in that, The heat conduction differential equation in step 5 is as follows: In the formula, This indicates the deviation temperature within the measured high-temperature solid. Indicates the distance to the vertical axis. This represents the distance from the longitudinal direction of the measured high-temperature solid wall to the origin of the coordinate system.

Images