Method for calculating rarefied flow field temperature through convective heat flow and Gordon meter surface temperature

Abstract

The invention discloses a method for calculating the temperature of a rarefied flow field through convective heat flow and the surface temperature of a Gordon meter, and the method is used for measuring the incoming flow temperature of a rarefied fluid wind tunnel, and comprises the steps: installing the Gordon meter and a radiation heat flow meter on a moving motor at a certain interval, and controlling a measurement point through the moving motor, the measuring point is an area covered by the incoming flow direction; after a measuring point is selected, under the same working condition, a moving motor sequentially measures the total heat flow Q (average value) and the pure radiation heat flow qr of the measuring point, the heat flow average value Qc = Q-qr of convective heat transfer is obtained, and an infrared pyrometer is used for measuring the center temperature Tr = 0 of a Gordon meter; and calculating the incoming flow temperature Tf and the convective heat transfer coefficient h of the current measurement point according to the convective heat flow Qc and the constantan foil center temperature Tr = 0 of the Gordon meter. According to the invention, a simple structure is used for replacing a complicated measurement system of a conventional rarefied wind tunnel temperature measurement method, and the problem that in a highly rarefied wind tunnel, the signal of a spectrum temperature measurement method is weak, and the temperature measured by a thermocouple is difficult to reflect the actual temperature of a flow field is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of rarefied fluid wind tunnel testing, and in particular relates to a method for calculating rarefied flow field temperature based on convective heat flux and Gordon meter surface temperature. Background Art

[0002] Rarefied fluid wind tunnels can be used to simulate and measure near-space and even very low-orbit environments, providing key data for aircraft design and performance evaluation, and are widely used in aerospace and other fields. In the use of rarefied fluid wind tunnels, in order to correctly reflect the heat flow, resistance and other parameters of the aircraft in the real environment, it is essential to measure the temperature of the rarefied flow. Conventional rarefied wind tunnel temperature measurement methods have complex measurement systems, weak signals and high costs. Summary of the invention

[0003] In view of the problems existing in the prior art, the present invention proposes a method for calculating the temperature of a rarefied flow field from convective heat flux and the surface temperature of a Gordon meter, aiming to solve the problems of complex measurement system, weak signal and high cost of conventional wind tunnel temperature measurement methods.

[0004] The present invention adopts the following technical solutions to solve the technical problems:

[0005] A method for calculating the temperature of a rarefied flow field from convective heat flux and Gordon meter surface temperature, the method being used for measuring the incoming flow temperature in a rarefied fluid wind tunnel, and comprising the following steps:

[0006] Step 1: Install the Gordon meter and the radiation heat flow meter on the mobile motor at a certain distance, and control the measuring point by the mobile motor, wherein the measuring point is the area covered by the incoming flow direction;

[0007] Step 2: After selecting the measurement point, under the same working conditions, move the motor to measure the total heat flux Q (average value) and pure radiation heat flux q of the measurement point in turn. r , we get the heat flux (average value) Q of convective heat transfer c =Qq r The center temperature T of the Gordon meter is measured using an infrared pyrometer r＝0 ;

[0008] Step 3: Heat flow Q through convection c Gordon-Gecko copper foil center temperature T r＝0 , calculate the incoming flow temperature T at the current measuring point f The convective heat transfer coefficient h is assumed to be uniform along the radial direction of the copper foil.

[0009] Furthermore, the step 3 of heat flux Q c Gordon-Gecko copper foil center temperature T r＝0 , calculate the incoming flow temperature T at the current measuring pointf And the convection heat transfer coefficient h, the specific process is as follows:

[0010] 1) By solving the steady-state heat transfer equation, we can obtain the inflow temperature T f Theoretical expression of the surface temperature of the copper foil with the convection heat transfer coefficient h T(r)

[0011] 2) Using the theoretical expression of the circular foil surface temperature T(r), by integrating the single-point convection heat flux on the surface of the copper foil, the temperature T f Theoretical expression of the average convective heat flux Q with the convective heat transfer coefficient h c ;

[0012] 3) The center temperature T of copper foil is measured by Gordon meter r＝0 Get the incoming flow temperature T f Theoretical expression of the surface temperature of the deformed circular foil △T with the convection heat transfer coefficient h;

[0013] 4) Solving the above two equations 2) and 3) can obtain the convection heat transfer coefficient h and the flow field temperature T near the wall surface. f .

[0014] Furthermore, in the step 3 process 1), the steady-state heat transfer equation is solved to obtain the temperature T f The theoretical expression of the surface temperature of the copper foil T(r) with the convection heat transfer coefficient h is as follows:

[0015] A. According to the steady-state heat conduction equation and the boundary conditions of the Gordon meter, the steady-state heat conduction equation of the Gordon meter is obtained:

[0016]

[0017] Among them, r, T(r), and q are all unknown quantities. 0 , δ, R, and λ are all known quantities;

[0018] Among the unknown quantities, r is the independent variable, which is the distance measured from the center of the foil in the radial direction; T(r) is the temperature at position r on the surface of the foil; q is the total heat at a single point;

[0019] Among the known quantities, T 0 is the temperature of the edge of the Constantan foil on the Gordon meter, δ is the thickness of the Constantan foil, R is the radius of the Constantan foil, and the thermal conductivity λ of the Constantan foil is a linear function of temperature;

[0020] λ is the thermal conductivity, and assuming that the thermal conductivity λ is uniform at different radial positions on the foil surface, the average temperature on the radius of the circular foil is used. describe: When T 1 =0℃,λ 0=20.9W / (m℃), b=0.00231℃ -1 , is a known quantity, and defines

[0021] B. Obtain the total heat flow q value of formula (1)

[0022] ① Total heat flux at a single point on the circular foil surface due to convection and radiation heat transfer:

[0023] q=q c +q r ; (2)

[0024] q r The radiative heat flux is known;

[0025] ② The single point convection heat flux q c Using the other three variables and h, T f , T(r) represents

[0026] q c =h(T f -T(r)) (3)

[0027] T f is the incoming flow temperature T f , h is the convective heat transfer coefficient, T(r) is the temperature at position r on the foil surface; q c is an unknown quantity;

[0028] C. The theoretical expression of the surface temperature of the round foil T(r) is obtained by using equations (1), (2) and (3):

[0029]

[0030] Among them, I 0 (m ξ r) is about m ξ r's zeroth-order modified Bessel function of the first kind, m ξ =(h / ξλ 0 δ) 1 / 2 is a function of h, which is an unknown variable; T(r) is the temperature of the Gordon gauge at r as the dependent variable, r is the distance to the center of the Gordon gauge as the independent variable, T f The incoming flow temperature is unknown, h is the convective heat transfer coefficient is unknown, and q r is the radiation heat flux is known, T 0 is the edge temperature of the Gordon-German copper foil, which can be obtained by equation (6), and R is the radius of the Gordon-German copper foil, which is known.

[0031] In the process 2) of step 3, the theoretical expression T(r) of the round foil surface temperature is used to integrate the single-point convection heat flow on the surface of the copper foil to obtain the temperature Tf Theoretical expression of the average convective heat flux Q with the convective heat transfer coefficient h c ; The details are as follows:

[0032] A. By measuring the voltage output E, we can obtain ΔT in equation (5): The voltage output E of the thermoelectric electromotive force of the copper-constantan thermocouple formed by the Gordon heat flow meter is a function of the temperature difference ΔT:

[0033] E=kΔT(1+gΔT) (5)

[0034] Where, k = 0.0381mV / °C, g = 0.0012°C -1 , the voltage output E can be obtained through experiments;

[0035] B. Substituting T(r) in equation (4) into equation (6) yields the average heat flux density Q for convective heat transfer: c :

[0036] The average value of the heat flux density of convection heat transfer is Q c It can be obtained by the following integral:

[0037]

[0038] Among them, T in formula (4) f It can be eliminated in formula (6); I 1 (m ξ r) is m ξ The first-order modified Bessel function of the first kind, I 0 (m ξ r) is about m ξ r's zeroth-order modified Bessel function of the first kind, m ξ =(h / ξλ 0 δ) 1 / 2 is an unknown number, and the temperature difference between the edge and center of the Gordon-Gecko copper foil ΔT=T r＝0 -T 0 is a known quantity, T f is the incoming flow temperature is unknown, h is the convective heat transfer coefficient is unknown, T(r) is the temperature at position r on the foil surface is the dependent variable of the independent variable r;

[0039] Furthermore, the center temperature T of the copper foil is measured by Gordon Gauge in step 3) r＝0 Get the incoming flow temperature T f Theoretical expression of the surface temperature of the deformed circular foil △T with the convection heat transfer coefficient h;

[0040] 1) The ΔT obtained by formula (6) and the known center temperature T of the copper foil on the surface of the Gordon meter r＝0 , and obtain the edge temperature T of the Gordon-Gecko copper foil 0=T r＝0 -ΔT;

[0041] 2) Transform equation (4) to obtain equation (7), let r = 0 in equation (4), and replace the first T on the right side of equation (4) with 0 Moving to the left, we get:

[0042]

[0043] Due to m ξ is a function of h, so equation (6) and equation (7) only contain two unknowns T f and h; The above two equations can be used to obtain the convective heat transfer coefficient h and the flow field temperature T near the wall surface f .

[0044] Advantages and effects of the present invention

[0045] 1. Compared with the conventional rarefied wind tunnel temperature measurement method, the present invention replaces the complex measurement system of the conventional rarefied wind tunnel temperature measurement method with a simple structure (radiation heat flux meter, Gordon meter, infrared pyrometer, bidirectional moving motor, and related algorithms), thereby solving the problem that in a highly rarefied wind tunnel, the signal of the spectral temperature measurement method is weak and the temperature measured by the thermocouple is difficult to reflect the actual temperature of the flow field. 2. Compared with the conventional rarefied fluid wind tunnel temperature measurement method, the present invention uses the average value of the total heat flux measured by the Gordon meter minus the radiation heat flux measured by the radiation heat flux meter, thereby eliminating the radiation interference generated by the rarefied fluid wind tunnel generator. The conventional rarefied fluid wind tunnel temperature measurement method does not take the interference of radiation heating into account, so the present invention has a more accurate flow field temperature measurement result. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 This is a schematic diagram of the rarefied wind tunnel temperature measurement system; Figure 2 This is the surface temperature distribution diagram of the Gordon meter structure; Figure 3 The flowchart is a method for calculating the rarefied flow field temperature from the convective heat flux and the Gordon meter surface temperature. DETAILED DESCRIPTION

[0047] Design principle of the present invention

[0048] 1. Innovation of the present invention: The innovation lies in using a relatively simple method to measure the flow field temperature T f Specifically, the method of calculating the temperature of the rarefied flow field is organically combined with a radiation heat flux meter, a Gordon meter, an infrared pyrometer, and a bidirectional moving motor. By using the radiation heat flux q r and Gordon-Geckon copper foil center temperature T r＝0The average convective heat flux Q is obtained by measuring c (heat flux (average value) Q c =Qq r ), and Gordon-Gecko copper foil center temperature T r＝0 , and then calculate the incoming flow temperature T at the current measuring point through these two known numbers f The convection heat transfer coefficient h solves the problems of complex measurement system, weak signal and high cost of conventional rarefied wind tunnel temperature measurement method. c , which comes from the total heat flux Q minus the radiation heat flux q r , the total heat flux Q is obtained by measurement; the radiation heat flux q of the two known numbers r From a radiation heat flux meter.

[0049] 2. Design principle of the present invention: The present invention is realized by establishing two equations to obtain two parameters: the incoming flow temperature T f and the convection heat transfer coefficient h, these two equations are formula (6) and formula (7);

[0050] Formula (6) is the average heat flux Q of the known parameters of convective heat transfer obtained by combining formulas (1)-(5) with the measured heat flux c get;

[0051] Formula (7) is established on the basis of formula (4) and uses the known parameter Gordon Gauge copper foil center temperature T obtained by measurement. r＝0 , and finally get the modified formula (4), that is, formula (7). The specific steps to get formula (7) are: First, substitute T (r) in formula (4) into formula (6) to get the average heat flux density Q of convective heat transfer c , which is formula (6), the unknown number of formula (6) is h; second, formula (6) △T is obtained by formula (5), at this time, formula (6) only has one unknown number h; third, since △T is obtained by formula (5), T r＝0 It is also measured, so the T on the right side of formula (4) can be 0 Move to the left side of formula (4) to form △T, that is, △T=T r＝0 -T 0 , thus completing the transformation of formula (4) to obtain formula (7). Since both formula (6) and formula (7) contain only two unknowns: the incoming flow temperature T f and the convection heat transfer coefficient h, so solving these two equations can yield two unknowns: the incoming flow temperature T f And the convection heat transfer coefficient h.

[0052] Based on the above principle, the present invention designs a method for calculating the rarefied flow field temperature from the convective heat flux and the Gordon meter surface temperature, such as Figure 1-3 As shown, the method is used in a rarefied fluid wind tunnel to measure the incoming flow temperature, and is characterized in that it comprises the following steps:

[0053] Step 1: Install the Gordon meter and the radiation heat flow meter on the mobile motor at a certain distance, and control the measuring point by the mobile motor, wherein the measuring point is the area covered by the incoming flow direction;

[0054] Step 2: After selecting the measurement point, under the same working conditions, move the motor to measure the total heat flux Q (average value) and pure radiation heat flux q of the measurement point in turn. r , we get the heat flux (average value) Q of convective heat transfer c =Qq r The center temperature T of the Gordon meter is measured using an infrared pyrometer r＝0 ;

[0055] Step 3: Heat flow Q through convection c Gordon-Gecko copper foil center temperature T r＝0 , calculate the incoming flow temperature T at the current measuring point f And the convection heat transfer coefficient h, assuming that the convection heat transfer coefficient h is uniform along the radial direction of the copper foil.

[0056] Furthermore, the step 3 of heat flux Q c Gordon-Gecko copper foil center temperature T r＝0 , calculate the incoming flow temperature T at the current measuring point f And the convection heat transfer coefficient h, the specific process is as follows:

[0057] 1) By solving the steady-state heat transfer equation, we can obtain the inflow temperature T f Theoretical expression of the surface temperature of the copper foil with the convection heat transfer coefficient h T(r)

[0058] 2) Using the theoretical expression of the circular foil surface temperature T(r), by integrating the single-point convection heat flux on the surface of the copper foil, the temperature T f Theoretical expression of the average convective heat flux Q with the convective heat transfer coefficient h c ;

[0059] 3) The center temperature T of copper foil is measured by Gordon meter r＝0 Get the incoming flow temperature T f Theoretical expression of the surface temperature of the deformed circular foil △T with the convection heat transfer coefficient h;

[0060] 4) Solving the above two equations 2) and 3) can obtain the convection heat transfer coefficient h and the flow field temperature T near the wall surface. f .

[0061] Furthermore, in the step 3 process 1), the steady-state heat transfer equation is solved to obtain the temperature T f The theoretical expression of the surface temperature of the copper foil T(r) with the convection heat transfer coefficient h is as follows:

[0062] A. According to the steady-state heat conduction equation and the boundary conditions of the Gordon meter, the steady-state heat conduction equation of the Gordon meter is obtained:

[0063]

[0064] Among them, r, T(r), and q are all unknown quantities. 0 , δ, R, and λ are all known quantities;

[0065] Among the unknown quantities, r is the independent variable, which is the distance measured from the center of the foil in the radial direction; T(r) is the temperature at position r on the surface of the foil; q is the total heat at a single point;

[0066] Among the known quantities, T 0 is the temperature of the edge of the Constantan foil on the Gordon meter, δ is the thickness of the Constantan foil, R is the radius of the Constantan foil, and the thermal conductivity λ of the Constantan foil is a linear function of temperature;

[0067] λ is the thermal conductivity, and assuming that the thermal conductivity λ is uniform at different radial positions on the foil surface, the average temperature on the radius of the circular foil is used. describe: When T 1 =0℃,λ 0 =20.9W / (m℃), b=0.00231℃ -1 , is a known quantity, and defines

[0068] Additional notes:

[0069] This embodiment assumes that the convective heat transfer coefficient h is uniform at different radial positions on the foil surface, and the thermal conductivity λ is also uniform at different radial positions on the foil surface. This assumption is based on the fact that the temperature difference between the center and the edge of the circular foil is small due to the small heat flow in the rarefied wind tunnel, so the assumption that the convective heat transfer coefficient h and the thermal conductivity λ are constants to be determined is feasible.

[0070] B. Obtain the total heat flow q value of formula (1)

[0071] ① Total heat flux at a single point on the circular foil surface due to convection and radiation heat transfer:

[0072] q=q c +q r ; (2)

[0073] q r The radiative heat flux is known;

[0074] ② The single point convection heat flux q c Using the other three variables and h, T f , T(r) represents

[0075] q c =h(T f -T(r)) (3)

[0076] T f is the incoming flow temperature T f , h is the convective heat transfer coefficient, T(r) is the temperature at position r on the foil surface; q c is an unknown quantity;

[0077] C. The theoretical expression of the surface temperature of the round foil T(r) is obtained by using equations (1), (2) and (3):

[0078]

[0079] Among them, I 0 (m ξ r) is about m ξ r's zeroth-order modified Bessel function of the first kind, m ξ =(h / ξλ 0 δ) 1 / 2 is a function of h, which is an unknown variable; T(r) is the temperature of the Gordon gauge at r as the dependent variable, r is the distance to the center of the Gordon gauge as the independent variable, T f The incoming flow temperature is unknown, h is the convective heat transfer coefficient is unknown, and q r is the radiation heat flux is known, T 0 is the edge temperature of the Gordon-German copper foil, which can be obtained by equation (6), and R is the radius of the Gordon-German copper foil, which is known.

[0080] Furthermore, the theoretical expression T(r) of the round foil surface temperature is used in the process 2) of step 3 to obtain the heat flux containing the incoming flow temperature T by integrating the single-point convection heat flux on the surface of the copper foil. f Theoretical expression of the average convective heat flux Q with the convective heat transfer coefficient h c ; The details are as follows:

[0081] A. By measuring the voltage output E, we can obtain ΔT in equation (5): The voltage output E of the thermoelectric electromotive force of the copper-constantan thermocouple formed by the Gordon heat flow meter is a function of the temperature difference ΔT:

[0082] E=kΔT(1+gΔT) (5)

[0083] Where, k = 0.0381mV / °C, g = 0.0012°C -1 , the voltage output E can be obtained through experiments;

[0084] B. Substituting T(r) in equation (4) into equation (6) yields the average heat flux density Q for convective heat transfer: c :

[0085] The average value of the heat flux density of convection heat transfer is Q c It can be obtained by the following integral:

[0086]

[0087] Among them, T in formula (4) f It can be eliminated in formula (6); I 1 (m ξ r) is m ξ The first-order modified Bessel function of the first kind, I 0 (m ξ r) is about m ξ r's zeroth-order modified Bessel function of the first kind, m ξ =(h / ξλ 0 δ) 1 / 2 is an unknown number, and the temperature difference between the edge and center of the Gordon-Gecko copper foil ΔT=T r＝0 -T 0 is a known quantity, T f is the incoming flow temperature is unknown, h is the convective heat transfer coefficient is unknown, T(r) is the temperature at position r on the foil surface is the dependent variable of the independent variable r;

[0088] Furthermore, the center temperature T of the copper foil is measured by Gordon Gauge in step 3) r＝0 Get the incoming flow temperature T f Theoretical expression of the surface temperature of the deformed circular foil △T with the convection heat transfer coefficient h;

[0089] 1) The ΔT obtained by formula (6) and the known center temperature T of the copper foil on the surface of the Gordon meter r＝0 , and obtain the edge temperature T of the Gordon-Gecko copper foil 0 =T r＝0 -ΔT;

[0090] 2) Transform equation (4) to obtain equation (7), let r = 0 in equation (4), and replace the first T on the right side of equation (4) with 0 Moving to the left, we get:

[0091]

[0092] Due to m ξ is a function of h, so equation (6) and equation (7) only contain two unknowns T fand h; The above two equations can be used to obtain the convective heat transfer coefficient h and the flow field temperature T near the wall surface f .

[0093] It should be emphasized that the above specific embodiments are merely explanations of the present invention, and they are not limitations of the present invention. After reading this specification, those skilled in the art can make modifications to the above embodiments without any creative contribution as needed, but as long as they are within the scope of the claims of the present invention, they are protected by patent law.

Claims

1. A method for calculating the temperature of a rarefied flow field from convective heat flux and Gordon meter surface temperature, the method being used for measuring the incoming flow temperature in a rarefied fluid wind tunnel, characterized in that: The following steps are involved: Step 1: Install the Gordon meter and the radiation heat flow meter on the mobile motor at a certain distance, and control the measuring point by the mobile motor, wherein the measuring point is the area covered by the incoming flow direction; Step 2: After selecting the measurement point, under the same working conditions, move the motor to measure the total heat flux average value Q and the pure radiation heat flux q of the measurement point in turn. r , we get the average heat flux Q of convective heat transfer c =Qq r The center temperature T of the Gordon meter is measured using an infrared pyrometer r＝0 ; Step 3: Heat flow Q through convection c Gordon-Gecko copper foil center temperature T r＝0 , calculate the incoming flow temperature T at the current measuring point f And the convection heat transfer coefficient h, assuming that the convection heat transfer coefficient h is uniform along the radial direction of the copper foil.

2. According to the method of calculating the rarefied flow field temperature by the convective heat flux and the Gordon meter surface temperature according to claim 1, the step 3 is to calculate the rarefied flow field temperature by the convective heat flux Q c Gordon-Gecko copper foil center temperature T r＝0 , calculate the incoming flow temperature T at the current measuring point f And the convection heat transfer coefficient h, the specific process is as follows: 1) By solving the steady-state heat transfer equation, we can obtain the inflow temperature T f Theoretical expression of the surface temperature of the copper foil with the convection heat transfer coefficient h T(r) 2) Using the theoretical expression of the circular foil surface temperature T(r), by integrating the single-point convection heat flux on the surface of the copper foil, we can obtain the temperature T f Theoretical expression of the average convective heat flux Q with the convective heat transfer coefficient h c ; 3) The center temperature T of copper foil is measured by Gordon meter r＝0 Get the incoming flow temperature T f Theoretical expression of the surface temperature of the deformed circular foil △T with the convection heat transfer coefficient h; 4) Solving the above two equations 2) and 3) can obtain the convection heat transfer coefficient h and the flow field temperature T near the wall surface. f .

3. According to the method of calculating the rarefied flow field temperature by convective heat flux and Gordon meter surface temperature according to claim 1, the step 3 process 1) is to solve the steady-state heat transfer equation to obtain the temperature T of the incoming flow. f The theoretical expression of the surface temperature of the copper foil T(r) with the convection heat transfer coefficient h is as follows: A. According to the steady-state heat conduction equation and the boundary conditions of the Gordon meter, the steady-state heat conduction equation of the Gordon meter is obtained: in, r, T(r), q are all unknown quantities, T0, δ, R, λ are all known quantities; Among the unknown quantities, r is the independent variable, which is the distance measured from the center of the foil in the radial direction; T(r) is the temperature at position r on the surface of the foil; q is the total heat at a single point; Among the known quantities, T0 is the temperature of the edge of the Constantan foil in the Gordon meter, δ is the thickness of the Constantan foil, R is the radius of the Constantan foil, and the thermal conductivity λ of the Constantan foil is a linear function of temperature; λ is the thermal conductivity, and assuming that the thermal conductivity λ is uniform at different radial positions on the foil surface, the average temperature on the radius of the circular foil is used. describe: When T1 = 0°C, λ0 = 20.9W / (m°C), b = 0.00231°C -1 , is a known quantity, and defines B. Obtain the total heat flow q value of formula (1) ① Total heat flux at a single point on the circular foil surface due to convection and radiation heat transfer: q=q c +q r ; (2) q r The radiative heat flux is known; ② The single point convection heat flux q c Using the other three variables and h, T f , T(r) represents q c =h(T f -T(r)) (3) T f is the incoming flow temperature T f , h is the convective heat transfer coefficient, T(r) is the temperature at position r on the foil surface; q c is an unknown quantity; C. The theoretical expression of the surface temperature of the round foil T(r) is obtained by using equations (1), (2) and (3): Among them, I0(m ξ r) is about m ξ r's zeroth-order modified Bessel function of the first kind, m ξ =(h / ξλ0δ) 1 / 2 is a function of h, which is an unknown variable; T(r) is the temperature of the Gordon gauge at r as the dependent variable, r is the distance to the center of the Gordon gauge as the independent variable, T f The incoming flow temperature is unknown, h is the convective heat transfer coefficient is unknown, and q r is the radiation heat flux which is known, T0 is the edge temperature of the Gordon-German copper foil which can be obtained by equation (6), and R is the radius of the Gordon-German copper foil which is known.

4. According to the method for calculating the rarefied flow field temperature by convective heat flux and Gordon meter surface temperature according to claim 1, the theoretical expression T(r) of the circular foil surface temperature is used in the process 2) of step 3 to obtain the temperature T containing the incoming flow by integrating the single-point convective heat flux on the surface of the copper foil. f Theoretical expression of the average convective heat flux Q with the convective heat transfer coefficient h c ; The details are as follows: A. By measuring the voltage output E, we can find ΔT in equation (5): The voltage output E of the thermoelectric electromotive force of the copper-constantan thermocouple formed by the Gordon heat flow meter is a function of the temperature difference ΔT: E=kΔT(1+gΔT) (5) in, k=0.0381mV / ℃, g=0.0012℃ -1 , the voltage output E can be obtained through experiments; B. Substituting T(r) in equation (4) into equation (6) yields the average heat flux density Q for convective heat transfer: c : The average value of the heat flux density of convection heat transfer is Q c It can be obtained by the following integral: Among them, T in formula (4) f It can be eliminated in equation (6); I1(m ξ r) is m ξ The first-order first-kind modified Bessel function of r, I0(m ξ r) is about m ξ r's zeroth-order modified Bessel function of the first kind, m ξ =(h / ξλ0δ) 1 / 2 is an unknown number, and the temperature difference between the edge and center of the Gordon-Gecko copper foil ΔT=T r＝0 -T0 is a known quantity, T f is the incoming flow temperature which is unknown, h is the convective heat transfer coefficient which is unknown, and T(r) is the temperature at position r on the foil surface which is the dependent variable of the independent variable r.

5. According to the method for calculating the rarefied flow field temperature by using the convective heat flux and the Gordon meter surface temperature according to claim 1, the central temperature T of the copper foil of the Gordon meter is measured in step 3) r＝0 Get the incoming flow temperature T f Theoretical expression of the surface temperature of the deformed circular foil △T with the convection heat transfer coefficient h; 1) The ΔT obtained by formula (5) and the known center temperature T of the copper foil on the surface of the Gordon meter r＝0 , we get the edge temperature of the copper foil T0 = T r＝0 -ΔT; 2) Transform equation (4) to get equation (7), let r = 0 in equation (4), and move the first T0 on the right side of equation (4) to the left side, and we can get: Due to m ξ is a function of h, so equation (6) and equation (7) only contain two unknowns T f and h; The above two equations can be used to obtain the convective heat transfer coefficient h and the flow field temperature T near the wall surface f .

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