A dynamic total temperature probe comb of thin film platinum resistance for measuring unsteady flow fields

Abstract

The present application belongs to the technical field of dynamic temperature test, and particularly relates to a dynamic total temperature probe comb of a thin-film platinum resistance for measuring a non-steady flow field, comprising a probe support rod, a positioning block, a probe head, a thin-film platinum resistance, a circular pipeline and a lead hole. The probe support rod has the circular pipeline inside, and the tail of the probe support rod has the positioning block. The probe head is a cylinder with a circular truncated cone head, the number of which is determined according to the measurement requirement and is at least three, and the probe heads are fixed at different spanwise measurement positions of the probe support rod respectively. The center of the top surface of the circular truncated cone head of the probe head is provided with the lead hole, the lead hole is communicated with the circular pipeline, the thin-film platinum resistance is installed above the lead hole, and the lead wire of the thin-film platinum resistance is led out from the tail of the probe through the lead hole and the circular pipeline. The dynamic total temperature probe comb of the thin-film platinum resistance for measuring the non-steady flow field is calibrated and is suitable for measuring the distribution of the dynamic total temperature of the non-steady flow field of a turbomachine along the height direction of a blade. Compared with the existing dynamic temperature probe, the dynamic total temperature probe comb of the thin-film platinum resistance can simultaneously measure the inflow parameters of multiple spatial positions, greatly shortens the measurement time and reduces the test cost.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of dynamic temperature test, and particularly relates to a dynamic total temperature probe comb of a thin-film platinum resistance for measuring a non-steady flow field, which is suitable for measuring transient information of a three-dimensional non-steady flow field in an impeller machine, and the core is to quickly and accurately measure and monitor the transient temperature distribution along the height direction of the three-dimensional non-steady flow field of the impeller machine.

[0002] Compared with the existing temperature probe for measuring a three-dimensional flow field, the temperature probe does not need to change the position of the measuring point by means of a probe displacement mechanism, and can complete the measurement of the temperature distribution along the height direction of the three-dimensional non-steady flow field of the impeller machine in an instant, and reduce the test cost. BACKGROUND

[0003] The three-dimensional flow field at the inlet, outlet and inter-stage of the impeller machine is essentially non-steady due to fluid viscosity, shock wave, rotation of the rotor, existence of the blade tip clearance, staggered arrangement of the moving and stationary blade rows, etc. It is very difficult to quickly and accurately obtain the temperature field at the inlet, outlet and inter-stage of the impeller machine varying with time. The impeller machine needs to measure the temperature distribution along the height direction of the blade due to the temperature distortion of the inlet air, and in some impeller machine tests, the effective test time is short, only a few minutes or even a few seconds, and the existing temperature probe cannot complete the measurement of the three-dimensional flow field parameter distribution along the height direction of the test piece at the inlet and outlet in a few seconds. Therefore, in order to quickly and accurately obtain the transient temperature field at the inlet, outlet and inter-stage of the impeller machine, a more targeted test method must be developed.

[0004] At present, a thermocouple temperature probe is generally used, and the probe is driven to different height positions by means of a probe displacement mechanism to be measured respectively. Since it is single-point measurement, the probe needs to be moved to complete multi-point measurement, the experimental measurement time is long, and the experimental cost is high. The thermocouple temperature sensor is often used to obtain the dynamic temperature signal of the flow field, but due to the limited frequency, the highest frequency response of the filament thermocouple temperature sensor cannot completely meet the test requirements of the transient temperature field at the inlet, outlet and inter-stage of the impeller machine under special working conditions, and compared with the thin-film platinum resistance temperature sensor, the accuracy of the thermocouple is lower. During a long time of use, the thermocouple may drift due to material aging and thermoelectric effect, leading to an increase in measurement error, and being easily affected by environmental factors.

[0005] Therefore, in order to quickly and accurately obtain the transient temperature field at the inlet, outlet and inter-stage of the impeller machine, it is urgent to develop a test technology with fast speed, high accuracy, resistance to airflow scouring, small spatial resolution and small disturbance to the flow field, so as to realize accurate measurement of the dynamic temperature of the non-steady flow field, and provide reliable measurement means and technical support for high-performance design and optimization of the impeller machine. SUMMARY

[0006] This invention discloses a dynamic total temperature probe comb for measuring unsteady flow fields using a thin-film platinum resistance thermometer, comprising a probe support, a positioning block, probes, a thin-film platinum resistance thermometer, a circular tube, and lead holes. The probe support contains a circular tube, and the tail of the probe support has a positioning block. The probes are cylinders with frustum-shaped heads; the number is determined according to the measurement requirements, but at least three, and they are fixed at different measurement positions along the span of the probe support. A lead hole is located at the center of the top surface of the frustum of the probe, communicating with the circular tube. A thin-film platinum resistance thermometer is installed above the lead hole, and the leads of the thin-film platinum resistance thermometer pass through the lead hole and the circular tube, exiting from the tail of the probe.

[0007] A wide-range calibration of a dynamic total temperature probe comb for measuring unsteady flow fields using a thin-film platinum resistance thermometer was performed in a calibration wind tunnel. The calibration speed range was Mach 0.1 to Mach 2, the deflection angle range was -80° to 80°, and the pitch angle range was -40° to 40°. During the wind tunnel calibration test, temperature measurements were performed simultaneously using two thin-film platinum resistance thermometers. The two resistance thermometers were supplied with different constant currents by a signal generator. The two resistance thermometers had different initial temperatures but the same convective heat transfer surface heat transfer coefficient h. The ratio of the heat flux densities of the two thin-film platinum resistance thermometers under different operating conditions could be obtained. The ratio of the heat flux densities was defined as S and satisfied by the following equation:

[0008] q1=h(T t -T w1 )

[0009] q2=h(T t -T w2 )

[0010]

[0011] In the formula, q1 and q2 represent the heat flux density of the thin-film platinum resistance thermometer, in W / m³. 2 Tw1, Tw2 — Temperature measured by thin-film platinum resistance thermometer, in K; Tt — Total incoming flow temperature of the calibration wind tunnel, in K. The ratio S of heat flux density under different calibration conditions can be obtained through the above calibration method.

[0012] During the test measurement, under known incoming flow conditions, the corresponding heat flux density ratio S can be obtained from the calibration data. Using the measured Tw1 and Tw2 data, the total temperature T of the measured airflow can be calculated using the following formula. g :

[0013]

[0014] This invention is based on a dynamic total temperature probe using a dual-film platinum resistance thermometer. By obtaining the temperature analytical transfer function coefficients through calibration experiments, the temperature transfer function of the dynamic total temperature probe using the dual-film platinum resistance thermometer is constructed, and the total temperature of the airflow in the measured flow field is reconstructed, which can greatly improve the frequency response and measurement accuracy of the dynamic total temperature probe.

[0015] The application provides a dynamic total temperature probe comb of a thin film platinum resistance for measuring an unsteady flow field, and aims to solve the following technical problems: 1. The precision of the existing dynamic temperature probe comb is insufficient; 2. The existing temperature probe comb is limited by the low frequency response of the traditional dynamic temperature sensor; 3. The existing temperature probe cannot complete the measurement of the temperature parameter distribution along the blade height direction of the inlet and outlet three-dimensional flow field of a turbomachinery test piece within several seconds, compared with the existing temperature probe, the dynamic total temperature probe comb of the thin film platinum resistance can simultaneously measure the inflow parameters of multiple spatial positions, can shorten the measurement time to the maximum extent, can complete the measurement of the inflow temperature distribution along the blade height direction of the inlet and outlet three-dimensional flow field of the turbomachinery test piece, and can reduce the test cost.

[0016] The technical solution of the application is as follows:

[0017] 1. A dynamic total temperature probe comb of a thin film platinum resistance for measuring an unsteady flow field, which is composed of a probe support rod (1), a positioning block (2), a probe head (3), a right thin film platinum resistance (4), a left thin film platinum resistance (5), a circular pipeline (6), and a lead hole (7), characterized in that the probe support rod (1) is internally provided with the circular pipeline (6), the tail part of the probe support rod (1) is provided with the positioning block (2), the probe head (3) is a cylinder with a circular truncated cone head, the number of the probe heads (3) is determined according to the measurement requirement and is at least three, the probe heads (3) are fixed at different spanwise measurement positions of the probe support rod (1) respectively, the center of the top surface of the circular truncated cone of the probe head (3) is provided with the lead hole (7), the lead hole (7) is communicated with the circular pipeline (6), the right thin film platinum resistance (4) and the left thin film platinum resistance (5) are installed above the lead hole (7), the lead wires of the right thin film platinum resistance (4) and the left thin film platinum resistance (5) pass through the lead hole (7) and the circular pipeline (6) and are led out from the tail part of the probe.

[0018] 2. The probe support rod (1) is a cylinder, the diameter d of the cylinder is in the range of 2 mm to 10 mm; the circular pipeline (6) is internally provided in the probe support rod (2) along the axial direction, the diameter a of the circular pipeline is in the range of 1 mm to 8 mm, and the lead wires of the thin film platinum resistance pass through the lead hole and are connected with the external acquisition equipment through the circular pipeline (6).

[0019] 3. The diameter of the top surface of the circular truncated cone of the probe head (3) is 1 mm to 3 mm, the diameter of the bottom surface is 3 mm to 6 mm, the conical angle of the circular truncated cone of the probe head (1) is 30° to 100°, the probe head (3) can also be in the form of a pyramid, the probe head (3) is made of an insulating and heat insulating material, the heat conduction error during the measurement is reduced, and the measurement precision and the frequency response of the probe are improved.

[0020] 4. The center of the lead hole (7) is coincided with the center of the top surface of the circular truncated cone, and the diameter is 0.2 mm to 1 mm.

[0021] 5. The right thin film platinum resistance (4) and the left thin film platinum resistance (5) are installed on the lead hole, the thin film platinum resistance (4) adopts a micro four-wire thin film platinum resistance, the length is 0.5mm to 3mm, the width is 0.1mm to 1.5mm, the thickness is 0.01mm to 0.2mm, the four-wire measurement can effectively eliminate the influence of lead resistance on the measurement result, improve the measurement precision, and ensure the stability and accuracy of data.

[0022] 6. The installation distance of the right thin film platinum resistance (4) and the left thin film platinum resistance (5) is x, and the value range of x is 0.2mm≤x≤1mm.

[0023] 7. The positioning block (2) is a regular quadrilateral in cross section, and the cross section shape can be selected as a regular pentagon, a regular hexagon or a regular heptagon, the center line of the cross section and the axis of the probe support rod (1) are in the same plane, the thickness of the positioning block is a, and the value range of a is 2mm≤d≤10mm, the distance between the positioning block (2) and the bottom of the probe support rod (1) is b, and the value range of b is 5mm≤b≤20mm.

[0024] The dynamic total temperature probe comb of the thin film platinum resistance for measuring unsteady flow field has the following beneficial effects:

[0025] Beneficial effect one: the present application is calibrated through a standard wind tunnel, has high measurement precision and fast response speed, the sensing part is not affected by the structure of the probe itself, first senses the pulsation of the incoming flow, the flow field information is not distorted, and the measurement precision is high. Through the accurate calibration process, it is ensured that the response of the thin film platinum resistance at different temperature points is accurate and reliable, and only the incoming flow parameters need to be obtained during measurement, without understanding the physical property parameters of the measured medium.

[0026] Beneficial effect two: the present application is based on the design of double thin film platinum resistance, two pieces of thin film platinum resistance compensate each other when measuring temperature, two pieces of thin film platinum resistance compensate each other when measuring temperature, the temperature analysis transfer function coefficient is obtained through calibration test, the temperature measurement transfer function of the double thin film platinum resistance dynamic total temperature probe is constructed, and the total temperature of the measured flow field is reconstructed, which can greatly improve the frequency response of the dynamic total temperature probe. Compared with the traditional sensor, the double thin film platinum resistance can respond to temperature changes more quickly, adapt to the measurement demand of transient temperature field, especially in the complex working conditions of impeller inlet and outlet and interstage, the dynamic change of temperature can be accurately captured.

[0027] Beneficial effect three: the present application is suitable for the distribution of incoming flow parameters along the blade height direction of impeller mechanical inlet, outlet three-dimensional flow field. Compared with the existing temperature probe for measuring three-dimensional flow field, multiple spatial position incoming flow parameters can be measured at the same time, the measurement time can be shortened to the greatest extent, the measurement of three-dimensional flow field parameters along the blade height direction of impeller mechanical inlet, outlet can be completed, and the test cost is reduced.

[0028] Beneficial effect four: the probe of the present application has positioning function, the positioning block forms positioning reference, the probe is convenient and simple to install, no rotation is needed during measurement, no periodicity requirement for the measured flow field, wide application range. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 Figure 1 is a structural schematic diagram of a thin film platinum resistance dynamic total temperature probe comb for measuring subsonic unsteady flow field in an embodiment of the present application.

[0030] Figure 2 is a top view of Figure 1 .

[0031] Figure 3 is a side view of Figure 1 .

[0032] Figure 4 is a C-direction sectional view of Figure 1 .

[0033] Figure 5 is a B-direction sectional view of Figure 1 .

[0034] Figure 6 is an A-direction sectional view of Figure 1 .

[0035] Figure 7 is a local enlarged view of Figure 6 .

[0036] Wherein: 1-probe support rod, 2-positioning block, 3-probe head, 4-right thin film platinum resistance, 5-left thin film platinum resistance, 6-round pipe, 7-lead hole.

[0037] Figure 8 Figure 2 is a structural schematic diagram of a thin film platinum resistance dynamic total temperature probe comb for measuring transonic unsteady flow field in an embodiment of the present application.

[0038] Figure 9 is a top view of Figure 8 .

[0039] Figure 10 is a side view of Figure 8 .

[0040] Figure 11 is a C-direction sectional view of Figure 8 .

[0041] Figure 12 is a B-direction sectional view of Figure 8 .

[0042] Figure 13 is an A-direction sectional view of Figure 8 .

[0043] Figure 14 is Figure 13 a partial enlarged view of

[0044] Wherein: 1-probe strut, 2-positioning block, 3-probe, 4-right thin film platinum resistance, 5-left thin film platinum resistance, 6-round pipe, 7-lead hole. Specific implementation

[0046] The advantages and features of the present application will be more easily understood by those skilled in the art, and the protection scope of the present application will be more clearly defined, by combining the present application with the accompanying drawings and specific implementation cases.

[0047] As Figures 1 to 7 shown is a thin film platinum resistance dynamic total temperature probe comb for measuring subsonic unsteady flow field, which is composed of a probe strut (1), a positioning block (2), a probe (3), a right thin film platinum resistance (4), a left thin film platinum resistance (5), a round pipe (6), and a lead hole (7), and is characterized in that: the probe strut (1) has a round pipe (6) inside, the tail of the probe strut (1) has a positioning block (2), the probe (3) is a cylinder with a circular truncated cone head, the number is determined according to measurement requirements and is at least 3, and the probes (3) are fixed at different spanwise measurement positions of the probe strut (1) respectively, the center of the top surface of the circular truncated cone of the probe (3) is provided with a lead hole (7), the lead hole (7) is communicated with the round pipe (6), the right thin film platinum resistance (4) and the left thin film platinum resistance (5) are installed above the lead hole (7), and the lead wires of the right thin film platinum resistance (4) and the left thin film platinum resistance (5) are led out from the tail of the probe through the lead hole (6) and the round pipe (5);

[0048] The probe strut (1) is a cylinder, the diameter d of the cylinder is 10 mm; the probe strut (2) has a round pipe (6) inside along the axial direction, the diameter of the round pipe is a, and the value of a is 6 mm; and the lead wires of the thin film platinum resistance are connected with external collection equipment through the round pipe (6) after passing through the lead hole;

[0049] The diameter of the top surface of the probe (3) is 2 mm, the diameter of the bottom surface is 4 mm, the conical angle of the circular truncated cone of the probe (1) is 54°, the probe (3) is made of insulating and heat insulating material, the heat conduction error during measurement is reduced, and the measurement precision and frequency response of the probe are improved;

[0050] The center of the lead hole (7) coincides with the center of the top surface of the circular truncated cone, and the diameter is 0.5 mm;

[0051] The right thin film platinum resistance (4) and the left thin film platinum resistance (5) are installed on the lead hole, the right thin film platinum resistance (4) and the left thin film platinum resistance (5) adopt micro four-wire thin film platinum resistance, the length is 1mm, the width is 0.5mm, the thickness is 0.1mm, four-wire measurement can effectively eliminate the influence of lead resistance on measurement results, improve measurement precision, and guarantee data stability and accuracy;

[0052] The installation distance of the right thin film platinum resistance (4) and the left thin film platinum resistance (5) is x, and the value of x is 0.5mm;

[0053] The cross section of the positioning block (2) is a regular quadrilateral, the center line of the cross section and the center line of the thin film platinum resistance (4) are in the same plane as the axis of the probe support rod (1), the thickness of the positioning block is a, the value of a is 8mm, and the distance between the positioning block (2) and the bottom of the probe support rod (1) is b, the value of b is 20mm;

[0054] The application proposes a data processing method based on a thin film platinum resistance dynamic total temperature probe comb for measuring subsonic unsteady flow field, a wide range calibration is carried out on a thin film platinum resistance dynamic total temperature probe comb for measuring subsonic unsteady flow field in a calibration wind tunnel, the calibration speed range is 0.1 Mach to 1 Mach with an interval of 0.1 Mach, the deflection angle range is -80° to 80° with an interval of 5°, the pitch angle range is -40° to 40° with an interval of 5°, when the wind tunnel test calibration is carried out, two pieces of thin film platinum resistance are used to simultaneously measure the temperature, the two pieces of thin film platinum resistance are provided with different constant currents by using a signal generator, the initial temperatures of the two pieces of resistance are different, but the same convective heat transfer surface heat transfer coefficient h is possessed, so that the heat flux density ratio of the two pieces of thin film platinum resistance under different working conditions can be obtained, the heat flux density ratio is defined as S, and the following equation is satisfied:

[0055] q1=h(T t -T w1 )

[0056] q2=h(T t -T w2 )

[0057]

[0058] In the formula, q1, q2 are heat flux densities of thin film platinum resistance, unit: W / m 2 ; Tw1, Tw2 are temperatures measured by thin film platinum resistance, unit: K; Tt is total temperature of calibration wind tunnel inflow, unit: K, the heat flux density ratio S under different calibration working conditions can be obtained through the above calibration method;

[0059] When the test measurement is carried out, the corresponding heat flux density ratio S can be found from the calibration data under the known inflow working condition, the total temperature T of the measured air flow is calculated through the following formula by using the measured Tw1, Tw2 data:g :

[0060]

[0061] The application is based on a dynamic total temperature probe of double thin film platinum resistance, and the temperature analysis transfer function coefficient is obtained through calibration test, the temperature measurement transfer function of the dynamic total temperature probe of double thin film platinum resistance is constructed, and the airflow total temperature of the measured subsonic unsteady flow field is reconstructed, so that the frequency response and measurement precision of the dynamic total temperature probe can be greatly improved. Specific implementation method two:

[0063] The application will be described in detail below in combination with the drawings and specific implementation cases, so that the advantages and features of the application can be more easily understood by those skilled in the art, and the protection scope of the application can be more clearly and explicitly defined.

[0064] As Figures 8 to 14 shown is a dynamic total temperature probe comb of thin film platinum resistance for measuring transonic unsteady flow field, which is composed of a probe support rod (1), a positioning block (2), a probe head (3), a right thin film platinum resistance (4), a left thin film platinum resistance (5), a circular pipeline (6), and a lead hole (7), and is characterized in that: the probe support rod (1) has the circular pipeline (6) inside, the tail of the probe support rod (1) has the positioning block (2), the probe head (3) is a pyramid with the top surface of the pyramid being provided with the lead hole (7), the number of the probe heads (3) is determined according to the measurement requirement and is at least three, the probe heads (3) are fixed at different spanwise measurement positions of the probe support rod (1) respectively, the lead hole (7) is communicated with the circular pipeline (6), the right thin film platinum resistance (4) and the left thin film platinum resistance (5) are installed above the lead hole (7), and the lead wires of the right thin film platinum resistance (4) and the left thin film platinum resistance (5) are led out from the tail of the probe through the lead hole (6) and the circular pipeline (5);

[0065] The probe support rod (1) is a cylinder, the diameter d of the cylinder is 10 mm, the probe support rod (2) is provided with the circular pipeline (6) inside along the axial direction, the diameter a of the circular pipeline is 6 mm, and the lead wires of the thin film platinum resistance are connected with the external collection equipment through the circular pipeline (6) after passing through the lead hole;

[0066] The length of the top surface of the pyramid of the probe head (3) is 5 mm, the width is 3 mm, the angle between the top surface and the inclined surface of the probe head (3) is 120°, the probe head (3) is made of insulating and heat insulating material, the heat conduction error during measurement is reduced, and the measurement precision and frequency response of the probe are improved;

[0067] The center of the lead hole (7) coincides with the center of the top surface of the pyramid, and the diameter is 0.5 mm;

[0068] The right thin film platinum resistance (4) and the left thin film platinum resistance (5) are installed on the lead hole, the right thin film platinum resistance (4) and the left thin film platinum resistance (5) adopt micro four-wire thin film platinum resistance, the length is 1mm, the width is 0.5mm, the thickness is 0.1mm, four-wire measurement can effectively eliminate the influence of lead resistance on measurement results, improve measurement precision, and guarantee data stability and accuracy;

[0069] The installation distance of the right thin film platinum resistance (4) and the left thin film platinum resistance (5) is x, and the value of x is 0.5mm;

[0070] The cross section of the positioning block (2) is a regular quadrilateral, the center line of the cross section and the center line of the thin film platinum resistance (4) are in the same plane as the axis of the probe support rod (1), the thickness of the positioning block is a, the value of a is 8mm, and the distance between the positioning block (2) and the bottom of the probe support rod (1) is b, the value of b is 20mm;

[0071] The application proposes a data processing method based on a thin film platinum resistance dynamic total temperature probe comb for measuring a transonic unsteady flow field, a wide range calibration is carried out on a thin film platinum resistance dynamic total temperature probe comb for measuring a transonic unsteady flow field in a calibration wind tunnel, the calibration speed range is 1 Mach to 2 Mach with an interval of 0.1 Mach, the deflection angle range is -80° to 80° with an interval of 5°, the pitch angle range is -40° to 40° with an interval of 5°, when the wind tunnel test calibration is carried out, two pieces of thin film platinum resistance are used to simultaneously measure the temperature, the two pieces of thin film platinum resistance are provided with different constant currents by a signal generator, the initial temperatures of the two pieces of resistance are different, but the same convective heat transfer surface heat transfer coefficient h is possessed, so that the heat flux density ratio of the two pieces of thin film platinum resistance under different working conditions can be obtained, the heat flux density ratio is defined as S, and the following equation is satisfied:

[0072] q1=h(T t -T w1 )

[0073] q2=h(T t -T w2 )

[0074]

[0075] In the formula, q1 and q2 are heat flux densities of thin film platinum resistance, unit: W / m 2 ; Tw1 and Tw2 are temperatures measured by thin film platinum resistance, unit: K; Tt is total temperature of a calibration wind tunnel inflow, unit: K, the heat flux density ratio S under different calibration working conditions can be obtained through the above calibration method;

[0076] When the test measurement is carried out, the corresponding heat flux density ratio S can be found from the calibration data under the known inflow working condition, the total temperature T of the measured gas flow can be calculated through the following formula from the measured Tw1 and Tw2 data.g :

[0077]

[0078] The application is based on a dynamic total temperature probe of double thin film platinum resistance, obtains temperature analytical transfer function coefficients through calibration test, constructs a temperature measurement transfer function of the dynamic total temperature probe of double thin film platinum resistance, and reconstructs airflow total temperature of a measured transonic unsteady flow field, so that the frequency response and measurement precision of the dynamic total temperature probe can be greatly improved.

Claims

1. A data processing method for a dynamic total temperature probe comb based on a thin-film platinum resistance thermometer for measuring unsteady flow fields, wherein the probe comb comprises a probe support (1), a positioning block (2), a probe (3), a right thin-film platinum resistance thermometer (4), a left thin-film platinum resistance thermometer (5), a circular tube (6), and a lead hole (7), characterized in that: The probe support rod (1) has a circular pipe (6) inside and a positioning block (2) at the tail. The probe (3) is a cylinder with a frustum head, and there are at least 3 of them. They are fixed at different spanwise measurement positions on the probe support rod (1). The center of the top surface of the frustum of the probe (3) has a lead hole (7) which is connected to the circular pipe (6). A right thin film platinum resistance (4) and a left thin film platinum resistance (5) are installed above the lead hole (7). The leads of the right thin film platinum resistance (4) and the left thin film platinum resistance (5) are led out from the tail of the probe through the lead hole (7) and the circular pipe (6). The probe support rod (1) is a cylinder with a diameter d. The value of d is 2 mm ≤ d ≤ 10 mm. The probe support rod (1) has a circular pipe (6) inside along the axial direction. The diameter of the circular pipe is a. The value of a is 1 mm ≤ a ≤ 8 mm. The thin film platinum resistance wire passes through the lead hole and is connected to the external acquisition equipment through the circular pipe (6). The top surface diameter of the probe (3) is 1 mm to 3 mm, the bottom surface diameter is 3 mm to 6 mm, the cone angle of the probe (3) is 30° to 100°, and the probe (3) is made of insulating and heat-insulating material to reduce the thermal conductivity error during measurement and improve the measurement accuracy and frequency response of the probe. The center of the lead hole (7) coincides with the center of the top surface of the frustum, and the diameter is 0.2 mm to 1 mm; The right thin-film platinum resistance (4) and the left thin-film platinum resistance (5) are mounted on the lead hole. The thin-film platinum resistance (4) adopts a miniature four-wire thin-film platinum resistance with a length of 0.5 mm to 3 mm, a width of 0.1 mm to 1.5 mm, and a thickness of 0.01 mm to 0.2 mm. The four-wire measurement can effectively eliminate the influence of lead resistance on the measurement results, improve the measurement accuracy, and ensure the stability and accuracy of the data. The installation distance between the right thin-film platinum resistance (4) and the left thin-film platinum resistance (5) is x, and the value of x is in the range of 0.2 mm ≤ x ≤ 1 mm; The positioning block (2) has a cross-section of a regular quadrilateral, a regular pentagon, a regular hexagon or a regular heptagon. The center line of the cross-section is in the same plane as the axis of the probe support rod (1). The thickness of the positioning block is a, and the value of a is 2 mm ≤ d ≤ 10 mm. The distance between the positioning block (2) and the bottom of the probe support rod (1) is b, and the value of b is 5 mm ≤ b ≤ 20 mm. In a calibration wind tunnel, the dynamic total temperature probe comb of the thin-film platinum resistance thermometer used for measuring unsteady flow fields is calibrated over a wide range. The calibration speed range is Mach 0.1 to Mach 2, the deflection angle range is -80° to 80°, and the pitch angle range is -40° to 40°. During wind tunnel calibration, temperature measurements are performed simultaneously using two thin-film platinum resistance thermometers. The two thermometers are supplied with different constant currents by a signal generator. The two thermometers have different initial temperatures but the same convective heat transfer surface heat transfer coefficient h. The ratio of the heat flux densities of the two thin-film platinum resistance thermometers under different operating conditions can be obtained. The ratio of heat flux densities is defined as S and satisfies the following equation: q1=h(T t -T w1 ) q2=h(T t -T w2 ) In the formula, q1 and q2 represent the heat flux density of the thin-film platinum resistance thermometer, in W / m³. 2 Tw1, Tw2 — Temperature measured by thin-film platinum resistance thermometer, in K; Tt — Total incoming flow temperature of the calibration wind tunnel, in K. The ratio S of heat flux density under different calibration conditions can be obtained through the above calibration method. During the test measurement, under known incoming flow conditions, the corresponding heat flux density ratio S can be obtained from the calibration data. Using the measured Tw1 and Tw2 data, the total temperature T of the measured airflow can be calculated using the following formula. g : This invention is based on a dynamic total temperature probe using a dual-film platinum resistance thermometer. The temperature analytical transfer function coefficients are obtained through calibration experiments, and the temperature transfer function of the dynamic total temperature probe using the dual-film platinum resistance thermometer is constructed. This reconstructs the total temperature of the airflow in the measured flow field. During measurement, only the incoming flow parameters need to be obtained, without needing to know the physical properties of the measured medium.

Images