A thin-film platinum resistance dynamic total temperature probe for measuring three-dimensional unsteady flow fields

Abstract

The present application belongs to the technical field of dynamic temperature test, and particularly relates to a thin-film platinum resistance dynamic total temperature probe for measuring three-dimensional unsteady flow field, which comprises a probe head, a probe stem, thin-film platinum resistances, lead holes and a circular pipeline. The probe head is a wedge-top double-circular-arc prism structure, the leeward surface of the probe head is a cylindrical back cambered surface, the windward surface comprises a wedge-top inclined surface, a cylindrical front flat surface, a left symmetrical flat surface and a right symmetrical flat surface, the windward surface is provided with four lead holes which are not communicated with each other and are communicated with the circular pipeline, the four thin-film platinum resistances are installed on the lead holes, and the thin-film platinum resistance cables are led out of the probe tail through the corresponding lead holes and the inner circular pipeline of the probe stem. The present application is calibrated in a wind tunnel, compared with the existing temperature probe, can measure the total temperature, static temperature, deflection angle, pitch angle and Mach number of the three-dimensional unsteady flow field changing with time, and provides a high-efficiency and accurate means for measuring the unsteady flow field parameters for impeller experiment.

Description

Technical Field

[0001] This invention belongs to the field of dynamic temperature testing technology, specifically relating to a thin-film platinum resistance dynamic total temperature probe for measuring three-dimensional unsteady flow fields. It is suitable for measuring transient information of three-dimensional unsteady flow fields in turbomachinery. Its core lies in rapidly and accurately measuring and monitoring the changes in transient total temperature, static temperature, deflection angle, pitch angle, and Mach number of the three-dimensional unsteady flow field of turbomachinery. Background Technology

[0002] The three-dimensional flow fields at the inlet, outlet, and interstages of an turbomachinery are inherently unsteady due to fluid viscosity, shock waves, rotor rotation, tip clearance, and the staggered arrangement of moving and stationary blade rows. This makes it extremely difficult to rapidly and accurately obtain the time-varying temperature fields at the inlet, outlet, and interstages. For turbomachinery, researchers prefer to obtain the dynamic temperature distribution and airflow direction angle at the interstages and rotor outlet to validate designs and conduct flow field diagnostics, thereby improving machine performance. Therefore, to rapidly and accurately obtain the transient temperature fields at the inlet, outlet, and interstages of a turbomachinery, more targeted testing methods must be developed.

[0003] Currently, dynamic pressure probes are commonly used to acquire pitch and deflection angle information of the incoming flow. However, due to the influence of the incoming flow temperature on the dynamic pressure sensor, the maximum test incoming flow temperature is limited to no more than 200℃ while ensuring accuracy, which greatly restricts its application range. In contrast, thin-film platinum resistance temperature sensors can be used in environments up to 800℃. For the total flow temperature, thermocouple temperature sensors and hot-wire temperature probes are commonly used to acquire dynamic temperature signals of the flow field. Among them, thermocouple temperature sensors have a low response frequency, and even the fine-wire thermocouple temperature sensors with the highest frequency response cannot fully meet the testing requirements of the transient temperature field at the inlet, outlet, and interstage of the impeller under special operating conditions. Furthermore, compared with thin-film platinum resistance temperature sensors, thermocouples have lower measurement accuracy. During long-term use, thermocouples may experience increased measurement errors due to material aging and hot-spot drift, and are easily affected by environmental factors. Hot-wire temperature probes have extremely short thermal response times, enabling them to rapidly capture transient changes in temperature and flow. Furthermore, their very small size provides high spatial resolution. However, they are typically made of very thin metal wires, resulting in high manufacturing and maintenance costs, susceptibility to breakage and damage, and poor durability, thus increasing testing costs and unreliability. Additionally, thermocouple temperature sensors and hot-wire temperature probes can only measure the total temperature and cannot capture changes in deflection and pitch angles in the transonic three-dimensional unsteady flow field of turbomachinery.

[0004] Therefore, there is an urgent need to develop a rapid, high-precision testing technology that is resistant to airflow erosion, has low spatial resolution, and causes minimal interference to the flow field, in order to quickly and accurately obtain the transient temperatures, pitch angles, and deflection angles of the inlet, outlet, and interstages of the turbomachinery. This technology will enable the precise measurement of dynamic temperatures, deflection angles, and pitch angles of unsteady flow fields under high-temperature environments, providing reliable measurement methods and technical support for the high-performance design and optimization of turbomachinery. Summary of the Invention

[0005] This invention discloses a dynamic total temperature probe for measuring three-dimensional unsteady flow fields using thin-film platinum resistance thermometers. The probe includes a probe head, a probe support, a left, middle, right, and upper thin-film platinum resistance thermometer, a circular pipe, a wedge-shaped inclined surface, a cylindrical front section, a left plane, and a right plane. The probe head is a wedge-shaped prism structure. During measurement, the windward side of the probe head includes the wedge-shaped inclined surface of the wedge-shaped prism, the cylindrical front section, and symmetrical left and right planes. The leeward side is the cylindrical rear arc surface. The cylindrical rear arc surface and the probe support are the side surface of the same cylinder. The axis of the circular pipe coincides with the axis of the probe support. Each of the wedge-shaped inclined surface, the cylindrical front section, the left plane, and the right plane of the probe head has a lead hole. Thin-film platinum resistance thermometers are installed in these lead holes. These four thin-film platinum resistance thermometers are of the same size. The wires of the thin-film platinum resistance thermometers are led out through the corresponding lead holes and connected to an external data acquisition device via the circular pipe.

[0006] During use, the resistance value of the thin-film platinum resistance thermometer changes with temperature, as shown in the following formula:

[0007] R t =R0[1+AT+BT] 2 ]

[0008] Where R0 is the resistance value at 0℃, and A and B are the graduation constants. The probe is placed in the measured flow field. Before the formal test, static calibration is performed on four thin-film platinum resistance thermometers as the temperature of the flow field changes. To achieve higher precision measurements, a standard temperature device and a standard ohmmeter are needed to calibrate the specific platinum resistance thermometer to obtain its characteristic curve, i.e., to obtain the coefficients of each term in the characteristic curve, which are used for resistance-temperature conversion during measurement. The static calibration steps are as follows: connect the thin-film platinum resistance sensor to be calibrated to a high-precision resistance meter and place it in the constant temperature bath of a dry metrology furnace, ensuring that the sensor is centered in the furnace and avoiding contact with the furnace wall. After completing the above installation preparations, turn on the dry metrology furnace, adjust to the calibration point temperature, and wait for at least 30 minutes until the sensor reaches thermal equilibrium (the sensor reading remains unchanged). The calibration temperature point should include 0℃, and temperature calibration should be performed according to the actual temperature measurement range, calibrating every 10℃.

[0009] Measuring the resistance of a thin-film platinum resistance sensor at 0°C and two other temperatures within the measurement range is called the "three-point calibration" method, which yields the following set of equations:

[0010]

[0011] Solving the system of equations simultaneously yields:

[0012]

[0013] Finally, the temperature measurement formula for platinum resistance thermometers within the calibration range is obtained:

[0014]

[0015] After the above static calibration, the calibration constants A and B, as well as the formula for calculating the measured temperature, are obtained through data processing methods.

[0016] After static calibration, a wide-range calibration was performed in the calibration wind tunnel, with a calibration speed range of Mach 0.1 to Mach 1.4, a deflection angle range of -80° to 80°, and a pitch angle range of -40° to 40°. The deflection angle, pitch angle, and total temperature characteristics of a thin-film platinum resistance dynamic total temperature probe for measuring three-dimensional unsteady flow fields were determined.

[0017] Define the deflection angle coefficient:

[0018]

[0019] Define the pitch angle factor:

[0020]

[0021] Define the total temperature coefficient:

[0022]

[0023] Define the static temperature coefficient:

[0024]

[0025] Where yaw is the probe rotation deflection angle, pitch is the probe elevation angle, and T1, T2, T3, and T4 are different airflow deflection angles α and elevation angles. The calibration temperature data for the lower, middle, left, right, and upper thin-film platinum resistance thermometers are given. Tt represents the total incoming flow temperature of the calibration wind tunnel, and Ts represents the static incoming flow temperature of the calibration wind tunnel.

[0026] This invention provides a thin-film platinum resistance dynamic total temperature probe for measuring three-dimensional unsteady flow fields. The technical problems it addresses are: first, the insufficient accuracy of existing dynamic temperature probes; second, the low frequency response of existing dynamic temperature probes due to the limitations of traditional dynamic temperature sensors; and third, the inability of existing dynamic temperature probes to measure deflection angle, pitch angle, static temperature, and Mach number.

[0027] The technical solution of this invention is:

[0028] 1. A dynamic total temperature probe for measuring a three-dimensional unsteady flow field using a thin-film platinum resistance thermometer, comprising a probe head (1), a probe support (2), a left thin-film platinum resistance thermometer (3), a middle thin-film platinum resistance thermometer (4), a right thin-film platinum resistance thermometer (5), an upper thin-film platinum resistance thermometer (6), a circular pipe (7), a wedge-shaped inclined surface (8), a cylindrical front tangent (9), a left side plane (10), and a right side plane (11), characterized in that: the probe head (1) is a wedge-shaped prism structure, and the windward surface of the probe head (1) during measurement includes the wedge-shaped inclined surface (8), the cylindrical front tangent (9), the symmetrical left side plane (10), and the right side plane (11). The leeward side is the rear arc surface of a cylinder; the rear arc surface of the cylinder and the probe support rod (2) are the side of the same cylinder, and the axis of the circular pipe (7) coincides with the axis of the probe support rod (2); a lead hole is opened on the wedge-shaped inclined surface (8), the front tangent surface (9), the left side (10), and the right side (11) of the probe head (1), and a thin film platinum resistance is installed on the lead hole respectively, namely the left thin film platinum resistance (3), the middle thin film platinum resistance (4), the right thin film platinum resistance (5), and the upper thin film platinum resistance (6). These four thin film platinum resistances are the same size, and the wires of the thin film platinum resistance are led out through the corresponding lead hole and the circular pipe (7) to connect with the external acquisition equipment.

[0029] 2. The probe support rod (2) is a cylinder with a diameter d. The value of d is 2 mm ≤ d ≤ 10 mm. The probe support rod (2) has a circular pipe (7) 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 (7).

[0030] 3. The angle between the wedge-shaped inclined surface (8) of the probe head (1) and the axis of the probe support rod (2) is 36° to 54°.

[0031] 4. The center line of the upper thin film platinum resistance (6), the center line of the middle thin film platinum resistance (4) and the axis of the probe support (2) are on the same plane. The left plane (10) and the right plane (11) are symmetrically distributed along the plane. The angle between the left plane (5) and the right plane (6) is 30° to 70°.

[0032] 5. The left thin-film platinum resistor (3) and the right thin-film platinum resistor (5) on the probe head (1) are symmetrically distributed along the plane containing the center line of the middle thin-film platinum resistor (4) and the upper thin-film platinum resistor (6).

[0033] 6. The distance between the center of the upper thin-film platinum resistance (6) on the probe head (1) and the lowest point of the wedge apex slope (8) is 1 mm to 5 mm.

[0034] 7. The distance between the center of the thin-film platinum resistance (4) on the probe head (1) and the lowest point of the arc of the wedge top slope (3) is 1 mm to 3 mm.

[0035] 8. The left thin-film platinum resistance (3), the middle thin-film platinum resistance (4), the right thin-film platinum resistance (5), and the upper thin-film platinum resistance (6) are respectively installed on the lead hole. The left thin-film platinum resistance (3), the middle thin-film platinum resistance (4), the right thin-film platinum resistance (5), and the upper thin-film platinum resistance (6) are made of the same material and size. The left thin-film platinum resistance (3), the middle thin-film platinum resistance (4), the right thin-film platinum resistance (5), and the upper thin-film platinum resistance (6) are all miniature four-wire thin-film platinum resistances with a length of 1 mm to 3 mm, a width of 0.5 mm to 1.5 mm, and a thickness of 0.05 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.

[0036] 9. Probe head (1) The arc diameter of the wedge-shaped prism structure is 4 mm to 10 mm, and the height of the prism structure is 15 mm to 50 mm.

[0037] This invention provides a thin-film platinum resistance dynamic total temperature probe for measuring three-dimensional unsteady flow fields, which has the following advantages:

[0038] Beneficial effect 1: After calibration in a wind tunnel, this invention can obtain transient total temperature, static temperature, deflection angle, pitch angle and Mach number information of the incoming flow according to its unique data processing method.

[0039] Benefit 2: After calibration in a wind tunnel and constant temperature furnace, this invention improves measurement accuracy. The use of insulating material on the substrate enhances the probe's frequency response, enabling precise capture of rapidly changing temperature fields. This provides an efficient and accurate method for testing unsteady flow fields in turbomachinery.

[0040] Benefit 3: The probe of this invention has a built-in positioning function, and the vertical cross-section of the head forms a positioning reference. The probe is easy and simple to install, does not require rotation during measurement, does not have periodic requirements for the measured flow field, and has a wide range of applications.

[0041] Benefit 4: The probe head structure of this invention is simple and compact, in the shape of an "I", with a small size. The dual thin-film platinum resistance is arranged vertically, which improves the spatial resolution of the probe and is suitable for measurement of the inlet, outlet and interstage of impellers.

[0042] Benefit 5: The thin-film platinum resistance thermometer of the present invention is small in size and is a four-wire platinum resistance thermometer, which has high measurement accuracy. The sensing part is not affected by the structure of the probe itself, and it senses the pulsation of the incoming flow first. The flow field information is not distorted, and the measurement accuracy is high. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the structure of a thin-film platinum resistance dynamic total temperature probe for measuring a three-dimensional unsteady flow field in an embodiment of the present invention.

[0044] Figure 2 yes Figure 1 Top view.

[0045] Figure 3 yes Figure 1 Sectional view along direction A.

[0046] Figure 4 yes Figure 1 Side view.

[0047] Figure 5 yes Figure 1 Sectional view along direction B.

[0048] Figure 6 yes Figure 5 A magnified view of a portion of the image.

[0049] Wherein: 1-Probe head, 2-Probe support, 3-Left thin film platinum resistance, 4-Middle thin film platinum resistance, 5-Right thin film platinum resistance, 6-Upper thin film platinum resistance, 7-Circular tube, 8-Wedge top slope, 9-Cylindrical front slab, 10-Left side plane, 11-Right side plane. Detailed Implementation

[0050] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more explicit definition of the scope of protection of the present invention.

[0051] like Figures 1-6The image shows a dynamic total temperature probe for measuring a three-dimensional unsteady flow field using a thin-film platinum resistance thermometer. It comprises a probe head (1), a probe support (2), a left thin-film platinum resistance thermometer (3), a middle thin-film platinum resistance thermometer (4), a right thin-film platinum resistance thermometer (5), an upper thin-film platinum resistance thermometer (6), a circular pipe (7), a wedge-shaped inclined surface (8), a cylindrical front tangent (9), a left side plane (10), and a right side plane (11). The probe head (1) is a wedge-shaped prism structure. During measurement, the windward surface of the probe head (1) includes the wedge-shaped inclined surface (8), the cylindrical front tangent (9), the symmetrical left side plane (10), and the right side plane (11). The leeward side is the cylindrical rear arc surface; the cylindrical rear arc surface and the probe support rod (2) are the side of the same cylinder, and the axis of the circular pipe (7) coincides with the axis of the probe support rod (2); a lead hole is opened on the wedge top slope (8), the cylindrical front tangent (9), the left side (10), and the right side (11) of the probe head (1), and a thin film platinum resistance is installed on the lead hole respectively, namely the left thin film platinum resistance (3), the middle thin film platinum resistance (4), the right thin film platinum resistance (5), and the upper thin film platinum resistance (6). These four thin film platinum resistances are the same size, and the wires of the thin film platinum resistance are led out through the corresponding lead hole and the circular pipe (7) to connect with the external acquisition equipment;

[0052] The probe support rod (2) is a cylinder with a diameter d of 10 mm. The probe support rod (2) has a circular pipe (7) with a diameter of 5 mm. The thin film platinum resistance wire passes through the lead hole and is connected to the external acquisition equipment through the circular pipe (7).

[0053] The angle between the wedge-shaped inclined surface (8) of the probe head (1) and the axis of the probe support rod (2) is 40°;

[0054] The center line of the upper thin-film platinum resistance (6), the center line of the middle thin-film platinum resistance (4), and the axis of the probe support (2) are on the same plane. The left plane (10) and the right plane (11) are symmetrically distributed along this plane. The angle between the left plane (5) and the right plane (6) is 40°.

[0055] The left thin-film platinum resistor (3) and the right thin-film platinum resistor (5) on the probe head (1) are symmetrically distributed along the plane containing the center line of the middle thin-film platinum resistor (4) and the upper thin-film platinum resistor (6);

[0056] The distance between the center of the upper thin-film platinum resistance (6) on the probe head (1) and the lowest point of the wedge apex slope (8) is 2 mm;

[0057] The distance between the center of the thin-film platinum resistance (4) on the probe head (1) and the lowest point of the arc of the wedge apex slope (3) is 2 mm;

[0058] The left thin-film platinum resistance (3), the middle thin-film platinum resistance (4), the right thin-film platinum resistance (5), and the upper thin-film platinum resistance (6) are respectively mounted on the lead hole. The left thin-film platinum resistance (3), the middle thin-film platinum resistance (4), the right thin-film platinum resistance (5), and the upper thin-film platinum resistance (6) are made of the same material and size. The left thin-film platinum resistance (3), the middle thin-film platinum resistance (4), the right thin-film platinum resistance (5), and the upper thin-film platinum resistance (6) are all made of miniature four-wire thin-film platinum resistance with a length of 1 mm, a width of 0.5 mm, and a thickness of 0.1 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.

[0059] The diameter of the arc of the wedge-shaped prism structure of the probe head (1) is 10 mm, and the height of the prism structure is 30 mm.

[0060] This invention presents a dynamic total temperature probe for measuring a high-subsonance three-dimensional unsteady flow field using a four-film platinum resistance thermometer. First, the probe is calibrated. As the temperature changes, the resistance value of the film platinum resistance thermometer also changes, as shown in the following formula:

[0061] R t =R0[1+AT+BT] 2 ]

[0062] Where R0 is the resistance value at 0℃, and A and B are the graduation constants. The probe is placed in the measured flow field. Before the formal test, static calibration is performed on four thin-film platinum resistance thermometers as the temperature of the flow field changes. To achieve higher precision measurements, a standard temperature device and a standard ohmmeter are needed to calibrate the specific platinum resistance thermometer to obtain its characteristic curve, i.e., to obtain the coefficients of each term in the characteristic curve, which are used for resistance-temperature conversion during measurement. The static calibration steps are as follows: connect the thin-film platinum resistance sensor to be calibrated to a high-precision resistance meter and place it in the constant temperature bath of a dry metrology furnace, ensuring that the sensor is centered in the furnace and avoiding contact with the furnace wall. After completing the above installation preparations, turn on the dry metrology furnace, adjust to the calibration point temperature, and wait for at least 30 minutes until the sensor reaches thermal equilibrium (the sensor reading remains unchanged). The calibration temperature point should include 0℃, and temperature calibration should be performed according to the actual temperature measurement range, calibrating every 10℃.

[0063] Measuring the resistance of a thin-film platinum resistance sensor at 0°C and two other temperatures within the measurement range is called the "three-point calibration" method, which yields the following set of equations:

[0064]

[0065] Solving the system of equations simultaneously yields:

[0066]

[0067] Finally, the temperature measurement formula for platinum resistance thermometers within the calibration range is obtained:

[0068]

[0069] After the above static calibration, the calibration constants A and B, as well as the formula for calculating the measured temperature, are obtained through data processing methods.

[0070] After static calibration, a wide-range calibration was performed in the calibration wind tunnel. The calibration speed range was from Mach 0.1 to Mach 1.4, with an interval of Mach 0.1; the deflection angle range was from -80° to 80°; and the pitch angle range was from -40° to 40°, with an interval of 5°. The deflection angle, pitch angle, total temperature, and static temperature characteristics of a four-film platinum resistance dynamic total temperature probe for measuring high subsonic three-dimensional unsteady flow fields were determined.

[0071] Define the deflection angle coefficient:

[0072]

[0073] Define the pitch angle factor:

[0074]

[0075] Define the total temperature coefficient:

[0076]

[0077] Define the static temperature coefficient:

[0078]

[0079] Where yaw is the probe rotation deflection angle, pitch is the probe elevation angle, and T1, T2, T3, and T4 are different airflow deflection angles α and elevation angles. The calibration temperature data for the lower, middle, left, right, and upper thin-film platinum resistance thermometers, where Tt is the total incoming temperature of the calibration wind tunnel and Ts is the static incoming temperature of the calibration wind tunnel.

[0080] According to the above definition, the calibration curves of deflection angle coefficient-pitch angle coefficient, deflection angle-deflection angle coefficient, pitch angle-pitch angle coefficient, deflection angle-total temperature coefficient, pitch angle-total temperature coefficient, deflection angle-static temperature coefficient, and pitch angle-static temperature coefficient are calculated for each incoming Mach number at different deflection angles and pitch angles.

[0081] During measurement, the deflection angle coefficient and pitch angle coefficient are calculated by simultaneously measuring the unsteady temperature data sensed by four thin-film platinum resistance thermometers. The deflection angle and pitch angle are calculated using a calibration grid. Then, the total temperature coefficient is obtained by interpolation on the calibration curve of deflection angle-total temperature coefficient or pitch angle-total temperature coefficient, and then the total temperature is calculated. Then, the static temperature coefficient is obtained by interpolation on the calibration curve of deflection angle-static temperature coefficient or pitch angle-static temperature coefficient, and then the static temperature is calculated. Finally, the flow Mach number is derived from the total temperature and static temperature.

Claims

1. A dynamic total temperature probe for measuring a three-dimensional unsteady flow field using a thin-film platinum resistance thermometer, comprising a probe head (1), a probe support (2), a left thin-film platinum resistance thermometer (3), a middle thin-film platinum resistance thermometer (4), a right thin-film platinum resistance thermometer (5), an upper thin-film platinum resistance thermometer (6), a circular pipe (7), a wedge-shaped inclined surface (8), a cylindrical front tangent surface (9), a left side plane (10), and a right side plane (11), characterized in that: The probe head (1) is a wedge-shaped prism structure. The windward side of the probe head (1) during probe measurement includes the wedge-shaped inclined surface (8), the cylindrical front tangent (9), the symmetrical left side plane (10) and the right side plane (11) of the wedge-shaped prism, and the leeward side is the cylindrical rear arc surface. The cylindrical rear arc surface and the probe support rod (2) are the side of the same cylinder, and the axis of the circular pipe (7) coincides with the axis of the probe support rod (2). There is a lead hole on each of the wedge-shaped inclined surface (8), the cylindrical front tangent (9), the left side plane (10), and the right side plane (11) of the probe head (1). Thin film platinum resistance is installed on the lead hole, namely the left thin film platinum resistance (3), the middle thin film platinum resistance (4), the right thin film platinum resistance (5), and the upper thin film platinum resistance (6). These four thin film platinum resistances are the same size. The wires of the thin film platinum resistance are led out through the corresponding lead hole and the circular pipe (7) to connect with the external acquisition equipment. The probe support rod (2) is a cylinder with a diameter d. The value of d is 2 mm ≤ d ≤ 10 mm. The probe support rod (2) has a circular pipe (7) 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 (7). The angle between the wedge-shaped inclined surface (8) of the probe head (1) and the axis of the probe support rod (2) is 36° to 54°. The probe head is made of heat-insulating material to reduce the heat conduction between the sensing part and the substrate during the measurement of the thin film platinum resistance and improve the dynamic response of the total temperature probe of the thin film platinum resistance. The center line of the upper thin film platinum resistance (6), the center line of the middle thin film platinum resistance (4) and the axis of the probe support (2) are on the same plane. The left plane (10) and the right plane (11) are symmetrically distributed along the plane. The angle between the left plane (10) and the right plane (11) is 30° to 70°. The left thin-film platinum resistor (3) and the right thin-film platinum resistor (5) on the probe head (1) are symmetrically distributed along the plane containing the center line of the middle thin-film platinum resistor (4) and the upper thin-film platinum resistor (6); The distance between the center of the upper thin-film platinum resistance (6) on the probe head (1) and the lowest point of the wedge-shaped inclined surface (8) is 1 mm to 5 mm; The distance between the center of the thin-film platinum resistance (4) on the probe head (1) and the lowest point of the arc of the wedge top slope (8) is 1 mm to 3 mm; The left thin-film platinum resistance (3), the middle thin-film platinum resistance (4), the right thin-film platinum resistance (5), and the upper thin-film platinum resistance (6) are respectively installed on the lead hole. The left thin-film platinum resistance (3), the middle thin-film platinum resistance (4), the right thin-film platinum resistance (5), and the upper thin-film platinum resistance (6) are made of the same material and size. The left thin-film platinum resistance (3), the middle thin-film platinum resistance (4), the right thin-film platinum resistance (5), and the upper thin-film platinum resistance (6) are all miniature four-wire thin-film platinum resistances 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 diameter of the arc of the wedge-shaped prism structure of the probe head (1) is 4 mm to 10 mm, and the height of the prism structure is 15 mm to 50 mm. A data processing method is proposed based on a dynamic total temperature probe for measuring three-dimensional unsteady flow fields using a thin-film platinum resistance thermometer. The method involves wide-range calibration of the probe in a calibration wind tunnel, with calibration speeds ranging from Mach 0.1 to Mach 1.4, deflection angles from -80° to 80°, and pitch angles from -40° to 40°. Using this data processing method, calibration curves are obtained for different deflection angle coefficients at each Mach number, including those for pitch angle coefficient, deflection angle-total temperature coefficient, pitch angle-total temperature coefficient, and pitch angle-static temperature coefficient. The method described is as follows: Define the deflection angle coefficient: Define the pitch angle factor: Define the total temperature coefficient: Define the static temperature coefficient: Among them, T1, T2, T3, and T4 are the calibration temperature data of the middle, left, right, and upper thin-film platinum resistance thermometers under different airflow deflection angles α and pitch angles φ, Tt is the total temperature of the incoming flow to the calibration wind tunnel, and Ts is the static temperature of the incoming flow to the calibration wind tunnel. According to the above definition, the calibration curves of deflection angle coefficient-pitch angle coefficient, deflection angle-deflection angle coefficient, pitch angle-pitch angle coefficient, deflection angle-total temperature coefficient, pitch angle-total temperature coefficient, deflection angle-static temperature coefficient, and pitch angle-static temperature coefficient are calculated for each incoming Mach number at different deflection angles and pitch angles. In actual measurements, the deflection angle coefficient and pitch angle coefficient are calculated from the temperature data measured by each thin-film platinum resistance thermometer. The deflection angle and pitch angle are then calculated using the calibration curve. The total temperature coefficient is then calculated by interpolation on the deflection angle-total temperature coefficient or pitch angle-total temperature coefficient calibration curve. The total temperature is then calculated by back-calculating using the definition of the total temperature coefficient. Similarly, the static temperature coefficient is calculated by interpolation on the deflection angle-static temperature coefficient or pitch angle-static temperature coefficient calibration curve. The static temperature is then calculated by back-calculating using the definition of the static temperature coefficient. Finally, the incoming flow Mach number is calculated from the obtained total airflow temperature and static temperature.

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