A probe for measuring all parameters of subsonic three-dimensional steady flow field

Abstract

The present invention belongs to the field of flow field testing technology, and specifically relates to a probe for measuring all parameters of a subsonic three-dimensional steady-state flow field, including a probe head, a temperature sensor, a convection heat exchange groove, an insulating seal, five pressure measuring holes, a pressure pipe channel, a probe support rod, a pressure pipe and a temperature sensor cable. The probe head is cylindrical, and the top of the cylinder has a concave ball socket structure perpendicular to the center line of the cylinder. The inner wall of the ball socket is provided with a pressure measuring middle hole, a pressure measuring upper hole, a pressure measuring lower hole, a pressure measuring left hole and a pressure measuring right hole that are not connected to each other, and a cross-shaped convection heat exchange groove is provided on the back of the ball socket. The temperature sensor is placed in the convection heat exchange groove and faces the center line of the pressure measuring middle hole. The probe of the present invention can simultaneously measure the total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, pitch angle, speed, density and other parameters of a subsonic three-dimensional steady-state flow field, and has the characteristics of small size, long life, wide airflow insensitive angle, high reliability, high spatial resolution and high measurement accuracy.

Description

Technical Field

[0001] The present invention belongs to the technical field of flow field testing, and specifically relates to a probe for measuring all parameters of a subsonic three-dimensional steady-state flow field, which is suitable for measuring all parameters of a subsonic three-dimensional steady-state flow field at an inlet, an inlet, an outlet and an impeller stage of a fan, a compressor and the like in a subsonic inlet machine. Background Art

[0002] For the subsonic three-dimensional steady flow field at the inlet, outlet and impeller stages of fans, compressors and other impellers in turbomachinery, the flow field is chaotic and exhibits a strong three-dimensional nature due to the rotation of the rotor, the staggered arrangement of the moving and static blade rows, the interaction between the mainstream and the tip leakage flow, and the mutual mixing of the mainstream and the wake. There are still many problems in accurately measuring the complex three-dimensional flow field parameters using existing testing technologies and measurement methods.

[0003] In the existing probe test technology, the following two methods are usually used to measure the parameters of complex three-dimensional flow fields: one is to use a pressure probe to obtain parameters such as pressure, Mach number and flow direction of the flow field, and to use a temperature probe to measure the temperature in the flow field. On the one hand, it is impossible to simultaneously obtain the flow parameters in the flow field by using a pressure probe and a temperature probe for measurement. Therefore, in actual measurement, not only will the measurement time and cost increase, but also the position error of the flow field change and the displacement mechanism movement during the two measurements will affect the accuracy of the test measurement; on the other hand, in order to simultaneously obtain all the three-dimensional steady-state flow field parameters, it is inevitable to use multiple probes for testing, which will not only increase the interference of the probe on the flow field flow, but also increase the complexity of the test. At the same time, since the measured flow parameters cannot be guaranteed to come from the same streamline, additional test errors are brought about, which reduces the accuracy of the measurement results. The other is to use a temperature and pressure combined probe for measurement. The traditional temperature and pressure combined probe arranges the temperature sensor and the pressure sensing hole at the same time on the windward side of the probe facing the incoming flow, which requires a relatively large space on the probe surface, resulting in poor spatial resolution of the flow field measurement.

[0004] According to the existing total temperature test technology, the key to whether the temperature probe can accurately measure the total temperature of the airflow is whether the airflow can be stagnant at the temperature measurement point. Therefore, most of the temperature probes are designed according to the temperature sensor facing the mainstream direction. The conventional stagnation structure for measuring the total temperature of the fluid mostly adopts a stagnation cover structure, and the temperature sensor is placed in the stagnation cover. The disadvantages of this design are: first, the temperature sensor is directly washed by the fluid, and is easily affected by oil droplets, dust, etc. mixed in the airflow, and is easy to be damaged, and it will also affect the accuracy of temperature measurement; second, the strength of the temperature sensor is usually improved by increasing its size, and coupled with the size of the stagnation cover, the probe size is large, which cannot meet the temperature measurement requirements of the narrow space such as the compressor blades and turbine blades in the impeller machinery, and its spatial resolution is also poor; third, the airflow insensitive angle is small, when the deflection angle or pitch angle of the incoming flow to be measured is large, the airflow cannot be fully stagnant; at the same time, the heat exchange on the surface of the temperature sensor is insufficient, affecting the accuracy of the total temperature measurement.

[0005] All of the above test problems restrict researchers from conducting in-depth research on the flow field inside the turbomachinery, especially if the data obtained by the pressure probe and the temperature probe are processed separately, then additional errors will be introduced when the speed and other parameters are calculated in combination; and the temperature sensors of the existing temperature-pressure combination probes are all located on the windward side of the probe head facing the mainstream, which has the disadvantages of the above temperature probes and is difficult to meet the requirements for spatial resolution in the measurement. It is not suitable for the accurate measurement of all parameters of the subsonic three-dimensional steady-state flow field, and researchers hope to accurately obtain all parameter information in the flow field at the same time. Therefore, there is an urgent need for a probe for measuring all parameters of the subsonic three-dimensional steady-state flow field, which can be used for the measurement of all parameters of the subsonic three-dimensional steady-state flow field at the inlet, outlet and impeller stage of the fan, compressor and other in the turbomachinery. Summary of the invention

[0006] The existing probes are unable to simultaneously measure the total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, pitch angle, speed and density parameters of the subsonic three-dimensional steady flow field; and the existing temperature probes are large in size, poor in spatial resolution, small insensitive angle of airflow, and the temperature sensors are easily damaged, have short lifespan, low reliability and low measurement accuracy.

[0007] The present invention proposes a probe for measuring all parameters of a subsonic three-dimensional steady-state flow field. The probe head is cylindrical, and an inwardly concave ball-and-socket structure is arranged on the top of the cylinder perpendicular to the center line of the cylinder. The center line of the ball-and-socket is perpendicular to and intersects with the center line of the cylinder. A pressure measuring middle hole is arranged at the place where the ball-and-socket is facing the mainstream direction, and mutually unconnected pressure measuring upper holes, lower holes, left holes and right holes are evenly arranged on the side walls of the ball-and-socket. The measurement of three-dimensional flow field parameters can be realized in combination with the pressure measuring middle hole. In addition, the present invention abandons the design concept of the traditional total temperature probe. Based on the applicant's many years of research, it creatively proposes a layout and structural design that places the temperature sensor on the leeward side of the probe head facing away from the ball socket, and opens a cross convection heat exchange groove on the leeward side of the probe head. The temperature sensor is placed in the cross convection heat exchange groove directly opposite the center line of the pressure measuring hole, which effectively reduces the impact of the airflow on the temperature sensor and the impact of dust and oil droplets mixed in the airflow on the temperature sensor, greatly improving the life of the temperature sensor; effectively reducing the size of the probe head and improving the spatial resolution; strengthening the convection heat exchange between the airflow and the temperature sensor, and the temperature recovery coefficient is high and stable within a larger deflection angle range. Most importantly, the present invention can simultaneously measure the total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, pitch angle, velocity and density parameters of the subsonic three-dimensional steady-state flow field, making up for the shortcomings of the traditional three-dimensional steady-state flow field measurement method.

[0008] The technical solution provided by the present invention is:

[0009] 1. A probe for measuring all parameters of a subsonic three-dimensional steady-state flow field, comprising a probe head (1), a temperature sensor (2), a convection heat exchange groove (3), a heat-insulating seal (4), a temperature sensor cable lead-out channel (5), a pressure measuring middle hole (6), a pressure measuring lower hole (7), a pressure measuring upper hole (8), a pressure measuring right hole (9), a pressure measuring left hole (10), a pressure lead pipe channel (11), a probe support rod (12), a pressure lead pipe (13) and a temperature sensor cable (14), characterized in that: the probe head (1) is cylindrical, and the circular A concave ball-and-socket structure is arranged at the top of the column perpendicular to the center line of the column. The center line of the ball-and-socket is perpendicular to and intersects with the center line of the column. A middle pressure measuring hole (6) is arranged at the position of the ball-and-socket facing the mainstream direction. A lower pressure measuring hole (7), an upper pressure measuring hole (8), a right pressure measuring hole (9), and a left pressure measuring hole (10) which are not connected to each other are evenly arranged on the side wall of the ball-and-socket. A cross-shaped convection heat exchange groove (3) is arranged on the leeward side of the probe head (1) facing away from the ball-and-socket. Different positions of the groove can be used for both air intake and air discharge, so as to achieve self-adaptation with the incoming flow direction and strengthen the flow of air in the groove.

[0010] 2. Furthermore, the diameter of the cylindrical probe head (1) is 2 to 8 mm, and the length is 5 to 45 mm. Five mutually unconnected circular pressure-conducting pipe channels (11) and a circular temperature sensor cable lead-out channel (5) are provided along the axial direction of the probe. The five circular pressure-conducting pipe channels (11) are respectively connected to the pressure measuring middle hole (6), the pressure measuring lower hole (7), the pressure measuring upper hole (8), the pressure measuring right hole (9), and the pressure measuring left hole (10) in the ball socket of the probe head (1), and are respectively connected to five pressure-conducting pipes (13) encapsulated at the connection between the probe head (1) and the probe support rod (12). The pressure-conducting pipe (13) is led out of the tail of the probe support rod (12) through the pressure-conducting pipe channel (11) in the probe support rod (12).

[0011] 3. Furthermore, the diameter of the concave socket structure arranged perpendicular to the center line of the cylinder of the probe head (1) is 1 to 6 mm, the distance between the center of the ball and the side surface of the cylinder of the probe head (1) is 0 to 1 / 6 times the diameter of the socket, the height of the center line of the socket from the end face of the probe head is 0.5 to 4 mm, the pressure measuring middle hole (6), the pressure measuring lower hole (7), the pressure measuring upper hole (8), the pressure measuring right hole (9) and the pressure measuring left hole (10) are all circular and have the same diameter of 0.1 to 1.5 mm, the center line of the pressure measuring middle hole (6) coincides with the center line of the socket, the pressure measuring lower hole (7), the pressure measuring upper hole (8), the pressure measuring right hole (9) and the pressure measuring left hole (10) are located at the same axial position of the center line of the socket and are evenly distributed around the socket, and their center lines are perpendicular to the side wall of the socket and form an angle of 20° to 80° with the center line of the pressure measuring middle hole.

[0012] 4. Furthermore, the convection heat exchange grooves (3) are rectangular with the same width and the centers overlap, the width is 1 to 3 mm, the length of the groove parallel to the center line of the cylinder of the probe head (1) is 0.8 to 6 mm, the depth of the groove perpendicular to the center line is to the position of the temperature sensor (2) head, the diameter of the circular channel where the temperature sensor (2) head is located is 0.8 to 3.5 mm, the axial length of the circular channel is 1 to 7 mm, the axis of the circular channel coincides with the axis of the temperature sensor cable lead-out channel (5), the center axis of the temperature sensor cable lead-out channel (5) is 0.5 to 3 mm away from the center line of the column, and the center axis of the temperature sensor cable lead-out channel (5), the center line of the column and the center line of the pressure measuring hole (6) are on the same plane, and the temperature sensor (2) head is located at the same position. At the intersection of the axis of the circular temperature sensor cable lead-out channel (5) and the center line of the pressure measuring hole (6), and facing the rectangular center of the convection heat exchange groove (3), the temperature sensor (2) is fixed by a heat-insulating seal (4), and the heat-insulating seal (4) plays the role of heat insulation, insulation, sealing and fixing. When the heat-insulating seal (4) and the temperature sensor (2) are installed, the temperature sensor (2) and the heat-insulating seal (4) are first installed and fixed on the circular channel, and the temperature sensor cable (14) is led out of the tail of the probe support rod (12) through the temperature sensor cable lead-out channel (5) in the probe, and then the opening on the end face of the probe head (1) is covered and welded to seal, and the cylindrical axis of the probe head (1) coincides with the cylindrical axis of the probe support rod (12).

[0013] 5. Further, the probe is calibrated through a calibration wind tunnel to obtain a probe calibration curve. In actual measurement, based on the data measured by the five pressure measuring holes and the temperature sensor (2), and according to the calibration coefficient curve and formula obtained by the calibration wind tunnel, through data processing, the total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, pitch angle, speed, and density parameters of the measured three-dimensional steady-state flow field can be obtained simultaneously, thereby increasing the life of the temperature sensor (2) and the airflow insensitive angle range, and improving the measurement space resolution and measurement accuracy.

[0014] The beneficial effects of the present invention are:

[0015] Compared with the existing subsonic three-dimensional steady flow field probe, the probe for measuring all parameters of the subsonic three-dimensional steady flow field of the present invention can achieve the following beneficial effects after being calibrated in a calibrated wind tunnel:

[0016] Beneficial effect 1: Traditional five-hole pressure probes and total temperature probes can only measure pressure or temperature separately. The present invention can simultaneously measure the total temperature, static temperature, total pressure, static pressure, deflection angle, pitch angle, Mach number, density and speed parameters of the subsonic three-dimensional steady-state flow field, effectively reducing the interference to the measured flow field, improving the test accuracy, simplifying the test operation and reducing the test cost.

[0017] Beneficial effect 2: Traditional temperature probes and temperature-pressure combined probes place the temperature sensor directly against the incoming flow, and rely on the incoming flow to stop on the temperature sensor to measure the temperature. The airflow directly impacts the temperature sensor, which is very easy to damage the temperature sensor, and the measurement insensitive angle is narrow. The present invention creatively places the temperature sensor on the leeward side of the probe head. This design not only increases the range of the total temperature insensitive angle, but also avoids the incoming flow from directly impacting the temperature sensor and reduces the impact of impurities such as dust and oil droplets in the incoming flow on the temperature sensor, ensuring the measurement accuracy and effectively improving the service life of the temperature sensor.

[0018] Beneficial effect three: The traditional temperature and pressure combination probe places the temperature sensor and the pressure sensing hole adjacent to each other on the windward side of the probe head, which increases the size of the probe head, which not only greatly interferes with the flow field and makes installation difficult, but also reduces the spatial resolution. The present invention places the five pressure sensing holes in the concave spherical socket on the windward side of the probe head, and places the temperature sensor on the leeward side of the probe head facing away from the pressure sensing holes, which not only realizes the simultaneous measurement of multiple parameters on the same streamline, ensuring that the measurement has a sufficiently high spatial resolution, but also makes the best use of the space of the probe head, reducing the size of the probe head.

[0019] Beneficial effect 4: Traditional total temperature measurement requires the addition of an additional stagnation hood, which inevitably causes insufficient heat exchange on the surface of the temperature sensor during measurement, affecting the accuracy of total temperature measurement. The present invention utilizes the vortex flow structure in the separation zone on the leeward side of the probe head to effectively enhance the heat exchange between the airflow and the temperature sensor. At the same time, a cross-shaped convection heat exchange groove is opened on the back. Due to the influence of pressure distribution, different positions of the groove can both inlet and outlet air, achieving self-adaptation with the incoming flow direction and enhancing the flow of air in the groove. Therefore, the temperature recovery coefficient is high and stable within a larger deflection angle and pitch angle range during measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the structure of a probe for measuring all parameters of a subsonic three-dimensional steady-state flow field in Embodiment 1 of the present invention.

[0021] Figure 2 yes Figure 1 Top view of the .

[0022] Figure 3 yes Figure 1 Left view of .

[0023] Figure 4 yes Figure 1 B view.

[0024] Among them: 1-probe head, 2-temperature sensor, 3-convection heat exchange groove, 4-insulating seal, 5-temperature measurement channel, 6-pressure measurement middle hole, 7-pressure measurement lower hole, 8-pressure measurement upper hole, 9-pressure measurement right hole, 10-pressure measurement left hole, 11-pressure pipe channel, 12-probe support rod, 13-pressure pipe, 14-temperature measurement lead.

[0025] Figure 5 It is a schematic diagram of the probe in the first embodiment of the present invention being used to measure the three-dimensional flow field in the air inlet duct.

[0026] Wherein: 1-intake duct wall, 2-probe of the present invention.

[0027] Figure 6 It is a schematic diagram of the probe used in the second embodiment of the present invention to measure the three-dimensional flow field between compressor stages.

[0028] Among them: 1-casing wall, 2-hub wall, 3-first stage stator, 4-second stage rotor, 5-probe of the present invention, 6-second stage stator.

[0029] Figure 7 It is a schematic diagram of the structure of a probe for measuring all parameters of a subsonic three-dimensional steady-state flow field in the second embodiment of the present invention.

[0030] Figure 8 yes Figure 7 Left view of .

[0031] Fig. 9 yes Figure 7 Top view of the .

[0032] Among them: 1-probe head, 2-temperature sensor, 3-convection heat exchange groove, 4-insulation seal, 5-temperature measurement channel, 6-pressure measurement middle hole, 7-pressure measurement lower hole, 8-pressure measurement upper hole, 9-pressure measurement right hole, 10-pressure measurement left hole, 11-pressure pipe channel, 12-probe support rod, 13-pressure pipe, 14-temperature measurement lead. DETAILED DESCRIPTION

[0033] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings 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 definite definition of the protection scope of the present invention.

[0034] Embodiment 1:

[0035] For the air intake of an aircraft engine, the flow channel is long, the boundary layer is thick, and the incoming flow is relatively uniform. However, due to the high speed in the air intake channel, impurities such as dust and rainwater may be contained. The probe head (1) and the support rod (12) are selected with a larger diameter to ensure strength and rigidity; the pressure sensing holes (6, 7, 8, 9, 10) can be selected with a larger diameter to prevent contamination by impurities such as dust and rainwater; the temperature sensor can use an armored thermocouple to ensure life, so the following implementation case can be used:

[0036] like Figures 1 to 4 The figure shows a probe for measuring all parameters of a subsonic three-dimensional steady-state flow field according to the present invention. Figure 5 The present invention is a schematic diagram of the probe used to measure the three-dimensional flow field of the engine intake duct. A probe for measuring all parameters of a subsonic three-dimensional steady-state flow field, comprising a probe head (1), a temperature sensor (2), a convection heat exchange groove (3), a heat-insulating seal (4), a temperature sensor cable lead-out channel (5), a pressure measuring middle hole (6), a pressure measuring lower hole (7), a pressure measuring upper hole (8), a pressure measuring right hole (9), a pressure measuring left hole (10), a pressure lead pipe channel (11), a probe support rod (12), a pressure lead pipe (13) and a temperature sensor cable (14), characterized in that: the probe head (1) is cylindrical, the cylindrical A concave ball-socket structure is arranged at the top of the ball socket in a direction perpendicular to the center line of the column. The center line of the ball socket is perpendicular to and intersects with the center line of the column. A pressure measuring middle hole (6) is arranged at the ball socket facing the mainstream direction. A pressure measuring lower hole (7), a pressure measuring upper hole (8), a pressure measuring right hole (9) and a pressure measuring left hole (10) which are not connected to each other are evenly arranged on the side wall of the ball socket. A cross-shaped convection heat exchange groove (3) is arranged on the leeward side of the probe head (1) facing away from the ball socket. Different positions of the groove can be used for both air intake and air discharge, and self-adaptation is achieved according to the incoming flow direction, and the flow of air in the groove is strengthened.

[0037] The probe head (1) is cylindrical and has a diameter of 8 mm and a length of 45 mm. Five mutually unconnected circular pressure-conducting pipe channels (11) and a circular temperature sensor cable lead-out channel (5) are provided along the axial direction of the probe. The five circular pressure-conducting pipe channels (11) are respectively connected to a pressure measuring middle hole (6), a pressure measuring lower hole (7), a pressure measuring upper hole (8), a pressure measuring right hole (9), and a pressure measuring left hole (10) in a ball socket of the probe head, and are respectively connected to five pressure-conducting pipes (13) encapsulated at the connection between the probe head (1) and the probe support rod (12). The pressure-conducting pipes (13) are led out of the tail of the probe support rod (12) through the pressure-conducting pipe channels (11) in the probe support rod (12).

[0038] The diameter of the concave ball socket structure arranged perpendicular to the center line of the cylinder of the probe head (1) is 6 mm, the center of the ball is located on the side surface of the cylinder of the probe head (1), the height of the center line of the ball socket from the end surface of the probe head (1) is 4 mm, the pressure measuring middle hole (6), the pressure measuring lower hole (7), the pressure measuring upper hole (8), the pressure measuring right hole (9) and the pressure measuring left hole (10) are all circular and have the same diameter of 1 mm, the center line of the pressure measuring middle hole (6) coincides with the center line of the ball socket, the pressure measuring lower hole (7), the pressure measuring upper hole (8), the pressure measuring right hole (9) and the pressure measuring left hole (10) are located at the same axial position of the center line of the ball socket and are evenly distributed around the ball socket, and their center lines are perpendicular to the side wall of the ball socket and form an angle of 60° with the center line of the pressure measuring middle hole.

[0039] The convection heat exchange grooves (3) are rectangular with the same width and the centers overlap. The width is 3 mm. The length of the groove parallel to the center line of the probe head (1) cylinder is 6 mm. The depth of the groove perpendicular to the center line reaches the position of the temperature sensor (2) head. The diameter of the circular channel where the temperature sensor (2) head is located is 3 mm. The axial length of the circular channel is 7 mm. The axis of the circular channel overlaps with the axis of the temperature sensor cable lead-out channel (5). The center axis of the temperature sensor cable lead-out channel (5) is 1.5 mm away from the center line of the column. The center axis of the temperature sensor cable lead-out channel (5), the center line of the column and the center line of the pressure measuring hole (6) are on the same plane. The temperature sensor (2) head is located at the circular temperature sensor cable lead-out channel. The temperature sensor (2) is fixed by a heat-insulating seal (4) at the intersection of the axis of the outlet channel (5) and the center line of the pressure measuring hole (6), and is directly opposite to the rectangular center of the convection heat exchange groove (3). The heat-insulating seal (4) plays the role of heat insulation, insulation, sealing and fixing. When installing the heat-insulating seal (4) and the temperature sensor (2), the temperature sensor (2) and the heat-insulating seal (4) are first installed and fixed on the circular channel, and the temperature sensor cable (14) is led out of the tail of the probe support rod (12) through the temperature sensor cable lead-out channel (5) in the probe, and then the opening on the end face of the probe head (1) is covered and welded to seal, and the cylindrical axis of the probe head (1) coincides with the cylindrical axis of the probe support rod (12).

[0040] The probe for measuring all parameters of a subsonic three-dimensional steady-state flow field of the present invention can measure the total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, pitch angle, speed and density of the subsonic three-dimensional steady-state flow field. The specific use method is as follows:

[0041] Step 1: In a calibrated wind tunnel with known Mach number and temperature, allow the incoming flow to flow over the probe head;

[0042] Step 2: Measure the pressure of the five pressure sensing holes on the windward side of the probe and the temperature of the leeward side temperature sensor under different working conditions;

[0043] Step 3: Determine the calibration curves of total pressure coefficient, static pressure coefficient, deflection angle coefficient and total temperature recovery coefficient at different Mach numbers, different deflection angles and pitch angles through data processing based on the data obtained by calibration. The deflection angle coefficient, pitch angle coefficient, total pressure coefficient, static pressure coefficient and temperature recovery coefficient are defined as follows:

[0044]

[0045]

[0046]

[0047]

[0048]

[0049]

[0050] Among them, C py is the deflection angle coefficient, C pp is the pitch angle coefficient, C pt is the total pressure coefficient, C ps is the static pressure coefficient, C T is the temperature recovery coefficient, and the total pressure, static pressure, total temperature and static temperature of the incoming flow in the calibration wind tunnel are P t , P s , T t and T s The pressure values ​​measured by the middle hole, left hole, right hole, upper hole and lower hole of the five-hole pressure probe are P1, P2, P3, P4 and P5 respectively, and the temperature value measured by the temperature sensor is T p .

[0051] Step 4: When in use, insert the probe of the present invention into the flow field to be measured, obtain the pressure measured by the five pressure measuring holes and the temperature measured by the temperature sensor, based on the pressure measured by the five pressure measuring holes and the temperature data measured by the temperature sensor, according to the calibration coefficient curve in the experimental calibration, combined with the following formula, the total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, pitch angle, velocity, and density of the three-dimensional steady-state flow field are obtained.

[0052]

[0053]

[0054]

[0055] c 2 =γRT s

[0056] P S = ρRTS

[0057] Among them, γ is the adiabatic index of the flow field, Ma is the Mach number of the flow field, v is the flow field velocity, c is the local sound speed of the flow field, ρ is the incoming flow density, and R is the gas constant.

[0058] That is, the total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, pitch angle, speed and density of the subsonic three-dimensional steady-state flow field can be obtained by using a single probe of the present invention.

[0059] Implementation case 2:

[0060] For the measurement of the three-dimensional flow field between the impeller stages, the measurement space is narrow and the three-dimensionality of the incoming flow is strong. In order to ensure the spatial resolution, a smaller lateral dimension of the probe head and a smaller diameter of the pressure measuring hole should be selected. The temperature sensor can use a smaller bare wire thermocouple to ensure refined measurement and improve measurement accuracy. Therefore, the following implementation method can be adopted:

[0061] like Figures 6 to 8 The figure shows a probe for measuring all parameters of a subsonic three-dimensional steady-state flow field according to the present invention. Fig. 9 The present invention is a schematic diagram of a probe for measuring the three-dimensional flow field between compressor stages. The present invention is a probe for measuring all parameters of a subsonic three-dimensional steady-state flow field, comprising a probe head (1), a temperature sensor (2), a convection heat exchange groove (3), a heat-insulating seal (4), a temperature sensor cable lead-out channel (5), a pressure measuring middle hole (6), a pressure measuring lower hole (7), a pressure measuring upper hole (8), a pressure measuring right hole (9), a pressure measuring left hole (10), a pressure lead pipe channel (11), a probe support rod (12), a pressure lead pipe (13) and a temperature sensor cable (14). The invention is characterized in that: the probe head (1) is cylindrical, and an inwardly concave ball-socket structure is arranged at the top of the cylinder perpendicular to the center line of the cylinder, the center line of the ball-socket is perpendicular to and intersects with the center line of the cylinder, a pressure measuring middle hole (6) is arranged at the ball-socket facing the mainstream direction, and a pressure measuring lower hole (7), a pressure measuring upper hole (8), a pressure measuring right hole (9) and a pressure measuring left hole (10) which are not connected to each other are evenly arranged on the side wall of the ball-socket, and a cross-shaped convection heat exchange groove (3) is arranged on the leeward side of the probe head (1) facing away from the ball-socket.

[0062] The probe head (1) is cylindrical and has a diameter of 3 mm and a length of 10 mm. Five mutually unconnected circular pressure-conducting pipe channels (11) and a circular temperature sensor cable lead-out channel (5) are provided along the axial direction of the probe. The five circular pressure-conducting pipe channels (11) are respectively connected to a pressure measuring middle hole (6), a pressure measuring lower hole (7), a pressure measuring upper hole (8), a pressure measuring right hole (9), and a pressure measuring left hole (10) in the ball socket of the probe head (1), and are respectively connected to five pressure-conducting pipes (13) encapsulated at the connection between the probe head (1) and the probe support rod (12). The pressure-conducting pipes (13) are led out of the tail of the probe support rod (12) through the pressure-conducting pipe channels (11) in the probe support rod (12).

[0063] The diameter of the concave ball socket structure arranged perpendicular to the center line of the cylinder of the probe head (1) is 2 mm, the distance between the center of the ball and the side surface of the cylinder of the probe head (1) is 1 / 6 times the diameter of the ball socket, the height of the center line of the ball socket from the end face of the probe head (1) is 1.5 mm, the pressure measuring middle hole (6), the pressure measuring lower hole (7), the pressure measuring upper hole (8), the pressure measuring right hole (9), and the pressure measuring left hole (10) are all circular and have the same diameter of 0.3 mm, the center line of the pressure measuring middle hole (6) coincides with the center line of the ball socket, the pressure measuring lower hole (7), the pressure measuring upper hole (8), the pressure measuring right hole (9), and the pressure measuring left hole (10) are located at the same axial position of the center line of the ball socket and are evenly distributed around the ball socket, and their center lines are perpendicular to the side wall of the ball socket and form an angle of 30° with the center line of the pressure measuring middle hole (6).

[0064] The convection heat exchange grooves (3) are rectangular with the same width and the centers overlap. The width is 1.5 mm. The length of the groove parallel to the center line of the probe head (1) is 2 mm. The depth of the groove perpendicular to the center line reaches the position of the temperature sensor head. The diameter of the circular channel where the temperature sensor head is located is 1 mm. The axial length of the circular channel is 3 mm. The axis of the circular channel overlaps with the axis of the temperature sensor cable lead-out channel (5). The center axis of the temperature sensor cable lead-out channel (5) is 0.5 mm away from the center line of the column. The center axis of the temperature sensor cable lead-out channel (5), the center line of the column and the center line of the pressure measuring hole (6) are on the same plane. The head of the temperature sensor (2) is located at the circular temperature sensor cable lead-out channel. The temperature sensor (2) is fixed by a heat-insulating seal (4), which plays the role of heat insulation, insulation, sealing and fixing. When installing the heat-insulating seal (4) and the temperature sensor (2), the temperature sensor (2) and the heat-insulating seal (4) are first installed and fixed on the circular channel, and the temperature sensor cable (14) is led out of the tail of the probe support rod (12) through the temperature sensor cable lead-out channel (5) in the probe, and then the opening on the end face of the probe head (1) is covered and welded to seal, and the cylindrical axis of the probe head (1) coincides with the cylindrical axis of the probe support rod (12).

Claims

1. A method for using a probe for measuring all parameters of a subsonic three-dimensional steady-state flow field to realize a subsonic three-dimensional steady-state flow field at an inlet and outlet and between stages of a fan compressor or the like in a turbomachinery, wherein the structure of the probe for measuring all parameters of a subsonic three-dimensional steady-state flow field is composed of a probe head (1), a temperature sensor (2), a convection heat exchange groove (3), a heat-insulating seal (4), a temperature sensor cable lead-out channel (5), a pressure measuring middle hole (6), a pressure measuring lower hole (7), a pressure measuring upper hole (8), a pressure measuring right hole (9), a pressure measuring left hole (10), a pressure lead pipe channel (11), a probe support rod (12), a pressure lead pipe (13) and a temperature sensor cable (14), and is characterized in that: The probe head (1) is cylindrical, and an inwardly concave ball-socket structure is arranged at the top of the cylinder perpendicular to the center line of the cylinder. The center line of the ball-socket is perpendicular to and intersects with the center line of the cylinder. A pressure measuring middle hole (6) is arranged at the ball-socket facing the mainstream direction, and mutually unconnected pressure measuring lower holes (7), pressure measuring upper holes (8), pressure measuring right holes (9), and pressure measuring left holes (10) are evenly arranged on the side walls of the ball-socket. A cross-shaped convection heat exchange groove (3) is arranged on the leeward side of the probe head (1) facing away from the ball-socket. Different positions of the groove can both inlet and outlet air, and can achieve self-adaptation with the incoming flow direction, and strengthen the flow of air in the groove. The probe head (1) is cylindrical and has a diameter of 2 to 8 mm and a length of 5 to 45 mm. Five mutually unconnected circular pressure-inducing pipe channels (11) and a circular temperature sensor cable lead-out channel (5) are provided along the axial direction of the probe. The five circular pressure-inducing pipe channels (11) are respectively connected to a pressure measuring middle hole (6), a pressure measuring lower hole (7), a pressure measuring upper hole (8), a pressure measuring right hole (9), and a pressure measuring left hole (10) in the ball socket of the probe head (1), and are respectively connected to five pressure-inducing pipes (13) encapsulated at the connection between the probe head (1) and the probe support rod (12). The pressure-inducing pipes (13) are led out of the tail of the probe support rod (12) through the pressure-inducing pipe channels (11) in the probe support rod (12). The diameter of the concave ball socket structure arranged perpendicular to the center line of the cylinder of the probe head (1) is 1 to 6 mm, the distance between the center of the ball and the side surface of the cylinder of the probe head (1) is 0 to 1 / 6 times the diameter of the ball socket, the height of the center line of the ball socket from the end face of the probe head is 0.5 to 4 mm, the pressure measuring middle hole (6), the pressure measuring lower hole (7), the pressure measuring upper hole (8), the pressure measuring right hole (9) and the pressure measuring left hole (10) are all circular and have the same diameter of 0.1 to 1.5 mm, the center line of the pressure measuring middle hole (6) coincides with the center line of the ball socket, the pressure measuring lower hole (7), the pressure measuring upper hole (8), the pressure measuring right hole (9) and the pressure measuring left hole (10) are located at the same axial position of the center line of the ball socket and are evenly distributed around the ball socket, and their center lines are perpendicular to the side wall of the ball socket and form an angle of 20° to 80° with the center line of the pressure measuring middle hole; The convection heat exchange grooves (3) are rectangular with the same width and the centers overlap. The width is 1 to 3 mm. The length of the groove parallel to the center line of the probe head (1) cylinder is 0.8 to 6 mm. The depth of the groove perpendicular to the center line reaches the position of the temperature sensor (2) head. The diameter of the circular channel where the temperature sensor (2) head is located is 0.8 to 3.5 mm. The axial length of the circular channel is 1 to 7 mm. The axis of the circular channel overlaps with the axis of the temperature sensor cable lead-out channel (5). The center axis of the temperature sensor cable lead-out channel (5) is 0.5 to 3 mm away from the center line of the column. The center axis of the temperature sensor cable lead-out channel (5), the center line of the column and the center line of the pressure measuring hole (6) are on the same plane. The temperature sensor (2) head is located in the circular channel. The temperature sensor (2) is fixed by a heat-insulating seal (4) at the intersection of the axis of the temperature sensor cable lead-out channel (5) and the center line of the pressure measuring hole (6), and is directly opposite to the rectangular center of the convection heat exchange groove (3). The heat-insulating seal (4) plays the role of heat insulation, insulation, sealing and fixing. When installing the heat-insulating seal (4) and the temperature sensor (2), the temperature sensor (2) and the heat-insulating seal (4) are first installed and fixed on the circular channel. The temperature sensor cable (14) is led out of the tail of the probe support rod (12) through the temperature sensor cable lead-out channel (5) in the probe, and then the opening on the end face of the probe head (1) is covered and welded to seal. The cylindrical axis of the probe head (1) coincides with the cylindrical axis of the probe support rod (12); The use steps are as follows: Step 1: in a calibrated wind tunnel with known incoming flow Mach number and temperature, allow incoming flow to flow through the probe head; Step 2: measure the pressure of the five pressure sensing holes on the windward side of the probe and the temperature of the leeward side temperature sensor under different working conditions; Step 3: Determine the calibration curves of total pressure coefficient, static pressure coefficient, deflection angle coefficient and total temperature recovery coefficient at different Mach numbers, deflection angles and pitch angles through data processing based on the data obtained by calibration; Step 4: When in use, insert the probe of the present invention into the flow field to be measured, obtain the pressure measured by the five pressure measuring holes and the temperature measured by the temperature sensor, based on the pressure measured by the five pressure measuring holes and the temperature data measured by the temperature sensor, according to the calibration coefficient curve in the experimental calibration, combined with the formula, the total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, pitch angle, velocity, and density of the three-dimensional steady-state flow field are obtained.

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