A full-parameter probe for measuring the two-dimensional steady flow field of the boundary layer on the outer wall of the hub

Abstract

The present invention belongs to the technical field of flow field testing, and discloses a full-parameter probe for measuring the two-dimensional steady flow field of the boundary layer on the outer wall of a hub, which includes a probe head, pressure sensing holes, a temperature sensor, an adiabatic and insulating seal, a pressure guiding tube, a temperature sensor cable, a temperature sensor cable lead-out channel, a pressure guiding tube lead-out channel, and a probe strut. The probe head is cylindrical, and three non-connecting pressure sensing holes arranged in a "pin" shape are disposed on the windward surface; an arc groove is axially formed on the leeward surface of the probe head, and the temperature sensor is placed in the arc groove to avoid the direct impact of the mainstream on the temperature sensor. Compared with the existing boundary layer probes, the present invention can simultaneously measure the total temperature, static temperature, total pressure, static pressure, deflection angle, Mach number, density, and two-dimensional velocity of the two-dimensional steady flow field in the boundary layer on the outer wall of the hub, and can also take into account the measurement of the flow field in the boundary layer in the inlet of an aeroengine, and has the characteristics of small size, high spatial resolution, high measurement accuracy, and high reliability.

Description

Technical Field

[0001] The present invention belongs to the technical field of flow field testing, and specifically relates to a full-parameter probe for measuring the two-dimensional steady flow field of the boundary layer on the outer wall of a hub. The probe is suitable for measuring the two-dimensional complex flow field in the boundary layer on the hub side of the inlet, outlet and impeller stage of compressors, fans and compressors, and can also take into account the flow field measurement in the boundary layer in the air inlet of an aircraft engine. Background Art

[0002] Due to the viscosity of air flow, a boundary layer will form on the outer wall of the hub at the inlet, outlet and impeller stages of aircraft engine inlets, compressors, fans, compressors, etc., especially at the compressor outlet and impeller stages. The rotation of the rotor, the staggered arrangement of the moving and stationary blade rows, and the interaction between the blade wakes and the boundary layer lead to complex flow in the boundary layer of the outer wall of the hub. Therefore, it has always been a challenge for researchers to accurately measure the flow field parameters in the boundary layer on the hub side.

[0003] At present, for the measurement of flow field in the boundary layer, the boundary layer total pressure probe and the hot wire anemometer are generally used to measure the total pressure and velocity respectively. When the above devices are used alone to measure the boundary layer flow field, on the one hand, the measurement time is long, the flow in the boundary layer will undergo certain changes, and the test cost is high; on the other hand, the measurement point positions of different devices may be affected by the positioning of the displacement mechanism, which may lead to different measurement positions. Therefore, the flow parameters measured by different devices are definitely not the same streamline, resulting in large errors in the measurement results.

[0004] Most of the existing three-hole pressure probes have three pressure measuring holes arranged in a straight line on the probe head, and the diameters of the pressure measuring holes are the same, so a larger layout space is required, resulting in a larger lateral dimension of the probe head, i.e., a larger diameter of the probe head, and thus a lower spatial resolution; and a larger circumferential angle between the left and right pressure measuring holes along the probe head surface, so a smaller measurement range of the airflow deflection angle.

[0005] According to the design ideas of the existing total temperature probe or temperature and pressure combination probe, most of them are designed to face the mainstream. The temperature probe head adopts a stagnation cover structure to collect the incoming flow, and the temperature sensor is placed in the stagnation cover. Its disadvantages are: first, the incoming flow directly impacts the temperature sensor, which is easily damaged by impurities such as oil droplets and dust in the incoming flow; second, the insensitive angle range of the total temperature measurement is small. When the incoming flow to be measured has a large deflection angle, the airflow cannot be fully stagnant, and the heat exchange on the surface of the temperature sensor is insufficient, so the total temperature measurement error is large; third, the strength of the temperature sensor is usually improved by increasing the size of the temperature sensor, and coupled with the size of the stagnation cover, this will lead to a larger probe size and poor spatial resolution.

[0006] All of the above problems restrict the researchers' in-depth understanding of the flow field within the boundary layer. In particular, if the data obtained separately by a boundary layer total pressure probe and a hot wire anemometer are combined for processing, it will introduce significant errors. Generally, in existing temperature-pressure combined probes, the temperature sensor and the pressure sensing holes are placed simultaneously on the windward side of the probe head, which requires a large layout space and results in poor spatial resolution. Therefore, it is difficult to meet the requirements for spatial resolution when measuring the boundary layer flow field and is not suitable for the precise measurement of all parameters of the two-dimensional flow field within the boundary layer. However, researchers hope to obtain the parameter information of the flow field within the boundary layer simultaneously and precisely. Therefore, there is an urgent need for a full-parameter probe for measuring the two-dimensional complex flow field within the boundary layer of the outer wall of the hub, which is used for the measurement of all parameters such as the total temperature, static temperature, total pressure, static pressure, deflection angle, Mach number, density, and velocity of the two-dimensional complex flow field within the boundary layer on the inlet, outlet, and impeller stage between the hubs of compressors, fans, and compressors. Summary of the Invention

[0007] Aiming at the problems that the current boundary layer probes can only measure the total pressure or velocity separately, resulting in large measurement errors, and the temperature-pressure combined probes cannot meet the measurement accuracy of the boundary layer flow field and the temperature sensor is easily damaged when facing the mainstream, a full-parameter probe is proposed that can simultaneously measure the total temperature, static temperature, total pressure, static pressure, deflection angle, Mach number, density, and velocity of the two-dimensional steady flow field within the boundary layer of the outer wall of the hub. In the windward side of the probe head of the probe of the present invention, three non-communicating pressure sensing holes arranged in a "pin" shape are arranged. Compared with the traditional three-hole pressure probe with the three pressure sensing holes arranged in a "one" shape, it can effectively reduce the lateral dimension of the probe head, that is, the diameter of the probe head, greatly improve the spatial resolution of the flow field measurement and the measurement range of the airflow deflection angle, and reduce the interference of the probe head on the boundary layer flow field. The present invention abandons the design idea of the traditional total temperature probe, but based on the applicant's years of research, creatively proposes the layout and structural design of placing the temperature sensor on the leeward side of the probe head, and the temperature sensor is directly opposite to the middle pressure sensing hole, which can ensure the multi-parameter measurement of the same streamline; it can also avoid the impact of the airflow on the temperature sensor and the influence of dust and oil droplets in the airflow on the temperature sensor, improving the service life of the temperature sensor; it is beneficial to strengthen the convective heat transfer between the airflow and the temperature sensor, and the temperature recovery coefficient is high and stable within a large deflection angle range; it effectively reduces the size of the probe head, improves the spatial resolution, and reduces the influence of the probe head on the boundary layer flow field. Most importantly, the present invention can simultaneously measure the total temperature, static temperature, total pressure, static pressure, deflection angle, Mach number, density, and velocity of the two-dimensional steady flow field within the boundary layer, making up for the deficiencies of the traditional two-dimensional boundary layer flow field measurement.

[0008] The technical solution of the present invention is as follows:

[0009] 1. A full-parameter probe for measuring the two-dimensional steady-state flow field of the boundary layer of the outer wall of a wheel hub, comprising a probe head (1), a probe support rod (2), a pressure sensing left hole (3), a pressure sensing middle hole (4), a pressure sensing right hole (5), a heat-insulating seal (6), an arc groove (7), a temperature sensor (8), a temperature sensing hole (9), a temperature sensor cable lead-out channel (10), a pressure lead-out channel (11), a temperature sensor cable (12) and a pressure lead-out tube (13), characterized in that: the probe head ( 1) is a cylindrical structure, three mutually unconnected pressure sensing holes are opened on the windward side of the probe head (1), namely, a left pressure sensing hole (3), a middle pressure sensing hole (4), and a right pressure sensing hole (5), an arc groove (7) is opened on the leeward side of the probe head (1) directly opposite to the middle pressure sensing hole (4), a temperature sensing hole (9) is opened in the arc groove (7), a temperature sensor (8) is placed in the arc groove (7), and a heat-insulating sealing member (6) is located in the temperature sensing hole (9) for fixing the temperature sensor (8).

[0010] 2. Furthermore, the diameter of the cylindrical body of the probe head (1) is 0.8 mm to 4 mm, and the length is 6 mm to 50 mm. A temperature sensor cable lead-out channel (10) and three mutually unconnected pressure lead-out channels (11) are axially opened in the probe head (1). The three pressure lead-out channels (11) are respectively connected to the pressure sensing left hole (3), the pressure sensing middle hole (4), and the pressure sensing right hole (5). The pressure lead-out tube (13) is respectively connected to the pressure sensing left hole (3), the pressure sensing middle hole (4), and the pressure sensing right hole (5) and is led out of the tail of the probe support rod (2) through the pressure lead-out channel (11). The temperature sensor cable (12) is led out of the tail of the probe support rod (2) through the temperature sensor cable lead-out channel (10). The axis of the cylindrical body of the probe head (1) coincides with the axis of the cylindrical body of the probe support rod (2).

[0011] 3. Furthermore, the pressure sensing middle hole (4) is elliptical and has an inner chamfer of 30° to 60°, with a major axis of 0.3 mm to 1.5 mm and a minor axis of 0.15 mm to 0.7 mm. The distance between its center line and the top surface of the probe head (1) is 0.3 mm to 0.7 mm, and it is perpendicular to the axis of the probe head (1) and on the same plane. The pressure sensing left hole (3) and the pressure sensing right hole (5) are circular and symmetrically distributed along the plane. The diameters are the same, both of which are 0.1 mm to 0.5 mm. The distance between their center lines and the top surface of the probe head (1) is 0.6 mm to 1.5 mm. The center lines of the pressure sensing left hole (3) and the pressure sensing right hole (5) intersect with the axis of the probe head (1) and are on the same circumferential surface. The circumferential surface is perpendicular to the axis of the probe head (1). The circumferential angles of the center lines of the pressure sensing left hole (3) and the pressure sensing right hole (5) on the cylindrical surface of the probe head (1) are 30° to 80°.

[0012] 4. Further, the arc surface of the arc groove (7) on the leeward side of the probe head (1) is a third of a circle with a diameter of 0.3 mm to 1.5 mm. The arc groove (7) is symmetrical about the center line of the pressure sensing hole (4), and its axis is parallel to the axis of the probe head (1). The length of the arc groove (7) along the axis of the probe head (1) is 0.6 mm to 1.4 mm. The temperature sensing hole (9) is circular with a diameter of 0.15 mm to 0.7 mm. Its center line coincides with the center line of the pressure sensing hole (4) and is 0.3 mm to 0.7 mm away from the top surface of the probe head (1). The head of the temperature sensor (8) is located on the center line of the temperature sensing hole (9) and close to the leeward side of the probe head (1). It is fixed by the heat-insulating seal (6) and is 0.3 mm to 1.8 mm away from the axis of the probe head (1).

[0013] 5. After the probe of the present invention is calibrated in a calibration wind tunnel, a probe calibration curve is obtained. In actual measurement, based on the data measured by the pressure sensing left hole (3), the pressure sensing middle hole (4), the pressure sensing right hole (5) and the temperature sensor (8), and then according to the calibration coefficient curve and formula obtained by the calibration wind tunnel, through data processing, all parameters such as the total temperature, static temperature, total pressure, static pressure, deflection angle, Mach number, density and speed of the two-dimensional steady-state flow field of the boundary layer of the outer wall of the hub can be obtained at the same time, thereby increasing the life of the temperature sensor (8) and the airflow insensitive angle range, and having the characteristics of high spatial resolution, high precision and high reliability.

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

[0015] Beneficial effect 1: The traditional boundary layer probe can only measure the total pressure or velocity separately, while the present invention can simultaneously measure the total temperature, static temperature, total pressure, static pressure, deflection angle, Mach number, density and two-dimensional velocity of the two-dimensional steady-state flow field in the boundary layer, solving the problems of long measurement time, high test cost, poor consistency of measurement conditions and large measurement error caused by the traditional solution of using boundary layer pressure probe and hot wire anemometer to measure total pressure and velocity respectively;

[0016] Beneficial effect 2: Traditional temperature probes and temperature-pressure combination probes place the temperature sensor directly facing the incoming flow, and rely on the incoming flow to stagnate on the temperature sensor to measure the temperature. The airflow directly impacts the temperature sensor, which is easy to damage the temperature sensor, and the measurement insensitive angle is narrow; while the present invention creatively places the temperature sensor on the leeward side of the probe head to avoid the incoming flow from directly impacting the temperature sensor, effectively protecting the temperature sensor, and reducing the impact of impurities such as dust and oil droplets in the incoming flow on the temperature sensor, thereby ensuring measurement accuracy and extending the service life of the temperature sensor.

[0017] Beneficial effect three: When measuring the boundary layer flow field, the boundary layer is relatively thin, but the total pressure gradient is large, so the probe must have a sufficiently high spatial resolution. Traditional temperature and pressure probes place the temperature sensor and the pressure sensing hole on the windward side of the probe head at the same time, which requires a large layout space, resulting in a low spatial resolution and is not suitable for boundary layer measurements. The present invention places the temperature sensor on the leeward side of the probe head and the pressure sensing hole on the windward side facing the temperature sensor, ensuring simultaneous measurement of multiple parameters of the same streamline. The moving probe can achieve multi-horizontal flow field parameter measurement, ensuring a sufficiently high spatial resolution.

[0018] Beneficial effect four: The three pressure sensing holes of the traditional three-hole pressure probe are arranged in a "one" shape on the probe head, while the three sensing holes on the windward side of the probe head of the present invention are in a "pin" shape. The advantage is that the lateral size of the probe head, that is, the diameter of the probe head, can be reduced, thereby reducing the interference of the probe head on the boundary layer flow field to be measured, which is beneficial to improving the measurement accuracy and spatial resolution; the pressure sensing hole is elliptical and chamfered, which will have a larger measurement insensitive angle. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the probe structure in the first embodiment of the present invention.

[0020] Figure 2 yes Figure 1 Rear view of.

[0021] Figure 3 yes Figure 1 Left view of .

[0022] Figure 4 yes Figure 1 A partial sectional view of the left view.

[0023] Figure 5 yes Figure 1 B-direction cross-sectional view.

[0024] Figure 6 yes Figure 1 C-section view.

[0025] Among them: 1—probe head, 2—probe support rod, 3—pressure sensing left hole, 4—pressure sensing middle hole, 5—pressure sensing right hole, 6—thermal insulation seal, 7—arc groove, 8—temperature sensor, 9—temperature sensing hole, 10—temperature sensor cable lead-out channel, 11—pressure pipe lead-out channel, 12—temperature sensor cable, 13—pressure pipe.

[0026] Figure 7 It is a schematic diagram of the probe of the present invention being used to measure the boundary layer of the inlet duct wall.

[0027] Among them: 1—inlet duct wall, 2—inlet duct boundary layer, 3—probe head of the present invention, 4—probe of the present invention, 5—probe head of the present invention, 6—wheel hub outer wall, 7—wheel hub outer wall boundary layer.

[0028] Figure 8 It is a schematic diagram of the probe structure in the second embodiment of the present invention.

[0029] Fig. 9 yes Figure 8 Rear view of.

[0030] Fig.10 yes Figure 8 Left view of .

[0031] Fig.11 yes Figure 8 A partial sectional view of the left view.

[0032] Fig.12 yes Figure 8 B-direction cross-sectional view.

[0033] Fig.13 yes Figure 8 C-section view.

[0034] Among them: 1—probe head, 2—probe support rod, 3—pressure sensing left hole, 4—pressure sensing middle hole, 5—pressure sensing right hole, 6—thermal insulation seal, 7—arc groove, 8—temperature sensor, 9—temperature sensing hole, 10—temperature sensor cable lead-out channel, 11—pressure pipe lead-out channel, 12—temperature sensor cable, 13—pressure pipe.

[0035] Fig.14 The present invention is a schematic diagram of the probe used to measure the boundary layer of the outer wall of the compressor interstage hub.

[0036] Wherein: 1 - first stage stator, 2 - first stage rotor, 3 - probe of the present invention, 4 - second stage stator, 5 - probe head of the present invention, 6 - outer wall of wheel hub, 7 - boundary layer of outer wall of wheel hub DETAILED DESCRIPTION

[0037] 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.

[0038] Implementation case 1:

[0039] 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 rain may be contained. The probe head (1) is selected with a larger diameter to ensure strength and rigidity; the pressure sensing holes (3, 4, 5) can be selected with a larger diameter to prevent contamination by impurities such as dust and rain; the temperature sensor can use an armored thermocouple to ensure life, so the following implementation case can be used:

[0040] Figures 1 to 6 The present invention is a schematic diagram of the structure of a full-parameter probe for measuring the two-dimensional steady flow field of the boundary layer of the outer wall of the hub. Figure 7 It is a schematic diagram of the probe of the present invention being used to measure the boundary layer of the inlet duct wall. The present invention comprises a probe head (1), a probe support rod (2), a pressure sensing left hole (3), a pressure sensing middle hole (4), a pressure sensing right hole (5), a heat-insulating seal (6), an arc groove (7), a temperature sensor (8), a temperature sensing hole (9), a temperature sensor cable lead-out channel (10), a pressure-inducing pipe lead-out channel (11), a temperature sensor cable (12) and a pressure-inducing pipe (13), and is characterized in that: the probe head (1) is a cylindrical structure, three mutually unconnected pressure sensing holes are opened on the windward side of the probe head (1), namely, the pressure sensing left hole (3), the pressure sensing middle hole (4) and the pressure sensing right hole (5), an arc groove (7) is opened on the leeward side of the probe head (1) directly opposite to the pressure sensing middle hole (4), a temperature sensing hole (9) is opened in the arc groove (7), the temperature sensor (8) is placed in the arc groove (7), and the heat-insulating seal (6) is located in the temperature sensing hole (9) and is used to fix the temperature sensor (8).

[0041] In the first step, the diameter of the cylindrical body of the probe head (1) is 4 mm and the length is 50 mm. A temperature sensor cable lead-out channel (10) and three mutually unconnected pressure lead-out channels (11) are opened in the axial direction of the probe head (1). The three pressure lead-out channels (11) are respectively connected to the pressure sensing left hole (3), the pressure sensing middle hole (4) and the pressure sensing right hole (5). The pressure lead-out tube (13) is respectively connected to the pressure sensing left hole (3), the pressure sensing middle hole (4) and the pressure sensing right hole (5) and leads out of the tail of the probe support rod (2) through the pressure lead-out channel (11). The temperature sensor cable (12) is led out of the tail of the probe support rod (2) through the temperature sensor cable lead-out channel (10). The axis of the cylindrical body of the probe head (1) coincides with the axis of the cylindrical body of the probe support rod (2).

[0042] The pressure sensing middle hole (4) is elliptical and has a 60° chamfer, a major axis of 1.5 mm, a minor axis of 0.7 mm, a center line of which is 0.7 mm away from the top surface of the probe head (1), and is perpendicular to the axis of the probe head (1) and on the same plane. The pressure sensing left hole (3) and the pressure sensing right hole (5) are circular and symmetrically distributed along the plane. They have the same diameter of 0.5 mm and a center line of which is 1.5 mm away from the top surface of the probe head (1). The center lines of the pressure sensing left hole (3) and the pressure sensing right hole (5) intersect with the axis of the probe head (1) and are on the same circumferential surface. The circumferential surface is perpendicular to the axis of the probe head (1). The circumferential angle between the center lines of the pressure sensing left hole (3) and the pressure sensing right hole (5) on the cylindrical surface of the probe head (1) is 80°.

[0043] The arc surface of the arc groove (8) on the leeward side of the probe head (1) is one-third of a circle with a diameter of 1.5 mm. The arc groove (8) is symmetrical about the center line of the pressure sensing hole (4), and its axis is parallel to the axis of the probe head (1). The length of the arc groove (8) along the axis of the probe head (1) is 1.4 mm. The temperature sensing hole (9) is circular with a diameter of 0.7 mm. Its center line coincides with the center line of the pressure sensing hole (4) and is 0.7 mm away from the top surface of the probe head (1). The temperature sensor (8) is located on the center line of the temperature sensing hole (9) and close to the leeward side of the probe head (1). It is fixed by a heat-insulating seal (6) and is 1.8 mm away from the axis of the probe head (1).

[0044] After the probe of the present invention is calibrated in a calibration wind tunnel, a probe calibration curve is obtained. In actual measurement, based on the data measured by the pressure sensing left hole (3), the pressure sensing middle hole (4), the pressure sensing right hole (5) and the temperature sensor (8), and then according to the calibration coefficient curve and formula obtained by the calibration wind tunnel, through data processing, all parameters such as the total temperature, static temperature, total pressure, static pressure, deflection angle, Mach number, density and speed of the two-dimensional steady-state flow field of the boundary layer of the outer wall of the wheel hub can be obtained simultaneously, thereby increasing the service life of the temperature sensor (8) and the airflow insensitive angle range, and having the characteristics of high spatial resolution, high precision and high reliability.

[0045] The present invention needs to be calibrated in a standard wind tunnel before use. The probe is placed in a uniform incoming flow. When the incoming flow velocity and angle are known, the total pressure coefficient, static pressure coefficient, deflection angle coefficient and total temperature recovery coefficient at different Mach numbers are calibrated.

[0046] The specific steps include:

[0047] Step A: In a standard wind tunnel with known Mach number and velocity of incoming flow, allow the incoming flow to flow over the probe head;

[0048] Step B: Measure the pressure of three pressure sensing holes on the windward surface of the probe;

[0049] Step C: measuring the temperature of the temperature sensor on the leeward side of the probe;

[0050] Step D: Define the pressure measured by the left pressure sensing hole (3) as P1, the pressure measured by the middle pressure sensing hole (4) as P2, the pressure measured by the right pressure sensing hole (5) as P3, and the temperature measured by the temperature sensor (10) as T s , the total pressure of the incoming flow is P t , the static pressure of the incoming flow is P s , the total temperature of the incoming flow is T t , the static temperature of the incoming flow is T s From this, we can get the total pressure coefficient, static pressure coefficient, deflection angle coefficient, and total temperature recovery coefficient under different incoming flow Mach numbers. The definitions of each coefficient are as follows:

[0051] Total pressure coefficient:

[0052] Static pressure coefficient:

[0053] Deflection angle coefficient:

[0054] Temperature recovery coefficient:

[0055] Thus, the calibration curves of total pressure coefficient, static pressure coefficient, deflection angle coefficient and total temperature recovery coefficient at different Mach numbers and deflection angles can be obtained.

[0056] The measuring process of the present invention comprises the following steps:

[0057] Step A: placing the probe head in the abortion to be tested, and allowing the fluid to be tested to flow through the probe head;

[0058] Step B: Measure the pressure of three pressure sensing holes on the windward side;

[0059] Step C: measuring the temperature of the leeward temperature sensor;

[0060] Step D: Based on the data from the three pressure sensing holes and the temperature data measured by the temperature sensor, the deflection angle coefficient is calculated, and then combined with the calibrated coefficient curve, the deflection angle, total pressure, static pressure and Mach number are interpolated. The incoming flow velocity and density can be solved using the following formula:

[0061]

[0062]

[0063]

[0064] c 2 =γRTs

[0065] P s = ρRT s

[0066] 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.

[0067] Implementation case 2:

[0068] For the boundary layer of the outer wall of the impeller hub between stages, the measurement space is narrow, the boundary layer is thin, the incoming flow is highly two-dimensional, has a large deflection angle, but the speed is relatively small. In order to ensure spatial resolution, the probe head (1) can be selected with a smaller diameter, and the pressure sensing holes (3, 4, 5) can also be selected with a smaller diameter to ensure fine measurement. The temperature sensor can use a smaller bare wire thermocouple to improve the measurement accuracy. Therefore, the following implementation case can be used:

[0069] Figures 8 to 13 The schematic diagram of the structure of a full-parameter probe for measuring the two-dimensional steady flow field of the boundary layer on the outer wall of the hub according to the present invention is shown in FIG. Fig.14 The present invention is a schematic diagram of the probe used to measure the boundary layer of the outer wall of the compressor interstage hub. The present invention comprises a probe head (1), a probe support rod (2), a pressure sensing left hole (3), a pressure sensing middle hole (4), a pressure sensing right hole (5), a heat-insulating seal (6), an arc groove (7), a temperature sensor (8), a temperature sensing hole (9), a temperature sensor cable lead-out channel (10), a pressure-inducing pipe lead-out channel (11), a temperature sensor cable (12) and a pressure-inducing pipe (13), and is characterized in that: the probe head (1) is a cylindrical structure, three mutually unconnected pressure sensing holes are opened on the windward side of the probe head (1), namely, the pressure sensing left hole (3), the pressure sensing middle hole (4) and the pressure sensing right hole (5), an arc groove (7) is opened on the leeward side of the probe head (1) directly opposite to the pressure sensing middle hole (4), a temperature sensing hole (9) is opened in the arc groove (7), the temperature sensor (8) is placed in the arc groove (7), and the heat-insulating seal (6) is located in the temperature sensing hole (9) and is used to fix the temperature sensor (8).

[0070] In the first step, the diameter of the cylindrical body of the probe head (1) is 0.8 mm and the length is 6 mm. A temperature sensor cable lead-out channel (10) and three mutually unconnected pressure lead-out channels (11) are opened in the axial direction of the probe head (1). The three pressure lead-out channels (11) are respectively connected to the pressure sensing left hole (3), the pressure sensing middle hole (4) and the pressure sensing right hole (5). The pressure lead-out tube (13) is respectively connected to the pressure sensing left hole (3), the pressure sensing middle hole (4) and the pressure sensing right hole (5) and leads out of the tail of the probe support rod (2) through the pressure lead-out channel (11). The temperature sensor cable (12) is led out of the tail of the probe support rod (2) through the temperature sensor cable lead-out channel (10). The axis of the cylindrical body of the probe head (1) coincides with the axis of the cylindrical body of the probe support rod (2).

[0071] The pressure sensing middle hole (4) is elliptical and has a 30° inner chamfer. The major axis is 0.3 mm and the minor axis is 0.15 mm. The distance between its center line and the top surface of the probe head (1) is 0.3 mm. It is perpendicular to the axis of the probe head (1) and on the same plane. The pressure sensing left hole (3) and the pressure sensing right hole (5) are circular and symmetrically distributed along the plane. The diameters are the same, both 0.1 mm. The distance between their center lines and the top surface of the probe head (1) is 0.6 mm to 1.5 mm. The center lines of the pressure sensing left hole (3) and the pressure sensing right hole (5) intersect with the axis of the probe head (1) and are on the same circumferential surface. The circumferential surface is perpendicular to the axis of the probe head (1). The circumferential angle between the center lines of the pressure sensing left hole (3) and the pressure sensing right hole (5) on the cylindrical surface of the probe head (1) is 30°.

[0072] The arc surface of the arc groove (8) on the leeward side of the probe head (1) is one-third of a circle with a diameter of 0.3 mm. The arc groove (8) is symmetrical about the center line of the pressure sensing hole (4), and its axis is parallel to the axis of the probe head (1). The length of the arc groove (8) along the axis of the probe head (1) is 0.6 mm. The temperature sensing hole (9) is circular with a diameter of 0.15 mm. Its center line coincides with the center line of the pressure sensing hole (4) and is 0.3 mm away from the top surface of the probe head (1). The temperature sensor (8) is located on the center line of the temperature sensing hole (9) and close to the leeward side of the probe head (1), and is fixed by a heat-insulating seal (6) and is 0.3 mm away from the axis of the probe head (1).

[0073] After the probe of the present invention is calibrated in a calibration wind tunnel, a probe calibration curve is obtained. In actual measurement, based on the data measured by the pressure sensing left hole (3), the pressure sensing middle hole (4), the pressure sensing right hole (5) and the temperature sensor (8), and then according to the calibration coefficient curve and formula obtained by the calibration wind tunnel, through data processing, all parameters such as the total temperature, static temperature, total pressure, static pressure, deflection angle, Mach number, density and speed of the two-dimensional steady-state flow field of the boundary layer of the outer wall of the wheel hub can be obtained simultaneously, thereby increasing the service life of the temperature sensor (8) and the airflow insensitive angle range, and having the characteristics of high spatial resolution, high precision and high reliability.

Claims

1. A method for using a full-parameter probe for measuring a two-dimensional steady-state flow field in a hub boundary layer to achieve multi-horizontal flow field parameter measurement, wherein the full-parameter probe structure used is composed of a probe head (1), a probe support rod (2), a pressure sensing left hole (3), a pressure sensing middle hole (4), a pressure sensing right hole (5), a heat-insulating seal (6), an arc groove (7), a temperature sensor (8), a temperature sensing hole (9), a temperature sensor cable lead-out channel (10), a pressure lead-out channel (11), a temperature sensor cable (12) and a pressure lead-out tube (13), and is characterized in that: The probe head (1) is a cylindrical structure. Three mutually unconnected pressure sensing holes are formed on the windward side of the probe head (1), namely a left pressure sensing hole (3), a middle pressure sensing hole (4), and a right pressure sensing hole (5). An arc groove (7) is formed on the leeward side of the probe head (1) directly opposite the middle pressure sensing hole (4). A temperature sensing hole (9) is formed in the arc groove (7). A temperature sensor (8) is placed in the arc groove (7). A heat-insulating seal (6) is located at the opening of the temperature sensing hole (9) and is used to fix the temperature sensor (8). Furthermore, the diameter of the cylindrical body of the probe head (1) is 0.8 mm to 4 mm, and the length is 6 mm to 50 mm. Three mutually unconnected pressure tube lead-out channels (11) and a temperature sensor cable lead-out channel (10) are provided along the axial direction of the probe. The three pressure tube lead-out channels (11) are respectively connected to the pressure sensing left hole (3), the pressure sensing middle hole (4), and the pressure sensing right hole (5), and are respectively connected to three pressure tubes (13) encapsulated in the probe head. The pressure tube (13) is led out of the tail of the probe support rod (2) through the pressure tube lead-out channel (11) in the probe support rod (2), and the temperature sensor cable (12) is led out of the tail of the probe support rod (2) through the temperature sensor cable lead-out channel (10) in the probe support rod (2). The axis of the cylindrical body of the probe head (1) coincides with the axis of the cylindrical body of the probe support rod (2). Furthermore, the pressure sensing middle hole (4) is elliptical and has an inner chamfer of 10° to 60°, a major axis of 0.3 mm to 1.5 mm, a minor axis of 0.15 mm to 0.7 mm, a center line of which is 0.3 mm to 0.7 mm away from the top surface of the probe head (1), and is perpendicular to the axis of the probe head (1) and on the same plane; the pressure sensing left hole (3) and the pressure sensing right hole (5) are circular and symmetrically distributed along the plane, with the same diameter of 0.1 mm to 0.5 mm, a center line of which is 0.6 mm to 1.5 mm away from the top surface of the probe head (1), a center line of the pressure sensing left hole (3) and a center line of the pressure sensing right hole (5) intersecting the axis of the probe head (1), a circumferential surface of which is perpendicular to the axis of the probe head (1), and a circumferential angle on the cylindrical surface of the probe head (1) of 20° to 80°; Furthermore, the arc surface of the arc groove (7) on the leeward side of the probe head (1) is a third of a circle with a diameter of 0.3 mm to 1.5 mm, the axis of the arc groove is parallel to the axis of the probe head (1), and the length along the axis of the probe head (1) is 0.6 mm to 1.4 mm, the temperature sensing hole (9) is circular with a diameter of 0.15 mm to 0.7 mm, the center line of which coincides with the center line of the pressure sensing hole (4), and the distance from the top surface of the probe head (1) is 0.3 mm to 0.7 mm, the temperature sensor (8) is located on the center line of the temperature sensing hole (9), relying on the heat insulation sealing member ( 6) is fixed, and the distance from the axis of the probe head (1) is 0.3 mm to 1.8 mm. Furthermore, the arc surface of the arc groove (7) on the leeward side of the probe head (1) is a third of a circle with a diameter of 0.3 mm to 1.5 mm, the axis of the arc groove (7) is parallel to the axis of the probe head (1), and the length along the axis of the probe head (1) is 0.6 mm to 1.4 mm. The temperature sensing hole (9) is circular, with a diameter of 0.15 mm to 0.7 mm, and its center line coincides with the center line of the pressure sensing hole (4), and the distance from the top surface of the probe head (1) is 0.3 mm to 0.7 mm. The use steps are as follows: Step 1: in a calibration wind tunnel with known incoming flow Mach number and temperature, allow the incoming flow to flow through the probe head; Step 2: Measure the pressure of the pressure sensing hole on the windward side of the probe and the temperature of the temperature sensor on the leeward side under different working conditions; The third step: determine the calibration curves of total temperature and total pressure at different Mach numbers and different deflection angles through data processing based on the data obtained by calibration; the fourth step: when in use, insert the device of the present invention into the measured flow field, perform data processing on the pressure and temperature signals obtained by actual measurement, and realize the measurement of all parameters such as total temperature, static temperature, total pressure, static pressure, deflection angle, Mach number, density and speed in the two-dimensional complex flow field at the inlet, outlet and impeller stage hub side boundary layer of compressors, fans, compressors, etc.

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