CN211668740U - Multi-point dynamic full-parameter measuring device for subsonic two-dimensional flow field - Google Patents

Abstract

The invention belongs to the technical field of flow field testing, and discloses a multi-point dynamic full-parameter measuring device for a subsonic two-dimensional flow field, which comprises a head part, a transition section and a support rod, wherein the head part and the support rod are cylindrical, a total pressure hole and two pressure sensing holes on the windward side of the head part form a three-hole structure, a total temperature hole is formed on the leeward side, the total temperature hole and the total pressure hole are arranged in the opposite directions and are collinear with each other, a plurality of three-hole structures and the total temperature hole are distributed along the axial direction, the central line direction of each total pressure hole is different, a temperature sensor is positioned in the total temperature hole, the front end of the temperature sensor is flush with the cylindrical surface of the head part, pressure sensors are packaged in the total pressure hole and the. The invention can simultaneously realize the multi-point dynamic measurement of all parameters such as total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, speed, density and the like, has high measurement precision of the total temperature and the total pressure, and is used for the multi-point dynamic measurement of the air inlet channel of the aircraft engine and the multi-point dynamic measurement of all parameters between the inlet and the outlet of the impeller machinery and the blade row along the blade height direction.

Description

A multi-point dynamic full-parameter measurement device for subsonic two-dimensional flow field

technical field

The invention relates to the technical field of flow field testing, in particular to a multi-point dynamic full-parameter measurement device for a subsonic two-dimensional flow field, which is used for multi-point full-parameter dynamic measurement of an aero-engine air inlet along one direction and an impeller machinery Full-parameter dynamic measurement of multiple points along the blade height direction between the inlet, outlet and blade rows.

Background technique

The performance experiments of compressors, turbines, pumps, fans, fans, etc. need to measure the distribution of the blade inlet, outlet, and interstage flow field parameters in the flow channel along the blade height direction. The existing probe technology can be implemented in the following ways:

Using a single-point temperature-pressure combination probe requires the probe displacement mechanism to drive the probes to measure at different leaf height positions respectively. The experimental measurement time is long and the experimental cost is high. And the multi-point measurement results in this way are not obtained at the same time. If the dynamic measurement of the unsteady flow field is performed, the results measured at each point cannot be compared, and only steady-state measurement can be achieved.

Since the existing multi-point pressure probes generally can only achieve multi-point total pressure measurement, and cannot achieve simultaneous multi-parameter measurement, therefore, a combination of a single-point three-hole pressure probe and a multi-point total temperature probe can be used to measure To obtain the parameter distribution of each point, the pressure measurement needs to use the probe displacement mechanism to drive the probe to measure separately at different leaf height positions. The experimental measurement time is long, the experimental cost is high, and the measurement results cannot be obtained at the same time, and it is only suitable for stable operation. state measurement. In addition, this kind of measurement needs to ensure that the measuring points of the pressure probe and the total temperature probe are consistent, but on the one hand, due to the existence of installation errors, it is difficult for the measuring points of the probes to be consistent; on the other hand, even if the installation error is not considered Existing, due to the complexity and unsteadiness of the flow in the flow field, the flow conditions at each point of the two measurements are completely different, so it is not suitable for dynamic measurement; in addition, the temperature and pressure are measured separately, the installation process is cumbersome, and it is also not suitable for dynamic measurement. The time cost of the test operation and the difficulty of the test are increased.

The internal profile of the total pressure hole of the existing dynamic pressure probe is generally a straight transition, and the straight transition will cause a certain total pressure loss, resulting in inaccurate measurement results; in addition, the straight transition will lead to flow separation, resulting in flow separation Fluctuations in the total pressure can also interfere with the total pressure measurement.

The existing probes that can measure temperature parameters include a total temperature probe and a combined temperature and pressure probe. According to the existing design concept of the total temperature probe, the key to accurately measuring the total temperature of the airflow is whether the temperature probe can The airflow must be stagnant at the temperature measurement point. Therefore, most of the existing temperature probes are designed according to the requirements of the temperature sensor facing the mainstream. The disadvantages of placing it in the stagnation cover are: first, the temperature sensor is directly washed by the fluid, and is easily affected by oil droplets, dust, etc. contained in the airflow, and is easily damaged; second, usually by increasing the size of the temperature sensor. Increase the strength of the sensor, coupled with the size of the stagnation cover, so the size of the probe is larger, which will make its spatial resolution poor; When the temperature is large, the airflow cannot be fully stagnant; fourth, the heat exchange on the surface of the temperature sensor is insufficient, and the total temperature measurement error is large; at the same time, the single total temperature probe cannot realize the measurement of the full dynamic parameters of the subsonic flow field.

There is also a single temperature and pressure combination probe to measure the temperature and pressure of a single point in the flow field at the same time. The temperature sensors of the existing temperature and pressure combination probes are all facing the mainstream, which has the shortcomings of the above temperature probes, and the temperature and pressure measurement points are measured. are not the same streamline parameters, resulting in poor spatial resolution and measurement errors. Therefore, there are the above problems in temperature measurement, and it is difficult to meet the needs of accurate measurement of two-dimensional dynamic full parameters of subsonic flow fields. Therefore, there is an urgent need for a A multi-point dynamic full-parameter measurement device for subsonic two-dimensional flow field, used for dynamic and accurate multi-point full-parameter measurement along the radial direction of aero-engine air intake, and multi-point full parameters of impeller machinery inlet and outlet and between blade rows along the blade height direction Measurements including total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, velocity and density.

Under external interference, the output of the pressure sensor will have an undesired change that is unrelated to the input, that is, drift. Drift includes zero drift and sensitivity drift. Zero drift or sensitivity drift can be divided into time drift and temperature drift. Time drift refers to the slow change of zero or sensitivity with time under specified conditions, and temperature drift is the drift of zero or sensitivity caused by changes in ambient temperature. Temperature drift is one of the main causes of measurement errors in pressure sensors. The zero-point output voltage of different pressure sensors varies with temperature, and its change trend and change range are different. Therefore, temperature correction for the zero-point drift of a specific pressure sensor is a necessary condition to ensure the accuracy of pressure measurement. However, the existing multi-point measuring probe can only measure the total pressure but cannot measure the parameters of total temperature and static temperature, so the pressure sensor cannot be corrected in time, and the accuracy of the pressure measurement result cannot be guaranteed.

The boundary layer on the inner wall of the casing of the aero-engine inlet, compressor, fan, etc. is affected by the rotation of the rotor, the staggered arrangement of the moving and stationary blade rows, and the interaction between the leakage flow of the blade tip gap and the boundary layer, and the internal flow is very complex. , and the existing probes for measuring parameters in the boundary layer are all steady-state probes, which cannot realize dynamic measurement of all parameters in the boundary layer. At the same time, due to the thin thickness of the boundary layer, pressure probes, temperature probes, and hot-wire anemometers are often used separately to measure the total pressure, temperature, and velocity parameters in the boundary layer. For a single parameter, on the one hand, such a measurement method will cause great interference to the flow field of the thin boundary layer, on the other hand, it will increase the complexity of the test and the cost of the test test. The most important thing is the flow measured by different probes. The parameters cannot be guaranteed to come from the same streamline, so the combination of parameters such as calculation speed will bring additional errors, thereby reducing the accuracy of the experimental test.

The existing multi-point full-parameter dynamic measurement technology has the following deficiencies: 1. When a single-point measurement probe is used for multi-point measurement, the existing single-point measurement probe, whether it is a pressure probe or a temperature-pressure combination probe, has no problem. There are problems that the probe needs to be driven by the probe displacement mechanism to measure separately at different leaf height positions, the experimental measurement time is long, the experimental cost is high, and it cannot be used for dynamic measurement of complex flow fields; 2. The existing multi-point measurement The probe can only achieve steady state measurement of total pressure, and cannot achieve multi-point measurement of all parameters such as total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, speed, density, etc., nor can it achieve dynamic measurement; 3. The internal profile of the total pressure hole of the existing dynamic pressure probe is generally a straight transition, and the straight transition causes a certain total pressure loss, resulting in inaccurate dynamic measurement results; in addition, the straight transition will lead to flow separation, resulting in flow separation The fluctuations of the dynamic total pressure will also cause interference to the dynamic total pressure measurement results; 4. In terms of temperature measurement, the existing total temperature and temperature pressure combination probe has a temperature sensor that is directly flushed by the fluid facing the mainstream, and is susceptible to oil droplets and dust mixed in the airflow. It is easy to be damaged, the size of the probe is large, the spatial resolution is poor, and the airflow insensitivity angle is small. When the deflection angle of the incoming flow to be measured is large, the airflow cannot be fully stagnant, and the surface of the temperature sensor exchanges heat. Insufficient, the total temperature measurement error is relatively large, and at the same time, the single total temperature probe cannot realize the measurement of the dynamic full parameters of the subsonic flow field; 5. The existing multi-point measurement probe can only measure the total pressure but not The total temperature and static temperature parameters are obtained by measurement, so the pressure sensor cannot be corrected in time, and the accuracy of the pressure measurement results cannot be guaranteed. 6. The existing probes for measuring parameters in the boundary layer are steady-state probes, which cannot be In the dynamic measurement of all parameters in the boundary layer, using multiple probes to measure each parameter will cause great interference to the flow field of the thin boundary layer, which increases the complexity of the test and the cost of the test. The flow parameters measured by the needle cannot be guaranteed to come from the same streamline, which reduces the accuracy of the experimental test.

SUMMARY OF THE INVENTION

In view of the above-mentioned deficiencies in the prior art, the present invention provides a multi-point dynamic full-parameter measurement device for subsonic two-dimensional flow field, the purpose is to solve the following problems: The single-point measurement probes in the field of parameter measurement have long measurement time, high experimental cost and cannot be used for complex flow field dynamic measurement when performing multi-point measurement; multi-point measurement probes can only achieve steady-state measurement of total pressure, It cannot realize the correction of the zero temperature drift of the pressure sensor, nor can it realize the multi-point dynamic measurement of all parameters such as total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, speed, density, etc.; the total pressure of the dynamic pressure probe The straight transition of the inner surface of the hole causes a certain total pressure loss, resulting in inaccurate measurement results; in terms of temperature measurement, the existing total temperature and temperature pressure combination probe has a temperature sensor that is directly flushed by the fluid facing the mainstream, and is easily affected by the airflow. Damaged by the influence of oil droplets, dust, etc., large probe size leads to poor spatial resolution, small airflow insensitivity angle leads to insufficient stagnation of airflow, and insufficient heat exchange on the surface of the temperature sensor causes total temperature measurement error Larger; a single total temperature probe cannot realize dynamic full parameter measurement of subsonic flow field; the existing probes for measuring parameters in the boundary layer are steady-state probes, which cannot realize dynamic measurement of all parameters in the boundary layer , the use of multiple probes to measure each parameter will cause great interference to the flow field of the thin boundary layer, which increases the complexity of the test and the cost of the test test. At the same time, the flow parameters measured by different probes cannot be guaranteed to come from The same streamline reduces the accuracy of the test test.

In the present invention, the distribution of the total temperature holes and the total pressure holes are 180° to each other, and the center line is collinear, which abandons the traditional design concept of the total temperature probe. The method to achieve total temperature measurement is designed, but based on the applicant's years of research, the layout and structural design of the temperature sensor placed on the leeward side of the head are creatively proposed. The impact of the air flow on the temperature sensor and the influence of oil droplets and dust mixed in the air flow on the temperature sensor make it possible to use a very small temperature sensor, which improves the service life of the temperature sensor; effectively reduces the size of the head and improves the The spatial resolution of the probe is improved; the convection heat transfer between the airflow and the temperature sensor is strengthened, and the temperature recovery coefficient is high and stable in a large deflection angle range; at the same time, the parameters measured by the temperature sensor and the pressure sensor are the parameters of the same streamline, The zero drift of the used pressure sensor can be temperature corrected to ensure the accuracy of the pressure measurement.

The head of the present invention is provided with a multi-point total temperature hole and a "three-hole structure" for pressure measurement. Both the temperature sensor and the pressure sensor are dynamic sensors, and the device alone can realize the simultaneous dynamic measurement of the total temperature and the pressure at multiple points. All parameters such as total pressure, static temperature, static pressure, Mach number, deflection angle, speed, density, etc., do not need to use the probe displacement mechanism to drive the probe to measure separately at different leaf height positions, saving experimental time, and the head size is small And the top and bottom measuring holes are close to the end, which can be used for the measurement of boundary layer parameters.

Compared with the straight transition section of the existing dynamic total pressure probe, the total pressure hole of the present invention can reduce the total pressure loss and flow separation when converging in a wider deflection angle range, and reduce the The pressure fluctuation caused by the structure of the pressure sensing hole is small, and the accuracy of the total pressure measurement is improved. The total temperature hole adopts a circular truncated hole, which can have a high and stable temperature recovery coefficient in a large deflection angle range, which is conducive to strengthening the airflow and temperature. For the convection heat transfer of the sensor, the front end of the temperature sensor of the present invention is flush with the cylindrical surface of the head, that is, the measuring point where the temperature sensor is located is just on the cylindrical surface of the head, and the flow characteristics around the head can be fully utilized to achieve accurate temperature measurement.

In order to solve the above technical problems, the present invention provides a multi-point dynamic full-parameter measurement device for a subsonic two-dimensional flow field, characterized in that it comprises a head (1), a transition section (2), a strut ( 3), the head (1) and the support rod (3) are both cylindrical, the windward surface of the head (1) is provided with a total pressure hole (7), and the center line of the total pressure hole (7) is perpendicular to the head (1). ) center line, there is a pressure sensing hole (8) on each side of the total pressure hole (7), the total pressure hole (7) and the pressure sensing hole (8) on both sides are at an angle of 15°~16° and the total pressure The center line of the hole (7) and the pressure-sensing holes (8) on both sides are on a plane, forming a three-hole structure, and a total temperature hole (9) is opened on the leeward side of the head (1). The total pressure holes (7) form 180° with each other and the center lines are collinear, the temperature sensor (6) is located in the total temperature hole, and the pressure sensor (11) is packaged in the total pressure hole (7) and the pressure sensing hole (8), respectively, A sensor cable lead-out channel (12) is opened at the head of the device, and the pressure sensor cable (4) and the temperature sensor cable (5) are led out from the rear of the device through the channel;

Further, there are at least 5 above-mentioned three-hole structures and at least 5 total temperature holes (9) distributed along different axial positions of the head (1), the distribution law is uniform distribution, and the axial distance between the centerlines of the adjacent two holes is 0.3 ～0.9mm; or showing the distribution law of sparseness in the middle and dense on both sides, the axial distance between the center line of the first total pressure hole (7) and the second total pressure hole (7) at the top of the head is 0.3～1.1mm, The axial distance between the center line of the first total pressure hole (7) and the second total pressure hole (7) at the bottom of the head is 0.3 to 1.1 mm, and the axial distance between the center lines of the remaining two adjacent holes is 0.5～1.2mm; the axial distance from the centerline of the total pressure hole at the top and bottom of the head to the end is 0.5～1mm. The centerlines of each total pressure hole and the last total pressure hole are parallel;

Further, the total pressure hole (7) adopts a smooth transition of a micro-loss convergent curved surface, and the profile curve of the curved surface satisfies the following equation:

In the formula, R ₂ is the outlet radius, L is the length of the inlet section of the pressure measuring medium hole, R ₁ is the inlet radius, x _m is the coordinate of the connection point between the front and rear sections, and x _m is selected as 0.3.

The diameter of the inlet of the micro-loss convergent surface is 0.2-0.5mm, the diameter of the outlet of the micro-loss convergent surface is 0.1-0.25mm, the outlet of the micro-loss convergent surface is connected to the sensor cable lead-out channel (12), the diameter of the pressure sensing hole is 0.1-0.2mm, the pressure The sensing hole is communicated with the sensor cable lead-out channel (12);

Further, the total temperature hole (9) is a truncated truncated hole opened on the cylindrical surface of the head, the diameter at the entrance of the hole is 0.4-0.8 mm, the diameter at the exit is 0.5-0.6 times the diameter at the entrance, and the diameter at the exit of the hole is 0.4-0.8 mm. The sensor cable lead-out channel (12) is connected;

Further, the front end of the temperature sensor (6) is flush with the cylindrical surface of the head, and is fixed in the temperature measurement hole by using a thermal insulation seal (10), and the front end of the pressure sensor in the total pressure hole (7) converges with the micro-loss. The outlet of the curved surface is flush, the distance between the pressure sensor in the pressure sensing hole and the inlet of the pressure sensing hole is 0.5-1.5 mm, and the temperature sensor cable and the pressure sensor cable are led out through the sensor cable lead-out channel (12) inside the probe;

Further, the diameter of the head (1) is 2-6 mm, and the diameter of the sensor cable lead-out channel (12) is 0.5-0.6 times the diameter of the head (1);

Further, the temperature sensor (6) can be a thermal resistance, a thermocouple or an optical fiber temperature sensor;

Further, after wind tunnel calibration, calibration and data processing, a multi-point dynamic full-parameter measurement device for subsonic two-dimensional flow field of the present invention can simultaneously realize multi-point dynamic full-parameter measurement, including total temperature and total pressure. , static temperature, static pressure, Mach number, deflection angle, speed, density, and has high measurement accuracy of total temperature and total pressure.

The advantages and positive effects of the present invention are:

Beneficial effect 1: Compared with the prior art, the temperature sensor of the present invention faces away from the mainstream and is located in the low-speed separation area on the leeward side of the head, firstly reducing the scouring of the temperature sensor by the airflow, and simultaneously reducing the oil droplets mixed in the airflow, The impact of dust on the temperature sensor effectively improves the service life of the temperature sensor; secondly, the strength requirements of the temperature sensor are lower, and the size of the temperature sensor can be smaller, which effectively reduces the size of the head, plus the total temperature The back arrangement of the orifice and the total pressure hole can make full use of the space and is also conducive to reducing the size of the head. Therefore, its spatial resolution is high; third, the range of the separation low-velocity area is large, and the vortex in the separation area is effectively strengthened. The heat exchange between the airflow and the temperature sensor, so the temperature recovery coefficient is high and stable in a large deflection angle range during measurement; fourth, the temperature sensor is placed in the flow field, and there is no obstruction between the flow field and its response time is fast; Fifth, the front end of the temperature sensor of the present invention is flush with the cylindrical surface of the head, that is, the measuring point where the temperature sensor is located is just on the cylindrical surface of the head, which can make full use of the flow characteristics around the head to achieve accurate temperature measurement.

Beneficial effect 2: The head of the present invention is provided with a multi-point total temperature hole and a "three-hole structure" for pressure measurement. The total temperature measured and the total pressure measured by the total pressure hole are in the same streamline. Both the temperature sensor and the pressure sensor use dynamic sensors. Therefore, the total temperature, total pressure, static temperature, static pressure and Mach number can be realized by using this device alone. Multi-point synchronous dynamic measurement of all parameters such as deflection angle, velocity, density, etc. For multi-point full-parameter measurement of complex unsteady flow fields, it is not necessary to install temperature probes and pressure probes separately to achieve full-parameter measurement, nor to use probes. The needle displacement mechanism drives the probe to measure separately at different leaf height positions, saving experimental time.

Beneficial effect 3: The total pressure hole of the present invention adopts a smooth transition of the micro-loss convergent surface. Compared with the straight transition section of the existing dynamic total pressure probe, the total pressure loss and Flow separation improves the accuracy of total pressure measurement. The total temperature hole adopts a circular truncated hole, which can have a high and stable temperature recovery coefficient in a large deflection angle range, which is conducive to strengthening the convective heat transfer between the airflow and the temperature sensor.

Beneficial effect 4: Temperature drift is one of the main reasons for the measurement error of the pressure sensor. The zero-point output voltage of different pressure sensors varies with temperature and its variation trend and variation range are different. The device of the present invention can measure the total temperature and static temperature parameters. , and the total temperature hole and the total pressure hole form a 180° distribution with each other and the center line is collinear, the parameters measured by the temperature sensor and the pressure sensor are parameters of the same streamline, and the zero drift of the used pressure sensor can be temperature corrected. The accuracy of pressure measurement is guaranteed.

Beneficial effect five: The size of the head of the present invention can be very small, so it can also be used for the measurement of the parameters of the boundary layer, and because the present invention can simultaneously realize the total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, speed, density Dynamic measurement of equal full parameters and high measurement accuracy of total temperature and total pressure, therefore, when using the present invention to measure the parameters of the boundary layer, it is not necessary to use multiple probes to measure the full parameters of the flow field for many times, reducing the comparison and comparison. The interference of the thin boundary layer; the present invention realizes the dynamic measurement of the full parameters of the boundary layer. Therefore, it is suitable for the boundary layer with complicated flow caused by the rotor rotation, the staggered arrangement of the moving and stationary blade rows, and the leakage flow of the blade tip clearance. Dynamic full parameter measurement can be achieved.

The present invention has the following advantages: the device of the present invention can be used alone to realize the measurement of multi-point dynamic full parameters, including total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, speed, density, and has a high Total temperature, total pressure measurement accuracy.

Description of drawings

FIG. 1 is a front view of the structure of a first embodiment of the probe of the present invention.

FIG. 2 is a cross-sectional view of the rear view of the structure of the first embodiment of the probe of the present invention.

FIG. 3 is a partial enlarged view of the total pressure hole and total temperature hole structure of the first structure of the probe according to the present invention.

FIG. 4 is a schematic cross-sectional view of A-A of the structure of the probe according to the first embodiment of the present invention.

FIG. 5 is a definition diagram of the total pressure hole profile curve in the first embodiment of the probe of the present invention.

FIG. 6 is a schematic diagram of the installation of the device in the first embodiment of the present invention.

FIG. 7 is a front view of the structure of the second embodiment of the probe of the present invention.

8 is a rear cross-sectional view of the structure of the second embodiment of the probe of the present invention.

FIG. 9 is a partial enlarged view of the total pressure pore and total temperature pore structure of the second structure of the probe according to the present invention.

FIG. 10 is a schematic cross-sectional view of A-A of the structure of the second embodiment of the probe of the present invention.

Fig. 11 is a definition diagram of the total pressure hole profile curve in the second embodiment of the probe of the present invention.

FIG. 12 is a schematic diagram of the installation of the device in the second embodiment of the present invention.

Marks and corresponding parts and surface names in the drawings: including 1-head; 2-transition section; 3-strut; 4-pressure sensor cable; 5-temperature sensor cable; 6-temperature sensor; 7-total Pressure hole; 8-pressure sensing hole; 9-total temperature hole; 10-thermal insulation seal; 11-pressure sensor; 12-sensor cable lead-out channel.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings and embodiments, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, and the protection scope of the present invention can be more clearly defined.

The present invention can be applied to the dynamic measurement of full parameters at multiple points along the radial direction of the engine inlet. At this time, the measuring points can be selected to be evenly distributed. When the engine inlet is installed, due to the small limitation of installation space and the strength of the probe, a smaller size can be selected. Large probe structure. The selected structure scheme is as follows:

Example 1:

As shown in Figure 1, Figure 2, Figure 3, Figure 4, this embodiment introduces a multi-point dynamic full-parameter measurement device for a subsonic two-dimensional flow field, including a head (1), a transition section (2) ), the support rod (3), the head (1) and the support rod (3) are cylindrical, the head (1) is provided with a total pressure hole (7) on the windward surface, and the center line of the total pressure hole (7) is vertical On the center line of the head (1), there is a pressure sensing hole (8) on both sides of the total pressure hole (7), and the total pressure hole (7) and the pressure sensing holes (8) on both sides are at an included angle of 15° and The center line of the total pressure hole (7) and the pressure sensing holes (8) on both sides are on a plane, forming a three-hole structure, and a total temperature hole (9) is opened on the leeward side of the head (1), and the total temperature hole (9) ) and the total pressure hole (7) are 180° to each other and the center line is collinear, the temperature sensor (6) is located in the total temperature hole, and the pressure sensor (11) is packaged in the total pressure hole (7) and the pressure sensing hole (8). ), a sensor cable lead-out channel (12) is opened at the head of the device, and the pressure sensor cable (4) and the temperature sensor cable (5) are led out from the rear of the device through this channel;

In this embodiment, the five above-mentioned three-hole structures and five total temperature holes (9) are distributed along different axial positions of the head (1), the distribution law is uniform distribution, and the axial distance between the center lines of two adjacent holes is 0.4 mm, the axial distance from the center line of the total pressure hole at the top and bottom of the head to the end is 0.5mm. The direction of the center line of each total pressure hole is not the same, and is distributed in the range of 180°. The first total pressure hole parallel to the centerline of the last total pressure hole;

The total pressure hole (7) adopts a smooth transition of a micro-loss convergent curved surface. Figure 5 is a definition diagram of the profile curve, and the profile curve of the curved surface satisfies the following equation:

In the formula, R ₂ is the outlet radius, L is the length of the inlet section of the pressure measuring medium hole, R ₁ is the inlet radius, x _m is the coordinate of the connection point between the front and rear sections, and x _m is selected as 0.3.

The diameter of the inlet of the micro-loss convergent surface is 0.3mm, the diameter of the outlet of the micro-loss convergent surface is 0.15mm, the outlet of the micro-loss convergent surface is connected to the sensor cable lead-out channel (12), the diameter of the pressure sensing hole is 0.15mm, and the pressure sensing hole is connected to the sensor cable. The outlet channel (12) is connected;

The total temperature hole (9) is a truncated cone-shaped hole opened on the cylindrical surface of the head. The diameter of the hole at the entrance is 0.5 mm, and the diameter at the exit is 0.5 times the diameter of the entrance. The hole exit and the sensor cable lead-out channel ( 12) Connected;

The front end of the temperature sensor (6) is flush with the cylindrical surface of the head, and is fixed in the temperature measurement hole by using a thermal insulation seal (10). Flush, the distance between the pressure sensor in the pressure sensing hole and the inlet of the pressure sensing hole is 1mm, and the temperature sensor cable and the pressure sensor cable are led out through the sensor cable lead-out channel (12) inside the probe;

In this embodiment, the diameter of the head (1) is 4 mm, and the diameter of the sensor cable lead-out channel (12) is 0.5 times the diameter of the head (1);

In this embodiment, the temperature sensor (6) may be a thermal resistance, a thermocouple or an optical fiber temperature sensor.

Embodiment 2:

The invention can be applied to the dynamic measurement of the total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, speed, density and other parameters at multiple points along the blade height direction between the compressor stages. The direction of the airflow direction varies greatly, and the deflection angle of the local airflow will exceed the insensitive angle measured by the probe, resulting in a larger measurement error. At the tip and root of the blade, near the boundary layer, the total pressure gradient is very large, so it is necessary to select the total pressure gradient. The distribution mode of dense and sparse on both sides of the pressing hole. The diameter of the head should also be smaller. On the one hand, it is convenient to install in the narrow area between the blade rows, and on the other hand, it also minimizes the impact on the boundary layer. The selected probe structure scheme is as follows:

As shown in Fig. 6, Fig. 7, Fig. 8, Fig. 9, this embodiment introduces a multi-point dynamic full-parameter measurement device for a subsonic two-dimensional flow field, including a head (1), a transition section (2) ), the support rod (3), the head (1) and the support rod (3) are cylindrical, the head (1) is provided with a total pressure hole (7) on the windward surface, and the center line of the total pressure hole (7) is vertical On the center line of the head (1), there is a pressure sensing hole (8) on both sides of the total pressure hole (7), and the total pressure hole (7) and the pressure sensing holes (8) on both sides are at an included angle of 15° and The center line of the total pressure hole (7) and the pressure sensing holes (8) on both sides are on a plane, forming a three-hole structure, and a total temperature hole (9) is opened on the leeward side of the head (1), and the total temperature hole (9) ) and the total pressure hole (7) are 180° to each other and the center line is collinear, the temperature sensor (6) is located in the total temperature hole, and the pressure sensor (11) is packaged in the total pressure hole (7) and the pressure sensing hole (8). ), a sensor cable lead-out channel (12) is opened at the head of the device, and the pressure sensor cable (4) and the temperature sensor cable (5) are led out from the rear of the device through this channel;

In this embodiment, the five above-mentioned three-hole structures and the five total temperature holes (9) are distributed along different axial positions of the head (1), showing the distribution law of sparseness in the middle and denseness on both sides, and the first total pressure hole at the top of the head The axial distance between (7) and the center line of the second total pressure hole (7) is 0.3mm, and the distance between the center line of the first total pressure hole (7) and the second total pressure hole (7) at the bottom of the head is 0.3 mm. The axial distance between them is 0.3mm, and the axial distance between the centerlines of the other two adjacent holes is 0.5mm; the axial distance from the centerline to the end of the total pressure hole at the top and bottom of the head is 0.5mm, The direction of the center line of the total pressure holes is not the same, distributed in the range of 180°, the center lines of the first total pressure hole and the last total pressure hole are parallel;

The total pressure hole (7) adopts a smooth transition of a micro-loss convergent curved surface. Figure 10 is a definition diagram of the profile curve. The profile curve of the curved surface satisfies the following equation:

In the formula, R ₂ is the outlet radius, L is the length of the inlet section of the pressure measuring medium hole, R ₁ is the inlet radius, x _m is the coordinate of the connection point between the front and rear sections, and x _m is selected as 0.3.

The diameter of the inlet of the micro-loss convergent surface is 0.2mm, the diameter of the outlet of the micro-loss convergent surface is 0.1mm, and the outlet of the micro-loss convergent surface is connected to the sensor cable outlet channel (12), the diameter of the pressure sensing hole is 0.1mm, and the pressure sensing hole is connected to the sensor cable. The outlet channel (12) is connected;

The total temperature hole (9) is a truncated cone-shaped hole opened on the cylindrical surface of the head. The diameter at the entrance of the hole is 0.4 mm, the diameter at the exit is 0.5 times the diameter at the entrance, and the exit of the hole and the sensor cable lead-out channel ( 12) Connected;

The front end of the temperature sensor (6) is flush with the cylindrical surface of the head, and is fixed in the temperature measurement hole by using a thermal insulation seal (10). Flush, the distance between the pressure sensor in the pressure sensing hole and the inlet of the pressure sensing hole is 0.5mm, and the temperature sensor cable and the pressure sensor cable are led out through the sensor cable lead-out channel (12) inside the probe;

In this embodiment, the diameter of the head (1) is 2 mm, and the diameter of the sensor cable lead-out channel (12) is 0.5 times the diameter of the head (1);

In this embodiment, the temperature sensor (6) may be a thermal resistance, a thermocouple or an optical fiber temperature sensor.

While preferred embodiments have been described, various changes or substitutions may be made in the embodiments without departing from the spirit and scope of the present invention. Accordingly, it is to be understood that the present invention has been described by way of example and not limitation.

Claims (1)

1. a multi-point dynamic full-parameter measuring device for subsonic two-dimensional flow field, is characterized in that, comprises head (1), transition section (2), strut (3), head (1) and The struts (3) are all cylindrical, the windward surface of the head (1) is provided with a total pressure hole (7), the center line of the total pressure hole (7) is perpendicular to the center line of the head (1), and the total pressure hole (7) ) has a pressure sensing hole (8) on each side, the total pressure hole (7) and the pressure sensing holes (8) on both sides are at an angle of 15° to 16°, and the total pressure hole (7) and the pressure on both sides of the total pressure hole (7) The center line of the sensing hole (8) is on a plane, forming a three-hole structure, and a total temperature hole (9) is opened on the leeward side of the head (1). ° and the center lines are collinear, the temperature sensor (6) is located in the total temperature hole, the pressure sensor (11) is encapsulated in the total pressure hole (7) and the pressure sensing hole (8) respectively, and the sensor cable is led out from the head of the device a channel (12) through which the pressure sensor cable (4) and the temperature sensor cable (5) are led out from the rear of the device; At least five of the above three-hole structures and five total temperature holes (9) are distributed along different axial positions of the head (1). ; or the distribution law is dense in the middle and dense on both sides, the axial distance between the center line of the first total pressure hole (7) and the second total pressure hole (7) at the top of the head is 0.3-1.1mm, and the bottom of the head is 0.3-1.1mm. The axial distance between the center lines of the first total pressure hole (7) and the second total pressure hole (7) is 0.3 to 1.1 mm, and the axial distance between the center lines of the other two adjacent holes is 0.5 to 1.2 mm mm; the axial distance from the center line of the total pressure hole at the top and bottom of the head to the end is taken as 0.5 to 1 mm. The hole is parallel to the centerline of the last total pressure hole; The total pressure hole (7) adopts a micro-loss convergent surface for smooth transition, and the profile curve of the surface satisfies the following equation:

In the formula, R ₂ is the outlet radius, L is the length of the inlet section of the pressure measuring hole, R ₁ is the inlet radius, x _m is the coordinate of the connection point between the front and rear sections, and x _m is selected as 0.3; The diameter of the inlet of the micro-loss convergent surface is 0.2-0.5mm, the diameter of the outlet of the micro-loss convergent surface is 0.1-0.25mm, the outlet of the micro-loss convergent surface is connected to the sensor cable lead-out channel (12), the diameter of the pressure sensing hole is 0.1-0.2mm, the pressure The sensing hole is communicated with the sensor cable lead-out channel (12); The total temperature hole (9) is a truncated cone-shaped hole opened on the cylindrical surface of the head, the diameter of the hole at the entrance is 0.4-0.8mm, the diameter of the exit is 0.5-0.6 times the diameter of the entrance, and the exit of the hole is connected to the sensor line. The cable outlet channel (12) is connected; The front end of the temperature sensor (6) is flush with the cylindrical surface of the head, and is fixed in the temperature measurement hole by using a thermal insulation seal (10). Flush, the distance between the pressure sensor in the pressure sensing hole and the inlet of the pressure sensing hole is 0.5-1.5 mm, and the temperature sensor cable and the pressure sensor cable are led out through the sensor cable lead-out channel (12) inside the probe; The diameter of the head (1) is 2-6 mm, and the diameter of the sensor cable lead-out channel (12) is 0.5-0.6 times the diameter of the head (1); The temperature sensor (6) can be a thermal resistance, a thermocouple or an optical fiber temperature sensor; The probe is calibrated through the calibration wind tunnel to obtain the probe calibration curve; in the actual measurement, based on the data measured by the three pressure sensors and temperature sensors at each axial position, and then the calibration coefficient curve obtained by calibrating the calibration wind tunnel and formula, through data processing, the multi-point dynamic parameters of the measured subsonic two-dimensional flow field can be obtained at the same time, including total temperature, total pressure, static temperature, static pressure, Mach number, deflection angle, velocity, density parameters and have High total temperature and total pressure measurement accuracy.

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