A three-hole pressure probe suitable for wide range of turbine stage measurement

Abstract

The present application belongs to the technical field of internal flow pressure test, and particularly relates to a three-hole pressure probe suitable for wide measurement range between turbine stages. The head support rod is welded with the probe support rod; the probe head is located at the front end of the head support rod, and is provided with a pressure measuring middle hole, a pressure measuring left hole and a pressure measuring right hole which are not communicated with each other; the pressure lead pipe is packaged in the probe support rod, one end of which is communicated with the three pressure measuring holes of the probe head, and the other end is led out from the tail of the probe support rod through the pressure lead pipe channel. The present application reduces the interference of the three-hole pressure probe to the measured flow field in the high Mach number range through the innovative structure design of the probe head and the head support rod, so that the high precision measurement in the wide Mach number range can be realized by inserting the probe into the narrow space between the turbine stages. The present application proposes two new data processing methods of the three-hole pressure probe, effectively expands the angle measurement range of the probe, and realizes the measurement in the wide airflow angle range between the turbine stages.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of internal flow pressure test, and particularly relates to a three-hole pressure probe suitable for wide measurement range of turbine interstage, and suitable for measurement of two-dimensional flow field of engine turbine interstage. BACKGROUND

[0002] In order to obtain the performance parameters of the turbine components in the engine and the flow field structure inside the turbine components, pressure measurement needs to be performed on the interstage. At present, the commonly used measurement means in engineering application is to realize through a contact type pressure probe. The three-hole pressure probe is widely used in the measurement of two-dimensional flow field due to its small size and simple structure.

[0003] However, the distance between the turbine components in the engine is small, and the space structure is compact, which greatly limits the size of the probe and also puts high requirements on the structural design of the probe. If the straight probe head structure shown in Fig. Figure 12 a (Exploration of three-hole probe test in large separation zone, Experimental and Measurement in Fluid Mechanics) is used, the measurement of the airflow perpendicular to the probe direction cannot be realized when the turbine interstage is measured; if the structure of directly opening holes on the side of the probe head shown in Fig. Figure 12 b (Invention patent: three-hole transonic pressure probe, 201510730721.2) is used, the probe head will form stagnation to the airflow, affecting the accuracy of the probe measurement; the "L" type head structure shown in Fig. Figure 12 c can avoid the influence of the head on the measurement, but the "L" type protruding part is too long to be inserted into the narrow space of the turbine interstage to complete the measurement. In addition, the size of the probe is too large to cause serious disturbance to the flow field environment to be measured, affecting the accuracy of the measurement. With the continuous optimization of the turbine components, the internal airflow velocity is continuously improved, and the speed can reach high subsonic or even supersonic. The measured flow field has a very wide Mach number range, and the damage of the probe to the flow field itself will be more serious, which also brings greater challenges to the aerodynamic design, geometric size and structural design of the probe.

[0004] With the pursuit of high performance of modern engines, the turbine blade is mostly designed with swept-back shape, and the blade curvature changes greatly, which means that the angle of airflow will also change greatly after passing through the first blade, and the angle difference is greater in different blade height directions, which can reach ±60° or higher changes. The deflection angle range measured by the conventional three-hole probe is about ±30°, which is difficult to meet the measurement requirements in the complex internal flow environment between turbine stages. Although the three-hole probe can measure the flow field structure with large angle change of airflow by means of self-rotation of the three-hole probe at different blade height positions through the displacement mechanism, it is difficult to install the displacement mechanism on some small and compact turbine testers. In addition, rotating to cover the wide measurement range of airflow angle will make the test time doubled and introduce many unnecessary test errors.

[0005] The three-hole pressure probe has problems in size, structure and angle measurement range, which seriously restricts the test tasks and scientific research of engine turbine components. Therefore, there is an urgent need for a three-hole pressure probe suitable for wide measurement range between turbine stages for measuring two-dimensional flow field parameters between super turbine stages. SUMMARY

[0006] In view of the problem that the existing three-hole pressure probe is difficult to meet the wide range measurement requirement between turbine stages, the present application provides a three-hole pressure probe suitable for wide measurement range between turbine stages. First, the innovative probe head and head support rod structure design is used to realize high-precision measurement of wide Mach number flow field between turbine stages. Then two new three-hole pressure probe data processing methods are proposed to realize the measurement of wide deflection angle change range between turbine stages. The present application provides a new type of three-hole pressure probe structure, overcomes the shortcomings of the traditional three-hole pressure probe aerodynamic calibration method, creatively expands the measurement angle range of the three-hole pressure probe to ±80°, and can be applied to the measurement of inter-stage flow field in the range of 0.1-1.4 Mach number, which makes up for the deficiency of the traditional three-hole pressure probe in the measurement under this test environment.

[0007] The technical scheme of the present application is:

[0008] 1. A three-hole pressure probe suitable for wide measurement range between turbine stages, comprising a probe support rod (1), a probe head (2), a head support rod (3), a pressure measuring middle hole (4), a pressure measuring left hole (5), a pressure measuring right hole (6), a pressure pipe passage (7), and a pressure pipe (8), characterized in that:

[0009] The head support rod (3) is welded with the probe support rod (1); the probe head (2) is located at the front end of the head support rod (3), and the pressure measuring middle hole (4), the pressure measuring left hole (5) and the pressure measuring right hole (6) which are not communicated with each other are arranged; the pressure guide pipe (8) is encapsulated in the probe support rod (1), one end of which is communicated with the three pressure measuring holes of the probe head (2), and the other end is led out from the tail of the probe support rod (1) through the pressure guide pipe channel (7).

[0010] 2. Further, the probe support rod (1) is a cylinder, and the cross-sectional diameter is 3-30 mm.

[0011] 3. Further, the head support rod (3) is in the shape of a "L" as a whole, and a circular arc is arranged at the middle corner, the cross section of the head support rod (3) is a triangle, the top angle is opposite to the flow direction, the included angle is 30-120°, the length of the bottom side is 0.6-5 mm, and the three edges are polished or kept as sharp angles.

[0012] The side surface of the head support rod (3) is used as a horizontal positioning surface of the probe.

[0013] 4. Further, the size of the head support rod (3) in the direction of the top does not exceed the cross section of the probe support rod (1), the distance between the size of the head support rod (3) and the outer edge of the cross section of the probe support rod (1) is 0.5-1 mm, and the distance between the center axis of the probe head (2) and the connecting surface of the head support rod (3) and the probe support rod (1) is 2-6 times the length of the bottom side of the probe support rod (1).

[0014] 5. Further, the probe head (2) is in the shape of a sharp wedge, the included angle is 30-120°, the pressure measuring middle hole (4), the pressure measuring left hole (5) and the pressure measuring right hole (6) are arranged in the shape of "1", the center axis of the pressure measuring middle hole (4) is opposite to the flow direction, the height of the probe head (2) is 0.4-2 mm, and the width is 0.8-4 mm.

[0015] 6. Further, a three-hole pressure probe suitable for wide measurement range between turbine stages is calibrated in a calibration wind tunnel, the calibration speed range is 0.1-1.4 Mach, and the deflection angle range is -80°-80°.

[0016] 7. Further, the calibration curves of the deflection angle coefficient-deflection angle, the deflection angle-total pressure coefficient and the deflection angle-static pressure coefficient at each Mach number and different deflection angles are obtained through a wide range three-hole probe data processing method, and the wide range three-hole probe data processing method comprises the following three methods.

[0017] 7. Further, the calibration curves of the deflection angle coefficient-deflection angle, the deflection angle-total pressure coefficient and the deflection angle-static pressure coefficient at each Mach number and different deflection angles are obtained through a wide range three-hole probe data processing method, and the wide range three-hole probe data processing method comprises the following three methods.

[0018] The first method is a two-domain method, and the method is characterized by the following steps.

[0019] Step 1: the definitions of the deflection angle coefficient, the total pressure coefficient and the static pressure coefficient are as follows:

[0020] Deflection angle coefficient:

[0021]

[0022] Total pressure coefficient:

[0023]

[0024] Static pressure coefficient:

[0025]

[0026] Wherein: C py is the deflection angle coefficient, C pt is the total pressure coefficient, C ps is the static pressure coefficient, the total pressure and static pressure of the incoming flow of the calibration wind tunnel are P t and P s , the pressure values measured by the middle hole, left hole and right hole of the three-hole pressure probe are P1, P2 and P3 respectively.

[0027] Step two: obtain the calibration curves of the deflection angle-deflection angle coefficient, deflection angle-total pressure coefficient and deflection angle-static pressure coefficient at different deflection angles of each incoming flow Mach number through the calculation defined in step one, and divide the calibration curves at the point where the left hole pressure value and the right hole pressure value are equal into two domains.

[0028] Step three: when actually measuring, the deflection angle coefficient is calculated by using the measured pressure values of the three holes, and then the size of the left hole pressure value and the right hole pressure value is compared to determine the domain corresponding to the selected deflection angle coefficient-deflection angle calibration curve for interpolation calculation of the initial value of the deflection angle:

[0029] When the left hole pressure value is equal to the right hole pressure value, the deflection angle is 0°;

[0030] When the left hole pressure value is greater than the right hole pressure value, the left domain of the calibration curve is selected;

[0031] When the right hole pressure value is greater than the left hole pressure value, the right domain of the calibration curve is selected.

[0032] Step four: using the obtained initial value of the deflection angle, the initial value of the total pressure, the initial value of the static pressure and the initial value of the Mach number are calculated by interpolation according to the deflection angle-total pressure coefficient and deflection angle-static pressure coefficient calibration curves.

[0033] Step five: according to the initial value of the Mach number, the calibration curves at different Mach numbers are iterated to finally obtain the deflection angle, total pressure, static pressure and Mach number of the measured flow field.

[0034] The second method is a three-domain method, characterized in that:

[0035] Step one: the definitions of the deflection angle coefficient, the total pressure coefficient and the static pressure coefficient are as follows:

[0036] Deflection angle coefficient:

[0037]

[0038] Total pressure coefficient:

[0039]

[0040] Static pressure coefficient:

[0041]

[0042] Wherein: C py is the deflection angle coefficient, C pt is the total pressure coefficient, C ps is the static pressure coefficient, the total pressure and static pressure of the incoming flow of the calibration wind tunnel are P t and P s , the pressure values measured by the middle hole, left hole and right hole of the three-hole pressure probe are P1, P2 and P3 respectively.

[0043] Step two: obtain the calibration curves of the deflection angle-deflection angle coefficient, deflection angle-total pressure coefficient and deflection angle-static pressure coefficient at different deflection angles of each incoming Mach number through the calculation defined in step one, and divide the calibration curves into three domains at the points where the left hole pressure value is equal to the middle hole pressure value and the right hole pressure value is equal to the middle hole pressure value.

[0044] Step three: when actually measuring, the deflection angle coefficient is calculated by using the measured pressure values of the three holes, and then the positive and negative of the deflection angle coefficient and the size of the left and right hole pressure values are compared to determine the domain corresponding to the deflection angle coefficient-deflection angle calibration curve to be selected for interpolation to calculate the initial value of the deflection angle:

[0045] When the left and right hole pressure values are equal, the deflection angle is 0°;

[0046] When the left hole pressure value is greater than the right hole pressure value and the deflection angle coefficient is negative, the right domain of the calibration curve is selected;

[0047] When the left hole pressure value is greater than the right hole pressure value and the deflection angle coefficient is positive, the middle domain of the calibration curve is selected;

[0048] When the left hole pressure value is less than the right hole pressure value and the deflection angle coefficient is negative, the middle domain of the calibration curve is selected;

[0049] When the left hole pressure value is less than the right hole pressure value and the deflection angle coefficient is positive, the left domain of the calibration curve is selected.

[0050] Step four: using the obtained initial value of the deflection angle, the initial value of the total pressure, the initial value of the static pressure and the initial value of the Mach number are calculated by interpolation according to the deflection angle-total pressure coefficient and deflection angle-static pressure coefficient calibration curves.

[0051] Step five: according to the Mach number initial value, the calibration curves under different Mach numbers are iterated, and finally the airflow deflection angle, total pressure, static pressure and Mach number of the measured flow field are obtained.

[0052] The third method is a combination method, characterized in that:

[0053] Step one: the calibration data is divided into three domains according to different deflection angle ranges, which are:

[0054] Left domain: -80°-10°

[0055] Middle domain: -30°-30°

[0056] Right domain: 10°-80°

[0057] Step two: the deflection angle coefficient, total pressure coefficient and static pressure coefficient of each domain are defined as follows:

[0058] Left domain and right domain:

[0059]

[0060] Middle domain:

[0061]

[0062] Wherein: C py is the deflection angle coefficient, C pt is the total pressure coefficient, and C ps is the static pressure coefficient, the total pressure and static pressure of the calibration wind tunnel are P t and P s , the pressure values measured by the middle hole, left hole and right hole of the three-hole pressure probe are P1, P2 and P3, respectively.

[0063] Step three: through the definition in step two, the deflection angle-deflection angle coefficient, deflection angle-total pressure coefficient and deflection angle-static pressure coefficient calibration curves of each domain under each incoming flow Mach number are obtained respectively;

[0064] Step four: during actual measurement, according to the three pressure hole data obtained by wide range calibration, compare the pressure values of each hole, select the corresponding domain according to the direction of the hole with the maximum pressure value, calculate the deflection angle coefficient according to the definition of the deflection angle coefficient of the domain, and then interpolate the deflection angle-deflection angle coefficient calibration curve of the domain to calculate the deflection angle initial value.

[0065] Step five: use the deflection angle initial value obtained, and according to the deflection angle-total pressure coefficient and deflection angle-static pressure coefficient calibration curves of the domain, interpolate to calculate the total pressure initial value, static pressure initial value and Mach number initial value.

[0066] Step six: according to the Mach number initial value, the calibration curve of the domain under different Mach numbers is iterated, and finally the airflow deflection angle, total pressure, static pressure and Mach number of the measured flow field are obtained.

[0067] The beneficial effects of the present application are:

[0068] Compared with the existing three-hole pressure probe, the three-hole pressure probe suitable for wide measurement range between turbine stages can achieve the following beneficial effects:

[0069] Beneficial effect one: the probe head support rod in the present application adopts a triangular design, and the probe head adopts a sharp wedge shape design, which can effectively reduce the interference and blocking effect of the head support rod on supersonic airflow, so that it can be applied to the test of flow field in a wide Mach number range between turbine stages.

[0070] Beneficial effect two: the design that the three-hole probe head support rod does not project beyond the probe support rod section in the top direction can facilitate insertion into the narrow space between turbine stages for testing; the head support rod as a whole is in the shape of a "L", and the middle corner is transitioned with a circular arc, which can make the probe head as far away from the head support rod and the probe support rod as possible, effectively reducing the influence of the head support rod and the probe support rod on measurement accuracy.

[0071] Beneficial effect three: the present application proposes three new three-hole probe data processing methods, which can make the airflow direction range measured by the three-hole pressure probe reach ±80°, and make it better applied to the test and research of wide airflow angle range between turbine stages.

[0072] Beneficial effect four: the combination method in the three-hole probe data processing method of the present application can effectively reduce the measurement error of the interface area of each domain, so that the three-hole pressure probe can realize accurate measurement of airflow parameters in the full range of ±80°. BRIEF DESCRIPTION OF DRAWINGS

[0073] Figure 1 is a structural schematic view of a three-hole pressure probe suitable for wide measurement range between turbine stages in the first embodiment of the present application.

[0074] Figure 2 is Figure 1 the left view

[0075] Figure 3 is Figure 2 the partial enlarged view.

[0076] Figure 4 is Figure 1 the A cross-sectional view of

[0077] Figure 5 is Figure 1 the B cross-sectional view of

[0078] Figure 6 is a top view of Figure 1 .

[0079] Wherein: 1-probe support rod, 2-probe head, 3-head support rod, 4-pressure measuring middle hole, 5-pressure measuring left hole, 6-pressure measuring right hole, 7-pressure lead pipe channel, 8-pressure lead pipe.

[0080] Figure 7 is the installation schematic diagram of the embodiment one of the present application.

[0081] Wherein: 1-casing wall surface, 2-first stage rotor, 3-first stage stator, 4-second stage rotor, 5-second stage stator, 6-third stage rotor, 7-third stage stator, 8-hub wall surface, 9-three-hole probe of the present application for wide range measurement between turbine stages.

[0082] Figure 8 is a partial enlarged view of Figure 7 .

[0083] Figure 9 is the three-domain method calibration curve in the embodiment one of the present application.

[0084] Wherein: C py is a deflection angle coefficient, C pt is a total pressure coefficient, C ps is a static pressure coefficient.

[0085] Figure 10 is the combined method calibration curve in the embodiment one of the present application.

[0086] Figure 11 is the pressure maximum hole distribution diagram in the embodiment one of the present application.

[0087] Figure 12 is the structural schematic diagram of the prior art. DETAILED DESCRIPTION

[0088] The preferred embodiments of the present application are described in detail below with reference to the accompanying drawings, so that the advantages and features of the present application can be more easily understood by those skilled in the art, and the protection scope of the present application is more clearly and definitely defined.

[0089] Embodiment one:

[0090] For the measurement of supersonic two-dimensional flow field between turbine stages, the measurement space is narrow, the inflow angle and Mach number change range is large, in order to ensure the spatial resolution and fine measurement, the following implementation manner can be adopted:

[0091] As Figures 1 to 6 shown is a three-hole pressure probe suitable for wide measurement range between turbine stages,Figure 7 and Figure 8 Figure 1 is a schematic diagram of the probe used in the present application for measuring the two-dimensional flow field at the outlet of the second stator of a multi-stage turbine.

[0092] In this embodiment, the three-hole pressure probe suitable for wide-range measurement between turbine stages is composed of a probe support rod (1), a probe head (2), a head support rod (3), a middle pressure measuring hole (4), a left pressure measuring hole (5), a right pressure measuring hole (6), a pressure pipe channel (7), and a pressure pipe (8). The head support rod (3) is welded to the probe support rod (1). The probe head (2) is located at the front end of the head support rod (3) and has the middle pressure measuring hole (4), the left pressure measuring hole (5), and the right pressure measuring hole (6) which are not connected to each other. The pressure pipe (8) is encapsulated in the probe support rod (1) and has one end connected to the three pressure measuring holes of the probe head (2) and the other end drawn out from the tail of the probe support rod (1) through the pressure pipe channel (7).

[0093] Further, the probe support rod (1) is a cylinder with a cross-sectional diameter of 8 mm.

[0094] Further, the head support rod (3) has a "L" shape as a whole, with a circular arc transition at the middle corner. The cross section of the head support rod (3) is an equilateral triangle with the top angle directly facing the incoming flow direction, the side length being 2.5 mm, and the three edges being polished with rounded corners. The side surface of the head support rod (3) is used as a horizontal positioning surface of the probe.

[0095] Further, the size of the head support rod (3) in the top direction projection does not exceed the cross section of the probe support rod (1), and the distance between the outer edge of the cross section of the probe support rod (1) and the head support rod (3) is 0.5 mm. The distance between the center axis of the probe head (2) and the connection surface of the head support rod (3) and the probe support rod (1) is 3 times the length of the bottom edge of the probe support rod (1).

[0096] Further, the probe head (2) has a sharp wedge shape with an included angle of 60°. The middle pressure measuring hole (4), the left pressure measuring hole (5), and the right pressure measuring hole (6) are arranged in a "1" shape. The center axis of the middle pressure measuring hole (4) directly faces the incoming flow direction. The height of the probe head (2) is 1 mm, and the width is 3 mm.

[0097] Further, the wide-range calibration of the three-hole pressure probe suitable for wide-range measurement between turbine stages is carried out in a calibration wind tunnel. The calibration speed range is 0.1 Mach to 1.4 Mach, the calibration interval is 0.1 Mach, the deflection angle range is -70° to 70°, and the calibration interval is 5°.

[0098] Further, the above calibration data are processed by the three-domain method and the combination method in the wide-range three-hole probe data processing method. The three-domain method is characterized by:

[0099] The three-domain method is characterized by:

[0100] Step one: the deflection angle coefficient, total pressure coefficient and static pressure coefficient are defined as follows:

[0101] Deflection angle coefficient:

[0102]

[0103] Total pressure coefficient:

[0104]

[0105] Static pressure coefficient:

[0106]

[0107] Wherein: C py is the deflection angle coefficient, C pt is the total pressure coefficient, C ps is the static pressure coefficient, the total pressure and static pressure of the incoming flow of the calibration wind tunnel are P t and P s , the pressure values measured by the middle hole, left hole and right hole of the three-hole pressure probe are P1, P2 and P3 respectively.

[0108] Step two: the calibration curves of the deflection angle-deflection angle coefficient, deflection angle-total pressure coefficient and deflection angle-static pressure coefficient at different deflection angles of each incoming flow Mach number are obtained by the definition in step one, the calibration curves are divided into three domains at the points where the left hole pressure value is equal to the middle hole pressure value and the right hole pressure value is equal to the middle hole pressure value, and the calibration curves are shown in Figure 9 .

[0109] Step three: when the actual measurement of the two-dimensional flow field at the outlet of the second stage stator of the multi-stage turbine is performed, the deflection angle coefficient is calculated by using the measured pressure values of the three holes, and then the positive and negative of the deflection angle coefficient and the size of the left and right hole pressure values are compared to determine the domain corresponding to the deflection angle coefficient-deflection angle calibration curve for interpolation calculation of the deflection angle initial value:

[0110] When the left and right hole pressure values are equal, the deflection angle is 0°;

[0111] When the left hole pressure value is greater than the right hole pressure value and the deflection angle coefficient is negative, the right domain of the calibration curve is selected;

[0112] When the left hole pressure value is greater than the right hole pressure value and the deflection angle coefficient is positive, the middle domain of the calibration curve is selected;

[0113] When the left hole pressure value is less than the right hole pressure value and the deflection angle coefficient is negative, the middle domain of the calibration curve is selected;

[0114] When the left hole pressure value is less than the right hole pressure value and the deflection angle coefficient is positive, the left domain of the calibration curve is selected.

[0115] Step four: use the deflection angle initial value, and then calculate the total pressure initial value, static pressure initial value and Mach number initial value according to the deflection angle-total pressure coefficient and deflection angle-static pressure coefficient calibration curves.

[0116] Step five: according to the Mach number initial value, iterate the calibration curves at different Mach numbers, and finally obtain the deflection angle, total pressure, static pressure and Mach number of the measured flow field.

[0117] Combined method:

[0118] Step one: divide the calibration data into three domains according to different deflection angle ranges, which are:

[0119] Left domain: -70°-10°

[0120] Middle domain: -30°-30°

[0121] Right domain: 10°-70°

[0122] Step two: the definitions of the deflection angle coefficient, total pressure coefficient and static pressure coefficient in each domain are as follows:

[0123] Left domain and right domain:

[0124]

[0125] Middle domain:

[0126]

[0127] Where: C py is the deflection angle coefficient, C pt is the total pressure coefficient, and C ps is the static pressure coefficient. The total pressure and static pressure of the calibration wind tunnel are P t and P s , and the pressure values measured by the middle hole, left hole and right hole of the three-hole pressure probe are P1, P2 and P3, respectively.

[0128] Step three: obtain the deflection angle-deflection angle coefficient, deflection angle-total pressure coefficient and deflection angle-static pressure coefficient calibration curves of each domain at each incoming Mach number according to the definitions in step two, as shown in Figure 10 .

[0129] Step four: during actual measurement, compare the pressure values of each hole according to the three pressure sensing hole data obtained by wide range calibration, and select the corresponding domain according to the direction of the hole with the maximum pressure value. The pressure maximum hole distribution of the calibration data is shown in Figure 11 ; calculate the deflection angle coefficient according to the deflection angle coefficient definition of the domain, and then perform interpolation calculation on the deflection angle-deflection angle coefficient calibration curve of the domain to obtain the deflection angle initial value.

[0130] Step five: using the deflection angle initial value, the total pressure initial value, the static pressure initial value and the Mach number initial value are calculated according to the deflection angle-total pressure coefficient and the deflection angle-static pressure coefficient calibration curves of the domain;

[0131] Step six: the deflection angle, the total pressure, the static pressure and the Mach number of the measured flow field are finally obtained according to the calibration curves of different Mach numbers in the domain based on the Mach number initial value.

Claims

1. A three-hole pressure probe suitable for wide range of turbine stage measurement, consisting of probe strut (1), probe head (2), head strut (3), pressure measuring middle hole (4), pressure measuring left hole (5), pressure measuring right hole (6), pilot tube channel (7), pilot tube (8), characterized in that: The head support rod (3) is welded with the probe support rod (1); the probe head (2) is located at the front end of the head support rod (3), and the pressure measuring middle hole (4), the pressure measuring left hole (5) and the pressure measuring right hole (6) which are not communicated with each other are formed; the pressure guide pipe (8) is encapsulated in the probe support rod (1), one end of the pressure guide pipe (8) is communicated with the three pressure measuring holes of the probe head (2), and the other end of the pressure guide pipe (8) is led out from the tail of the probe support rod (1) through the pressure guide pipe channel (7); Further, the probe support rod (1) is a cylinder, and the cross-sectional diameter is 3-30 mm; Further, the head support rod (3) is in the shape of a "L" as a whole, a circular arc is arranged at the middle corner, the cross section is triangular, the top angle is opposite to the flow direction, the included angle is 30-120°, the length of the bottom side is 0.6-5 mm, and the three edges are polished or kept sharp; The side surface of the head support rod (3) is used as the horizontal positioning surface of the probe; Further, the size of the head support rod (3) in the top direction projection does not exceed the cross section of the probe support rod (1), the distance between the cross section of the probe support rod (1) and the head support rod (3) is 0.5-1 mm, and the distance between the center axis of the probe head (2) and the connecting surface of the head support rod (3) and the probe support rod (1) is 2-6 times the length of the bottom side of the probe support rod (1); Further, the probe head (2) is in the shape of a sharp wedge, the included angle is 30-120°, the pressure measuring middle hole (4), the pressure measuring left hole (5) and the pressure measuring right hole (6) are arranged in the shape of "1", the center axis of the pressure measuring middle hole (4) is opposite to the flow direction, the height of the probe head (2) is 0.4-2 mm, and the width of the probe head (2) is 0.8-4 mm; Further, the wide-range calibration of the three-hole pressure probe is carried out in a calibration wind tunnel, the calibration speed range is 0.1-1.4 Mach, and the deflection angle range is -80°-80°. Further, the calibration curves of the deflection angle coefficient-deflection angle, the deflection angle-total pressure coefficient and the deflection angle-static pressure coefficient at different deflection angles under each Mach number are obtained through the wide-range three-hole pressure probe data processing method.

2. A three-hole pressure probe suitable for wide range of measurement in turbine stage according to claim 1, characterized in that: The wide-range three-hole pressure probe data processing method comprises a two-domain method and a combination method.

3. A three-hole pressure probe suitable for wide range of measurement between turbine stages according to claim 2, characterized in that: The two-domain method comprises the following steps: Step one: the definitions of the deflection angle coefficient, the total pressure coefficient and the static pressure coefficient are as follows: Deflection angle coefficient: Total pressure coefficient: Static pressure coefficient: wherein: C py is the deflection angle coefficient, C pt is the total pressure coefficient, C ps is the static pressure coefficient, the total pressure and static pressure of the incoming flow of the calibration wind tunnel are P t and P s , the pressure values measured by the middle hole, left hole and right hole of the three-hole pressure probe are P1, P2 and P3, respectively; Step two: the calibration curves of the deflection angle-deflection angle coefficient, the deflection angle-total pressure coefficient and the deflection angle-static pressure coefficient at different deflection angles under each Mach number are obtained through the definition in step one, and the calibration curves are divided into two domains at the point where the left hole pressure value is equal to the right hole pressure value; Step three: the deflection angle coefficient is calculated by using the measured pressure values of the three holes in actual measurement, then the left hole pressure value and the right hole pressure value are compared, the domain corresponding to the deflection angle coefficient-deflection angle calibration curve is selected, and the deflection angle initial value is calculated through interpolation: When the left hole pressure value is equal to the right hole pressure value, the deflection angle is 0°; When the left hole pressure value is greater than the right hole pressure value, the left domain of the calibration curve is selected; When the right hole pressure value is greater than the left hole pressure value, the right domain of the calibration curve is selected. Step four: using the deflection angle initial value, the total pressure initial value, the static pressure initial value and the Mach number initial value are calculated by the deflection angle-total pressure coefficient and the deflection angle-static pressure coefficient calibration curve interpolation; Step five: according to the Mach number initial value, the calibration curve under different Mach number is iterated, and the airflow deflection angle, total pressure, static pressure and Mach number of the measured flow field are finally obtained.

4. A three-hole pressure probe suitable for wide range of measurement in turbine stage according to claim 2, characterized in that: The combination method has the following steps: Step one: the calibration data is divided into three domains according to different deflection angle ranges, which are: Left domain: -80°-10° Middle domain: -30°-30° Right domain: 10°-80° Step two: the deflection angle coefficient, total pressure coefficient and static pressure coefficient of each domain are defined as follows: Left domain and right domain: Middle domain: wherein: C py is the deflection angle coefficient, C pt is the total pressure coefficient, C ps is the static pressure coefficient, the total pressure and static pressure of the incoming flow of the calibration wind tunnel are P t and P s , the pressure values measured by the middle hole, left hole and right hole of the three-hole pressure probe are P1, P2 and P3, respectively; Step three: the deflection angle-deflection angle coefficient, deflection angle-total pressure coefficient and deflection angle-static pressure coefficient calibration curves of each domain under each incoming flow Mach number are obtained respectively through the definition in step two; Step four: during actual measurement, according to the three pressure hole data obtained by wide range calibration, the pressure values of each hole are compared, the corresponding domain is selected according to the direction of the hole with the maximum pressure value, the deflection angle coefficient is calculated according to the definition of the deflection angle coefficient of the domain, and then the deflection angle initial value is calculated by the deflection angle-deflection angle coefficient calibration curve interpolation of the domain; Step five: using the deflection angle initial value, the total pressure initial value, the static pressure initial value and the Mach number initial value are calculated by the deflection angle-total pressure coefficient and the deflection angle-static pressure coefficient calibration curve interpolation; Step six: according to the Mach number initial value, the calibration curve under different Mach number of the domain is iterated, and the airflow deflection angle, total pressure, static pressure and Mach number of the measured flow field are finally obtained.

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