Plane cascade experiment piece, experiment system and experiment method capable of simulating centrifugal force load of blade

Abstract

The invention discloses a plane cascade experiment piece, experiment system and experiment method.The experiment piece comprises a cascade, an upper mounting plate, a lower mounting plate, a clamp, a force sensor and a stretching structure, the cascade comprises an upper grid plate, a lower grid plate and a plurality of experiment blades, and the roots of the experiment blades are connected with the lower grid plate in a limiting mode; the top of the experimental blade extends out of the upper grid plate and is fixedly connected with one end of the clamp, the other end of the clamp is connected with the tensile structure through the force sensor, and the upper mounting plate and the lower mounting plate are connected with the upper grid plate and the lower grid plate respectively. The centrifugal load borne by the rotating blade can be simulated, so that the more accurate aerodynamic performance of the blade grid is obtained.

Description

Technical Field

[0001] The invention belongs to the field of aero-engine experimental devices, and in particular provides a plane blade cascade experimental piece, an experimental system and an experimental method capable of simulating the centrifugal force load of blades. Background Art

[0002] Blades are one of the core components of aircraft engines and have a great impact on the performance level of aircraft engines. Aircraft engines rely on high-speed rotating turbine blades to output a certain amount of power to drive the compressor to work. The rotation of the compressor blades absorbs the power transmitted by the turbine, thereby achieving gas compression and improving the thermal efficiency of the engine. The high aerodynamic performance of high-speed rotating compressor blades and turbine blades is crucial to achieving this function. During the engine development stage, due to the difficulty of testing and funding constraints, a large number of rotating state blade cascade experiments could not be effectively carried out, but more plane blade cascade wind tunnel blowing experiments were carried out, that is, the blades were placed statically in the plane blade cascade wind tunnel, and the aerodynamic performance of the blade cascade was measured through the blowing experiment. However, with the increase of engine speed, the centrifugal force generated by the rotation of the blades in the engine becomes larger and larger. The deformation of the blades under the action of the centrifugal force load will change the aerodynamic performance of the blade cascade. Therefore, there is a certain difference between the aerodynamic performance data of the blade cascade measured by the static blades in the prior art and the aerodynamic performance of the blade cascade in the rotating state.

[0003] Therefore, how to improve the existing plane blade test piece or experimental system to simulate the centrifugal load of the blade in a rotating state, so as to accurately obtain the aerodynamic performance of the blade in a rotating state in a plane blade wind tunnel test environment, has become an urgent problem to be solved. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a plane blade cascade test piece, an experimental system and an experimental method that can simulate the centrifugal force load on the blade, so as to solve the problem that the existing plane blade cascade wind tunnel experiment simulates the centrifugal load on the rotating blade, and thus cannot accurately obtain the aerodynamic performance of the blade cascade in the rotating state.

[0005] On the one hand, the present invention provides a planar blade cascade test piece that can simulate the centrifugal force load of blades, comprising: a blade cascade, an upper mounting plate, a lower mounting plate, a fixture, a force sensor and a tensile structure, wherein the blade cascade comprises an upper cascade plate, a lower cascade plate and a plurality of experimental blades spaced between the upper cascade plate and the lower cascade plate, the root of the experimental blade is limitedly connected to the lower cascade plate, the top of the experimental blade extends out of the upper cascade plate and is fixedly connected to one end of the fixture, the other end of the fixture is connected to the tensile structure through a force sensor, the upper mounting plate and the lower mounting plate are respectively connected to the upper cascade plate and the lower cascade plate, and are used to fix the planar blade cascade test piece that can simulate the centrifugal force load of blades on a blade cascade turntable on a stationary blade cascade test bench, the tensile structure is used to apply a force to the experimental blade, and the force sensor is used to detect the magnitude of the force.

[0006] Preferably, the blade grid further includes foil blades, which are arranged on both sides of all experimental blades, and both ends of the foil blades are respectively plugged with the upper grid plate and the lower grid plate through tenons.

[0007] Further preferably, the fixture includes a top plate and a connecting plate connected to the top plate, the top plate is in an inverted T-shape, the top of the top plate is used to connect to the tensile structure through the force sensor, and the connecting plate is fixedly connected to the bottom of the top plate and is connected one-to-one with the experimental blades.

[0008] Further preferably, a slot cooperating with the experimental blade is provided in the middle of the connecting plate, and the top of the experimental blade is inserted into the slot of the experimental blade and fixedly connected to the connecting plate by bolts.

[0009] Further preferably, the tensile structure includes a door-shaped frame, an adjusting bolt and an adjusting nut, wherein the door-shaped frame is fixedly connected to the upper portion of the upper mounting plate, a threaded hole is provided at the top of the door-shaped frame, the adjusting bolt is cooperatively installed in the threaded hole, the bottom of the adjusting bolt is connected to the force sensor, and the adjusting nut is cooperatively connected to the adjusting bolt and is located above the door-shaped frame.

[0010] The present invention also provides a planar blade cascade experimental system that can simulate the centrifugal force load of blades, comprising: a stationary blade cascade test bench, a three-hole probe and the above-mentioned planar blade cascade experimental piece that can simulate the centrifugal force load of blades, wherein the stationary blade cascade test bench is provided with an air inlet, a blade cascade turntable and a sensor measurement system, the planar blade cascade experimental piece that can simulate the centrifugal force load of blades is fixedly mounted on the blade cascade turntable through an upper mounting plate and a lower mounting plate, the blade cascade turntable is used to adjust the blade cascade inlet angle of attack, the sensor measurement system is used to measure the inlet total pressure, inlet static pressure and outlet static pressure of the blade cascade, and the three-hole probe is used to measure the blade cascade airflow backward angle and outlet total pressure.

[0011] Preferably, the three-hole probe is arranged at a distance of 0.7 times the cascade pitch from the cascade in the direction of the cascade geometric outlet angle of the test blade.

[0012] The present invention also provides a method for testing the aerodynamic performance of a planar blade cascade that can simulate the centrifugal force load on blades. The method uses the above-mentioned planar blade cascade test system that can simulate the centrifugal force load on blades, and simulates the centrifugal force load on the blade in a rotating state by adjusting the force applied to the test blade by the tensile structure, and obtains the aerodynamic performance of the blade cascade in a rotating state through data measured by a sensor measurement system and a three-hole probe.

[0013] The plane blade cascade test piece provided by the present invention can simulate the centrifugal force load of the blade. A force can be applied to the test blade through a tensile structure, thereby simulating the centrifugal force load on the blade in a rotating state. The magnitude of the applied force can be detected by a force sensor. When the set load is reached, a wind tunnel test can be carried out to obtain the aerodynamic performance of the blade cascade.

[0014] The present invention provides a plane blade cascade experimental system and an experimental method capable of simulating the centrifugal force load on blades. By adopting the above-mentioned plane blade cascade experimental piece, the centrifugal force load on the blades in a rotating state can be simulated, thereby obtaining more accurate experimental data and experimental results. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments:

[0016] Figure 1 A schematic diagram of the structure of a plane cascade test piece provided by the present invention that can simulate the centrifugal force load of blades;

[0017] Figure 2 This is a schematic diagram of the structure of the experimental blade;

[0018] Figure 3 It is a schematic diagram of the structure of the foil blade;

[0019] Figure 4 is a schematic diagram of the structure of the fixture;

[0020] Figure 5 A schematic structural diagram of a plane blade cascade experimental system provided by the present invention that can simulate the centrifugal force load on blades. DETAILED DESCRIPTION

[0021] The present invention will be further explained below in conjunction with specific implementation schemes, but the present invention is not limited thereto.

[0022] In order to simulate the centrifugal force load of the blades and obtain the aerodynamic performance of the rotating blade cascade more accurately, such as Figures 1 to 4As shown, the present invention provides a plane blade cascade test piece that can simulate the centrifugal force load of blades, including: a blade cascade 1, an upper mounting plate 2, a lower mounting plate 3, a fixture 4, a force sensor 5 and a tensile structure 6, wherein the blade cascade 1 includes an upper cascade plate, a lower cascade plate and a plurality of experimental blades 11 spaced between the upper cascade plate and the lower cascade plate, preferably, the number of the experimental blades is greater than 4, and the root of the experimental blade 11 is limitedly connected to the lower cascade plate, such as Figure 2 As shown, a base 111 is provided at the root of the experimental blade, which is used to limit the experimental blade from being separated from the lower grid plate during the experiment. The root of the experimental blade can also be directly fixedly connected to the lower grid plate. The top of the experimental blade 11 extends out of the upper grid plate and is fixedly connected to one end of the clamp 4. The other end of the clamp 4 is connected to the tensile structure 6 through a force sensor 5. The upper mounting plate 2 and the lower mounting plate 3 are respectively connected to the upper grid plate and the lower grid plate, and are used to fix the plane blade test piece that can simulate the centrifugal force load of the blade on the blade turntable on the stationary blade test bench. The tensile structure 6 is used to apply a force to the experimental blade 11, and the force sensor 5 is used to detect the magnitude of the force.

[0023] Before conducting an experiment using the plane cascade test piece that can simulate the centrifugal force load of the blade, the test piece is first fixed to the cascade turntable on the stationary cascade test bench through a mounting plate. The method for simulating the centrifugal force load of the blade is as follows: a force is applied to the test blade through a tensile structure and the magnitude of the applied force is detected by a force sensor. When the set load is reached, a wind tunnel experiment can be carried out to obtain more accurate aerodynamic performance of the cascade.

[0024] As an improvement of the technical solution, the blade cascade 1 further includes foil blades 12, and the foil blades 12 are arranged on both sides of all experimental blades 11. Figure 1 A cascade structure with four experimental blades and three foil blades is given, wherein the four experimental blades constitute three cascade channels, which can ensure good cascade periodicity. The two ends of the foil blade 12 are respectively plugged with the upper cascade plate and the lower cascade plate through tenons. Figure 3 This is a schematic diagram of the structure of the supporting blade.

[0025] As an improvement of the technical solution, Figure 4 As shown, the fixture 4 includes a top plate 41 and a connecting plate 42 connected to the top plate 41, the top plate 41 is in an inverted T shape, the top of the top plate 41 is used to connect with the tensile structure 6 through the force sensor 5, and the connecting plate 42 is fixedly connected to the bottom of the top plate 41 and is connected one-to-one with the experimental blades 11.

[0026] As an improvement of the technical solution, Figure 4As shown, a slot matching with the experimental blade 11 is provided in the middle of the connecting plate 42 , and the top of the experimental blade 11 is inserted into the slot of the experimental blade 11 and fixedly connected with the connecting plate 42 by bolts.

[0027] As an improvement of the technical solution, Figure 1 As shown, the tensile structure 6 includes a door-shaped frame 61, an adjusting bolt 62 and an adjusting nut 63, wherein the door-shaped frame 61 is fixedly connected to the upper portion of the upper mounting plate 3, a threaded hole is provided at the top of the door-shaped frame 61, the adjusting bolt 62 is cooperatively installed in the threaded hole, the bottom of the adjusting bolt 62 is connected to the force sensor 5, the adjusting nut 63 is cooperatively connected to the adjusting bolt 62 and is located above the door-shaped frame 61, and the simulated centrifugal load can be adjusted by rotating the adjusting nut.

[0028] like Figure 5 As shown, the present invention also provides a plane blade cascade test system capable of simulating blade centrifugal force load, comprising: a stationary blade cascade test bench 7, a three-hole probe and a plane blade cascade test piece capable of simulating blade centrifugal force load according to any one of claims 1 to 5, wherein the stationary blade cascade test bench 7 is provided with an air inlet duct 71, a blade cascade rotating disk 72 and a sensor measurement system, the plane blade cascade test piece capable of simulating blade centrifugal force load is fixedly mounted on the blade cascade rotating disk 72 through an upper mounting plate 2 and a lower mounting plate 3, the air inlet duct 71 is used to provide an aerodynamic environment, the blade cascade rotating disk 72 is used to adjust the blade cascade inlet angle of attack, the sensor measurement system is used to measure the inlet total pressure, inlet static pressure and outlet static pressure of the blade cascade, and the three-hole probe is used to measure the airflow backward angle and outlet total pressure of the blade cascade.

[0029] The plane blade cascade experimental system capable of simulating the centrifugal force load of blades adopts the above-mentioned plane blade cascade experimental piece capable of simulating the centrifugal force load of blades, and can adjust the force applied to the experimental blades through the tensile structure, thereby simulating the centrifugal force load on the blades in a rotating state, and obtaining accurate aerodynamic performance of the blades in a rotating state.

[0030] As an improvement of the technical solution, the three-hole probe is arranged at a position 0.7 times the cascade pitch in the cascade geometric outlet angle direction of the experimental blade 11 .

[0031] The present invention also provides a method for testing the aerodynamic performance of a planar blade cascade that can simulate the centrifugal force load on blades. The planar blade cascade test system that can simulate the centrifugal force load on blades is used. The centrifugal force load on the blade in a rotating state is simulated by adjusting the force applied by the tensile structure 6 to the test blade 11, and the aerodynamic performance of the blade cascade in a rotating state is obtained through data measured by a sensor measurement system and a three-hole probe.

[0032] An example of a complete experimental method is given below.

[0033] S1: Install the plane cascade test piece on the cascade turntable of the stationary cascade test bench and adjust the cascade inlet attack angle;

[0034] S2: Use the tensile structure to adjust the force on the experimental blade to simulate the centrifugal load of the blade in the rotating state;

[0035] S3: Start the wind tunnel experiment, measure the inlet total pressure, inlet static pressure and outlet static pressure of the cascade through the sensor measurement system, and measure the cascade airflow backward angle and outlet total pressure through the three-hole probe;

[0036] S4: Using the measured aerodynamic data, the aerodynamic performance of the blade is calculated. The calculation method of the specific performance parameters is as follows:

[0037] Total pressure loss coefficient:

[0038] Pressure ratio:

[0039] Airflow turning angle: Δβ=β 2k -β 1k +i-δ

[0040] in, is the total inlet pressure, P 1s is the inlet static pressure, is the total outlet pressure, P 2s is the outlet static pressure, β 2k is the cascade exit geometry angle, β 1k is the blade inlet geometric angle, i is the blade inlet attack angle, and δ is the blade airflow backward angle.

[0041] The detailed description of the present invention is written in a progressive manner, emphasizing the differences between the various implementations, and similar parts thereof can be referred to each other.

[0042] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in this field without departing from the purpose of the present invention.

Claims

1. A plane cascade test piece capable of simulating centrifugal force load on blades, characterized in that: include: A blade grid (1), an upper mounting plate (2), a lower mounting plate (3), a fixture (4), a force sensor (5) and a tensile structure (6), wherein the blade grid (1) comprises an upper grid plate, a lower grid plate and a plurality of experimental blades (11) arranged at intervals between the upper grid plate and the lower grid plate, the root of the experimental blade (11) is limitedly connected to the lower grid plate, the top of the experimental blade (11) extends out of the upper grid plate and is fixedly connected to one end of the fixture (4), the other end of the fixture (4) is connected to the tensile structure (6) through the force sensor (5), the upper mounting plate (2) and the lower mounting plate (3) are respectively connected to the upper grid plate and the lower grid plate, and are used to fix the plane blade grid test piece that can simulate the centrifugal force load of the blade on the blade grid turntable on the stationary blade grid test table, the tensile structure (6) is used to apply a force to the experimental blade (11), and the force sensor (5) is used to detect the magnitude of the force.

2. The plane cascade test piece capable of simulating blade centrifugal force load according to claim 1, characterized in that: The blade grid (1) further comprises a foil blade (12), wherein the foil blade (12) is arranged on both sides of all the experimental blades (11), and the two ends of the foil blade (12) are respectively plugged into the upper grid plate and the lower grid plate through tenons.

3. The plane cascade test piece capable of simulating blade centrifugal force load according to claim 1, characterized in that: The fixture (4) comprises a top plate (41) and a connecting plate (42) connected to the top plate (41); the top plate (41) is in an inverted T-shape; the top of the top plate (41) is used to connect to the tensile structure (6) via the force sensor (5); the connecting plate (42) is fixedly connected to the bottom of the top plate (41) and is connected one-to-one with the experimental blades (11).

4. The plane cascade test piece capable of simulating blade centrifugal force load according to claim 3, characterized in that: A slot matching the experimental blade (11) is provided in the middle of the connecting plate (42); the top of the experimental blade (11) is inserted into the slot of the experimental blade (11) and is fixedly connected to the connecting plate (42) by bolts.

5. The plane cascade test piece capable of simulating centrifugal force load of blades according to claim 1, characterized in that: The tensile structure (6) comprises a door-shaped frame (61), an adjusting bolt (62) and an adjusting nut (63), wherein the door-shaped frame (61) is fixedly connected to the upper part of the upper mounting plate (3), a threaded hole is provided at the top of the door-shaped frame (61), the adjusting bolt (62) is cooperatively installed in the threaded hole, the bottom of the adjusting bolt (62) is connected to the force sensor (5), and the adjusting nut (63) is cooperatively connected to the adjusting bolt (62) and is located above the door-shaped frame (61).

6. A plane cascade test system capable of simulating centrifugal loads on blades, characterized in that: include: A stationary cascade test bench (7), a three-hole probe and a plane cascade test piece capable of simulating blade centrifugal force loads as claimed in any one of claims 1 to 5, wherein the stationary cascade test bench (7) is provided with an air inlet (71), a cascade rotating disk (72) and a sensor measurement system, the plane cascade test piece capable of simulating blade centrifugal force loads is fixedly mounted on the cascade rotating disk (72) via an upper mounting plate (2) and a lower mounting plate (3), the cascade rotating disk (72) is used to adjust the cascade inlet attack angle, the sensor measurement system is used to measure the inlet total pressure, inlet static pressure and outlet static pressure of the cascade, and the three-hole probe is used to measure the cascade airflow backward angle and outlet total pressure.

7. The plane cascade test system capable of simulating blade centrifugal force load according to claim 6, characterized in that: The three-hole probe is arranged at a position 0.7 times the cascade pitch in the cascade geometric outlet angle direction of the experimental blade (11).

8. A method for testing the aerodynamic performance of a plane cascade that can simulate the centrifugal force load of blades, characterized in that: A planar cascade experimental system capable of simulating the centrifugal force load on blades as described in claim 6 or 7 is used, and the centrifugal force load on the blades in a rotating state is simulated by adjusting the force applied by the tensile structure (6) to the experimental blades (11), and the aerodynamic performance of the cascade in a rotating state is obtained through data measured by a sensor measurement system and a three-hole probe.

Images