A kind of annular blade performance tester

Abstract

The present invention proposes an annular blade performance tester, comprising an intake system, an exhaust system, a boundary layer suction system, and a cooling system; the annular blade performance tester proposed in the present invention can cover subsonic, transonic, and supersonic ranges, and includes plane blades, fan-shaped blades, and annular blade test functions, can fully simulate the actual flow field conditions of the blade test section, can provide better flow field quality, and accurately reflect the secondary flow loss conditions in the blade, and can obtain more accurate flow field parameters to facilitate the evaluation of the performance of the blade, thereby determining the direction of improvement.

Description

Technical Field

[0001] The invention relates to the technical field of aero-engine testing, and in particular to an annular blade cascade testing device. Background Art

[0002] The performance of the cascade directly affects the performance indicators of aircraft engines. Detailed research on the complex flow field structure and loss mechanism in the cascade flow channel, exploring methods to reduce energy loss in the cascade flow channel and improve the aerodynamic performance of the cascade have become important research contents for improving the performance of aircraft engines. From the existing cascade theory and experiments, it can be seen that the flow in the cascade is very complex and has many influencing factors, including geometric factors such as airflow angle and viscosity, aerodynamic factors such as the incoming flow Mach number, shock wave boundary layer interference, etc. Due to the staggered arrangement of the rotating blades and the stationary blades, the airflow wake and the blade movement interfere with each other, and the interference of viscosity and shock waves in the flow, all of which cause the instability and extreme complexity of the flow in the cascade, and present the common characteristics of rotation and three-dimensionality in rotating machinery; therefore, it is necessary and urgent to establish a better tester to accurately determine the flow field parameters in the cascade. Summary of the invention

[0003] Aiming at the defects in the prior art, the present invention provides an annular blade cascade performance tester.

[0004] An annular blade performance tester, characterized in that it includes an air intake system, an exhaust system, a boundary layer suction system, and a cooling system;

[0005] The air intake system includes an air source, an air intake pipeline, a straight pipe section, a diffusion section, a stabilizing section, a convergent section, a nozzle, and a cascade test section; the air intake pipeline includes large and small air intake pipes and an exhaust pipe; the large and small air intake pipes are joined and connected to form a three-way joint; the rear of the three-way joint is connected to the straight pipe section through an expansion joint; the rear of the straight pipe section is connected to a conical diffusion section; the diffusion section is connected to the stabilizing section; the stabilizing section includes a rectifying section and a pressure stabilizing section; a sintered wire mesh and a honeycomb rectifier are arranged in sequence inside the rectifying section; a damping net is arranged inside the pressure stabilizing section; the pressure stabilizing section is connected to the convergent section; the convergent section is connected to the cascade test section through a nozzle; the outlet of the cascade test section is connected to the exhaust system; the cascade test section includes an air intake section and an exhaust section, and inlet and outlet measurement sections are respectively provided, and total pressure probes, total temperature probes and static pressure measuring points are arranged on them;

[0006] The exhaust system comprises a horizontal exhaust collector fixed in the horizontal direction and a mobile exhaust collector movable in the circumferential direction; the mobile exhaust collector is fixed on an arc guide rail and can move steplessly along the arc guide rail; the horizontal exhaust collector and the mobile exhaust collector are each connected to a section of pipeline and are connected to the same exhaust silencer tower;

[0007] The boundary layer suction system includes a vacuum pump, a vacuum box, and a vacuum pipeline; the vacuum pump is connected to the vacuum box via an electric gate valve; the vacuum box divides into a plurality of suction branches connected to the boundary layer of the cascade test section;

[0008] The cooling air system comprises an air source and a distributor; the air source is connected to the distributor via a gate valve and a pipeline; the distributor is connected to the blade grid test section via a plurality of cooling branches.

[0009] The specific beneficial effects of the present invention are as follows:

[0010] (1) The annular blade performance tester proposed in the present invention can cover the subsonic, transonic and supersonic ranges, and includes the test functions of plane blades, fan-shaped blades and annular blades. It can fully simulate the actual flow field conditions of the blade test section, provide better flow field quality, and accurately reflect the secondary flow loss in the blade. It can obtain more accurate flow field parameters to facilitate the evaluation of the performance of the blade, thereby determining the direction of improvement.

[0011] (2) The air intake system of the present invention is provided with large and small air intake pipes and an air discharge pipe. All three pipes are provided with a pressure regulating valve and a fine adjustment valve. The three can jointly adjust the air intake pressure and flow rate. The adjustment range is finer and the adjustment accuracy is higher. The requirements of the annular cascade performance test for different air intake pressures and flow rates are met, and the flow field in the downstream test section is ensured to have a high Mach number control accuracy and good flow field quality. At the same time, the exhaust system is provided with a horizontal exhaust collector and a mobile exhaust collector. The mobile exhaust collector can move steplessly along a pre-laid arc guide rail within the range of the airflow angle change at the outlet of the cascade test section, so as to ensure that the gas discharged from the cascade test section is completely recovered without affecting the normal test process.

[0012] (3) The present invention is provided with a boundary layer suction system and a cooling air system to cooperate with the blade cascade test section, wherein the boundary layer suction system can suction the left and right side walls and the upper and lower chambers of the blade cascade test section, and can adjust the suction pressure and suction volume, so that the flow field formed around the blade cascade test section is the flow field required for the test, thereby ensuring that the test results are sufficiently accurate; and the cooling air system can pass cooling gas into the turbine blades of the blade cascade test section, so that the test device has the conditions for conducting a turbine cooling test. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram of the annular blade performance tester of the present invention;

[0014] Figure 2 It is the layout diagram of the intake system and exhaust system of the annular cascade performance tester of the present invention;

[0015] Figure 3 This is the schematic diagram of the intake system;

[0016] Figure 4It is a schematic diagram of the exhaust collector structure;

[0017] Figure 5 This is the principle diagram of the boundary layer suction system;

[0018] Figure 6 This is the schematic diagram of the air conditioning system;

[0019] Figure 7 This is a schematic diagram of the nozzle carriage structure. DETAILED DESCRIPTION

[0020] The present invention is further described below in conjunction with the accompanying drawings and embodiments. In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0021] Example 1

[0022] like Figure 1 , 2As shown in Figure 3, the present invention proposes an annular blade performance tester, including an intake system, an exhaust system, a boundary layer suction system, and a cooling system; the intake system includes an air source, an intake pipeline, a straight pipe section 13, a diffuser section 14, a stabilizing section 15, a convergent section 16, a nozzle, and a blade test section 17 connected in sequence; the intake pipeline includes large and small intake pipes 11, 12 and an exhaust pipe 10, each of which has a set of pressure regulating valves (112, 122, 102 in the figure) and fine adjustment valves (111, 121, 101 in the figure) to ensure that the flow field in the downstream test section has a high Mach number control accuracy; the large and small intake pipes 11, 12 are connected together to form a three-way joint 18; the rear of the three-way joint 18 is connected to the straight pipe section 13 through an expansion joint; the rear of the straight pipe section 13 is connected to the conical diffuser section 14, and the function of the diffuser section is to connect The straight pipe section 13 and the stabilizing section 15 are used to decelerate and increase the pressure to stabilize the flow field to a certain extent. In this embodiment, a double-layer diffusion section is used to achieve better flow field quality; the stabilizing section includes a rectifying section and a pressure stabilizing section; a sintered wire mesh and a honeycomb rectifier are arranged in sequence inside the rectifying section, and the honeycomb rectifier and the damping net are both modularly designed; a damping net is arranged inside the pressure stabilizing section, and a total temperature and total pressure mounting seat is arranged near the outlet of the pressure stabilizing section, and two 5-point total pressure comb probes, two 5-point total temperature probes and 8 static pressure measuring points are arranged on the same plane; the pressure stabilizing section is connected to the convergent section, and the convergent section 16 is connected to the blade test section 17 through the nozzle. The blade test section 17 includes an intake section and an exhaust section, and inlet and outlet measurement sections are respectively arranged, and four 5-point total pressure probes, four 5-point total temperature probes and 8 static pressure measuring points are arranged, and the above probes and measuring points are all used to monitor the flow field conditions in real time.

[0023] The blade cascade test section in the present invention includes an annular blade cascade test section, a fan-shaped blade cascade test section, and a plane blade cascade test section, all of which are adapted to the same basic installation platform and can be replaced. The annular blade cascade test section is mainly used for subsonic tests of booster blades and turbine blades, the fan-shaped blade cascade test section is used for subsonic tests of booster blades and turbine blades, and the plane blade cascade test section is mainly used for sub-supersonic tests of booster blades and turbine blades. Taking into account the differences in the structural morphology of the three blade cascade test sections, in order to facilitate rapid replacement, the convergent sections and nozzles corresponding to the annular blade cascade test section and the fan-shaped test section are an integrated structure. The convergent section outlet corresponding to the plane blade cascade test section is connected to the nozzle inlet through a flange, and the centering stop is positioned. The nozzle adopts a two-dimensional nozzle flow channel, which is composed of a nozzle box and a trolley. The nozzle box is used to install and fix the nozzle block, and the nozzle trolley is used to support the nozzle box. Figure 7 As shown; the cascade test section includes an intake section and an exhaust section, and inlet and outlet measurement sections are respectively set up, and total pressure probes, total temperature probes and static pressure measurement points are arranged.

[0024] The exhaust system is connected to the outlet of the cascade test section, such as Figure 2 , 4As shown, it includes a horizontal exhaust collector 22 fixed in the horizontal direction and a mobile exhaust collector 21 movable in the circumferential direction. The former meets the exhaust requirements of the annular blade and fan blade tests and the plane blade supersonic test, and the latter focuses on meeting the exhaust requirements of the plane blade test section subsonic supersonic blade test and turbine blade test; both exhaust collectors are circular convergent structures; the movable exhaust collector is fixed on an arc guide rail and can move steplessly along the arc guide rail, and the corresponding center angle of the arc guide rail is greater than the range of change of the outlet airflow angle of the blade test section; the horizontal exhaust collector and the mobile exhaust collector are each connected to a section of the pipeline and connected to the same exhaust silencer tower 23, which adopts a matrix type air intake silencer element; the rectangular tube truss is made of carbon steel profiles (rust-proof treatment). The silencer element matrix unit body is made by welding. The blockage area accounts for 56% of the total air intake cross-section; the silencer device has no rust, shedding and emission of foreign matter such as mounting parts, fibers, dust and harmful substances.

[0025] Therefore, based on the above structure, the specific working principle of the annular cascade performance tester proposed in the present invention is as follows: open the gate valve on the main gas path, send the gas into the intake system, adjust the opening of the three groups of pressure regulating valves and fine adjustment valves on the large and small intake pipes 11, 12 and the exhaust pipe 10 respectively or synchronously, and the intake flow and pressure can be controlled. The fluid with changed parameters is transported through the straight pipe section 13, decelerated and pressurized in the diffusion section 14, stabilized in the stable section 15, and then sent to the cascade test section 17 through the convergent section 16 and the nozzle, and a flow field that meets the cascade test requirements is formed at the cascade test section; the basic installation platform of the cascade test section The tested blade cascade (annular blade cascade, fan-shaped blade cascade, plane blade cascade) is installed on the base installation platform, and the tested blade cascade rotates with the turntable on the basic installation platform to simulate normal working conditions, while the probes and moving measuring mechanisms arranged at the blade cascade test section measure a series of parameters such as velocity field and airflow deflection angle, and the acquired parameters can reflect the aerodynamic performance of the blade cascade; and the movable exhaust collector 22 in the exhaust system is fixed on an arc guide rail, which can be moved steplessly along the arc guide rail, and the corresponding center angle of the arc guide rail is greater than the variation range of the airflow angle at the outlet of the blade cascade test section, ensuring that the gas discharged from the blade cascade test section can be completely recovered.

[0026] In summary, the present invention is based on the above structure and the principle of Mach number similarity, with compressed air as the medium, and realizes the blowing test of annular blades, fan-shaped blades and plane blades under different Mach numbers through the corresponding convergent section 16 and the nozzle; by replacing the convergent section, the nozzle and the test section accordingly, it can have one of the three test functions of annular blades, fan-shaped blades and plane blades; each probe measures the flow field parameters of the blade test section, wherein the measurement of the velocity field is mainly divided into the inlet airflow velocity and flow direction measurement of the test section and the velocity measurement in the test section; the inlet velocity measurement of the test section adopts the method of measuring the wall static pressure to calculate the Mach number; the flow direction and velocity measurement along the test section are divided into the static pressure measurement of the side wall of the grid plate and the space pressure measurement, and the space pressure measurement adopts the coordinate shifting mechanism to cooperate with the direction probe to measure, and the space airflow direction angle data is obtained at the same time.

[0027] Example 2

[0028] The present embodiment provides a boundary layer suction system for an annular cascade performance tester, including vacuum pumps 31, 32, a vacuum box 34, and a vacuum pipeline; the vacuum pumps 31, 32 are connected to the vacuum box 34 via an electric gate valve 33; the vacuum box branches out a plurality of suction branches connected to the boundary layer of the cascade test section; a regulating valve 35 and a flow meter 36 are provided on the suction branch, which are connected to the cascade test section; the suction branch is connected to the suction part of the cascade test section via a hose 37, and suction is performed to ensure the formation of a desired flow field. In the present embodiment, there are 8 suction branches branched out by the vacuum box, which are mainly used for The suction branches of the four walls of the cascade test section and the cascade surface (1 for the upper resident chamber, 2 for the lower resident chamber, 2 for the boundary layer suction of the test section side wall, 2 for the boundary layer suction of the cascade surface, and 1 for standby) are connected to the test section by a hose 37, and the pressure and suction volume of each suction branch are adjusted by a regulating valve 35; in this embodiment, two vacuum pumps 31 and 32 are provided. In order to better ensure the operation of the boundary layer suction system and prevent the two vacuum pumps connected to the vacuum box from affecting each other, separate gas circuits are used to communicate with the vacuum box respectively, and a gate valve is provided on them; the exhaust end of the vacuum pump is connected to the exhaust silencer tower.

[0029] The specific working mode of the boundary layer suction system is as follows:

[0030] When the annular cascade performance tester conducts a cascade performance test, each suction branch of the boundary layer suction system is connected to the cascade test section; the vacuum pump is started, the gate valve provided between the vacuum pump and the vacuum box is opened, and the regulating valves on each suction branch are opened accordingly, and the two vacuum pumps suction the boundary layer of the cascade test section along the separate gas path, the vacuum box, and the suction branch, and the flow rate and pressure at each suction point can be changed by adjusting the regulating valves on each suction branch, so as to achieve the purpose of forming a desired flow field in the cascade test section.

[0031] Example 3

[0032] In this embodiment, a cooling system for an annular blade performance tester is proposed, which includes an air source 41 and a distributor 45; the air source is connected to the distributor 45 through a gate valve 43 and a main air path, a pressure sensor and a temperature sensor 42 are provided between the air source and the gate valve, and a venting pipeline as a branch is provided on the main air path, the branch is connected to the exhaust silencer, and a venting pressure regulating valve 44 is provided on the branch; the distributor adopts a horizontal air storage tank, and 10 flange holes are provided on the straight pipe side of the tank body for connecting 10 cooling air branches, and the cooling air branches are connected to the blade test section through a hose 46, and a regulating valve 48 and a flow meter 47 are provided on the hose; the distributor is equipped with a safety venting valve and a sewage outlet, and pressure and temperature measuring points are set inside, and its specific working method is as follows:

[0033] The main air circuit gate valve of the cooling system is opened, and the cooling air provided by the air source is sent to the distributor 45. The distributor is mainly used to store compressed air of a certain pressure and maintain internal pressure balance to ensure that the outlet pressure of the cooling air branch is close to the same; the distributor sends the cooling air to each cooling air branch, adjusts the regulating valve 48 on the cooling air branch, and controls the cooling air flow of each cooling air branch; at the same time, the branch of the main air circuit also includes a bleed pipeline, which is provided with a bleed pressure regulating valve 44. The bleed pressure regulating valve is used to control the cooling air flow entering the distributor, and the pressure value in the distributor is controlled at the same time, thereby ensuring the control accuracy of the regulating valves of each branch to meet the needs of the turbine blade cooling test.

[0034] Example 4

[0035] The difference between this embodiment and the previous three embodiments is that this embodiment also includes a test system, an electrical control system and a management system, wherein the test system is responsible for measuring various parameters; the electrical control system is responsible for monitoring and controlling process equipment and electrical equipment; and the management system is responsible for information management of test and measurement and control equipment.

[0036] Obviously, the above examples are only examples for clearly illustrating the technical solutions of the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. An annular cascade performance tester, characterized in that: Including air intake system, exhaust system, boundary layer suction system, and cooling system; The air intake system includes an air intake pipeline, a straight pipe section, a diffusion section, a stabilizing section, a convergent section, a nozzle, and a blade cascade test section; the air intake pipeline includes large and small air intake pipes and an air discharge pipeline; the large and small air intake pipes and the air discharge pipeline are all connected to the same air supply trunk, on which a group of pressure regulating valves and fine adjustment valves connected in parallel are arranged; an air intake gate valve is arranged on the air supply trunk; the large and small air intake pipes are connected and joined by a three-way joint; the rear of the three-way joint is connected to a straight pipe section; the rear of the straight pipe section is connected to a conical diffusion section; the diffusion section is connected to a stabilizing section; the stabilizing section includes a rectifying section and a pressure stabilizing section; the pressure stabilizing section is connected to the convergent section; the convergent section is connected to the blade cascade test section through a nozzle; a basic installation platform is arranged at the blade cascade test section; the outlet of the blade cascade test section is connected to the exhaust system; the blade cascade test section includes an air intake section and an exhaust section, and inlet and outlet measurement sections are respectively arranged, and total pressure probes, total temperature probes and static pressure measurement points are arranged; The exhaust system comprises a horizontal exhaust collector fixed in the horizontal direction and a mobile exhaust collector movable in the circumferential direction; the mobile exhaust collector is fixed on an arc guide rail and can move steplessly along the arc guide rail; the horizontal exhaust collector and the mobile exhaust collector are each connected to a section of pipeline and are connected to the same exhaust silencer tower; The boundary layer suction system includes a vacuum pump, a vacuum box, and a vacuum pipeline; the vacuum pump is connected to the vacuum box via an electric gate valve; the vacuum box divides into a plurality of suction branches connected to the boundary layer of the cascade test section; The cooling air system comprises an air source and a distributor; the air source is connected to the distributor via a gate valve and a pipeline; the distributor is connected to the blade grid test section via a plurality of cooling branches.

2. The annular blade performance tester according to claim 1, characterized in that: The cascade test section includes an annular cascade test section, a fan-shaped cascade test section, or a plane cascade test section, all of which are adapted to the same basic installation platform.

3. The annular blade performance tester according to claim 2, characterized in that: The shape of the convergent section air outlet corresponding to the annular cascade test section is circular; the shape of the convergent section air outlet corresponding to the fan-shaped cascade test section is fan-shaped; and the shape of the convergent section air outlet corresponding to the plane cascade test section is rectangular.

4. The annular blade performance tester according to claim 3, characterized in that: The convergent section corresponding to the annular cascade test section and the fan-shaped test section is an integrated structure with the nozzle; the convergent section outlet corresponding to the plane cascade test section is connected to the nozzle inlet through a flange and positioned by a centering stop.

5. The annular blade performance tester according to claim 4, characterized in that: The nozzle adopts a two-dimensional nozzle flow channel and is composed of a nozzle box and a trolley. The nozzle box is used to install and fix the nozzle block, and the nozzle trolley is used to support the nozzle box.

6. The annular blade performance tester according to claim 1, characterized in that: The suction branch and the cooling branch are both provided with regulating valves and flow meters.

7. The annular blade performance tester according to claim 1, characterized in that: It also includes test systems, electrical control systems and management systems.

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