CN114705413A - Blade mounting structure, method and application using mainstream aerodynamic fastening - Google Patents

Abstract

The invention discloses a blade mounting structure fastened by using main flow aerodynamic force, a method and application thereof, and relates to the technical field of blade grid test blade mounting. The key points of the technical scheme are as follows: the test bench is equipped with the mount pad, and is rotatory after inserting the wall with the blade base, utilizes mainstream to make the blade fixed to the aerodynamic force of blade, need not other parts and instrument, and the installation is simple, can shorten blade installation time.

Description

Blade mounting structure, method and application using mainstream aerodynamic fastening

technical field

The invention belongs to the technical field of blade cascade test blade installation, and in particular, designs a blade installation structure, installation method and application thereof which are fastened by mainstream aerodynamic forces.

Background technique

Gas turbine engine is a thermal power plant based on Brayton cycle, which has been widely used in modern military and industry due to its strong output power and high thermal efficiency. The indispensable compressor and turbine components in the engine are both impellers, which require blades to decelerate, diffuse or contract passages, accelerate airflow, reduce temperature or perform work; and in blade-related tests, whether it is for stationary blades (or Guide vanes) or moving vanes, the static cascade test is an important test form for designing and verifying the relevant performance of the blade. In the test, the blades need to be installed and fixed in the cascade channel under the mainstream conditions.

At present, the fixing method of static cascade test blades is generally flange bolt connection or tenon connection. Among them, the flange bolt connection method requires a large number of bolt structures, which makes the process of replacing the test piece time-consuming and laborious. In addition, some static cascade tests are performed in the cavity, and the relatively compact test bench cavity cannot provide bolts. The spanner extends into the necessary space during installation. The tenon types of tenon connection include dowel tenon, axial dovetail tenon, annular dovetail tenon, and fir tree tenon. During the working process, the aerodynamic force will move the blade along the groove, so the tenon connection needs a locking structure. The locking structure will increase the number of parts, and the locking structure often uses the plastic deformation of its own structure to provide the force required for installation and fixation, which is not desirable in the static cascade test that requires repeated blade replacement. In the cascade test, the time to replace the blades is often a large proportion in the overall test cycle, and the fixing effect of the blades directly determines the safety degree during the test process and the reliability of the test results.

In addition, the prior art such as Chinese patent application, its application number: CN2019104427051, publication number: CN110145372A, discloses a steam turbine rotor fork blade installation structure, which relates to the technical field of steam turbine blade installation, and aims to solve the problem of inability to install traditional blades. To eliminate the problem of installation clearance, the main points of the technical solution are: including a rotor and a fork-shaped blade connected to the rotor, a mounting seat is connected to the side wall of the rotor, and an annular fork-shaped wheel groove is formed on the mounting seat and the rotor coaxially. A plurality of intermediate blades are slidably clamped in the fork-shaped wheel groove, the side wall of the fork-shaped wheel groove is provided with a wheel groove along the radial direction of the rotor, the end blade is passed through the wheel groove, and the wheel groove is provided with a Locking assembly for locking the last blade. Application No.: CN2017108308230, Publication No.: CN107725117A, discloses a stator blade mounting structure that can be applied to ground gas turbines, aero-engines and other fields, including a stator blade with a pressure plate, an inner and outer ring lightweight elastic member, an inner and outer ring casing and Clamps for outer ring pressure plate. Through the above parts, the single-piece detachable function of the stator blade can be realized. Due to the use of light elastic parts, the cold state interference between the light elastic parts and the inner and outer ring profiles of the blade can be used to realize the assembly and positioning of the entire ring of stator blades. . In the assembled state, the assembly has a certain rigidity, and can transmit the aerodynamic torque of the stator blade to the corresponding position on the mounting edge of the casing.

However, the above-mentioned prior art is complicated to install, which is not conducive to installation and positioning. Therefore, it is necessary and meaningful to improve the blade installation structure, reduce the number of parts as much as possible, simplify the installation steps, and reduce the space required for installation under the premise of ensuring reliability.

SUMMARY OF THE INVENTION

In order to improve the test efficiency of the stationary blade cascade and realize blade installation in a limited space, the present invention proposes a blade installation structure and an installation method using mainstream aerodynamic fastening, which has the advantage of simple installation.

The object of the present invention is achieved through the following technical solutions:

A blade installation structure using mainstream aerodynamic fastening, comprising blades, a test bench, a blade base, and a mounting seat, and is characterized by:

The blade base and the mounting seat are in contact with each other, and play the role of connecting the blade and the test bench to ensure that the blade can be fixed on the test bench during the test process. The axis of the incomplete circular sheet coincides with the axis of the cylinder, and the intersection of the diagonal lines of the incomplete rectangular sheet is on the axis of the cylinder, so that the incomplete rectangular sheet can be rotated around the axis after being inserted into the test bench.

The mounting seat is provided with an entry cavity, a rotation cavity and a positioning cavity. The rotating cavity is formed through the mounting seat by the top view shape of the incomplete wafer, so the incomplete wafer is coincident with the axis of the rotating cavity. The entry cavity is formed by the downward through groove, the arc belt groove and the positioning groove opened in the mounting seat. The downward through groove has the same shape as the end of the incomplete rectangular sheet, so that the incomplete rectangular sheet can be inserted into the arc belt groove. The positioning cavity is a circular arc slot opened in the mounting seat.

Preferably, the outer diameter of the circular arc groove of the entering cavity and the positioning cavity is the same as the diagonal length of the incomplete rectangular sheet, and the height of the circular arc groove is the same as the thickness of the incomplete rectangular sheet.

Preferably, after the blade is inserted, the incomplete rectangular sheet can rotate in the arc-shaped groove, and cannot move up and down along the normal direction of the plane of the test bed, so as to realize the fixation in the axial direction.

Preferably, the distance between the upper surface of the arc groove and the lower surface of the cascade channel is the same as the thickness of the incomplete disc. When the side of the incomplete rectangular sheet is in contact with the side of the positioning groove and the side of the positioning cavity respectively, the blade is just placed in the installation position, and at this time, the incomplete circular sheet and the incomplete rectangular sheet are flush with the exit of the test bench.

Preferably: after the blade is installed, the upper surface of the blade base and the cascade channel, that is, the lower surface of the inner surface of the test bench, are on the same plane, and the cascade channel is flat; the blade base does not protrude from the test bench on the trailing edge side of the blade, which does not affect the test export conditions.

Preferably, the diameter of the incomplete disc is greater than the distance between any two points on the test airfoil, and the bottom surface of the blade can be completely included in the top view.

By adopting the above-mentioned technical solution, it is possible to reserve the position inside the blade where the air path and the line need to be arranged.

The above technical solutions need to be realized through the following technical solutions:

An installation method of a blade installation structure using mainstream aerodynamic fastening, comprising the following steps:

S1, insert the blade from the bottom of the test bench. During the insertion process, the axis of the incomplete wafer coincides with the axis of the rotating cavity, one side of the incomplete rectangular piece is aligned with the shape of the downward through groove, and the insertion direction is the normal direction of the test bench; until The upper surface of the incomplete rectangular sheet is in contact with the upper surface of the circular arc slot, and the side surface of the incomplete circular sheet is in contact with the side surface of the rotating cavity at this time, and the upper surface of the incomplete circular sheet is aligned with the lower surface of the cascade channel.

S2, rotate the blade along the cylinder axis until the side surfaces of the incomplete rectangular sheet are in contact with the side surfaces of the positioning groove and the positioning cavity respectively.

After the blade is installed using the above technical solution, during the test, the mainstream gas flows along the blade. According to the aerodynamic principle of the blade, the pressure on the pressure side of the blade is greater than the pressure on the suction side. According to the shape of the blade, by setting the position of the cylinder axis, The aerodynamic force of the mainstream gas on the blade can generate the same torque as the installation direction, so that the side of the incomplete rectangular sheet is in continuous contact with the side of the positioning groove and the side of the positioning cavity, so that the blade base cannot rotate in the opposite direction of installation and falls from the entry cavity, so as to realize Fasten. At the same time, the incomplete rectangular sheet is in contact with the side of the positioning groove, and the incomplete circular sheet is in contact with the side wall of the rotating cavity, so that the blade cannot fall backward from the test bench along the mainstream direction.

The above technical solution is achieved by the following arrangements: the entry cavity is on the side of the blade basin after the blade is installed, and the positioning cavity is on the back side of the blade after the blade is installed.

The invention also discloses a blade mounting structure that applies the above-mentioned mainstream aerodynamic fastening to the fixing of stationary blade cascade test blades in a gas turbine engine.

The invention also discloses a method for installing and fixing the above-mentioned blade installation structure using the mainstream aerodynamic force to be applied to the installation and fixing process of the stationary blade cascade test blade in the gas turbine engine.

Beneficial effects:

When the blade is inserted into the test bench, the incomplete rectangular sheet of the blade base is inserted into the circular arc slot through the downward through groove, and the incomplete circular sheet is used to coincide with the axis of the rotating cavity, and the wall surface contacts to achieve radial positioning. After the blade is rotated as a whole, the circular The thickness of the arc-slot groove is the same as that of the incomplete rectangular sheet to realize axial positioning and fixation, and the circumferential positioning is realized by using the incomplete rectangular sheet to contact the side of the positioning groove and the side of the positioning cavity. After the blade is installed, the aerodynamic force of the mainstream is used to fix the blade, no other parts and tools are required during the installation process, and the installation time is short.

Description of drawings

FIG. 1 is an axonometric view of the test bench after the installation of the blade of the present invention is completed.

Figure 2 is an axonometric view of the test bench in the present invention.

Figure 3 is an axonometric view of the blade of the present invention.

FIG. 4 is a rear view of the test bench after the installation of the blade of the present invention is completed.

FIG. 5 is a D-D cross-sectional view of the test bench of the present invention (without blades) in FIG. 4 .

In the picture:

1. Blade; 2. Test stand; 3. Blade base; 4. Mounting seat; 5. Incomplete disc; 6. Incomplete rectangular sheet; 7. Cylinder; 8. Entry cavity; 9. Rotating cavity; 10. Positioning Cavity; 11. Downward through groove; 12. Positioning groove; 13. Leaf basin side; 14 Leaf dorsal side

Detailed ways

The present invention will be described in more detail below in conjunction with the accompanying drawings:

Example 1

1-5, this embodiment provides a blade installation structure and installation method using mainstream aerodynamic fastening, the installation structure mainly includes a blade 1, a test bench 2, a blade base 3, and a mounting seat 4.

As shown in FIG. 1 and FIG. 4 , the blade base 3 and the mounting seat 4 are in contact with each other, and play the role of connecting the blade 1 and the test stand 2 .

As shown in FIG. 3 , the blade base 3 is formed by superimposing an incomplete circular sheet 5, an incomplete rectangular sheet 6, and a cylinder 7. The axis of the incomplete circular sheet 5 coincides with the axis of the cylinder 7, and the incomplete rectangular sheet 6 is diagonally opposite. The intersection of the lines is on the axis of the cylinder 7 . In the example, the thickness of the incomplete circular sheet 5 is 5 mm, and the thickness of the incomplete rectangular sheet 6 is 10 mm.

As shown in FIG. 2 and FIG. 4 , the mounting base 4 is provided with an entry cavity 8 , a rotation cavity 9 and a positioning cavity 10 . The rotating cavity 9 is formed through the shape of the top view of the incomplete wafer 5. Combined with the characteristics of the blade base 3 shown in FIG. 3, the axes of the incomplete wafer 5, the cylinder 7 and the rotating cavity 9 are all coincident, so that the blade 1 and the blade base 3 are inserted The test stand 2 can then be rotated around this axis. The entry cavity 8 is on the basin side 13 of the blade 1 after installation, and the positioning cavity 10 is on the back side 14 of the blade after the blade 1 is installed. Make the main aerodynamic force to the blade in the same direction as the installation direction.

As shown in FIG. 5 , the entry cavity 8 is formed by the downward through groove 11 , the arc belt groove and the positioning groove 12 in the mounting seat 4 . The downward through groove 11 has the same shape as the end of the incomplete rectangular sheet 6 , so that the incomplete rectangular The sheet 6 can be inserted into the circular arc belt groove. The positioning cavity 10 is provided with a circular arc groove in the mounting seat.

The distance between the upper surface of the circular arc grooved groove of the entry cavity 8 and the positioning cavity 10 and the lower bottom surface of the cascade channel is 5 mm, which is the same as the thickness of the incomplete wafer 5. Therefore, after the installation of the blade 1 is completed, the upper surface of the blade base 3 can be just right. The bottom surface of the cascade channel is filled, the cascade channel is flat, and the installation structure will not affect the test flow field. The outer diameters of the two circular arc grooves are equal to the diagonal length of the incomplete rectangular sheet 6 , and the height of the circular arc grooves is 10 mm, which is the same as the thickness of the incomplete rectangular sheet 6 . After the blade is inserted, the incomplete rectangular sheet 6 can rotate in the arc slot, and cannot move up and down in the axial direction, so as to realize the fixation in the axial direction.

When the incomplete rectangular sheet 6 is in contact with the side of the positioning groove 12 and the side of the positioning cavity 10, the blade is just placed in the installation position, and the incomplete circular sheet 5 and the incomplete rectangular sheet 6 are flush with the exit of the test bench 2, and the installation structure does not affect the test. export conditions.

The incomplete wafer 5 can completely include the bottom surface of the blade 1, and can reserve the position required for the arrangement of the air circuit and the circuit inside the blade.

Embodiment 2

An installation method of a blade installation structure using mainstream aerodynamic fastening, comprising the following steps:

S1, insert the blade 1 from the bottom of the test bench 2. During the insertion process, the insertion direction is the normal direction of the lower bottom surface of the blade cascade. In this example, the trailing edge of the blade 2 faces the left front, so that the incomplete rectangular sheet 6 is in the blade 2. The shape of the trailing edge side is aligned with the shape of the downward penetration groove 11, so that the incomplete rectangular sheet 6 can be inserted into the circular arc groove through the downward penetration groove 11. At this time, the upper surface of the incomplete rectangular sheet and the circular arc groove upper surface are Contact, the upper surface of the incomplete wafer is flush with the lower surface of the cascade channel, the side of the incomplete wafer is in contact with the side of the rotating cavity, and the axis of the incomplete wafer 5 coincides with the axis of the rotating cavity 9, and the radial fixation is realized by the above.

S2, in the example, the blade 1 and the blade base 3 are rotated as a whole along the axis of the cylinder 7 in a counterclockwise direction in the top view. When the rotation angle is 90 degrees, the side surfaces of the incomplete rectangular sheet 6 are respectively connected with the side surfaces of the positioning grooves 12 and the positioning cavity. 10 side contacts. During the rotation process, the axial positioning of the blade can be achieved by using the same thickness of the circular arc groove as that of the incomplete rectangular sheet 6 .

By adopting the above technical solution, after the blade 2 is installed, during the test process, the aerodynamic force of the mainstream gas to the blade 1 gives the blade 1 the same torque as the installation direction, in the example, the top view is counterclockwise, so that the incomplete rectangular sheet 6 is in continuous contact with the side surface of the positioning groove 12 and the side surface of the positioning cavity 10, so that the blade base 3 cannot rotate against the installation direction, and falls from the entry cavity 8 to achieve circumferential positioning, so that the position of the blade is completely fixed and fastening is achieved. The incomplete rectangular sheet 6 is in contact with the side of the positioning groove 12, and the incomplete circular sheet 5 is in contact with the side wall of the rotating cavity 6, so that the blade 1 cannot fall backward from the test bench 2 along the mainstream direction.

The embodiments of this specific embodiment are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore: all equivalent changes made according to the structure, shape and principle of the present invention should be covered in within the protection scope of the present invention.

Claims (8)

1. The utility model provides an utilize blade mounting structure of mainstream aerodynamic fastening, includes blade (1), test bench (2), blade base (3), mount pad (4), its characterized in that: blade base (3) are in blade (1) below, and mount pad (4) set up in test bench (2), blade base (3) form including incomplete disc (5), incomplete rectangle piece (6), cylinder (7) stack, and the axis of incomplete disc (5) and cylinder (7) axis coincidence, the nodical point of incomplete rectangle piece (6) diagonal are on cylinder (7) axis, and incomplete disc (5) diameter is greater than the distance of arbitrary two points on the experimental leaf type.

2. A blade mounting structure secured by mainstream aerodynamic forces as claimed in claim 1, wherein: the mounting seat (4) is provided with an inlet cavity (8), a rotating cavity (9) and a positioning cavity (10); the inlet cavity (8) is formed by arranging an arc-shaped belt groove, a downward through groove (11) and a positioning groove (12) in the mounting seat (4), and the shape of the downward through groove (11) is the same as that of the tail end of the incomplete rectangular sheet (6); the rotating cavity (9) is formed by stretching the shape of the incomplete wafer (5) in a top view along the normal direction; the positioning cavity (10) is an arc-shaped belt groove formed in the mounting seat (4); the outer diameter of the circular arc belt groove of the entering cavity (8) and the positioning cavity (10) is the length of the diagonal line of the incomplete rectangular sheet (6), and the thickness of the circular arc belt groove is the same as that of the incomplete rectangular sheet (6).

3. A blade mounting structure secured with mainstream aerodynamic forces as defined in claim 2, wherein: the inlet cavity (8) is arranged on the blade basin side (13) after the blade (1) is installed, and the positioning cavity (10) is arranged on the blade back side (14) after the blade (1) is installed.

4. The blade mounting structure fastened by mainstream aerodynamic force according to claim 1, wherein after the mounting is completed, the incomplete round sheet (5) and the incomplete rectangular sheet (6) are mounted and flush with the outlet of the test bed (2); the thickness of the incomplete wafer (5) is the same as the distance from the upper surface of the circular-arc groove to the lower surface of the blade grid channel.

5. A method for installing and fixing a blade installation structure fastened by using main flow aerodynamic force is characterized in that: comprises the following steps

S1, inserting the blade (1) from the lower part of the test bed (2), wherein in the inserting process, the axis of the incomplete wafer (5) is overlapped with the axis of the rotating cavity (9), and the incomplete rectangular sheet (6) is aligned with the downward through groove (11); until the upper surface of the incomplete rectangular sheet (6) is contacted with the upper surface of the circular arc groove, the upper surface of the incomplete wafer (5) is aligned with the lower surface of the cascade channel, and the side surface of the incomplete wafer (5) is contacted with the side surface of the rotary cavity (9);

and S2, rotating the blade (1) along the cylindrical axis until the incomplete rectangular sheet (6) contacts with the side surface of the positioning groove (12) and the side surface of the positioning cavity (10), and placing the blade at the right mounting position.

6. A method of installation and securement of a blade mounting structure utilizing mainstream aerodynamic fastening as claimed in claim 5, wherein: after the steps are carried out, in the test process, the aerodynamic force of the main flow gas on the blade (1) gives the same torque to the blade (1) in the mounting direction, so that the incomplete rectangular sheet (6) is continuously contacted with the side surface of the positioning groove (12) and the side surface of the positioning cavity (10), the blade base (3) cannot rotate in the reverse mounting direction and falls from the inlet cavity (8), and the fixation is realized; meanwhile, the incomplete wafer (5) is in contact with the side wall of the rotating cavity (9), and the incomplete rectangular sheet (6) is in contact with the side face of the positioning groove (12), so that the blade (1) cannot fall off from the test bed (2) along the main flow direction.

7. The use of a blade mounting structure as claimed in any of claims 1 to 4 for fastening with mainstream aerodynamic forces for the fastening of stationary cascade test blades in gas turbine engines.

8. The method for mounting and fixing a blade mounting structure fastened by means of mainstream aerodynamic force as recited in any one of claims 5 to 6 is applied to the mounting and fixing process of a stationary cascade test blade in a gas turbine engine.

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