Blade structure for improving stability of air flow at inlet of air compressor

Abstract

The blade structure comprises a blade and a blade tail end structure, and the blade tail end structure comprises a blade extending boss extending from the tail end of the blade, a first cylinder, a second cylinder and a third cylinder. The diameter of the first cylinder and the diameter of the third cylinder are larger than the diameter of the second cylinder. A T-shaped circular truncated cone formed by a second cylinder and a third cylinder of the blade tail end structure is matched with a variable-diameter cylindrical groove in a central circular truncated cone of an air inlet cylinder, the variable-diameter cylindrical groove comprises a first cylindrical groove and a second cylindrical groove, and a T-shaped cylindrical groove formed by the first cylindrical groove and the second cylindrical groove is in clearance fit with the T-shaped circular truncated cone. The variable-diameter cylindrical groove is formed, the vibration amplitude of the blade is limited from the structure, and meanwhile, a certain gap is reserved between the third cylindrical groove and the second cylindrical groove to limit movement of the blade.

Description

Technical Field

[0001] The invention belongs to the field of compressor inlet blades, and in particular relates to a blade structure for improving the stability of compressor inlet airflow. Background Art

[0002] As one of the core components of the gas turbine, the compressor is responsible for providing high-pressure working fluid for the combustion chamber. The pressure, temperature, flow matching and airflow stability of the compressor outlet airflow directly determine the wide-operating stability of the combustion chamber. The blades at the compressor inlet can not only guide the airflow direction and control the airflow speed, but also adjust the blade angle according to different working conditions to improve the working performance of the compressor. However, most traditional blades are in the form of cantilever beams (one end is fixed and the other end is free), and are structurally unrelated to the intake cylinder. On the one hand, this causes stress concentration at the root of the blades, and on the other hand, the blades are prone to vibrate when rotating, causing the intake airflow to be distorted, affecting the combustion efficiency, and ultimately reducing the working efficiency of the entire machine. In more serious cases, it will endanger the safe operation of the entire machine.

[0003] The existing methods for improving the stability of the compressor inlet airflow are mostly divided into three types: the first is to improve the force of the blade by optimizing the shape and size of the blade, so that the force distribution of the airflow on the blade surface is more uniform. The second is to increase the thickness of the blade root and the reinforcement ribs to improve the bearing capacity of the blade root; the third is to use high-performance materials for the blade or use coating technology on its surface to optimize the mechanical properties of the blade. The present invention mainly improves the intake stability of the blade by adding a variable diameter cylindrical structure at the end of the blade and providing a variable diameter cylindrical groove on the intake cylinder to cooperate with it to form a simply supported beam structure. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a blade structure for improving the stability of the compressor inlet airflow, and adopts the following technical solutions: A blade structure for improving the stability of airflow at an air compressor inlet, comprising a blade and a blade tip structure, wherein the blade tip structure comprises a blade extension boss extending from the blade tip, a first cylinder, a second cylinder and a third cylinder, wherein the first cylinder, the second cylinder and the third cylinder are sequentially arranged on the side of the blade extension boss away from the blade tip, wherein the diameters of the first cylinder and the third cylinder are greater than the diameter of the second cylinder; a T-shaped cone formed by the second cylinder and the third cylinder of the blade tip structure cooperates with a reducing cylindrical groove on a central cone of an intake cylinder, wherein the reducing cylindrical groove comprises a first cylindrical groove and a second cylindrical groove, wherein a T-shaped cylindrical groove formed by the first cylindrical groove and the second cylindrical groove forms a clearance fit with the T-shaped cone; the reducing cylindrical groove is divided into two halves, wherein one half is arranged on the central cone of the intake cylinder, and the other half is arranged on a fan-shaped cover.

[0005] Furthermore, in order to ensure the installation of multiple blades, a plurality of variable diameter cylindrical grooves are arranged at intervals upward on the circumference of the central cone of the air intake cylinder, and a plurality of bolt holes are provided between the plurality of variable diameter cylindrical grooves. The fan-shaped cover is also provided with a plurality of corresponding variable diameter cylindrical grooves, and the two form a plurality of complete T-shaped cylindrical groove structures, and the central cone of the air intake cylinder is fixedly connected to the fan-shaped cover by bolts.

[0006] Furthermore, to ensure the normal use and stability of the blade, the first cylinder has a maximum diameter and a minimum thickness, the second cylinder has a minimum diameter and a maximum thickness, and the radius and thickness of the third cylinder are in the middle.

[0007] Compared with the prior art, the present invention has the following beneficial effects: A variable diameter cylindrical groove is set on the central circular table of the air inlet cylinder to limit the vibration amplitude of the blade from the structure itself. When the blade vibrates, the end of the blade will be close to the air inlet cylinder to reduce the amplitude. Since there is a certain gap between the third cylinder and the second cylindrical groove, it ensures that the blade will not get stuck when it moves up and down, and also limits the amplitude of the blade's up and down movement. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0009] Figure 1 A three-dimensional diagram of the blade of the present invention Figure 2 A three-dimensional diagram of the blade tip structure of the present invention Figure 3 A plan view of the blade tip structure of the present invention Figure 4 A three-dimensional view of the lower half of the intake cylinder of the present invention Figure 5 A three-dimensional view of the lower half of the fan-shaped cover of the present invention Figure 6 A partial enlarged view of the blade tip and the cylindrical groove according to the present invention Figure 7 This is a three-dimensional diagram of the assembly of the blade of the present invention In the accompanying drawings, the components represented by the reference numerals are listed as follows: 1-blade, 2-blade extension boss, 3-first cylinder, 4-second cylinder, 5-third cylinder, 6-reducing cylindrical groove, 7-intake cylinder center cone, 8-fan-shaped cover, 9-first cylindrical groove, 10-second cylindrical groove, 11-bolt hole. DETAILED DESCRIPTION

[0010] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0011] like Figure 1-Figure 3 As shown, a blade structure for improving the stability of the compressor inlet airflow is composed of a blade 1 and a blade end structure. The blade end structure is composed of a blade extension boss 2, a first cylinder 3, a second cylinder 4, and a third cylinder 5 from top to bottom; Figure 4 and Figure 5 As shown, the variable diameter cylindrical groove 6 is divided into two halves, which are respectively arranged on the central truncated cone 7 and the fan-shaped cover 8 of the air intake cylinder.

[0012] The blade extension boss 2 is an extension of the curved surface of the blade 1, but its width is only one-third of the curved surface, but its width is slightly larger than the diameter of the first cylinder 3; in the cylindrical structure, the first cylinder 3 has the largest radius but the smallest thickness; the second cylinder 4 has the smallest radius but the largest thickness; the third cylinder 5 has a radius larger than the second cylinder 4, but the thickness is second.

[0013] like Figure 6 As shown, the variable diameter cylindrical groove 6 is composed of a first cylindrical groove 9 and a second cylindrical groove 10, which cooperate with the second cylinder 4 and the third cylinder 5 at the end of the blade. The length of the second cylinder 4 is greater than the first cylindrical groove 9, but its radius is smaller than the cylindrical groove; the radius and length of the third cylinder 5 are both smaller than the second cylindrical groove 10, so as to prevent the blade from getting stuck when the blade moves up and down.

[0014] The central circular table 7 of the air inlet cylinder and the sector-shaped cover 8 are connected by 8 bolts passing through bolt holes 11, and the bolt holes 11 are arranged between the two diameter-changing grooves.

[0015] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0016] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A blade structure for improving the stability of airflow at the compressor inlet, characterized in that: It includes a blade and a blade end structure, wherein the blade end structure includes a blade extension boss extended from the blade end, a first cylinder, a second cylinder and a third cylinder, the first cylinder, the second cylinder and the third cylinder are sequentially arranged on the side of the blade extension boss away from the blade end, the diameter of the first cylinder and the diameter of the third cylinder are greater than the diameter of the second cylinder; the T-shaped cone formed by the second cylinder and the third cylinder of the blade end structure cooperates with the variable diameter cylindrical groove on the central cone of the intake cylinder, the variable diameter cylindrical groove includes a first cylindrical groove and a second cylindrical groove, the T-shaped cylindrical groove formed by the first cylindrical groove and the second cylindrical groove forms a clearance fit with the T-shaped cone; the variable diameter cylindrical groove is divided into two halves, one half is arranged on the central cone of the intake cylinder, and the other half is arranged on the fan-shaped cover.

2. A blade structure for improving the stability of compressor inlet airflow according to claim 1, characterized in that: A plurality of reducing cylindrical grooves are arranged at intervals upward on the circumference of the central cone of the air intake cylinder, and a plurality of bolt holes are arranged between the plurality of reducing cylindrical grooves. The fan-shaped cover is also provided with a plurality of reducing cylindrical grooves corresponding thereto, and the two form a plurality of complete T-shaped cylindrical groove structures, and the central cone of the air intake cylinder is fixedly connected to the fan-shaped cover by bolts.

3. A blade structure for improving the stability of compressor inlet airflow according to claim 1 or 2, characterized in that: The first cylinder has the largest diameter and the smallest thickness, the second cylinder has the smallest diameter and the largest thickness, and the radius and thickness of the third cylinder are in the middle.

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