CN111734679A

CN111734679A - Aeroengine compressor inner casing with air vent and machining method thereof

Info

Publication number: CN111734679A
Application number: CN202010633318.9A
Authority: CN
Inventors: 关婷婷; 薛雨洲; 陈少俊
Original assignee: China Hangfa Changzhou Lanxiang Machinery Co ltd
Current assignee: China Hangfa Changzhou Lanxiang Machinery Co ltd
Priority date: 2020-07-02
Filing date: 2020-07-02
Publication date: 2020-10-02

Abstract

The invention relates to an aeroengine compressor inner casing with a vent hole and a processing method thereof, the aeroengine compressor inner casing with the vent hole comprises an inner casing body, a plurality of waist-shaped vent holes are uniformly distributed on the side wall of the middle part of the inner casing body along the circumferential direction, and the air flow flowing along the inner wall of the inner casing is guided, so that the air flow can be shunted to the outside of an air flow channel of the aeroengine inner casing at the waist-shaped vent holes, the interstage venting of the aeroengine is realized, and the air flow is ensured not to be blocked in the air flow channel.

Description

Aeroengine compressor inner casing with air vent and machining method thereof

Technical Field

The invention relates to the technical field of aeroengine parts, in particular to an aeroengine compressor inner casing with a vent hole and a processing method thereof.

Background

The compressor inner casing is used in an aeroengine and belongs to one of important parts in a compressor flow passage part. Compressor stabilization has been one of the major points of aeroengine research from the beginning of the 20 th 20 s aviation gas turbine engines to today. When the engine works, airflow flows out of the axial flow compressor and enters a channel formed by a casing and a rotor of the centrifugal compressor in the compressor, the airflow speed and the pressure in the compressor are further increased, when the rotating speed deviates from the designed rotating speed greatly, the working conditions of the front stage and the rear stage of the compressor deviate from the optimal design conditions due to the fact that the changing proportion of the rotating speed and the sucked airflow is not coordinated, the attack angle of each stage of blade deviates from the optimal value, the performance of each stage is reduced, the compressor surging is caused seriously, the working matching of the front stage and the rear stage of the compressor is not coordinated, the performance of the whole engine is deteriorated, and the compressor surging is the airflow oscillation phenomenon of low frequency and high amplitude generated along the axial direction of the compressor. The surge phenomenon of the compressor can cause strong mechanical vibration and over-temperature of a hot end of the engine, the engine is seriously damaged in a very short time, and the compressor cannot be allowed to enter a surge area to work under any working state. If geometric adjustment measures are not adopted, partial rotation speed performance deterioration phenomena often occur, which are shown in that the local concave part of a surge boundary line is formed, the characteristic line flow is reduced, the surge point pressure ratio is reduced, the efficiency is generally reduced, and the engine surge can occur in further development.

Disclosure of Invention

The invention aims to provide an aeroengine compressor inner casing with an air vent and a processing method thereof, wherein the aeroengine compressor inner casing is simple in structure and capable of avoiding surge.

In order to solve the technical problem, the aeroengine compressor inner casing with the air bleed holes comprises an inner casing body, wherein a plurality of waist-shaped air bleed holes are uniformly distributed on the side wall of the middle part of the inner casing body along the circumferential direction, and the air flow flowing along the inner wall of the inner casing is guided, so that the air flow can be divided to the outside of an air flow channel of the inner casing of the compressor at the waist-shaped air bleed holes, the interstage air bleed of the compressor is realized, and the air flow cannot be blocked in the air flow channel.

Furthermore, the normal direction of the waist-shaped air release hole forms an included angle of 45 degrees with the axial direction of the casing in the compressor, namely the normal direction of the waist-shaped air release hole forms an included angle of 45 degrees with the airflow direction.

Furthermore, two ends of the waist-shaped air vent are arranged in a semicircular shape.

Furthermore, the number of the waist-shaped air release holes is 6, and the waist-shaped air release holes are uniformly distributed on the same circumference of the side wall of the middle part of the inner casing body.

The processing method of the aeroengine compressor inner casing with the vent hole comprises the following steps: drawing a complete circumference on the inner wall of a casing in a compressor, cutting 6 arcs with 12 degrees on the circumference, and uniformly distributing the 6 arcs on the circumference; at two ends of each circular arc, two end points of each circular arc are respectively taken as circle centers to form semi-circles with the radius of R along the inner wall of the compressor casing, corresponding end points of the two semi-circles are connected by making curves along the inner wall of the compressor casing, and the semi-circles and the curves form a waist-shaped air release hole in an enclosing mode.

The invention has the technical effects that: (1) compared with the prior art, the aero-engine compressor casing with the air vent is provided with six waist-shaped air vents on the inner wall of the compressor casing, so that air flow in the compressor can be subjected to interstage air release at the open hole, and the air flow is prevented from being blocked in a channel; the compressor inner casing is used as an important part of the engine, the engine surge is effectively prevented on the basis of meeting the use requirement of the compressor inner casing, the stable work of the engine is ensured, after the compressor inner casings with waist-shaped vent holes are assembled on a plurality of engines, the engines do not surge again, and the improvement effect is obvious; (2) the normal direction of the waist-shaped air vent and the airflow direction form an included angle of 45 degrees, and the waist-shaped air vent is obliquely arranged, so that the airflow can be quickly discharged to the outside of an engine inner box when flowing through the waist-shaped air vent, and the exhaust of the airflow is favorably accelerated; (3) the two ends of the waist-shaped vent are semicircular, so that the air flow is convenient to guide when flowing through the waist-shaped vent, and the air flow can be discharged out of the engine inner casing quickly.

Drawings

The invention is described in further detail below with reference to the drawings of the specification:

fig. 1 is a schematic perspective view of a casing in a compressor of an aircraft engine with bleed holes according to the present invention;

FIG. 2 is a schematic cross-sectional view of the compressor case of an aircraft engine having bleed holes in accordance with the present invention;

FIG. 3 is a schematic cross-sectional view taken along the line P-P in FIG. 2;

FIG. 4 is a schematic cross-sectional view taken along the direction F-F in FIG. 3;

in the figure: the air vent comprises a waist-shaped air vent 1, a first arc line 11, a second arc line 12, a first waist line 13, a second waist line 14, a middle side wall 2, an inner casing body 3 and an airflow channel 4.

Detailed Description

Example 1

As shown in fig. 1 to 4, the aero-engine compressor inner casing with bleed holes of the present embodiment includes an inner casing body 3, wherein 6 waist-shaped bleed holes 1 are uniformly distributed on a middle side wall 2 of the inner casing body 3 along a circumferential direction, and the 6 waist-shaped bleed holes 1 are disposed on a same circumference; the normal direction of each waist-shaped air vent 1 forms an included angle of 45 degrees with the axial direction of a casing in the compressor, namely the normal direction of each waist-shaped air vent 1 forms an included angle of 45 degrees with the airflow direction; two ends of each waist-shaped vent hole 1 are arranged in a semicircular shape; when the air compressor is used, the waist-shaped air vent 1 guides airflow flowing along the inner wall of the inner casing, so that the airflow can be divided to the outside of an airflow channel 4 of the inner casing of the air compressor at the waist-shaped air vent 1, interstage air release of the air compressor is realized, and the airflow is ensured not to be blocked in the airflow channel 4.

Example 2

The method for processing the casing in the compressor of the aero-engine with the bleed hole, which is described in embodiment 1, comprises the following steps: drawing a complete circumference on the inner wall of a casing in a compressor, cutting 6 arcs with 12 degrees on the circumference, and uniformly distributing the 6 arcs on the circumference; at the both ends of each circular arc, use two endpoints of each circular arc respectively as the centre of a circle and do the semicircle that the radius is R along the compressor machine casket inner wall, be first pitch arc 11 and second pitch arc 12 respectively, do the curve along the compressor machine casket inner wall and connect the corresponding endpoint of two semicircles, be connected the upper portion endpoint of first pitch arc 11 and the upper portion endpoint of second pitch arc 12 through first curve 13 promptly, be connected the lower part endpoint of first pitch arc 11 and the lower part endpoint of second pitch arc 12 through second curve 14, enclose into waist shape gas release 1 by first pitch arc 11, first curve 13, second pitch arc 12, second curve 14.

It should be understood that the above examples are only for clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And such obvious variations or modifications which fall within the spirit of the invention are intended to be covered by the scope of the present invention.

Claims

1. The aeroengine compressor inner casing with the air bleed holes is characterized by comprising an inner casing body, wherein a plurality of waist-shaped air bleed holes are uniformly distributed on the side wall of the middle part of the inner casing body along the circumferential direction, and the air flow flowing along the inner wall of the inner casing is guided, so that the air flow can be distributed outside an air flow channel of the compressor inner casing at the waist-shaped air bleed holes.

2. The aero-engine compressor casing with the bleed holes as defined in claim 1, wherein a normal direction of the waist-shaped bleed holes forms an included angle of 45 degrees with an axial direction of the compressor casing, that is, a normal direction of the waist-shaped bleed holes forms an included angle of 45 degrees with an air flow direction.

3. The aero-engine compressor casing with bleed holes as defined in claim 2, wherein the waist-shaped bleed holes are arranged in a semicircular shape at both ends.

4. The aero-engine compressor casing with bleed holes according to claim 2 or 3, wherein the number of the kidney-shaped bleed holes is 6, and the 6 kidney-shaped bleed holes are uniformly distributed on the same circumference of the side wall of the middle portion of the inner casing body.

5. The method for processing the compressor casing of the aero-engine with the bleed hole as claimed in claim 4, wherein the method comprises the following steps: drawing a complete circumference on the inner wall of a casing in a compressor, cutting 6 arcs with 12 degrees on the circumference, and uniformly distributing the 6 arcs on the circumference; at two ends of each circular arc, two end points of each circular arc are respectively taken as circle centers to form semi-circles with the radius of R along the inner wall of the compressor casing, corresponding end points of the two semi-circles are connected by making curves along the inner wall of the compressor casing, and the semi-circles and the curves form a waist-shaped air release hole in an enclosing mode.