阅读说明：本技术 一种轴向缝式处理机匣 (Axial seam type treatment casing ) 是由 杜娟 张千丰 李继超 张宏武 于 2019-12-16 设计创作，主要内容包括：本发明提供了一种轴向缝式处理机匣,属于压气机技术领域。其中处理机匣包括：压气机转子的动叶片设置于处理机匣内,动叶片的边缘朝向处理机匣的内壁；在处理机匣的内壁对应动叶片边缘上游至下游的区域开设有多条沿处理机匣的轴向延伸的缝式结构,多条缝式结构沿处理机匣的周向均匀、错位分布。本发明提供的处理机匣,通过轴向错位的缝式结构能够利用通道内上下游的压差将位于动叶片顶部堵塞流动的低能流体抽吸入缝内,同时可以最大限度地将靠近通道下游的低能流体吸入缝内,把这部分流体在动叶片上游喷射出来,改善进入动叶片顶部的流动状况,推迟压气机失速的发生,拓宽压气机的裕度,并且对压气机峰值效率的负面影响较小。(The invention provides an axial seam type processing casing, and belongs to the technical field of gas compressors. Wherein the processor casket includes: the moving blade of the compressor rotor is arranged in the treatment casing, and the edge of the moving blade faces the inner wall of the treatment casing; a plurality of slit structures extending along the axial direction of the processing casing are arranged in the area from the upstream to the downstream of the inner wall of the processing casing corresponding to the edge of the moving blade, and the plurality of slit structures are uniformly distributed along the circumferential direction of the processing casing in a staggered manner. The processing casing provided by the invention can utilize the pressure difference between the upstream and downstream in the channel to suck the low-energy fluid flowing blocked at the top of the moving blade into the gap by virtue of the axially staggered slot structure, and can suck the low-energy fluid close to the downstream of the channel into the gap to the maximum extent, and the fluid is sprayed out from the upstream of the moving blade, so that the flow condition entering the top of the moving blade is improved, the occurrence of the stalling of the gas compressor is delayed, the margin of the gas compressor is widened, and the negative influence on the peak efficiency of the gas compressor is small.)

1. An axial seam type treatment casing is characterized by being applied to a compressor, wherein moving blades of a rotor of the compressor are arranged in the treatment casing, and the edges of the moving blades face the inner wall of the treatment casing;

and a plurality of slit structures extending along the axial direction of the treatment casing are arranged on the inner wall of the treatment casing corresponding to the areas from the upstream to the downstream of the edge of the moving blade, and the plurality of slit structures are uniformly and alternately distributed along the circumferential direction of the treatment casing.

2. A treatment casing according to claim 1, wherein the slot structure has a circumferential cross-sectional shape of an ellipse, a circle or a half-heart; and/or the presence of a gas in the gas,

the seam type structure is an axial seam, a broken line seam or an axial oblique seam.

3. The processing case as set forth in claim 2, wherein the plurality of slot structures are periodically arranged in a staggered manner in a parallelogram or V-shape.

4. A processor cartridge according to claim 3, wherein the number of axial slots per cycle is 4 to 8; and/or the presence of a gas in the gas,

the dislocation distance between the adjacent slot structures in each period is 0-25% of the axial chord length of the blade top of the moving blade.

5. The processor cartridge according to claim 3, wherein the slot structure of the inner wall of the processor cartridge corresponds to a predetermined position upstream of the moving blade tip edge to a tip trailing edge region, the predetermined position upstream of the moving blade tip edge being a predetermined length from the moving blade tip edge, the predetermined length being 0 to 20% of an axial chord length of the moving blade tip.

6. The treatment casing according to claim 3, wherein an axial length of each slot structure is 50% of an axial chord length of the moving blade tip.

7. A processor cartridge according to claim 3, wherein each of said slot structures has an open area ratio of 0.15 to 0.3.

8. A processor cartridge according to claim 3, wherein each of said slot structures is inclined at an angle of 45 ° to 60 ° in a radial direction.

9. The treatment casing according to claim 3, wherein the height of each slot structure is 0.3 to 0.5 times the rotor blade tip axial chord length.

10. The treatment casing according to any one of claims 1 to 9, wherein the compressor used is a radial, mixed or axial compressor of single-stage or multistage construction.

Technical Field

The invention relates to the technical field of gas compressors, in particular to an axial seam type processing casing.

Background

The fan/compressor is one of the core components of the engine, and the advantages and disadvantages of the fan/compressor affect the performance of the engine. In recent years, high-performance engines require a gas compressor to have a high pressure ratio and a high load, so that the internal flow of the gas compressor becomes more complex, secondary flow is intensified, a boundary layer is thickened, tip leakage flow is intensified, a separation area is enlarged, and the stability margin of the gas compressor is reduced. Methods for improving stability margin in compressor design are divided into two major categories, active control and passive control. Compared with active control, the casing processing which is one of passive control technologies is easy to realize, low in modification cost and widely researched. Fig. 1a to 1d are two typical passive control methods of a conventional circumferential slot casing treatment and an axial slot casing treatment, wherein 1a is a schematic axial slot, fig. 1b is a schematic axial slot, fig. 1c is a schematic axial oblique slot, and fig. 1d is a schematic broken line slot. Axial slot casing treatments are widely studied due to their greater stability-extending capability than circumferential slot casing treatments, although the negative impact of the axial slot on efficiency is greater. In recent years, axial slits with semicircular and half-heart-shaped cross-sections have been proposed in succession, greatly reducing losses and the negative impact on efficiency. Researches show that the longer the axial gap is, the stronger the suction effect on low-energy fluid at the downstream of the moving blade is, so that the stability margin of the compressor is improved better, more loss is brought, and the negative influence on the efficiency of the compressor is larger.

Therefore, a processing scheme which can give consideration to the moderate length of the axial seam, realize larger expansion stability and the efficiency of the compressor is needed.

Disclosure of Invention

In view of the above, the present invention provides an axial slot type casing, which solves at least some of the above technical problems.

The embodiment of the invention provides an axial seam type treatment casing, which is applied to a gas compressor, wherein a moving blade of a rotor of the gas compressor is arranged in the treatment casing, and the edge of the moving blade faces to the inner wall of the treatment casing;

and a plurality of slit structures extending along the axial direction of the treatment casing are arranged on the inner wall of the treatment casing corresponding to the areas from the upstream to the downstream of the edge of the moving blade, and the plurality of slit structures are uniformly and alternately distributed along the circumferential direction of the treatment casing.

According to a specific implementation manner of the present disclosure, the circumferential cross-sectional shape of the slot structure is an ellipse, a circle or a half-heart; and/or the presence of a gas in the gas,

the seam type structure is an axial seam, a broken line seam or an axial oblique seam.

According to a specific implementation manner of the present disclosure, the plurality of slit structures are periodically arranged in a staggered manner in a parallelogram or a V shape.

According to a specific implementation manner of the present disclosure, the number of the axial slits per period is 4 to 8; and/or the presence of a gas in the gas,

the dislocation distance between the adjacent slot structures in each period is 0-25% of the axial chord length of the blade top of the moving blade.

According to a specific implementation manner of the present disclosure, the slot structure of the inner wall of the treatment casing corresponds to a preset position upstream of the moving blade tip edge to a blade tip trailing edge region, the preset position upstream of the moving blade tip edge is a preset length away from the moving blade tip edge, and the preset length is 0 to 20% of an axial chord length of the moving blade tip.

According to a specific implementation manner of the present disclosure, the axial length of each slot structure is 50% of the axial chord length of the moving blade tip.

According to a specific implementation of the present disclosure, the ratio of the open area of each of the slot structures is 0.15 to 0.3.

According to a specific implementation manner of the present disclosure, each of the slot structures has a radial inclination angle of 45 ° to 60 °.

According to a specific implementation manner of the present disclosure, the height of each slot structure is 0.3 to 0.5 times of the axial chord length of the moving blade tip.

According to a specific implementation mode of the present disclosure, the applied compressor is a radial flow type, mixed flow type or axial flow type compressor with a single-stage or multi-stage structure.

According to the axial slot type treatment casing provided by the embodiment of the disclosure, the plurality of axial slots are uniformly and periodically distributed on the inner wall of the treatment casing on the periphery of the rotor moving blade along the axial direction and the circumferential direction, so that low-energy blocking fluid distributed along the chord direction generated by a casing wall surface boundary layer and leakage flow is sucked into the slots by utilizing pressure difference generated in the rotor channel along the flow direction, and the blocking of a blade tip area is relieved. In addition, low energy plugging fluid can be delivered upstream and re-injected into the flow channel to improve the effect of leading edge leakage vortices. The low-energy blocking fluid at the downstream of the moving blade is effectively conveyed, the negative effect of the seam length on the efficiency is greatly reduced, and the stalling of the gas compressor is delayed. The scheme disclosed by the invention greatly improves the flow condition of the blade top of the compressor, effectively improves the stability margin of the compressor at different rotating speeds, and has small negative influence on the efficiency.

Drawings

FIGS. 1a to 1d are schematic structural views of a prior art processing casing;

FIG. 2 is a schematic structural diagram of a casing handler according to an embodiment of the present invention;

FIGS. 3 and 4 are schematic views of the slot structure of the casing for a rotor blade according to an embodiment of the present invention for sucking and discharging fluid;

FIGS. 5 and 6 are schematic diagrams of a processing casing according to an embodiment of the present invention, in which slot structures are arranged in a parallelogram and a V-shape in a staggered manner;

fig. 7 is a schematic view of the geometry and parameters of a slot structure in a processing casing according to an embodiment of the present invention.

Summary of reference numerals:

1-a slot-type structure; 2, processing a case; 3, moving blades; 4-a hub; 5-central axis.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to specific embodiments and the accompanying drawings.

Referring to fig. 2, a schematic structural diagram of an axial slot type processing casing according to an embodiment of the present invention is shown. As shown in fig. 2 to 4, the axial slot type casing (hereinafter referred to as a casing 2) is applied to a compressor, a moving blade 3 of the compressor rotor is arranged in the casing 2, and an edge of the moving blade 3 faces an inner wall of the casing 2;

a plurality of slit structures 1 extending in the axial direction of the casing 2 are formed in a region of the inner wall of the casing 2 corresponding to the upstream to downstream of the edge of the rotor blade 3, and the plurality of slit structures 1 are distributed uniformly and in a staggered manner in the circumferential direction of the casing 2.

The processing casing 2 provided in this embodiment is a horn-shaped processing casing having a certain thickness. The rotor blade 3 is provided on a hub 4 of a compressor rotor and is positioned in the casing 2, and the rotor blade 3 is rotatable along a central axis 4 of the casing 2. Considering that the longer the axial seam is, the stronger the suction effect on the blocked low-energy fluid is, the better the stability margin is improved, but the efficiency loss is more serious, and by means of not lengthening the length of the seam and arranging and staggering the seams, the blocked fluid near the tail edge of the blade can be effectively enhanced, so that the margin is better widened, and the characteristic of small negative influence on the efficiency of the compressor is ensured.