阅读说明：本技术 一种超声速吸附式压气机串列静子叶片 (Supersonic adsorption type compressor serial stator blade ) 是由 曹志远 郭伟 宋澄 王楚旋 高玺 张翔 于 2021-07-24 设计创作，主要内容包括：一种超声速吸附式压气机串列静子叶片,前排叶片与后排叶片一一对应组成多个串列静子叶片。所述前排叶片的吸力面与压力面之间开有抽吸腔,该抽吸腔沿叶片叶展方向贯通该以减弱流动分离现象,进行流动控制,通过该串列叶片以保证在提高负荷的条件下,产生较小的流动分离。叶片。在所述前排叶片的吸力面上有抽吸缝；所述抽吸缝为连续抽吸缝或间断抽吸缝或间断错位抽吸缝。本发明提出的超声速吸附式压气机串列静子叶片叶栅通道内气流经过激波后在抽吸以及串列叶片的流动控制技术二者耦合的作用下,流动分离区面积显著减小,流动分离几乎被完全消除。(A tandem stator blade of a supersonic adsorption type compressor is characterized in that a plurality of tandem stator blades are formed by corresponding front row blades and rear row blades one by one. And a suction cavity is arranged between the suction surface and the pressure surface of the front row of blades, the suction cavity penetrates through the front row of blades in the blade expanding direction to weaken the flow separation phenomenon for flow control, and the tandem blades ensure that small flow separation is generated under the condition of improving the load. A blade. A suction surface of the front row of blades is provided with a suction slit; the suction seam is a continuous suction seam or an intermittent dislocation suction seam. The area of the flow separation area is obviously reduced and the flow separation is almost completely eliminated under the coupling effect of suction and the flow control technology of the tandem blades after the gas flow in the blade grid channel of the tandem stator blade of the supersonic adsorption type gas compressor provided by the invention passes through the shock wave.)

1. A supersonic adsorption type compressor tandem stator blade comprises a plurality of front row blades and a plurality of rear row blades; a plurality of tandem stator blades are formed by corresponding the front row blades and the rear row blades one by one; the suction cavity is arranged between the suction surface and the pressure surface of the front row of blades and penetrates through the blades along the blade unfolding direction; a suction surface of the front row of blades is provided with a suction slit; the suction seam is a continuous suction seam or an intermittent staggered suction seam; the suction slits are distributed along the span direction of the front row of blades and are communicated with the suction cavity; the width of each suction slit is 1.8 mm;

the front row of blades are in cascade connection with the rear row of blades through a suction seam formed on the suction surface and a suction cavity inside the front row of blades, and are fixed on the hub, and meanwhile, the suction seam is formed at the end wall of the suction surface of the hub along the suction surface, so that the tandem stator blade of the supersonic adsorption type gas compressor is formed; a plurality of front row blade end wall suction slits and rear row blade end wall suction slits are added on the hub;

the blade root of each series of stator blades is arranged on the outer circumferential surface of a hub of the compressor, the blade tip of each series of stator blades is arranged on the inner circumferential surface of a rectifying casing of the compressor, and the front edge of each series of stator blades faces the incoming flow.

2. The tandem stator vane of the supersonic adsorption type compressor as claimed in claim 1, wherein the vertex of the front edge of the suction cavity is 22.4% of chord length from the front edge of the vane in the chord length direction, and the vertex of the rear front edge of the suction cavity is 73.9% of chord length from the front edge of the vane in the chord length direction; the profile of the upper surface of the suction cavity is the same as that of the suction surface of the blade; the profile of the lower surface of the suction cavity is the same as the profile of the pressure surface; both ends of the suction cavity are circular arcs with the radius of 0.4 mm; the wall thickness of the suction chamber is 0.5 mm.

3. The tandem stator vane of a supersonic adsorption compressor as defined in claim 1, wherein:

when a continuous suction slot is adopted, the suction slot is a continuous rectangular groove, and the center line of the width direction of the suction slot is positioned at the chord length of 43 percent of the front row of blades;

when an intermittent suction slot is adopted, the suction slot consists of a plurality of single suction slots arranged along the blade expanding direction, and the center line of the width direction of the suction slot is positioned at the 43 percent chord length of the front row of blades; the length of each single suction slot is 18mm, and the distance between the adjacent edges of the two suction slots is 2 mm; the single suction slots are arranged from the blade tip;

when the intermittent staggered suction slot is adopted, the suction slot consists of a plurality of single suction slots which are arranged along the blade unfolding direction, and the single suction slots are arranged in two rows on the suction surface of the front row of blades in a staggered manner, so that the center line of one row of suction slots in the width direction is positioned at the position of 43% chord length of the front row of blades, and the center line of the other row of suction slots in the width direction is positioned at the position of 45% chord length of the front row of blades; the length of each of the individual suction slits is 18 mm.

4. The tandem stator vane of a supersonic adsorption compressor as defined in claim 1, wherein: in the same tandem blade:

the intersection point of the camber line of the front row of blades and the front edge of the front row of blades is the front edge of the tandem blade, the intersection point of the camber line of the rear row of blades and the rear edge of the rear row of blades is the rear edge of the tandem blade, and a connecting line between the front edge and the rear edge is made to obtain the total chord length of the tandem blade; the total chord length of the tandem blade is 65 mm;

the axial distance between the rear edge of the front row of blades and the front edge of the rear row of blades is-3 mm, and the circumferential offset distance between the rear edge of the front row of blades and the front edge of the rear row of blades is 4 mm;

the included angle between the tangent line of the camber line of the front row of blades at the front edge point of the front row of blades and the tangent line of the camber line of the rear row of blades at the rear edge point of the rear row of blades is a total bend angle, and the total bend angle is 13 degrees.

5. The tandem stator vane of a supersonic adsorption compressor as defined in claim 1, wherein: when the stator blade is installed, the front edge of the front row of blades in each tandem stator blade is positioned at 5% of the axial length of the hub; the total mounting angle of each tandem blade is 37 degrees.

6. The tandem stator vane of a supersonic adsorption compressor as defined in claim 1, wherein: the height of the front row of blades is 100mm, the chord length of the blades is 45mm, the inlet geometric angle is 14 degrees, and the outlet geometric angle is-14 degrees; when the blades are installed on the hub, the spacing between adjacent front-row blades is 30.55mm, the installation angle is 47 degrees, and the inlet airflow angle is 61 degrees.

7. The tandem stator vane of a supersonic adsorption compressor as defined in claim 1, wherein: the convex cambered surface of the front row of blades is a suction surface, and the concave cambered surface is a pressure surface; the maximum thickness position point of the front row of blades is positioned at the position of 42 percent of the chord length of the blades; the radius of a suction surface between the maximum thickness position point and the rear edge of the front row of blades is a circular arc surface of 150 mm; the suction surface between the maximum thickness position point and the front edge of the front row of blades is a plane; the arc surface and the plane are smoothly intersected at the position of the maximum thickness; the pressure surface of the front row of blades adopts an arc surface with the radius of 170 mm.

8. The tandem stator vane of a supersonic adsorption compressor as defined in claim 1, wherein: the chord length of the rear row of blades is 33mm, and the blade height is 100 mm; the maximum thickness is positioned at 50% of the chord length of the rear row of blades and is 14 mm; the convex cambered surface of the rear row of blades is a suction surface, and the concave cambered surface is a pressure surface; the radius of the suction surface is 87.8mm and the radius of the pressure surface is 138 mm.

9. The tandem stator vane of a supersonic adsorption compressor as defined in claim 1, wherein: the front-row blade end wall suction slit is positioned on one side of the suction surface of the front-row blade and extends along the chord direction; the width of the front row of blade end wall suction slits is 1.8 mm; the distance from the central line of the front row of blade end wall in the width direction to the suction surface of the blade is 3 mm; the shape of the front-row blade end wall suction slit is the same as the profile of the front-row blade suction surface; the front row blade suction slit is divided into a front section and a rear section; the front section of the suction slot is a continuous suction slot, the starting point is positioned at the chord length of 8-13% of the front edge of the front row of blades, and the end point is positioned at the chord length of 43% of the front edge of the front row of blades; the rear section suction slot consists of a plurality of discontinuous small suction slots, and the starting point of the rear section suction slot is positioned at the chord length position 45% away from the front row of blades, and the terminal point of the rear section suction slot is positioned at the chord length position 100% away from the front row of blades; the spacing distance between every two adjacent small suction slits in the rear-section intermittent suction slits is 2% of the chord length of the front-row blades; the length of each small suction slit is 3% of the chord length of the front row of blades.

10. The tandem stator vane of a supersonic adsorption compressor as defined in claim 1, wherein:

the rear row blade end wall suction slit is positioned on one side of the suction surface of the rear row blade and extends along the chord direction, and the width of the rear row blade end wall suction slit is 1.8 mm; the shape of the suction slit of the end wall of the back row of blades is the same as the profile of the suction surface of the back row of blades; the rear-row blade end wall suction slit is divided into a first suction slit and a second suction slit;

the first suction slit is divided into a front section and a rear section; the front section of the first suction slot is a continuous suction slot, the starting point is located at the position 3% chord length away from the front edge of the rear row of blades, and the end point is located at the position 78% chord length away from the front edge of the rear row of blades; the rear section of the first suction slot consists of a plurality of discontinuous small suction slots, and the starting point of the rear section is positioned at the chord length 80% away from the front edge of the rear row of blades, and the end point of the rear section is positioned at the chord length 100% away from the front edge of the rear row of blades; the distance between the central line of the first suction slit in the width direction and the suction surface of the blade is 6 mm;

the second suction slot is also divided into a front section and a rear section; the front section of the first suction slot is a continuous suction slot, the starting point is located 17% chord length from the front edge of the rear row of blades, and the end point is located 78% chord length from the front edge of the rear row of blades; the rear section of the second suction slot consists of a plurality of discontinuous small suction slots, and the starting point of the rear section is positioned at the chord length 80% away from the front edge of the rear row of blades, and the end point of the rear section is positioned at the chord length 100% away from the front edge of the rear row of blades; the distance from the central line of the second suction slit in the width direction to the suction surface of the blade is 3 mm;

the spacing distance between adjacent small suction slits in the small suction slits at the rear section of the first suction slit and the small suction slits at the rear section of the second suction slit is 2 percent of the chord length of the rear row of blades; the length of each small suction slit is 3% of the chord length of the rear row of blades.

Technical Field

The invention relates to the field of an aircraft engine compressor, in particular to a supersonic speed adsorption type tandem stator blade.

Background

With the rapid development of modern advanced aviation power devices, the demand of engines with large thrust-weight ratios is increasingly urgent. The high thrust-weight ratio engine requires the compressor to work under the conditions of high pressure ratio, high efficiency and wide margin, so that the load of the compressor is continuously improved, and the high pressure ratio enables a strong backpressure gradient to exist in the compressor, so that the flow separation of the suction surface of the blade under the action of controlling the strong backpressure gradient becomes an important factor to be considered in the pneumatic research of the compressor. Therefore, under the condition that the rotating speed of the compressor is limited, the development of a novel flow control method becomes an important research content of the pneumatic design of the compressor of the aircraft engine.

Tandem vane cascades as a means of passive Flow control technology, U.K. Saha, and B.Roy in "Experimental investments on Tandem Compressor case Performance at Low Speeds" ("Experimental Thermal and Fluid Science 1997 edition, 3, 14, volume), and E.Feind in" Exact clinical of the Flow of a stabilized Tandem case with Moving Second Blade Row "(archives of Applied Mechanics 2001, 9, 71, volume), indicate that the Flow separation phenomenon can be reduced on an aeroengine in the form of a Tandem vane Cascade, i.e. in the form of a front Row of vanes and a rear Row of vanes on the same stage of stator vanes.

Boundary layer pumping technology, one of the active flow control technologies, was first proposed by J.L. Kerreblank et al, MIT 1997, in Proceedings of the ASME 1997International Gas Turbine and Aeroengine consistency and inhibition 1997, volume 1, Aspirated Compressors, and gradually gained attention from researchers. The predominantly completed single stage adsorption transonic Compressor described by MIT Ali Merchant in Design and Analysis of Axial assisted Compressor Stages (the Thesis Massachusetts Institute of Technology 1999) has proven the success of boundary layer pumping Technology.

The research on the boundary layer suction technology in China mainly focuses on the aspect of numerical simulation of a cascade, the research on the aspect of numerical simulation of the cascade is introduced by Chengfu et al in engineering thermophysics journal 2 in 2005 in the influence of boundary layer suction on the consistency characteristic of the cascade of a gas compressor and by Gezhenwei et al in aeronautical dynamics journal 8 in 2007 in 8 in the numerical simulation of a flow field of the cascade of an adsorption transonic speed gas compressor, the research shows that the adsorption type cascade has small influence on the quality of a single stage of the gas compressor, the thrust-weight ratio of the aeroengine can be effectively improved, and meanwhile, the problem of the strength of blades caused by the extraction of movable blades is required to be pointed out, and the problem does not exist when the air is extracted from stationary blades.

The Lanxiang et al respectively carry out experimental research on a span/supersonic velocity adsorption type compressor blade cascade in a span and supersonic velocity adsorption type compressor plane blade cascade test (the 5 th year 2010 of the aviation dynamics journal), and explore the influence of the position of a suction slit, suction flow, shock wave intensity and the like on a blade cascade flow field.

A single-stage compressor with a pressure ratio exceeding 4.5 is designed in a doctor's scientific paper of Cao Shi far, namely research on flow control and performance influence of boundary layer suction on an axial flow compressor, and diffusion and flow guiding are difficult to realize through a single row of blades under the condition of supersonic velocity incoming flow.

In the invention and creation of application No. 202011316109.8, a supersonic adsorption type compressor blade based on multiple holes is disclosed, which reduces the flow separation phenomenon by performing multiple hole suction on the supersonic compressor blade.

The invention with the publication number of CN120214029 discloses a combined suction type cascade experimental device, which is characterized in that grooves are respectively formed in the end wall of a cascade and the suction surface of a blade, and low-energy fluid is respectively pumped out from the end wall and the suction surface, so that the purpose of respectively controlling the suction flow of the end wall and the suction surface of the blade is achieved.

The technical solutions disclosed in the above documents/inventions are all based on the research results of blades under various flow control technologies under supersonic incoming flow conditions, and although the flow condition is improved, the flow separation phenomenon cannot be controlled well, and the control by suction will cause the generation of shock wave/wall interference phenomenon, so that the shock wave is enhanced, and the shock wave position is changed, which will cause more serious flow separation phenomenon.

Disclosure of Invention

In order to overcome the defects that the adoption of an adsorption type blade can generate shock wave/wall interference effect under the condition of supersonic incoming flow, induce shock wave enhancement and position change and generate larger flow separation phenomenon in the prior art, the invention provides a supersonic adsorption type compressor tandem stator blade.

The invention comprises a plurality of front-row blades and a plurality of rear-row blades; and a plurality of tandem stator blades are formed by corresponding the front row blades and the rear row blades one by one. And a suction cavity is arranged between the suction surface and the pressure surface of the front row of blades and penetrates through the blades along the blade unfolding direction. A suction surface of the front row of blades is provided with a suction slit; the suction seam is a continuous suction seam or an intermittent dislocation suction seam. The suction slots are distributed along the span direction of the front row of blades and are communicated with the suction cavity. The width of each suction slit is 1.8 mm.

The front row of blades are in cascade connection with the rear row of blades through a suction seam formed on the suction surface and a suction cavity inside the front row of blades, and are fixed on the hub, and meanwhile, the suction seam is formed on the end wall of the suction surface of the hub along the suction surface, so that the tandem stator blade of the supersonic speed adsorption type gas compressor is formed. A plurality of front row blade end wall suction slots and rear row blade end wall suction slots are added to the hub.

The blade root of each series of stator blades is arranged on the outer circumferential surface of a hub of the compressor, the blade tip of each series of stator blades is arranged on the inner circumferential surface of a rectifying casing of the compressor, and the front edge of each series of stator blades faces the incoming flow.

The vertex of one end of the front edge of the suction cavity is 22.4 percent of chord length from the front edge of the blade in the chord length direction, and the vertex of one end of the rear front edge of the suction cavity is 73.9 percent of chord length from the front edge of the blade in the chord length direction. The profile of the upper surface of the suction cavity is the same as that of the suction surface of the blade; the profile of the lower surface of the suction chamber is the same as the profile of the pressure surface. Both ends of the suction cavity are circular arcs with the radius of 0.4 mm. The wall thickness of the suction chamber is 0.5 mm.

When a continuous suction slot is used, the slot is a continuous rectangular groove with the widthwise centerline of the slot at 43% of the chord length of the leading row of vanes.

When an intermittent suction slot is used, the slot is composed of a plurality of individual suction slots arranged in the spanwise direction, and the center line of the width direction of the slot is located at the 43% chord length of the front row of blades. The length of each single suction slot is 18mm, and the distance between the adjacent edges between two suction slots is 2 mm. The single suction slot is arranged from the blade tip.

When the intermittent staggered suction slots are adopted, the suction slots are composed of a plurality of single suction slots which are arranged along the blade extending direction, and the single suction slots are arranged in two rows on the suction surface of the front row of blades in a staggered mode, so that the center line of the width direction of one row of suction slots is located at the 43 percent chord length of the front row of blades, and the center line of the width direction of the other row of suction slots is located at the 45 percent chord length of the front row of blades. The length of each of the individual suction slits is 18 mm.

In the same tandem blade:

the intersection point of the camber line of the front row of blades and the front edge of the front row of blades is the front edge of the tandem blade, the intersection point of the camber line of the rear row of blades and the rear edge of the rear row of blades is the rear edge of the tandem blade, and a connecting line between the front edge and the rear edge is made to obtain the total chord length of the tandem blade; the total chord length of the tandem blade is 65 mm.

The axial distance between the rear edge of the front row of blades and the front edge of the rear row of blades is-3 mm, and the circumferential offset distance between the rear edge of the front row of blades and the front edge of the rear row of blades is 4 mm.

The included angle between the tangent line of the camber line of the front row of blades at the front edge point of the front row of blades and the tangent line of the camber line of the rear row of blades at the rear edge point of the rear row of blades is a total bend angle, and the total bend angle is 13 degrees.

When the stator blade is installed, the front edge of the front row of blades in each tandem stator blade is positioned at 5% of the axial length of the hub. The total mounting angle of each tandem blade is 37 degrees.

The height of the front row of blades is 100mm, the chord length of the blades is 45mm, the inlet geometric angle is 14 degrees, and the outlet geometric angle is-14 degrees. When the blades are installed on the hub, the spacing between adjacent front-row blades is 30.55mm, the installation angle is 47 degrees, and the inlet airflow angle is 61 degrees.

The convex cambered surface of the front row of blades is a suction surface, and the concave cambered surface is a pressure surface. The point of maximum thickness of the leading row of blades is at 42% of the blade chord length. The radius of a suction surface between the maximum thickness position point and the rear edge of the front row of blades is a circular arc surface of 150 mm; the suction surface between the maximum thickness position point and the front edge of the front row of blades is a plane; the arc surface and the plane are smoothly intersected at the maximum thickness position point. The pressure surface of the front row of blades adopts an arc surface with the radius of 170 mm.

The chord length of the rear row of blades is 33mm, and the blade height is 100 mm; the maximum thickness is positioned at 50% of the chord length of the rear row of blades and is 14 mm; the convex cambered surface of the rear row of blades is a suction surface, and the concave cambered surface is a pressure surface; the radius of the suction surface is 87.8mm and the radius of the pressure surface is 138 mm.

The front-row blade end wall suction slit is positioned on one side of the suction surface of the front-row blade and extends along the chord direction; the width of the front row of blade end wall suction slits is 1.8 mm; the distance from the central line of the front row of blade end wall in the width direction to the suction surface of the blade is 3 mm; the shape of the front-row blade end wall suction slit is the same as the profile of the front-row blade suction surface;

the front row blade suction slit is divided into a front section and a rear section; the front section of the suction slot is a continuous suction slot, the starting point is positioned at the chord length of 8-13% of the front edge of the front row of blades, and the end point is positioned at the chord length of 43% of the front edge of the front row of blades; the rear section suction slot consists of a plurality of discontinuous small suction slots, and the starting point of the rear section suction slot is positioned at the chord length position 45% away from the front row of blades, and the terminal point of the rear section suction slot is positioned at the chord length position 100% away from the front row of blades; the spacing distance between every two adjacent small suction slits in the rear-section intermittent suction slits is 2% of the chord length of the front-row blades; the length of each small suction slit is 3% of the chord length of the front row of blades.

The rear row blade end wall suction slit is positioned on one side of the suction surface of the rear row blade and extends along the chord direction, and the width of the rear row blade end wall suction slit is 1.8 mm; the shape of the suction slit of the end wall of the back row of blades is the same as the profile of the suction surface of the back row of blades; the rear-row blade end wall suction slit is divided into a first suction slit and a second suction slit;

the first suction slit is divided into a front section and a rear section; the front section of the first suction slot is a continuous suction slot, the starting point is located at the position 3% chord length away from the front edge of the rear row of blades, and the end point is located at the position 78% chord length away from the front edge of the rear row of blades; the rear section of the first suction slot consists of a plurality of discontinuous small suction slots, and the starting point of the rear section is positioned at the chord length 80% away from the front edge of the rear row of blades, and the end point of the rear section is positioned at the chord length 100% away from the front edge of the rear row of blades; the distance between the central line of the first suction slit in the width direction and the suction surface of the blade is 6 mm;

the second suction slot is also divided into a front section and a rear section; the front section of the first suction slot is a continuous suction slot, the starting point is located 17% chord length from the front edge of the rear row of blades, and the end point is located 78% chord length from the front edge of the rear row of blades; the rear section of the second suction slot consists of a plurality of discontinuous small suction slots, and the starting point of the rear section is positioned at the chord length 80% away from the front edge of the rear row of blades, and the end point of the rear section is positioned at the chord length 100% away from the front edge of the rear row of blades; the distance from the central line of the second suction slit in the width direction to the suction surface of the blade is 3 mm;

the spacing distance between adjacent small suction slits in the small suction slits at the rear section of the first suction slit and the small suction slits at the rear section of the second suction slit is 2 percent of the chord length of the rear row of blades; the length of each small suction slit is 3% of the chord length of the rear row of blades.

The tandem stator blades of the compressor are divided into stator blades in a front row and stator blades in a rear row, which are referred to as front row blades and rear row blades for short. In order to reduce the flow separation phenomena as far as possible, a flow control is carried out, by means of which a small flow separation is ensured under increased load. The front row of blades bears most of the load, and the rear row of blades is responsible for turning the airflow.

The front row of blades bear most of load, and the blade profile curvature and the derivative thereof directly influence the performance of the blades, so the specific theoretical analysis of the blade profile design of the blades comprises the steps of determining the curvature distribution change of a molded line from a front edge to a rear edge on a suction surface side through the rule that a boundary layer grows along the suction surface side, deducing coordinates of each point on the suction surface side from the curvature distribution change, then determining the area distribution of a cross section, calculating the curvature distribution of the molded line on a pressure surface side through comprehensive constraint conditions, and also deducing the coordinates of each point on the pressure surface side. In order to close the molded line suction surface and the pressure surface, the pressure surface side front edge and the suction surface side front edge are smoothly connected, and the pressure surface side rear edge and the suction surface side rear edge are smoothly connected, so that a complete front-row blade two-dimensional section blade profile is obtained.

Compared with the prior art, the invention has the following beneficial effects:

the invention adopts a full three-dimensional pneumatic optimization design method to design the blades. In the design, suction of the boundary layer of the suction surface is adopted to control flow separation of the blades, the shock wave/wall interference effect is weakened, the structural strength of the blades is increased, and the shock wave front Mach number is reduced by utilizing the pre-compressed blade profile. After the preliminary design of the tandem stator blades of the supersonic adsorption type compressor is completed, the tandem stator blades of the supersonic adsorption type compressor are distributed into a blade grid according to the design working condition, and the three-dimensional numerical simulation is carried out on the blade grid.

The suction slit is adopted to control the flow separation under the condition of supersonic incoming flow, so that the shock wave/wall interference phenomenon exists, the suction can further enhance the shock wave, the shock wave position is changed, and the change of the shock wave position induces stronger flow separation.

According to the invention, through the intermittent suction slits arranged on the end wall of the front row of blades, the shock waves are just hit on the intermittent suction slits at the shock wave impact point 7, so that expansion waves are generated, the expansion waves are intersected with the shock waves and further weakened or offset with each other, so that the shock wave/wall surface interference phenomenon caused by suction is weakened or eliminated, the effect of suction under the condition of supersonic velocity incoming flow is completely reflected, and the flow separation phenomenon is controlled. The pumped low energy fluid is collected by converging low energy fluid at 8.

Because the invention adopts the tandem blades, the front-row blades can have low-energy fluid in the wake and the end wall area, the rear-row blade end wall suction seams adopt a double-seam structure, the first suction seam sucks the low-energy fluid in the wake and the end wall area of the front-row blades, the second suction seam sucks the low-energy fluid in the rear-row blades, and meanwhile, in order to control the suction flow, intermittent suction seams are adopted at 78% of the length of the suction seams, so that the flow loss is avoided.

Meanwhile, the adsorption-type tandem stator blade can reduce the weight of the stator blade and eliminate the flow separation phenomenon.

In the cascade channels of the tandem blades which are not sucked, the airflow passes through the bow shock wave 6 to generate flow separation, and the area of the flow separation area is large, so that serious loss is caused.

In the blade grid channel of the tandem stator blade of the supersonic adsorption type gas compressor, the area of the flow separation area is obviously reduced under the coupling effect of suction and the flow control technology of the tandem blade after the gas flow is subjected to shock, and the flow separation is almost completely eliminated.

Drawings

FIG. 1 is a front view of a tandem vane leading row of a supersonic absorption compressor having various forms of suction slots; wherein: fig. 1a shows a continuous rectangular suction slot, fig. 1b shows an interrupted rectangular suction slot, and fig. 1c shows a staggered rectangular suction slot.

FIG. 2 is a top view of tandem vanes of a supersonic absorption compressor having suction slots;

FIG. 3 is a schematic view of a shock wave structure in a cascade channel of tandem blades of a supersonic adsorption type compressor;

FIG. 4 is a schematic view of the front row blade and the back row blade end wall suction slots of the tandem blades of the supersonic adsorption type compressor;

FIG. 5 is a three-dimensional view of a set of tandem vanes of a supersonic absorption compressor having suction slots according to the present invention;

fig. 6 is a three-dimensional view of a supersonic suction compressor tandem blade with suction slots of the present invention.

FIG. 7 is a Mach number cloud for tandem blades without suction under design conditions;

FIG. 8 is a Mach number cloud for tandem blades according to the present invention at design conditions.

In the figure: 1. a front row of blades; 2. a rear row of blades; 3. a suction slot; 4. a suction lumen; 5. a hub; 6. bow shock waves; 7. shock wave impact points; 8. a low energy fluid convergence; 9. a rectifier case; 10. front row vane end wall suction slots; 11. rear row vane end wall suction slots; 12. a first suction slit; 13. a second suction slit.

Detailed Description

The embodiment is a tandem stator blade of a supersonic adsorption type compressor, which comprises a plurality of front-row blades 1 and a plurality of rear-row blades 2. And a plurality of tandem stator blades are formed by corresponding the front row blades and the rear row blades one by one. The blade root of each series of stator blades is arranged on the outer circumferential surface of a hub 5 of the compressor, the blade tip of each series of stator blades is arranged on the inner circumferential surface of a rectifying casing 9 of the compressor, and the front edge of each series of stator blades faces the incoming flow.

The front row of blades are in cascade connection with the rear row of blades through a suction seam formed on the suction surface and a suction cavity inside the front row of blades, and are fixed on the hub, and meanwhile, the suction seam is formed on the end wall of the suction surface of the hub along the suction surface, so that the tandem stator blade of the supersonic speed adsorption type gas compressor is formed.

In the same tandem blade:

the intersection point of the camber line of the front row of blades and the front edge of the front row of blades is the front edge of the tandem blade, the intersection point of the camber line of the rear row of blades and the rear edge of the rear row of blades is the rear edge of the tandem blade, and a connecting line between the front edge and the rear edge is made to obtain the total chord length of the tandem blade; the total chord length of the tandem blade is 65 mm.

The axial distance between the rear edge of the front row of blades and the front edge of the rear row of blades is-3 mm, and the circumferential offset distance between the rear edge of the front row of blades and the front edge of the rear row of blades is 4 mm.

The included angle between the tangent line of the camber line of the front row of blades at the front edge point of the front row of blades and the tangent line of the camber line of the rear row of blades at the rear edge point of the rear row of blades is a total bend angle, and the total bend angle is 13 degrees.

When the stator blade is installed, the front edge of the front row of blades in each tandem stator blade is positioned at 5% of the axial length of the hub. The total mounting angle of each tandem blade is 37 degrees.

The front row of blades have the blade height of 100mm, the chord length of 45mm, the inlet geometric angle of 14 degrees and the outlet geometric angle of-14 degrees. When the blades are installed on the hub, the spacing between adjacent front-row blades is 30.55mm, the installation angle is 47 degrees, and the inlet airflow angle is 61 degrees.

The convex cambered surface of the front row of blades is a suction surface, and the concave cambered surface is a pressure surface. The point of maximum thickness of the leading row of blades is at 42% of the blade chord length. The radius of a suction surface between the maximum thickness position point and the rear edge of the front row of blades is a circular arc surface of 150 mm; the suction surface between the maximum thickness position point and the front edge of the front row of blades is a plane; the arc surface and the plane are smoothly intersected at the maximum thickness position point. The pressure surface of the front row of blades adopts an arc surface with the radius of 170 mm.

Between the suction side and the pressure side of the front row of blades, a suction chamber 4 is provided, which extends through the blades in the spanwise direction of the blades. The two ends of the suction cavity are arc-shaped, and the radius of the arc is 0.4 mm. The vertex of one end of the front edge of the suction cavity is 22.4 percent of chord length from the front edge of the blade in the chord length direction, and the vertex of one end of the rear front edge of the suction cavity is 73.9 percent of chord length from the front edge of the blade in the chord length direction. The profile of the upper surface of the suction cavity is the same as that of the suction surface of the blade; the profile of the lower surface of the suction chamber is the same as the profile of the pressure surface. The wall thickness of the suction chamber is 0.5 mm.

A suction slit 3 is arranged on the suction surface of the front row of blades; the suction seam is a continuous suction seam or an intermittent dislocation suction seam. The blades are distributed along the spanwise direction of the front row of blades. The width of each suction slit is 1.8mm and is communicated with the suction cavity.

When a continuous suction slot is used, the slot is a continuous rectangular groove with the widthwise centerline of the slot at 43% of the chord length of the leading row of vanes.

When an intermittent suction slot is used, the slot is composed of a plurality of individual suction slots arranged in the spanwise direction, and the center line of the width direction of the slot is located at the 43% chord length of the front row of blades. The length of each single suction slot is 18mm, and the distance between the adjacent edges between two suction slots is 2 mm. The single suction slot is arranged from the blade tip. In this example, the blade height is 100mm, and there are 5 single suction slots in total along the spanwise direction of the front row of blades.

When the intermittent staggered suction slots are adopted, the suction slots are composed of a plurality of single suction slots which are arranged along the blade extending direction, and the single suction slots are arranged in two rows on the suction surface of the front row of blades in a staggered mode, so that the center line of the width direction of one row of suction slots is located at the 43 percent chord length of the front row of blades, and the center line of the width direction of the other row of suction slots is located at the 45 percent chord length of the front row of blades. The length of each of the individual suction slits is 18 mm. In this embodiment, the distance between adjacent edges between two suction slots in the same row is 22 mm.

The chord length of the back row of blades is 33mm, and the blade height is 100 mm. The maximum thickness is 50% of the chord length of the back row of blades and the maximum thickness is 14 mm. The convex cambered surface of the back row of blades is a suction surface, and the concave cambered surface is a pressure surface. The radius of the suction surface is 87.8mm and the radius of the pressure surface is 138 mm.

The hub 5 is an improvement over the prior art. The improvement is that a plurality of leading row blade endwall suction slots 10 and trailing row blade endwall suction slots 11 are added to the hub.

The front-row blade end wall suction slit is positioned on one side of the suction surface of the front-row blade and extends along the chord direction; the front-row blade suction seam is divided into a front section and a rear section, the front-section suction seam is a continuous suction seam, the starting point is positioned at the position 8% -13% of the chord length from the front edge of the front-row blade, and the end point is positioned at the position 43% of the chord length from the front edge of the front-row blade; the rear section suction slot consists of a plurality of discontinuous small suction slots, and the starting point of the rear section suction slot is positioned at the chord length position 45% away from the front row of blades, and the terminal point of the rear section suction slot is positioned at the chord length position 100% away from the front row of blades; the spacing distance between every two adjacent small suction slits in the rear-section intermittent suction slits is 2% of the chord length of the front-row blades; the length of each small suction slit is 3% of the chord length of the front row of blades.

The width of the front row of blade end wall suction slits is 1.8 mm; the distance from the central line of the front row of blade end wall in the width direction to the suction surface of the blade is 3 mm. The shape of the front-row blade end wall suction slit is the same as the profile of the front-row blade suction surface. In this embodiment, the position of the front-row vane end wall suction slit is 9% to 100% of the chord length of the front-row vane.

The rear row blade end wall suction slit is positioned on one side of the suction surface of the rear row blade and extends along the chord direction, and the width of the rear row blade end wall suction slit is 1.8 mm; the shape of the suction slit of the end wall of the back row of blades is the same as the profile of the suction surface of the back row of blades. The trailing blade-end wall suction slit 11 is divided into a first suction slit 12 and a second suction slit 13. The first suction slot is divided into two sections, the suction slot positioned at the front section is a continuous suction slot, the starting point is positioned at the position 3% chord length away from the front edge of the rear row of blades, and the ending point is positioned at the position 78% chord length away from the front edge of the rear row of blades. The rear section suction slot of the first suction slot consists of a plurality of discontinuous small suction slots, and the starting point of the rear section suction slot is positioned at the chord length 80% away from the front edge of the rear row of blades, and the end point of the rear section suction slot is positioned at the chord length 100% away from the front edge of the rear row of blades; the spacing distance between every two adjacent small suction slits in the rear-section intermittent suction slits is 2% of the chord length of the rear-row blades; the length of each small suction slit is 3% of the chord length of the rear row of blades. The distance from the central line of the first suction slit in the width direction to the suction surface of the blade is 6 mm.

The second suction slot is also divided into two sections, the suction slot positioned at the front section is a continuous suction slot, the starting point is positioned 17 percent of the chord length from the front edge of the rear row of blades, and the ending point is positioned 78 percent of the chord length from the front edge of the rear row of blades.

The rear section suction slot of the second suction slot consists of a plurality of discontinuous small suction slots, and the starting point of the rear section suction slot is positioned at the chord length 80% away from the front edge of the rear row of blades, and the end point of the rear section suction slot is positioned at the chord length 100% away from the front edge of the rear row of blades; the spacing distance between every two adjacent small suction slits in the rear-section intermittent suction slits is 2% of the chord length of the rear-row blades; the length of each small suction slit is 3% of the chord length of the rear row of blades. The distance from the center line of the second suction slit in the width direction to the suction surface of the vane was 3 mm.