WO2023035576A1

WO2023035576A1 - Plane cascade flow field quality improvement system combining suction and flow guide tail plate

Info

Publication number: WO2023035576A1
Application number: PCT/CN2022/081076
Authority: WO
Inventors: 孙鹏; 傅文广; 杨昭; 李晓东; 杨坤; 刘帅
Original assignee: 中国民航大学
Priority date: 2021-09-10
Filing date: 2022-03-16
Publication date: 2023-03-16
Also published as: CN113758670B; CN113758670A

Abstract

A plane cascade flow field quality improvement system combining suction and a flow guide tail plate. The plane cascade flow field quality improvement system comprises a fixed base (1) and a cascade test bench (2) provided on the fixed base (1). An air supply tube (3) is provided at one end of the cascade test bench (2), an air discharging port (4) is provided at the other end of the cascade test bench, and a cascade test member is provided in the middle of the cascade test bench (2); the left and right sides of the cascade test bench (2) are correspondingly provided with a left rotating disc (5) and a right rotating disc (9), the left rotating disc (5) and the right rotating disc (9) are rotatably mounted on the cascade test bench (2), and an air guide gap communicated with the air supply tube (3) exists between the left rotating disc (5) and the right rotating disc (9); one side of the cascade test member is provided on the left rotating disc (5), and the other side of the cascade test member is provided on the right rotating disc (9). In the system, the quality of the cascade flow field is improved in a manner of combining a suction mechanism and a flow guide mechanism, a good improvement effect is achieved, operation and adjustment are simple and convenient, and accurate adjustment and improvement of the quality of the cascade flow field can be achieved.

Description

A system for improving the flow field quality of a plane cascade combined with suction and deflector tail

technical field

The invention belongs to the test field of plane cascades, in particular to a system for improving the flow field quality of plane cascades combined with suction and deflector tail plates.

Background technique

Under the standard flow conditions, the wind tunnel test of the plane cascade can directly obtain the aerodynamic performance parameters of different blade shapes, and establish the relationship between the primitive velocity triangle and the geometric parameters of the cascade efficiently, quickly and intuitively. The hole has become an important basic experimental research equipment for axial flow turbomachinery (compressor, turbine). The flow field quality of the planar cascade can determine whether the tester meets the test requirements. The flow field quality refers to the ability of the planar cascade composed of finite blades to simulate the ideal periodicity of infinitely many and infinitely high blades. There are two main reasons affecting the quality of the flow field of the plane cascade tester: one is that the fluid will produce a boundary layer when it contacts the side plate of the tester, and the boundary layer will continue to develop along the airflow direction, thus directly affecting the flow field in front of the cascade. Uniformity of the flow field; on the other hand, the inherent structure of the cascade wind tunnel test section will cause blockage of the cascade channel near the upper side wall. If the number of blades is not large enough, this blockage will spread to the middle of the cascade channel, thereby affecting the accuracy of the test data.

At present, in order to obtain accurate cascade performance parameters, the inlet low-energy fluid is usually sucked by end wall suction. After testing, there are still following defects:

(1) There is a certain distance between the position of the suction slot on the front wall of the grid and the front edge of the cascade, which can improve the flow field quality of the plane cascade under the test conditions of small angle of attack and low Mach number. However, the end wall suction driven by the pressure difference between the suction chamber and the test section has limited ability to adjust the flow rate of each channel of the planar cascade. With the increase of the test angle of attack and Mach number, the range of pressure difference used for suction also increases, and the required suction flow rate increases, which makes it more difficult and costly to control the quality of the flow field.

(2) Most of the existing suction methods are adjusted by controlling the vacuum flow of the vacuum pump. Since the method is driven by the pressure difference between the flow field in the test section and the flow field in the vacuum pump, it is less difficult to control the quality of the flow field The cascade has an improved effect, because the pressure difference required by this type of cascade is small, that is, the suction flow is small. However, for cascades that are more difficult to control, a greater suction pressure difference is required, that is, the suction flow rate. The increase in the suction flow rate will drive the fluid in the flow field of the test section to accelerate to the suction slot (suction port). When the width of the suction slit is constant and the flow rate increases to a certain level, the fluid at the suction slit will be blocked due to excessive acceleration, resulting in varying degrees of flow field deterioration at the suction port.

(3) At present, the diversion tailgate is mainly used in the test of the turbine cascade, and the fluid flow in the test section of the turbine blade cascade is a pressure gradient, so that the current application of the diversion tailgate does not consider the influence of the length of the tailgate. For the compressor cascade experiment, where the fluid flow is a reverse pressure gradient, it is necessary to comprehensively consider the coordination effect between the length of the tail plate and the angle of the tail plate; Tail plate adjustment, based on this structure, the adjustment stroke of the tail plate is small, does not have good universality, and the adjustment range is not accurate, and the effect of adjusting and improving the deteriorated flow field is not good; the existing tail plate adjustment methods are many It is a traction-type pull adjustment, and lacks the reading process of the tail plate angle, which leads to some tentativeness in each experimental process, which is not conducive to saving costs, and is also not conducive to the summary of the tail plate adjustment rules.

Contents of the invention

In view of this, the present invention aims to propose a system for improving the flow field quality of a plane cascade combined with a suction and a deflector tail plate, so as to solve the problem of deterioration of the flow field of the existing plane cascade test system.

In order to achieve the above object, technical solution of the present invention is achieved in that way:

A system for improving the flow field quality of a plane cascade combined with suction and deflector tail plate, including a fixed seat and a cascade test bench set on the fixed seat, one end of the cascade test bench is provided with an air supply pipe, and the other end is An exhaust port is provided, and a cascade test piece is provided in the middle of the cascade test bench; a left turntable and a right turntable are respectively arranged on the left and right sides of the cascade test bench, and the left turntable and the right turntable Both of them are rotatably installed on the cascade test bench, and there is an air guide gap connected with the air supply pipe between the left and right rotary discs; one side of the cascade test piece is set on the left rotary disc, and the other side is set on the right On the turntable, the cascade test piece includes a grid plate, and a test cascade is arranged on the grid plate, and two grid plates are set corresponding to the left turntable and the right turntable. The accommodating gap of the cascade, the accommodating gap communicates with the air guiding gap; one end of the cascade test piece facing the air supply pipe is provided with a suction mechanism, and the other end is provided with a flow guide mechanism.

Further, the suction mechanism includes a suction head provided on the cascade test piece corresponding to the front edge of the test cascade, and two suction heads are set corresponding to the upper and lower sides of the cascade test piece; One side of the middle part of the cascade test piece is provided with a suction port, and the suction head is provided with an adjustment assembly for adjusting the size of the suction port.

Further, the suction head includes an assembly plate provided on the grid plate, the side of the assembly plate facing the middle of the cascade test piece is provided with an L-shaped suction plate, and the other side is provided with a suction pipe; The vertical end of the suction plate is set on the assembly plate, and the horizontal end is set towards the front edge of the test cascade, a suction chamber is formed between the suction plate and the assembly plate, and the suction pipe communicates with the suction chamber; the An adjustment plate is provided on the assembly plate corresponding to the position between the suction plate and the front edge of the test cascade. The adjustment plate is slidably arranged on the assembly plate, and the adjustable gap between the adjustment plate and the horizontal end of the suction plate forms a Suction port.

Further, the horizontal ends of the adjustment plate and the suction plate are provided with curved surfaces on the side facing the suction port.

Further, the adjustment assembly includes an adjustment screw, the length direction of the adjustment screw is the same as the sliding direction of the adjustment plate; the adjustment plate is provided with an assembly hole matched with the adjustment screw, and the adjustment screw passes through the One end is arranged on the vertical end of the suction plate, and the other end is provided with an adjusting nut for pushing the adjusting plate to move.

Further, the deflector mechanism includes a tailgate set on the test piece of the cascade corresponding to the trailing edge of the test cascade, and two tailgates are arranged on the upper and lower sides of the test piece of the cascade, each of which One end of the deflector tail plate is rotated and installed on the blade cascade test piece, and the other end is provided with an adjustable telescopic plate.

Further, the deflector tail plate is installed on the grid plate through the rotating shaft, and the position of the left or right rotating disc corresponding to the rotating shaft is provided with an angle display plate, and the pointer on the angle display plate is connected with the rotating shaft. Shaft connection; the diversion mechanism also includes an angle adjustment rod for adjusting the angle of the diversion tail plate, and the angle adjustment rod is rotatably installed on the diversion tail plate.

Further, the guide tail plate is provided with a chute that slides and fits with the telescopic plate, the position of the guide tail plate corresponding to the chute is provided with a positioning piece, and the guide tail plate is provided with a The installation hole of the piece is connected with the chute; the expansion plate is provided with a positioning hole matched with the positioning piece, and at least two positioning holes are arranged at intervals along the sliding direction of the expansion plate.

Further, the tail plate static pressure hole is provided on the deflector tail plate, and the chord length of the test cascade is b; the tail plate static pressure hole is set corresponding to the trailing edge of the test cascade at 0.3b-1.5b, The static pressure holes of the tail plate are arranged at least two at intervals.

Further, the grid plate is provided with static pressure holes before the grid, the chord length of the test cascade is b, and the pitch is t; the static pressure holes in front of the grid correspond to the front edge of the test cascade 0.5b-1.5b There are at least three static pressure holes in front of the grid at intervals, and the interval between the static pressure holes in front of each grid is 0.2t-2t.

Compared with the prior art, a planar cascade flow field quality improvement system combined with suction and deflector tail plate according to the present invention has the following advantages:

The invention adopts the method of combining the suction mechanism and the flow guide mechanism to improve the quality of the cascade flow field, the improvement effect is good, the operation and adjustment are simple, and the accurate adjustment and improvement of the quality of the cascade flow field can be realized; The suction head is set at the position of the front edge, which has a better suction effect on the boundary layer. At the same time, by setting a movable adjustment plate on the suction head, the width of the suction port can be adjusted, which is beneficial to the deployment of different blades. The suction of the cascade test piece; by setting the diversion tail plate near the rear edge of the cascade test piece, it is beneficial to the fluid control behind the cascade, which conforms to the fluid flow law of the cascade. The diversion tail plate is a telescopic structure, and the flow guide The angle of the tail plate can be adjusted, and the guide tail plate can be adjusted in two stages according to the needs, which improves the accuracy of fluid control and adjustment behind the grid, and is conducive to the targeted tail plate adjustment for different blade cascade test pieces, which improves this The applicability and universality of the system to different cascade test pieces.

Description of drawings

The drawings constituting a part of the present invention are used to provide a further understanding of the present invention, and the schematic embodiments and descriptions of the present invention are used to explain the present invention, and do not constitute an improper limitation of the present invention. In the attached picture:

Fig. 1 is a schematic structural diagram of a system for improving the flow field quality of a plane cascade combined with suction and deflector tail plates according to an embodiment of the present invention;

Fig. 2 is a schematic structural diagram of a cascade test bench in a planar cascade flow field quality improvement system that combines suction and diversion tailgates according to an embodiment of the present invention;

Fig. 3 is a schematic structural diagram of a cascade test piece in a planar cascade flow field quality improvement system combining suction and diversion tailgate described in an embodiment of the present invention;

Fig. 4 is a schematic structural diagram of a flow guide mechanism in a planar cascade flow field quality improvement system that combines suction and guide tailgates according to an embodiment of the present invention;

Fig. 5 is a schematic diagram of the flow field quality corresponding to the width of the suction port in a planar cascade flow field quality improvement system combined with suction and guide tailgate according to an embodiment of the present invention;

Fig. 6 is a schematic diagram of the relative flow distribution of each channel of the test cascade in a system for improving the flow field quality of the plane cascade combined with suction and guide tailgate according to an embodiment of the present invention;

Fig. 7 is a schematic diagram of the adjustment rules of the tailgate in a planar cascade flow field quality improvement system combining suction and tailgate according to an embodiment of the present invention.

Explanation of reference signs:

1. Fixed seat; 2. Cascade test bench; 3. Air supply pipe; 4. Exhaust port; 5. Left turntable; 6. Rotation shaft; 7. Angle display panel; Right turntable; 10. Expansion plate; 11. Tail deflector; 12. Angle adjustment rod; 13. Test cascade; 14. Grid plate; 15. Suction pipe; 16. Assembly plate; 17. Suction plate; 18. Adjusting plate; 19. Suction port; 20. Positioning piece; 21. Adjusting screw; 22. Adjusting nut; 23. Arc surface; 24. Static pressure hole of tail plate; 25. Mounting hole;

Detailed ways

It should be noted that, in the case of no conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

In describing the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", " The orientations or positional relationships indicated by "vertical", "horizontal", "top", "bottom", "inner" and "outer" are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and Simplified descriptions, rather than indicating or implying that the device or element referred to must have a particular orientation, be constructed and operate in a particular orientation, and thus should not be construed as limiting the invention. In addition, the terms "first", "second", etc. are used for descriptive purposes only, and should not be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, a feature defined as "first", "second", etc. may expressly or implicitly include one or more of that feature. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

In the description of the present invention, it should be noted that unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection. Connected, or integrally connected; it can be mechanically connected or electrically connected; it can be directly connected or indirectly connected through an intermediary, and it can be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention based on specific situations.

The present invention will be described in detail below with reference to the accompanying drawings and examples.

A planar cascade flow field quality improvement system combined with suction and guide tailgate, as shown in Figures 1 to 4, includes a fixed seat 1, and a cascade test bench 2 set on the fixed seat 1, said One end of the cascade test bench 2 is provided with an air supply pipe 3, and the other end is provided with an exhaust port 4. The cascade test piece is provided in the middle of the cascade test bench 2; The left turntable 5 and the right turntable 9 are both rotatably installed on the cascade test bench 2, and there is a gas supply pipe 3 between the left turntable 5 and the right turntable 9. Air guide gap; the inside of the cascade test bench 2 is a cavity body structure, and a turntable slideway for installing the left turntable 5 and the right turntable 9 can be set on the cascade test stand 2, so as to realize the left turntable 5 and the right turntable. The stable rotation of the right turntable 9 on the cascade test bench 2, the structure of the left turntable 5 and the right turntable 9 are the same, the rotation direction is the same, and can be rotated synchronously to realize the angle adjustment of the cascade test piece, Meet various test requirements of cascade test pieces.

One side of the cascade test piece can be set on the left turntable 5, and the other side is set on the right turntable 9, the cascade test piece includes a grid plate 14, and a test cascade 13 is arranged on the grid plate 14, There are two grid plates 14 corresponding to the left turntable 5 and the right turntable 9, and there is an accommodating gap between the two grid plates 14 for accommodating the test cascade 13, and the accommodating gap communicates with the air guide gap; optional The test cascade 13 is installed and fixed between the left and right grid plates 14, and a plurality of fixed positions for installing and fixing the test cascade 13 can be arranged on the grid plate 14. For example, the test cascade 13 can be spaced apart on the grid plate 14. Set six, the grid plate 14 can be provided with fixing holes for fixing the test blade cascade 13; the grid plate 14 can be installed and fixed on the turntable by screws, so as to realize the stable setting of the blade cascade test piece on the turntable and ensure that the turntable can Drive the blade cascade test piece to rotate stably.

One end of the cascade test piece facing the air supply pipe 3 is provided with a suction mechanism, and the other end is provided with a flow guide mechanism; the suction mechanism includes a suction head provided on the cascade test piece corresponding to the front edge of the test cascade 13, Two suction heads are arranged on the upper and lower sides of the cascade test piece; the suction head is provided with a suction port 19 on the side facing the middle of the cascade test piece, and the suction head is provided with a suction port for adjusting The adjustment assembly of suction port 19 size.

In the actual test process, the test cascade 13 is a compressor blade or a turbine blade, and multiple test cascades 13 can be arranged at intervals. By setting two suction heads corresponding to the upper and lower sides of the cascade test piece, the test blade The front edge of grid 13 forms the upper end wall suction cavity and the lower end wall suction cavity; when the experimental fluid flows into the cascade test bench 2 through the air supply pipe 3, a low-energy boundary layer will be generated on the upper and lower end walls of the cascade test bench 2 inlet section; the low-energy The fluid continues to move forward, and then, driven by the pressure difference between the upper end wall suction chamber and the lower end wall suction chamber, the low-energy fluid is sucked into the upper and lower suction ports at the suction ports 19 of the upper end wall suction head and the lower end wall suction head. In the lower two suction heads, the adjustment of the uniformity of the flow field in front of the grid can be realized; by setting the upper and lower suction heads, it can better meet the needs of adjusting the uniformity of the flow field in front of the grid, and improve this Systematic process quality improvement effect.

The suction head includes an assembly plate 16 provided on the grid plate 14, the side of the assembly plate 16 facing the middle of the cascade test piece is provided with an L-shaped suction plate 17, and the other side is provided with a suction pipe 15; The vertical end of the suction plate 17 is arranged on the assembly plate 16, and the horizontal end is arranged toward the front edge of the test cascade 13. A suction cavity is formed between the suction plate 17 and the assembly plate 16. The suction pipe 15 It communicates with the suction cavity; the position between the corresponding suction plate 17 and the front edge of the test cascade 13 is provided with an adjustment plate 18 on the assembly plate 16, and the adjustment plate 18 is slidably arranged on the assembly plate 16, and the adjustment The adjustable gap between the plate 18 and the horizontal end of the suction plate 17 forms a suction opening 19 . The adjustment assembly includes an adjustment screw 21, the length direction of the adjustment screw 21 is the same as the sliding direction of the adjustment plate 18; the adjustment plate 18 is provided with an assembly hole matched with the adjustment screw 21, and the adjustment screw 21 passes One end of the assembly hole is arranged on the vertical end of the suction plate 17, and the other end is provided with an adjusting nut 22 for pushing the adjusting plate 18 to move.

Optionally, the assembly plate 16 can be installed and fixed on the grid plate 14 by screws, the adjusting screw 21 can be welded and fixed on the vertical end of the suction plate 17, and the adjusting screw 21 is horizontally arranged on the vertical end of the suction plate 17 ;By screwing the adjusting nut 22, utilizing the adjusting nut 22 to cooperate with the adjusting screw rod 21, the adjusting plate 18 can be promoted to move to the suction plate 17 side, so as to realize the adjustment of the size (width) of the suction port 19, by adjusting the suction The size of the port 19 can adjust the suction flow rate of the suction head to meet the requirements of different optimal suction port 19 widths corresponding to different cascade experiments. Since the adjustment assembly for adjusting the width of the suction port 19 is provided, even if the flow rate increases to a certain extent, the fluid can pass through smoothly by adjusting the width of the suction port 19, avoiding the suction port 19 caused by the excessive acceleration of the fluid. Occurrence of blockage prevents turbulent flow, thereby improving the quality of the flow field at the position of the suction port 19, so that this system can meet the test requirements of different cascade test pieces.

Optionally, in order to improve the stability of the adjusting plate 18 on the adjusting screw 21, adjusting nuts 22 can be provided on the adjusting screw 21 corresponding to the left and right sides of the adjusting plate 18, and the adjusting nuts 22 are used to clamp and fix the adjusting plate 18, can realize the stable setting of the adjusting plate 18 on the adjusting screw 21, improve the stability of the suction port 19 when the fluid flows through the adjusting plate 18, and prevent the suction head from moving due to the adjusting plate 18 during the suction process , resulting in a change in the size of the instantaneous suction port 19, which is beneficial to ensure that the cascade flow field can always meet the test requirements stably.

The side of the regulating plate 18 and the horizontal end of the suction plate 17 facing the suction port 19 is provided with an arc surface 23; the arc surface 23 can reduce the resistance of the regulating plate 18 and the horizontal end of the suction plate 17 to the fluid, and improve the suction. The suction effect and suction efficiency of the head are beneficial to reduce the influence of the suction fluid blockage on the smooth quality; compared with the right angle or other angle surfaces, the arc surface 23 can guide the fluid to flow smoothly into the suction port 19, and then through the suction tube 15 discharge, the arc surface 23 on the horizontal end of the adjustment plate 18 and the suction plate 17 can make the suction port 19 form a similar trumpet-shaped opening, which is more conducive to the entry and convergence of fluid, and the fluid is not easy to flow at the suction port 19 When the deflection occurs, it is less likely to be disturbed at the suction port 19, ensuring that the fluid can enter the suction head more continuously and smoothly, which is conducive to further improving the quality of the flow field at the suction port 19, and ensuring that the suction port 19 has different widths. The flow field below remains stable.

The deflector mechanism includes a tailgate 11 corresponding to the trailing edge of the test blade cascade 13 on the cascade test piece, and two tailgates 11 are arranged on the upper and lower sides of the cascade test piece, each of which One end of the guide tail plate 11 is rotatably installed on the blade cascade test piece, and the other end is provided with an adjustable telescopic plate 10 . The guide tail plate 11 is provided with a chute that is slidingly matched with the telescopic plate 10, and the position corresponding to the chute on the guide tail plate 11 is provided with a positioning member 20, and the guide tail plate 11 is provided with a Install the mounting hole 25 of the positioning member 20, the mounting hole 25 communicates with the chute; Set two.

Optionally, the positioning member 20 can adopt positioning pins or positioning screws, and each positioning hole 26 can be linearly arranged on the left and right sides of the expansion plate 10, so as to improve the stability of the expansion plate 10 on the tail plate 11; 20 can pass through the installation hole 25 and the positioning hole 26 in sequence to realize the limit and fixation of the telescopic plate 10, and by setting a plurality of positioning holes 26, the adjustment of the length of the stretching chute of the telescopic plate 10 can be realized; The length of the plate 10 can change the overall length of the tail plate 11, and then realize the adjustment of the flow state of the flow guide channel between the two tail plates 11, thereby affecting the quality of the flow field and improving the flow field of the cascade.

The diversion tailgate 11 can be divided into an upper tail diversion tailgate and a lower tail diversion tailgate. Two diversion tailgates 11 are arranged on the upper and lower sides of the cascade test piece, and the two diversion tailgates 11 A fluid test outlet section can be formed between them; after the fluid is sucked by the suction mechanism, it flows through the cascade test piece, and then flows into the experimental outlet section containing the upper and lower tail guide tail plates. Under the adjustment of the diversion tail plate 11, it flows out of the cascade test bench 2 according to the required direction; the experimental outlet section formed by the two diversion tail plates 11 can realize the adjustment of the outflow direction of the experimental fluid, and then realize the adjustment of the cascade flow. Adjustment of the field; using the mutual cooperation of the suction mechanism and the flow guide mechanism, by reducing the generation of turbulent flow at the suction mechanism, the state of the fluid entering the cascade test piece can be effectively improved, and then guided by the flow guide mechanism, the fluid can be smoothly Through each cascade channel, the synchronous adjustment of the fluid in the inlet section and outlet section of the experiment can be realized, which is conducive to further improving the quality of the flow field of the plane cascade.

The guide tailgate 11 can be rotated and installed on the grid plate 14 through the rotating shaft 6, and the position corresponding to the rotating shaft 6 on the left rotating disk 5 or the right rotating disk 9 is provided with an angle display disk 7, and the angle display disk The pointer on 7 is connected to the rotating shaft 6; the guide mechanism also includes an angle adjustment rod 12 for adjusting the angle of the guide tail plate 11, and the angle adjustment rod 12 is rotatably mounted on the guide tail plate 11.

Optionally, a through hole for installing the rotating shaft 6 may be provided on the grid plate 14, and a through hole cooperating with the rotating shaft 6 may also be provided on the left turntable 5 and the right turntable 9, so as to realize that the guide tailgate 11 The stable rotation on the grid plate 14 can realize the cooperation between the rotating shaft 6 and the angle display disc 7 at the same time, the angle display disc 7 can be provided with a rotating hole matched with the rotating shaft 6, and the end of the rotating shaft 6 passing through the rotating hole is provided with a pointer , the pointer can be welded and fixed on the rotation shaft 6; the angle display panel 7 is used to display the rotation angle of the tail plate 11, which is convenient for the operator to accurately adjust the angle of the tail plate 11 according to the experimental needs, and is conducive to improving the reliability of this system Operability and operational accuracy; moreover, the operator can also summarize the rules according to the rotation angle of the diverter tail plate 11 displayed on the angle display panel 7, which is conducive to improving the convenience of using this improved system.

Optionally, in order to reduce the loss of fluid, the left and right sides of the diversion tail plate 11 can be arranged close to the grid plate 14 to ensure that the diversion tail plate 11 can effectively guide the fluid to flow out through the experimental outlet section; The left and right sides can also be arranged close to the grid plate 14 to achieve sufficient suction of the fluid and reduce the generation of turbulent flow.

Optionally, the angle adjusting rod 12 can be a hollow structural member, and one end of the angle adjusting rod 12 can be rotated and installed on the tailgate 11 through a rotating shaft, and the other end can be connected to an external driving device, such as an electric push rod, etc., to realize driving The diversion tail plate 11 rotates; when the angle of the diversion tail plate 11 needs to be adjusted, the angle adjustment rod 12 can be pulled to drive the diversion tail plate 11 to rotate to a suitable angle, which is easy to operate; the angle adjustment rod 12 with a hollow structure , the angle adjustment rod 12 can also be connected to the suction equipment through a connecting pipe, and the cavity of the angle adjustment rod 12 can be used for fluid suction, which is convenient for the tail plate suction activity for the turbine blade cascade test piece, which is conducive to improving the applicability of this system sex.

The tail plate static pressure hole 24 is provided on the diversion tail plate 11, and the tail plate static pressure hole 24 is set at 0.3b-1.5b corresponding to the rear edge of the test blade grid 13, and the tail plate static pressure hole 24 is at least Set two. The grid plate 14 is provided with static pressure holes 8 in front of the grid, and the static pressure holes 8 in front of the grid are set at 0.5b-1.5b corresponding to the front edge of the test cascade 13; the static pressure holes 8 in front of the grid are arranged at least three times apart. The interval between the static pressure holes 8 in front of each grid is 0.2t-2t; wherein, b is the chord length of the test cascade 13; t is the pitch of the test cascade 13.

The static pressure display of the static pressure hole 8 in front of the grid can be used to judge the uniformity of the fluid in front of the grid. When the static pressures of the static pressure holes in different positions of the fluid in front of the grid are consistent, it is judged that the uniformity in front of the grid meets the requirements; Both the tail plate static pressure hole 24 can be set on the tail plate and the lower end diversion tail plate. During the experiment, the static pressure of the upper tail end diversion tail plate static pressure hole and the lower tail end diversion tail plate static pressure hole can be compared. Clarify the effect of adjusting the length and angle of the diversion tail plate 11 on the periodical improvement of the flow field behind the grid; the tail plate static pressure holes 24 on the upper and lower tail diversion tail plates can be arranged linearly, and can be compared by comparing the upper and lower Corresponding to the static pressure value at the position of the static pressure hole 24 of the tail plate, the periodicity of the outlet flow field is judged. In periodic state, its static pressure value should be consistent.

The present invention provides a system for improving the flow field quality of a plane cascade combined with suction and diversion tailgate. It is found through tests that the width of the suction slot (suction port) affects the quality of the flow field. Figure 5 shows P3- The comparison diagram of the axial density flow ratio of P7 channel is shown in Figure 5, wherein the five points in the abscissa represent the P3-P7 channel (the channel formed between the test blades), and the ordinate represents the axial density of each channel. The value of the flow ratio; the figure shows that the axial dense flow ratio of the original scheme gradually decreases along the pitch direction, but the difference between the dense flow ratios of each channel is large; under the same suction flow conditions, the suction gaps of 10mm, 20mm, and 30mm Compared with the original scheme, the axial dense flow ratio of the scheme is reduced, and the axial dense flow ratio between the channels is more uniform. When the suction slot width is 20mm, it has a better performance of the axial dense flow ratio. Different cascade experiments correspond to different optimal suction slit widths, which requires the suction slit width to be adjustable. Therefore, the system meets the experimental requirements of different cascade experiments by adjusting the width of the suction slit, and has a good applicability and universality.

Specifically, the present invention needs to reasonably adjust the width of the suction slot by setting an adjustable suction head when testing different cascades; wherein the suction slot of the upper end wall suction head and the lower end wall suction head The suction slots are adjusted in the same way, and the adjusting nut on the adjusting screw can be used to adjust the left and right strokes of the adjusting plate, and change the size of the suction port to realize the adjustment of the width of the suction slot (suction port); The adjustable position of the adjusting plate can be set close to the front edge of the test cascade, so as to improve the suction effect of the suction head on the fluid.

The adjustment of the diversion tail plate to the relative flow of each channel is shown in Figure 6. In the original scheme, the flow into the P1 channel is smaller than that of other channels, and at this time, the P1 channel is blocked. In the diversion tail plate scheme adopted in the present invention, the relative flow of P7 and P8 channels decreases, wherein the flow of P8 channel is significantly smaller than other channels, and the flow of flow into P4, P5, and P6 channels is significantly improved, and P4, P5, and P6 The period of the channel is better, because the blockage effect of the P1 and P8 channels will squeeze the fluid on the upper and lower sides to the middle channel, thereby increasing the flow rate of the P4, P5, and P6 channels, and improving the periodicity of the cascade flow field.

Specifically, the present invention can further improve the fluent quality of the blade cascade by setting the deflector mechanism; for example, it has been found through experiments that the law between the angle/length and the effect of the deflector at the lower tail end is shown in Figure 7, where ( a) The figure shows the angle adjustment law of the diverter tail plate, where 0° represents the outlet geometric angle of the experimental outlet section formed by the diverter tail plate, +3° means the upward deflection of 3° from the outlet geometric angle, and -1.5° means the outlet geometric angle The angle is deflected downward by 1.5°; the figure (b) shows the regulation of the length of the deflector tail plate, where 1b is expressed as one chord length, and so on.

It can be seen from (a) in Figure 7 that the angle of the diversion tail plate at the lower end is deflected from bottom to top, which will adjust the flow state of the 2-3 channels at the lower end, and the flow state of the channel will affect the uniformity of the flow field in front of the grid , so that the uniformity of the flow field in front of the grid is adjusted in different degrees, the angle is deflected from bottom to top (from -6° to +3°), and the uniformity of the flow field in front of the grid first increases and then decreases.

It can be seen from (b) in Figure 7 that the length of the diversion tail plate gradually increases, which will also affect the flow state of the channel, thereby affecting the quality of the flow field; comparing (a) and (b), it can be seen that the diversion tail plate The effect of the angle adjustment is more obvious than that of the length adjustment. Therefore, the overall length adjustment of the tail vane can be used as a fine-tuning after the angle adjustment to realize the unadjusted flow field of the blade cascade; If the influence effect is insufficient to meet the improvement effect of the cascade flow field, the operator can further improve the quality of the cascade flow field by adjusting the overall length of the tail plate. Compared with the prior art, the present invention adopts coarse adjustment The method combined with fine adjustment can realize the precise adjustment of the quality of the cascade flow field, which is beneficial to further improve the effect of improving the quality of the cascade flow field.

Component position changes in the working process of the present invention:

When testing different test cascades, it is necessary to reasonably adjust the width of the suction slot (suction port); the suction port of the upper end wall suction head is adjusted in the same way as the suction port of the lower end wall suction head, both The adjustable component can be used to adjust the left and right strokes of the movable wall plate, so as to realize the adjustment of the width of the suction slot (suction port);

The adjustment of the overall length of the outlet diversion tail plate is adjusted by using the expansion plate set on the diversion tail plate; there is a positioning piece on the diversion tail plate for positioning the length of the expansion plate, which can be adjusted with the positioning hole on the expansion plate Cooperate to realize the fixation of the extension or shortening of the telescopic rod;

The adjustment of the diversion tailgate angle is completed by the cooperation of two parts. First, there are rotatable rotation shafts at the root of the upper tail diversion tailgate and the lower tail diversion tailgate. Secondly, the upper tail diversion tailgate and the lower tailgate The upper part of the tail end guide tailboard is hinged with the upper tailgate angle adjustment rod and the lower tailgate angle adjustment rod, the adjustment rod can be a telescopic rod, and the bottom is a rotatable ball-type turn baht; The rotating shaft of the diversion tail plate rotates to drive the tail plate to rotate, and the adjustment rod on the upper side of the tail plate is fixed and rotated to realize the adjustment of the angle of the tail plate; the rotation shaft at the root of the tail plate is inserted and fixed On the angle display panel on the left grid plate, the angle pointer can be welded on the rotating shaft, so as to achieve the purpose of quantitative adjustment of the angle of the diversion tail plate, and it is convenient for the operator to check the angle adjustment of the diversion tail plate.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of the present invention. within the scope of protection.

Claims

A system for improving the quality of a plane cascade flow field combined with suction and diversion tailgate, characterized in that it includes a fixed base (1) and a cascade test bench (2) set on the fixed base (1), the One end of the cascade test bench (2) is provided with an air supply pipe (3), and the other end is provided with an exhaust port (4), and the middle part of the cascade test bench (2) is provided with a cascade test piece; A left turntable (5) and a right turntable (9) are correspondingly provided on the left and right sides of the table (2), and the left turntable (5) and the right turntable (9) are both rotatably mounted on the cascade test bench (2 ), there is an air guide gap connected with the air supply pipe (3) between the left turntable (5) and the right turntable (9); one side of the cascade test piece is set on the left turntable (5), and the other One side is arranged on the right turntable (9), and the cascade test piece comprises a grid plate (14), and a test cascade (13) is arranged on the grid plate (14), and the grid plate (14) corresponds to turning left There are two disks (5) and right turntable (9), and there is an accommodating gap for accommodating the test blade cascade (13) between the two grid plates (14), and the accommodating gap communicates with the air guide gap; the One end of the cascade test piece facing the air supply pipe (3) is provided with a suction mechanism, and the other end is provided with a flow guide mechanism.
A system for improving the flow field quality of a plane cascade combined with suction and guide tailgate according to claim 1, characterized in that: the suction mechanism includes a corresponding test cascade (13) on the cascade test piece The suction head arranged on the front edge, two of the suction heads are arranged on the upper and lower sides of the cascade test piece; the suction head is provided with a suction port (19) toward the middle part of the cascade test piece, The suction head is provided with an adjustment assembly for adjusting the size of the suction port (19).
A system for improving the flow field quality of a plane cascade combined with suction and deflector tail plates according to claim 2, characterized in that: the suction head includes an assembly plate (16) set on the grid plate (14) ), the side of the assembly plate (16) facing the middle part of the cascade test piece is provided with an L-shaped suction plate (17), and the other side is provided with a suction pipe (15); the suction plate (17) The vertical end is arranged on the assembly plate (16), and the horizontal end is arranged towards the front edge of the test cascade (13). A suction cavity is formed between the suction plate (17) and the assembly plate (16). The pipe (15) communicates with the suction chamber; an adjustment plate (18) is provided at the position between the corresponding suction plate (17) and the front edge of the test cascade (13) on the assembly plate (16), and the adjustment plate (18) is slidably arranged on the assembly plate (16), and the adjustable gap between the adjustment plate (18) and the horizontal end of the suction plate (17) forms a suction port (19).
A system for improving the flow field quality of a plane cascade combined with suction and deflector tail plates according to claim 3, characterized in that: the horizontal ends of the adjustment plate (18) and the suction plate (17) face the suction One side of the suction port (19) is provided with an arc surface (23).
A system for improving the flow field quality of a plane cascade combined with suction and deflector tail plates according to claim 3, characterized in that: the adjustment assembly includes an adjustment screw (21), and the adjustment screw (21) The length direction of the adjustment plate (18) is the same as the sliding direction; the adjustment plate (18) is provided with an assembly hole matched with the adjustment screw (21), and one end of the adjustment screw (21) passing through the assembly hole is arranged on the On the vertical end of the suction plate (17), the other end is provided with an adjusting nut (22) for pushing the adjusting plate (18) to move.
A system for improving the flow field quality of a plane cascade combined with suction and deflector tail plate according to claim 1, characterized in that: said deflector mechanism includes a corresponding test cascade (13) on the cascade test piece A tailgate (11) arranged at the trailing edge, two tailgates (11) are arranged on the upper and lower sides of the blade cascade test piece, each of the tailgates (11) is rotated at one end and installed on the On the cascade test piece, the other end is provided with an adjustable telescopic plate (10).
A system for improving the quality of the flow field of a plane cascade combined with suction and diversion tailgate according to claim 6, characterized in that: the diversion tailgate (11) is rotatably installed on the shaft (6) On the grid plate (14), an angle display panel (7) is provided at the position corresponding to the rotation axis (6) on the left turntable (5) or the right turntable (9), and the angle display panel (7) on the angle display panel (7) The pointer is connected with the rotating shaft (6); the diversion mechanism also includes an angle adjustment rod (12) for adjusting the angle of the diversion tail plate (11), and the angle adjustment rod (12) is rotatably installed on the diversion tail plate (11) on.
According to claim 6, a plane cascade flow field quality improvement system combining suction and diversion tail plate, characterized in that: said diversion tail plate (11) is provided with a telescopic plate (10) A chute that slides and fits, a positioning piece (20) is provided on the position corresponding to the chute on the guide tail plate (11), and a mounting bracket (20) for installing the positioning piece (20) is provided on the guide tail plate (11). hole (25), the mounting hole (25) communicates with the chute; the telescopic plate (10) is provided with a positioning hole (26) matched with the positioning piece (20), and the positioning hole (26) is At least two boards (10) are arranged at intervals in the sliding direction.
According to claim 6, a plane cascade flow field quality improvement system combining suction and diversion tail plate, characterized in that: said diversion tail plate (11) is provided with a tail plate static pressure hole ( 24), the chord length of the test cascade (13) is b; the tail plate static pressure hole (24) is set at 0.3b-1.5b corresponding to the trailing edge of the test cascade (13), and the tail plate static pressure At least two holes (24) are arranged at intervals.
A system for improving the flow field quality of a plane cascade combined with suction and deflector tail plate according to claim 1, characterized in that: said grid plate (14) is provided with a static pressure hole (8) before the grid , the chord length of the test cascade (13) is b and the pitch is t; the static pressure holes (8) in front of the cascade are set at 0.5b-1.5b corresponding to the leading edge of the cascade cascade (13), and the cascade At least three front static pressure holes (8) are arranged at intervals, and the interval between the front static pressure holes (8) of each grid is 0.2t-2t.