Flow guide device of turbine rotor blade tenon

Abstract

The invention belongs to the technical field of aero-engines, and provides a turbine rotor blade tenon flow guiding device which comprises a blade tenon and a high-pressure backflow cavity communicated with the blade tenon, a plurality of channels are formed in one plane of the blade tenon and communicated with the high-pressure backflow cavity, a flow guiding table is arranged on one plane of the blade tenon, and a flow guiding groove is formed in the other plane of the blade tenon and communicated with the high-pressure backflow cavity. The flow guide table is close to the corresponding channel, an air inlet face and a flow guide face are arranged on the two adjacent side faces of the flow guide table respectively, the air inlet face is close to the air inlet of the blade tenon, and the flow guide face is located above the corresponding channel. Resistance and vortex can be reduced through the flow guide tables, so that the cold air flow of the corresponding channels is increased, the cold air flow of the corresponding channels flowing into the high-pressure backflow cavity is increased, the flow speed is increased, and the front ends of the blades are prevented from being violently impacted. A large vortex system is formed at the position of the channel far away from the flow guide table, so that the flow speed of cold air at the inlet of the channel is reduced, reasonable distribution of airflow in each channel is achieved, and the problem that the performance of an engine is affected due to excessive cold air consumption is avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of aeroengines, and in particular relates to a flow guide device for a turbine rotor blade tenon. Background Art

[0002] The cooling method of turbine blades in aircraft engines is usually a combination of film cooling and internal channel cooling. The principle of film cooling is that the cooling airflow passes through the gaps or cooling holes machined on the turbine blades, evenly covers the blade surface, forming a layer of air thermal resistance, which hinders the direct heat transfer between the high-temperature combustion gas and the blade surface. Internal channel cooling means that the cooling airflow flows in the cooling channel inside the blade, performs convective heat exchange and removes heat. At the same time, in order to enhance the heat exchange effect, spoiler structure units and impact holes are usually added to enhance heat exchange.

[0003] However, the above-mentioned turbine rotor blade cooling structure is leading edge impact + blade body air film + column rib turbulence, etc. When the turbine rotor blades are directly impacted by high-temperature and high-pressure combustion gas, edge ablation is prone to occur at the leading edge of the blade and the blade basin near the leading edge. The leading edge air supply cavity and the ribbed channel in the middle of the blade body have little potential for improving the heat exchange capacity. In order to effectively thermally protect the leading edge of the blade and the blade basin near the leading edge, a large amount of cold air and a greater cold air pressure loss are required to increase the inner cavity heat transfer coefficient, and excessive use of cold air will seriously affect the performance of the engine. Summary of the invention

[0004] In view of the above problems, the present invention proposes a flow guide device for a turbine rotor blade tenon, comprising: a blade tenon and a high-pressure reflux chamber connected to the blade tenon, a plurality of channels are opened on a plane of the blade tenon, each of the channels is respectively connected to the high-pressure reflux chamber, a flow guide platform is provided on a plane of the blade tenon, the flow guide platform is close to the corresponding channel, an air intake surface and a flow guide surface are respectively provided on two adjacent side surfaces of the flow guide platform, the air intake surface is close to the air intake inlet of the blade tenon, and the flow guide surface is located above the corresponding channel.

[0005] Optionally, the projection of the air inlet surface onto the X direction of the reference point forms an angle α, the angle α is between 8° and 15°, and the reference point is the center point of the blade.

[0006] Optionally, the axial direction of the guide surface forms an angle β with the Y direction of the reference point, and the angle β is 35° to 50°.

[0007] Optionally, the distance between the dividing line on the guide surface and the reference point of the blade tenon is a, and the distance a is between 1.5 mm and 2 mm.

[0008] Optionally, the distance between the end of the air inlet surface and one side edge of the blade tenon is c, and the distance c is between 1.5 mm and 2.5 mm.

[0009] Optionally, the height of the guide platform is d, and the height d is between 2 mm and 3 mm.

[0010] Optionally, there are three channels, which are connected to the high-pressure reflux chamber respectively.

[0011] Optionally, the high-pressure reflux chamber includes a first cavity, a second cavity, a third cavity and a fourth cavity, two adjacent channels are respectively connected to the second cavity, the other channel is connected to the third cavity, the first cavity is connected to the second cavity, and the third cavity is connected to the fourth cavity.

[0012] Optionally, a plurality of air film holes are provided on one side wall of the first cavity, and a plurality of ventilation holes are provided on the other side wall of the first cavity to connect the first cavity and the second cavity.

[0013] Optionally, the second cavity is an L-shaped structure and is provided with a plurality of exhaust holes at its end, and the outlet end of the fourth cavity is provided with a plurality of offset slits.

[0014] The guide device of the turbine rotor blade tenon of the present invention has the following advantages compared with the prior art: by providing a guide platform and an air inlet surface on a plane of the blade tenon, the cooling airflow can be guided into the corresponding channel, and the guide surface on the guide platform can play a role in stabilizing the flow, so that the vortex system generated by the guide platform close to the corresponding channel is reduced, thereby increasing the cold air flow rate flowing into the high-pressure reflux chamber from the channel here, and at the same time, a larger vortex system is formed at the corresponding channel position at the end away from the guide platform, the cold air flow velocity at the channel inlet is reduced, and the cold air flow entering this channel is reduced, thereby affecting the cold air flow distribution of multiple channels, making the cold air flow distribution more reasonable, and avoiding the problem of serious impact on engine performance due to excessive cold air consumption.

[0015] Other features and advantages of the present invention will be described in the following description, and partly become obvious from the description, or be understood by implementing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1A schematic diagram of a flow guide device for a turbine rotor blade tenon in an embodiment of the present invention is shown;

[0018] Figure 2 A schematic diagram showing the flow direction of the inner cavity airflow of the flow guide device of the tenon of the turbine rotor blade in the embodiment of the present invention is shown;

[0019] Figure 3 A schematic diagram of the inner cavity of a flow guide device of a turbine rotor blade tenon in an embodiment of the present invention is shown;

[0020] Figure 4 A schematic diagram showing a reference point of a flow guide device of a turbine rotor blade tenon and an XY coordinate diagram of the blade tenon in an embodiment of the present invention is shown;

[0021] Figure 5 A schematic diagram showing a reference point of a guide device of a turbine rotor blade tenon and a ZY coordinate diagram of the blade tenon in an embodiment of the present invention is shown;

[0022] Figure 6 Another schematic diagram of a guide platform of a guide device for a turbine rotor blade tenon in an embodiment of the present invention is shown;

[0023] Figure 7 A schematic diagram of the inlet flow field of the flow guide device of the tenon of the turbine rotor blade in an embodiment of the present invention is shown.

[0024] In the figure, 1. blade tenon; 11. channel; 2. high-pressure reflux chamber; 21. first cavity; 22. second cavity; 23. third cavity; 24. fourth cavity; 211. air film hole; 212. vent hole; 221. exhaust hole; 241. split gap; 3. guide platform; 31. air inlet surface; 32. guide surface; 33. air back surface; 34. dividing line; 311. first air inlet rounded corner surface; 312. first air inlet inclined surface; 331. second air inlet rounded corner surface; 332. second air inlet inclined surface. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] like Figure 2 As shown, the present invention provides a turbine rotor blade tenon flow guide device, comprising: a blade tenon 1 and a high-pressure return chamber 2 connected to the blade tenon 1, a plurality of channels 11 are opened on a plane of the blade tenon 1, and each channel 11 is connected to the high-pressure return chamber 2, such as Figure 1 As shown, a guide platform 3 is provided on a plane of the blade tenon 1, and the guide platform 3 is close to the corresponding channel 11. An air inlet surface 31 and a guide surface 32 are respectively provided on two adjacent sides of the guide platform 3. The air inlet surface 31 is close to the air inlet entrance of the blade tenon 1, and the guide surface 32 is located above the corresponding channel 11. The guide platform 3 can reduce drag and vortex, that is, reduce the vortex system on the corresponding channel 11 of the guide platform 3, so that the cold air flow of the corresponding channel 11 increases, the cold air flow of the corresponding channel 11 into the high-pressure reflux chamber 2 is increased, the flow rate is accelerated, and the cold air flow is reasonably distributed, thereby avoiding severe impact on the front end of the blade and implementing precise thermal protection. A larger vortex system is formed at the position of the channel 11 far away from the guide platform 3, so that the cold air flow rate at the entrance of the channel 11 is reduced, and the temperature of the low-temperature zone in the middle section of the blade is increased, so that the reasonable distribution of the air flow in each channel 11 is achieved, and the problem of excessive cold air consumption seriously affecting the performance of the engine is avoided. Optionally, the shape of the guide platform 3 is approximately bird-beak-shaped, which facilitates guiding the airflow direction, reduces the maximum temperature of the entire blade and the average temperature of the blade, increases the temperature of the low-temperature zone in the middle of the blade, reduces the temperature gradient of the blade, and increases the service life of the blade.

[0027] like Figure 4 As shown, in one embodiment, the inlet surface 31 is projected to the reference point X direction to form an angle α, and the angle α is between 8° and 15°, and the reference point is the center point of the blade. Specifically, α is 10°. Through the appropriate α angle range, the inlet surface 31 can most effectively guide the gas into the corresponding channel 11, thereby reasonably increasing the gas entering the corresponding channel 11, and reasonably distributing the gas flowing into each channel 11. Figure 6 As shown, optionally, the air intake surface 31 is rounded to form a first air intake rounded surface 311 and a first air intake inclined surface 312, and the fillet radius of the first air intake rounded surface 311 is in the range of 0.5 to 1.2 mm, and specifically, the fillet radius is 1 mm. The other end surface of the back air surface 33 away from the guide platform 3 is also rounded to form a second air intake rounded surface 331 and a second air intake inclined surface 332, and the fillet radius is in the range of 0.5 to 1.2 mm, and specifically, the fillet radius is 1 mm.

[0028] In one embodiment, the axial direction of the guide surface 32 forms an angle β with the reference point Y direction, and the angle β is 35° to 50°. Specifically, β is 40°. Through the appropriate angle β, the guide surface 32 can more stably guide the gas flowing into the corresponding channel 11. The mutual cooperation between the guide surface 32 and the air intake surface 31 makes the vortex system generated in the channel 11 corresponding to the guide platform 3 smaller, which can increase the air intake in the channel 11 corresponding to the guide platform 3, and the vortex system generated in the channel 11 away from the guide platform 3 becomes larger, and the air intake in the channel 11 is reduced, thereby reasonably distributing the air intake of each channel 11. Figure 4 As shown, optionally, the outer radius R of the guide platform 3 is consistent with the arc radius of the bottom of the tenon, and the outer radius R of the guide platform 3 is 2.7 mm.

[0029] like Figure 1 As shown, in one embodiment, the center distance between the dividing line 34 on the guide surface 32 and the reference point of the blade tenon 1 is a. Figure 4 As shown, the distance a is between 1.5 mm and 2 mm. Specifically, a is 2 mm. Through a suitable a, the guide surface 32 can also guide the gas flowing into the corresponding channel 11 more stably, and effectively guide the gas flow to be reasonably distributed into the corresponding channel 11. It should be noted that the dividing line 34 separates the guide surface 32 and the other end adjacent to the guide surface 32. The end surface can block part of the airflow to prevent the airflow from being lost, thereby forming a vortex system.

[0030] In one embodiment, the distance between the end of the air inlet surface 31 and one side of the blade is c, and the distance c is between 1.5 mm and 2.5 mm. Specifically, c is 2 mm. Through a suitable c, the gas flow entering the corresponding channel 11 can be more efficiently and reasonably guided and distributed. The maximum temperature of the entire blade and the average temperature of the blade are reduced, the temperature of the low temperature zone in the middle of the blade is increased, the temperature gradient of the blade is reduced, and the service life of the blade is increased.

[0031] like Figure 2 As shown, in one embodiment, the height of the guide platform 3 is d, and the height d is between 2 mm and 3 mm. Optionally, d is 2.4 mm. The appropriate height distance d can affect the size of the vortex system generated in the channel 11 corresponding to the guide surface 32 and the channel 11 away from the guide surface 32, thereby affecting the intake flow of each channel 11, so that the intake flow of each channel 11 is reasonably distributed, avoiding the problem that the performance of the engine will be seriously affected due to excessive use of cold air.

[0032] like Figure 5 As shown, in one embodiment, there are three channels 11 and they are respectively connected to the high-pressure reflux chamber 2. It should be noted that the three channels 11 are independent of each other, and the guide platform 3 is located near two of the channels 11, so that the vortex system near the two channels 11 can be reduced, so that the gas flow in the channel 11 is increased, and the vortex system of the channel 11 away from the guide platform 3 is increased, so that the gas flow in the channel 11 here is reduced, and the gas flow of each channel 11 is reasonably distributed.

[0033] like Figure 2As shown, in one embodiment, the high-pressure reflux chamber 2 includes a first cavity 21, a second cavity 22, a third cavity 23 and a fourth cavity 24, two adjacent channels 11 are respectively connected to the second cavity 22, and the other channel 11 is connected to the third cavity 23, the first cavity 21 and the second cavity 22 are connected, and the third cavity 23 and the fourth cavity 24 are connected. It should be noted that a large vortex is easily formed at the channel 11 where there is no guide platform 3, the cold air flow rate of the channel 11 is reduced, and the gas entering the first cavity 21 and the second cavity 22 is reduced, while there is no vortex system in the channel 11 far away from the air inlet, the flow rate is relatively fast, and more cold air enters the third cavity 23 and the fourth cavity 24, resulting in a relatively small amount of cold air entering the first cavity 21 and the second cavity 22, so that the temperature of the leading edge of the blade and the blade basin (near the leading edge) is too high, while the temperature near the middle section of the blade is too low, the temperature gradient is large, the local stress is relatively large, and the service life of the turbine rotor blade is reduced. The existence of the guide platform 3 causes the large vortex originally near the guide platform 3 to be broken up, and only a small vortex is formed at the inlet of the channel 11 near the guide platform 3. The cold air flow rate at the inlet of the channel 11 is increased, and the cold air flow rate flowing into the inner cavity of the blade through the channel 11 is increased, so as to provide more cooling gas for the leading edge and blade basin (near the leading edge) of the blade which are severely impacted by the high-temperature and high-pressure gas. At the same time, a large vortex is formed in the channel 11 far away from the air inlet, and the cold air flow rate at the channel 11 is reduced, and the cold air flow entering the channel 11 is reduced, thereby reducing the cooling air supply to the middle section of the blade, thereby affecting the cold air flow distribution of the three cold air channels 11.

[0034] In one embodiment, a plurality of air film holes 211 are provided on one side wall of the first cavity 21, and a plurality of air vents 212 are provided on the other side wall of the first cavity 21 to connect the first cavity 21 with the second cavity 22. The air film holes 211 and the air holes provide more cooling gas to the leading edge of the blade and the blade basin (near the leading edge).

[0035] In one embodiment, the second cavity 22 is an L-shaped structure and is provided with a plurality of exhaust holes 221 at its end, and a plurality of eccentric slits 241 are provided at the outlet end of the fourth cavity 24. The exhaust holes 221 can reduce the temperature near the middle section of the blade, thereby reducing the service life of the turbine rotor blade. The eccentric slits 241 can evenly discharge the gas flowing out of the cavity, thereby increasing the service life of the turbine rotor blade.

[0036] like Figure 3As shown, when the engine is working, the turbine rotor blades rotate at high speed, and a vortex system is generated at the tail of the air inlet channel 11 at the bottom of the blade tenon 1. Compared with the rotor blade without the guide platform 3, due to the existence of the guide platform 3 of the present invention, the large vortex originally near the guide platform 3 is broken up, so that the large vortex originally near the guide platform 3 is weakened, and only a small vortex is formed there, the energy consumption of the vortex system is reduced, and the cold air flow velocity near the cold air channels Ⅰ and Ⅱ is increased. The air inlet angle α is located on the air inlet surface 31 of the guide platform 3, which has the function of guiding the cooling air flow into channels Ⅰ and Ⅱ. Through the guiding effect of the guide angle β, more cooling air flows into the blade cavity through channels Ⅰ and Ⅱ. At the same time, a large vortex is formed near channel Ⅲ behind the guide platform 3, the cold air flow velocity at the entrance of channel Ⅲ is reduced, and the cold air flow entering channel Ⅲ is reduced, which in turn affects the cold air flow distribution of the three cold air channels of channels Ⅰ, Ⅱ, and Ⅲ. After the drag reduction and vortex reduction of the flow guide platform 3, the flow rate of cold air entering channel I increases, the flow rate accelerates, and the heat exchange capacity of the cold air inside the second cavity 22 is strengthened, which can effectively reduce the surface temperature of the blade near the second cavity 22. The cold air inside the second cavity 22 flows radially outward, enters the first cavity 21 through the vent hole 212 on the baffle of the first cavity 21, performs impact cooling on the leading edge, and is discharged from the leading edge air film hole 211. The surface temperature of the leading edge blade is significantly reduced. The leading edge of the blade belongs to the high temperature zone. Through the drag reduction and vortex reduction effect of the flow guide platform 3, the cooling gas flow rate and heat exchange capacity of the leading edge high temperature zone are improved, and precise thermal protection is implemented for the leading edge and blade basin (near the leading edge) of the blade that are severely impacted by the high temperature and high pressure gas bureau, which helps to reduce the maximum temperature of the entire blade and the average temperature of the blade, reduce the temperature gradient of the blade, and increase the service life of the blade. A guide platform 3 for guiding flow is provided at the bottom of the blade tenon 1. A large vortex is formed at the rear end surface of the guide platform 3, i.e., at the entrance of channel III. The velocity of the cold air flow at the entrance of channel III is reduced, and the flow of cold air entering channel III is reduced, so that the cooling gas used for the third cavity 23 and the fourth cavity 24 is reduced, and the temperature near the third cavity 23 in the middle section of the blade increases. The temperature in the middle section of the blade belongs to the low temperature zone relative to the entire blade. The increase in the temperature in the low temperature zone helps to reduce the temperature gradient in the middle section of the blade and increase the service life of the blade. A guide platform 3 is added to the bottom of the turbine rotor blade, and the flow of cold air entering the first cavity 21 and the second cavity 22 is increased, and the flow velocity is accelerated. Precise thermal protection is implemented for the leading edge and blade basin (near the leading edge) of the blade that are severely impacted by the high-temperature and high-pressure gas. The maximum surface temperature of the turbine rotor blade is reduced by 30 to 55K, the average surface temperature of the blade is reduced by 15 to 25K, and the surface temperature of the low temperature zone in the middle section of the blade is increased by 10 to 20K, which can effectively reduce the surface temperature gradient of the blade and increase the service life of the blade. In addition, if Figure 7 As shown, it can be seen from the figure that the vortex distribution of each channel 11 is relatively uniform, so that the air intake of each channel 11 is relatively reasonable. Compared with the present invention, in the prior art, the vortex sizes in the figure are different, which makes the air intake distribution of the channel 11 not uniform enough.

[0037] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A flow guide device for a turbine rotor blade tenon, characterized in that: include: A blade tenon (1) and a high-pressure return chamber (2) connected to the blade tenon (1); a plurality of channels (11) are provided on a plane of the blade tenon (1); each of the channels (11) is respectively connected to the high-pressure return chamber (2); a guide platform (3) is provided on a plane of the blade tenon (1); the guide platform (3) is close to the corresponding channel (11); an air intake surface (31) and a guide surface (32) are respectively provided on two adjacent side surfaces of the guide platform (3); the air intake surface (31) is close to the air intake inlet of the blade tenon (1); and the guide surface (32) is located above the corresponding channel (11).

2. The flow guide device for the tenon of a turbine rotor blade according to claim 1, characterized in that: The air inlet surface (31) is projected onto the X direction of a reference point to form an angle α, the angle α is between 8° and 15°, and the reference point is the center point of the blade.

3. The flow guide device for the tenon of a turbine rotor blade according to claim 1, characterized in that: The axial direction of the guide surface (32) forms an angle β with the Y direction of the reference point, and the angle β is 35° to 50°.

4. The flow guide device for the tenon of a turbine rotor blade according to claim 1, characterized in that: The distance between the dividing line (34) on the guide surface (32) and the reference point of the blade tenon (1) is a, and the distance a is between 1.5 mm and 2 mm.

5. The flow guide device for the tenon of a turbine rotor blade according to claim 1, characterized in that: The distance between the end of the air inlet surface (31) and one side edge of the blade tenon (1) is c, and the distance c is between 1.5 mm and 2.5 mm.

6. The flow guide device for the tenon of a turbine rotor blade according to claim 1, characterized in that: The height of the guide platform (3) is d, and the height d is between 2 mm and 3 mm.

7. The flow guide device for the tenon of a turbine rotor blade according to claim 1, characterized in that: There are three channels (11) which are respectively connected to the high-pressure reflux chamber (2).

8. The flow guide device for the tenon of a turbine rotor blade according to claim 1, characterized in that: The high-pressure reflux chamber (2) comprises a first chamber (21), a second chamber (22), a third chamber (23) and a fourth chamber (24); two adjacent channels (11) are respectively connected to the second chamber (22); another channel (11) is connected to the third chamber (23); the first chamber (21) is connected to the second chamber (22); and the third chamber (23) is connected to the fourth chamber (24).

9. The flow guide device for the tenon of a turbine rotor blade according to claim 8, characterized in that: A plurality of air film holes (211) are provided on one side wall of the first cavity (21), and a plurality of vent holes (212) are provided on the other side wall of the first cavity (21) to connect the first cavity (21) and the second cavity (22).

10. The flow guide device for the tenon of a turbine rotor blade according to claim 8, characterized in that: The second cavity (22) is an L-shaped structure and is provided with a plurality of exhaust holes (221) at its end, and the outlet end of the fourth cavity (24) is provided with a plurality of deflected slits (241).

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