A turbine variable guide vane based on pneumatic adjustment and a control method

Abstract

This invention relates to the field of aero-engine technology and discloses an adjustable turbine guide vane based on aerodynamic adjustment and its control method. A hollow rotating shaft with an exhaust slot is provided on the blade body of the adjustable turbine guide vane. The hollow rotating shaft is connected to an air intake pipe through a bushing. The hollow rotating shaft is provided with a circular air intake window that communicates with the air intake pipe. When the engine turbine guide vane performs aerodynamic adjustment in response to different operating conditions, the position of the exhaust slot is changed by rotating the hollow rotating shaft, thereby adjusting the direction of the jet ejected from the exhaust slot for aerodynamic adjustment. At the same time, the opening of the circular air intake window is adjusted by rotating the hollow rotating shaft, thereby adjusting the flow rate of the jet for aerodynamic adjustment.

Description

Technical Field

[0001] This invention relates to the field of aero-engine technology, and discloses a turbine adjustable guide vane based on aerodynamic regulation and its control method. Background Technology

[0002] Adaptive variable cycle characteristics are one of the important development trends of next-generation engines. The throat area of ​​the turbine guide vane is a crucial parameter affecting the operation of engines used in aircraft, ships, and tanks. Looking at future power technology development trends, adjustable turbine guide vane area allows engines to operate over a wider bypass ratio range, while the compressor can maintain a fixed matching point to achieve high efficiency. This is a crucial means to simultaneously achieve high thrust in supersonic flight and low fuel consumption in subsonic flight, and represents an important direction for the future development of aero-engines.

[0003] Traditional variable geometry blade technology typically employs mechanical adjustment, using an additional adjustment mechanism on the outside of the duct, which drives the guide vanes to rotate via a hollow shaft. This approach is suitable for fine-tuning of a wide range of flow rates and has been successfully applied to variable geometry components such as fans, compressors, low-pressure turbines, and power turbines. However, mechanical adjustment requires additional adjustment mechanisms within the engine, increasing engine weight; gaps and sealing issues exist between mechanical structures; the presence of guide vane tip clearance significantly increases turbine efficiency losses; and mechanically adjustable guide vanes, whether using a whole-blade rotation scheme, a split design, or a partially adjustable blade scheme, all significantly impact the integrity of the blade cooling flow path, posing challenges to blade cooling design.

[0004] To address the inherent problems of mechanical control, an aerodynamic control technique has been proposed abroad. This technique involves actively injecting a controllable jet from the blade surface into the flow channel, altering the throat area and achieving aerodynamic throat control. The main advantage of this approach is that it avoids the impact of tip clearance caused by guide vane rotation on turbine aerodynamic losses, and its structure is relatively simple. Currently, related research is still in the conceptual demonstration stage. One of the main challenges of this technology lies in how to solve the problems of controlling the direction and flow rate of the jet from the blade surface under different engine operating conditions. Summary of the Invention

[0005] The purpose of this invention is to provide a turbine adjustable guide vane based on aerodynamic adjustment and a control method, so that the turbine guide vane of the engine can achieve aerodynamic adjustment of jet direction and jet flow rate when aerodynamic adjustment is performed to cope with different operating conditions.

[0006] To achieve the above-mentioned technical effects, the technical solution adopted by the present invention is as follows:

[0007] A turbine-adjustable guide vane based on aerodynamic regulation, comprising:

[0008] The blade has an axial hole that intersects with the suction surface of the blade and forms a jet window on the suction surface that communicates with the axial hole, and the jet window is located in the throat region corresponding to the suction surface.

[0009] A hollow rotating shaft is installed in the shaft hole; one end of the hollow rotating shaft is connected to an air intake pipe through a bushing; the hollow rotating shaft is provided with a circular air intake window communicating with the air intake pipe; the hollow rotating shaft is provided with an exhaust slit along the axial direction, and the exhaust slit faces the jet window.

[0010] A drive mechanism is provided to drive the hollow shaft to rotate at a preset deflection angle, thereby changing the angle of the jet ejected from the exhaust slit and simultaneously changing the opening of the circular air intake window relative to the air intake pipe opening.

[0011] Furthermore, the hollow rotating shaft is located on the outer wall surface inside the jet window, which is smoothly connected to the suction surface.

[0012] Furthermore, an upper edge plate and a lower edge plate are respectively provided on both sides of the blade, and the shaft hole passes through the upper edge plate and the lower edge plate.

[0013] Furthermore, one end of the hollow rotating shaft is located on one side of the upper edge plate, and the other end of the hollow rotating shaft is rotatably connected to the lower edge plate.

[0014] Furthermore, the blade body is provided with a first chamber, a second chamber and a third chamber, the lower edge plate is provided with a first air inlet communicating with the first chamber, and the upper edge plate is provided with a second air inlet and a third air inlet communicating with the second chamber and the third chamber.

[0015] Furthermore, the length of the exhaust slit is the same as the length of the jet window.

[0016] A method for controlling turbine adjustable guide vanes based on aerodynamic regulation, comprising:

[0017] Determine that the opening of the circular air intake window is 100% when the engine is under a preset reference operating condition, and obtain the air intake flow rate of the circular air intake window under the preset reference operating condition;

[0018] A pneumatic adjustment intake flow analysis model based on the deflection angle of the hollow shaft is constructed. The radius of the circular intake window, the intake flow of the circular intake window when the engine is under a preset reference condition, and the intake flow required by the circular intake window when the engine is under a target condition are analyzed using the pneumatic adjustment intake flow analysis model to obtain the deflection angle of the hollow shaft when the engine changes from the preset reference condition to the target condition.

[0019] Based on the deflection angle of the hollow shaft when the engine changes from a preset reference operating condition to a target operating condition, the drive mechanism drives the hollow shaft to rotate, thereby adjusting the angle of the exhaust jet and the intake flow rate of the circular intake window.

[0020] Furthermore, the aerodynamic adjustment intake flow analysis model based on the hollow shaft deflection angle is constructed as follows:

[0021] ;

[0022] in, The required airflow rate for the circular air intake window under the target operating conditions. This is the intake flow rate of the circular air intake window under preset reference operating conditions. The radius of the circular air intake window. It is an inverse cosine function. This refers to the deflection angle of the hollow shaft when the engine changes from the preset reference operating condition to the target operating condition.

[0023] Compared with the prior art, the beneficial effects of this invention are:

[0024] This invention features a hollow shaft with an exhaust slit on the blade of an adjustable turbine guide vane. The hollow shaft is connected to an intake pipe via a bushing. The hollow shaft has a circular intake window that communicates with the intake pipe. When the turbine guide vane performs aerodynamic adjustments for different operating conditions, the position of the exhaust slit is changed by rotating the hollow shaft, thereby adjusting the direction of the jet ejected from the exhaust slit for aerodynamic adjustment. At the same time, the opening of the circular intake window is adjusted by rotating the hollow shaft, thereby adjusting the flow rate of the jet for aerodynamic adjustment. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the turbine adjustable guide vane structure based on aerodynamic adjustment in the embodiment.

[0026] Figure 2 for Figure 1 AA section view in the middle;

[0027] Figure 3 This is a first isometric view of the turbine adjustable guide vane based on aerodynamic adjustment in the embodiment.

[0028] Figure 4 This is a second isometric view of the turbine adjustable guide vane based on aerodynamic adjustment in the embodiment.

[0029] Figure 5 This is a schematic diagram of the hollow rotating shaft, bushing, and intake pipe in the embodiment.

[0030] Figure 6 for Figure 5 BB section view in the middle;

[0031] Figure 7 This is a schematic diagram of the aerodynamic adjustment of the turbine adjustable guide vanes under high engine load conditions.

[0032] Figure 8 This is a schematic diagram of the aerodynamic adjustment of the turbine adjustable guide vanes under low engine load conditions.

[0033] Figure 9 This is a schematic diagram of the air intake of the hollow shaft under low-load engine conditions.

[0034] Figure 10 This is a schematic diagram of the air intake of the hollow shaft under high-load engine conditions.

[0035] Figure 11 This is a cross-sectional view of the hollow shaft, bushing, and intake manifold under high-load engine conditions.

[0036] Figure 12 This is a flowchart of the turbine adjustable guide vane control method based on aerodynamic adjustment in the embodiment.

[0037] Among them, 11-blade body, 12-upper edge plate, 13-lower edge plate, 14-jet window, 15-first chamber, 16-second chamber, 17-third chamber, 2-hollow rotating shaft, 21-circular air inlet window, 22-exhaust slit, 3-shaft sleeve, 4-air inlet pipe. Detailed Implementation

[0038] The present invention will now be described in further detail with reference to the embodiments and accompanying drawings. However, this should not be construed as limiting the scope of the above-described subject matter of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0039] Example

[0040] See Figures 1 to 11 A turbine-adjustable guide vane based on aerodynamic regulation, comprising:

[0041] The blade 11 has an upper edge plate 12 and a lower edge plate 13 on both sides. The blade 11 has a shaft hole that passes through the upper edge plate 12 and the lower edge plate 13. The shaft hole intersects with the suction surface of the blade 11 and forms a jet window 14 that communicates with the shaft hole on the suction surface. The jet window 14 is located in the throat area corresponding to the suction surface.

[0042] A hollow shaft 2 is installed within the shaft hole. The M-end of the hollow shaft 2 extends to the outside of the upper edge plate 12 and is inserted into the turbine main flow channel. It is then connected to an intake pipe 4 via a bushing 3. The N-end of the hollow shaft 2 is rotatably connected to the lower edge plate 13. The hollow shaft 2 has a circular intake window 21 communicating with the intake pipe 4. An exhaust slit 22 is axially arranged on the hollow shaft 2, facing the jet window 14. The length of the exhaust slit 22 is the same as the length of the jet window 14. The airflow in the turbine main flow channel flows into the circular intake window 21 after passing through the intake pipe 4, and then into the hollow shaft 2. It is then ejected from the exhaust slit 22 to form a jet. The jet enters the throat region through the jet window 14, achieving aerodynamic adjustment of the throat area between two adjacent adjustable turbine guide vanes, thereby achieving turbine flow regulation. It should be noted that a base can be fixed to the lower end of the shaft hole. This base is flush with the lower edge plate 13. The N end of the hollow shaft 2 is inserted into the base to ensure that the hollow shaft 2 can rotate normally. The gap between the hollow shaft 2 and the base must meet the requirements of aerodynamic adjustment. The turbine main flow channel refers to the flow channel where the turbine adjustable guide vanes are located.

[0043] The drive mechanism drives the hollow shaft 2 to rotate at a preset deflection angle, thereby changing the angle of the jet ejected from the exhaust slit 22 and simultaneously changing the opening of the circular air intake window 21 relative to the air intake pipe 4. It should be noted that the drive mechanism can be a motor, a combination of a motor and a reduction gear assembly, or other drive mechanisms.

[0044] It should be noted that, as Figure 6 and Figure 9 As shown, under low engine load conditions and when the turbine inlet temperature is low, the circular air intake window 21 of the hollow shaft 2 faces the inlet of the intake pipe 4, and the opening of the circular air intake window 21 relative to the inlet of the intake pipe 4 is 100%. The cooling air in the intake pipe 4 flows into the hollow shaft 2 through the circular air intake window 21, and at this time, the intake flow rate of the circular air intake window 21 is the maximum. Figure 10 and Figure 11 As shown, under high engine load conditions, the turbine inlet temperature is high. When the hollow shaft 2 deflects at a certain angle, the circular air intake window 21 is not directly aligned with the intake pipe 4 opening, and a portion of the circular air intake window 21 is blocked by the bushing 3. At this time, the opening of the circular air intake window 21 relative to the intake pipe 4 opening is less than 100%, and the intake flow rate of the circular air intake window 21 decreases. This invention utilizes the rotation of the hollow shaft 2, combined with the bushing 3, to control the opening of the circular air intake window 21, thereby achieving active control of the jet flow rate under different engine operating conditions.

[0045] It should be noted that the hollow shaft 2 is a hollow column with both ends closed, the circular air inlet 21 is the air intake structure of the hollow shaft 2, and the exhaust slit 22 is the air outlet structure of the hollow shaft 2. In this invention, the hollow shaft 2 and the bushing 3, as well as other places that require sealing, are all sealed using existing dynamic or static sealing elements or methods.

[0046] In some embodiments, the outer wall surface of the hollow shaft 2 located within the jet window 14 is smoothly connected to the suction surface. The outer side of the hollow shaft 2 portion of the present invention, together with the blade 11, forms a smooth aerodynamic shape on the blade suction surface to reduce blade shape loss.

[0047] In some embodiments, such as Figure 2 and Figure 4 As shown, the blade 11 has a first chamber 15, a second chamber 16, and a third chamber 17. The lower edge plate 13 has a first air inlet connecting to the first chamber 15, and the upper edge plate 12 has a second air inlet and a third air inlet connecting the second chamber 16 and the third chamber 17. The blade 11 of the present invention adopts a three-chamber structure. The first chamber 15 is inlet through the lower edge plate 13, and the second chamber 16 and the third chamber 17 are inlet through the upper edge plate 12. Without affecting the continuity of the blade pressure surface, the blade 11 and the hollow rotating shaft 2 together form the aerodynamic shape of the suction surface, ensuring the continuity and smoothness of the blade suction surface and reducing blade shape loss.

[0048] The blade 11 may have the cooling forms of conventional blades, including but not limited to air film holes, turbulence ribs, turbulence columns, tail slits, serpentine channels, impact bushings, plate cooling, double-wall cooling structures, etc., and the cooling flow path of the blade 11 and the air intake flow path of the hollow rotating shaft 2 are independent of each other.

[0049] The turbine adjustable guide vane based on aerodynamic adjustment of the present invention can adjust the jet angle and jet flow rate by rotating the hollow shaft 2 when aerodynamic adjustment is performed to cope with different working conditions. That is, a large flow vertical jet is achieved when the engine is under low load, and a small flow wall-mounted jet is achieved when the engine is under high load.

[0050] Specifically, the working process of the turbine adjustable guide vane based on aerodynamic regulation is divided into two states: under high engine load conditions, the drive mechanism drives the hollow shaft 2 to rotate to the position shown in the figure. Figure 7 As shown, the effective area of ​​the circular air intake window 21 is partially blocked, resulting in a smaller intake flow. Simultaneously, the position of the exhaust slit 22 directs the jet angle downstream of the blades, causing the jet to adhere to the wall surface and form a film of air, aiding in blade cooling. At this time, the turbine mains throat area is A1. Under low engine load conditions, the drive mechanism drives the hollow shaft 2 to rotate as shown... Figure 8As shown, the circular air intake window 21 is fully open, achieving a larger air intake flow. At the same time, the position of the exhaust slit 22 makes the jet angle perpendicular to the incoming flow. At this time, the throat area of ​​the turbine main flow channel is A2, and A2 < A1, which produces the effect of blocking the blade throat area, realizing turbine flow regulation under low load conditions.

[0051] This invention achieves low-flow wall-following jet under high engine load conditions and high-flow vertical jet under low engine load conditions through the aforementioned two working modes, thereby realizing turbine flow regulation under different engine operating conditions. Compared with conventional adjustable guide vanes, the aerodynamically adjustable guide vane retains the structural integrity of the blade body 11 to the greatest extent, allowing the blade body 11 and the upper and lower edge plates to be integrated into a single design, avoiding the flow loss caused by the edge plate gap due to blade rotation in conventional adjustable guide vanes. The hollow rotating shaft 2 and the blade body 11 are smoothly continuous on the blade suction surface, ensuring the aerodynamic performance of the blade. The hollow rotating shaft 2 occupies a small area compared to the blade profile area, which is beneficial to increasing the degree of freedom in the design of the cooling structure of the blade body 11.

[0052] The high-load and low-load operating conditions of the engine described in this invention correspond to the high-speed and low-speed flight conditions of an aircraft, respectively. In the low-load condition, the turbine inlet temperature of the variable-cycle engine is relatively low, resulting in a smaller cooling airflow for the turbine adjustable guide vanes. A portion of the cooling air used for the turbine adjustable guide vanes is introduced into the hollow rotating shaft 2, forming a jet that enters the throat of the main flow channel between the turbine adjustable guide vanes through the exhaust slot 22. This reduces the throat area of ​​the main flow channel, decreases the flow rate, and achieves aerodynamic regulation of the main flow rate. When the variable cycle engine changes from a low-load condition to a high-load condition, the turbine inlet temperature rises, requiring more cooling air to be allocated for cooling the turbine adjustable guide vanes. At the same time, it is necessary to increase the throat area of ​​the main flow channel and increase the flow rate of the main flow channel. Therefore, this invention reduces the opening of the circular air intake window 21 on the hollow shaft 2 by deflecting the hollow shaft 2 by deflecting it at a preset deflection angle, thereby reducing the air intake flow rate entering the hollow shaft 2. At the same time, the position of the exhaust slit 22 is changed to adjust the jet angle, thereby increasing the throat area of ​​the main flow channel and increasing the flow rate of the main flow channel, thus achieving aerodynamic regulation of the flow rate of the main flow channel.

[0053] Based on the same inventive concept, such as Figure 12 As shown, this embodiment also provides a turbine adjustable guide vane control method based on aerodynamic regulation, used to control the turbine adjustable guide vane, including:

[0054] Step 1: Determine that the opening degree of the circular air intake window 21 is 100% when the engine is under a preset reference operating condition, and obtain the intake air flow rate of the circular air intake window 21 under the preset reference operating condition. The preset reference operating condition refers to the engine's low-load operating condition, under which the intake air flow rate of the circular air intake window 21 is... This can be obtained through simulation. The opening of the circular air intake window 21 relative to the opening of the air intake pipe 4 is as follows: Figures 9 to 11 As shown.

[0055] Step 2: Construct an aerodynamic intake flow analysis model based on the deflection angle of the hollow shaft 2; use the aerodynamic intake flow analysis model to analyze the radius of the circular intake window 21. The intake airflow of the circular air intake window 21 when the engine is operating under preset reference conditions. The required intake airflow of the circular air intake window 21 when the engine is operating under target conditions. The deflection angle of the hollow shaft 2 is obtained when the engine changes from a preset reference operating condition to a target operating condition. ;

[0056] Specifically, firstly, the aerodynamic adjustment intake flow analysis model based on the deflection angle of the hollow shaft 2 is constructed as follows:

[0057] ;

[0058] in: The required intake flow rate for the circular air intake window 21 under the target operating condition can be obtained by simulating the engine under the target operating condition. ; The intake flow rate of the circular intake window 21 is preset to the reference operating condition; The radius of the circular air intake window 21; It is the inverse cosine function; The deflection angle of the hollow shaft 2 when the engine changes from the preset reference condition to the target condition.

[0059] Then, when the engine changes from a preset reference condition to a target condition, the radius of the circular air intake window 21 is used as a reference. The intake airflow of the circular intake window 21 when the engine is in a preset reference operating condition. The required intake airflow of the circular air intake window 21 when the engine is operating under target conditions. The deflection angle of the hollow shaft 2 when the engine changes from a preset reference operating condition to a target operating condition is obtained by using an aerodynamic intake flow analysis model. .

[0060] It should be noted that the target operating condition refers to the engine's high-load operating condition. Under one type of high-load operating condition, the opening of the circular air intake window 21 relative to the inlet of the air intake pipe 4 is as follows: Figure 10 As shown.

[0061] It should be noted that, taking the position of the circular intake window 21 or exhaust slit 22 on the hollow shaft 2 under the preset reference operating condition as the reference position, and the position of the circular intake window 21 or exhaust slit 22 on the hollow shaft 2 under the target operating condition as the target position, the rotation angle of the circular intake window 21 or exhaust slit 22 on the hollow shaft 2 from the reference position to the target position is the deflection angle of the hollow shaft. .

[0062] Step 3: Based on the deflection angle of the hollow shaft 2 when changing from the preset reference working condition to the target working condition. The drive mechanism drives the hollow shaft 2 to rotate, thereby adjusting the angle of the jet ejected from the exhaust slit 22 and adjusting the air intake flow rate of the circular air intake window 21.

[0063] The present invention provides a hollow rotating shaft 2 with an exhaust slit 22 on the blade body 11 of the turbine adjustable guide vane. The hollow rotating shaft 2 is connected to an intake pipe 4 through a bushing 3. The hollow rotating shaft 2 is provided with a circular intake window 21 that communicates with the intake pipe 4. When the engine turbine guide vane performs aerodynamic adjustment in response to different operating conditions, the position of the exhaust slit 22 is changed by rotating the hollow rotating shaft 2, thereby adjusting the direction of the jet ejected from the exhaust slit 22 for aerodynamic adjustment. At the same time, the opening of the circular intake window 21 relative to the inlet of the intake pipe 4 is adjusted by rotating the hollow rotating shaft 2, thereby adjusting the flow rate of the jet for aerodynamic adjustment.

[0064] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A turbine variable guide vane based on pneumatic adjustment, characterized by, include: The blade (11) is provided with a shaft hole, the shaft hole intersects with the suction surface of the blade (11), and a jet window (14) communicating with the shaft hole is formed on the suction surface, and the jet window (14) is located in the throat area corresponding to the suction surface; A hollow rotating shaft (2) is installed in the shaft hole; the inner cavity of the hollow rotating shaft (2) is connected to an air inlet pipe (4) through a bushing (3); the hollow rotating shaft (2) is provided with a circular air inlet window (21) communicating with the air inlet pipe (4); the hollow rotating shaft (2) is provided with an exhaust slit (22) along the axial direction, and the exhaust slit (22) faces the jet window (14); the outer wall surface of the hollow rotating shaft (2) located inside the jet window (14) is smoothly connected to the suction surface; The drive mechanism is used to drive the hollow shaft (2) to rotate at a preset deflection angle, so as to change the angle of the jet ejected from the exhaust slit (22) and at the same time change the opening of the circular air intake window (21).

2. The pneumatic adjustment based turbine variable guide vane of claim 1, wherein, The blade (11) is provided with an upper edge plate (12) and a lower edge plate (13) on both sides, and the shaft hole passes through the upper edge plate (12) and the lower edge plate (13).

3. The pneumatic adjustment based turbine variable guide vane of claim 2, wherein, One end of the hollow rotating shaft (2) is located on one side of the upper edge plate (12), and the other end of the hollow rotating shaft (2) is rotatably connected to the lower edge plate (13).

4. The pneumatic adjustment based turbine variable guide vane of claim 3, wherein, The blade (11) is provided with a first chamber (15), a second chamber (16) and a third chamber (17). The lower edge plate (13) is provided with a first air inlet that connects to the first chamber (15). The upper edge plate (12) is provided with a second air inlet and a third air inlet that connect the second chamber (16) and the third chamber (17).

5. The pneumatic adjustment based turbine variable guide vane of claim 1, wherein, The length of the exhaust slit (22) is the same as the length of the jet window (14).

6. A method of controlling a turbine variable stator vane based on pneumatic adjustment, for controlling the turbine variable stator vane according to any one of claims 1-5, characterized in that, include: The opening degree of the circular air intake window (21) of the engine is determined to be 100% under the preset reference operating conditions, and the air intake flow rate of the circular air intake window (21) under the preset reference operating conditions is obtained. A pneumatic adjustment intake flow analysis model based on the deflection angle of the hollow shaft (2) is constructed. The radius of the circular intake window (21), the intake flow of the circular intake window (21) under the preset reference operating condition, and the required intake flow of the circular intake window (21) under the target operating condition are analyzed using this model to obtain the deflection angle of the hollow shaft (2) when the engine changes from the preset reference operating condition to the target operating condition. The pneumatic adjustment intake flow analysis model based on the deflection angle of the hollow shaft (2) is constructed as follows: ； wherein, Qtarget is the required intake flow rate of the circular intake window (21) for the target operating condition, Qreference is the intake flow rate of the circular intake window (21) for the preset reference operating condition, R is the radius of the circular intake window (21), arccos is the inverse cosine function, is the deflection angle of the hollow rotating shaft (2) when the engine changes from the preset reference operating condition to the target operating condition. According to the deflection angle of the hollow shaft (2) when the engine changes from the preset reference condition to the target condition, the drive mechanism drives the hollow shaft (2) to rotate, so as to adjust the angle of the jet ejected from the exhaust slit (22) and the intake flow of the circular air intake window (21).

Images