Turbine adjustable guide vane with telescopic trailing edge

Abstract

The invention relates to a tail edge telescopic type turbine adjustable guide vane, and relates to the technical field of aero-engines. Comprising a hub, a casing and guide vane blades, the guide vane blade is divided into a guide vane main body and a tail edge telescopic section; the front end of the tail edge telescopic section is inserted into the guide vane main body and is in sliding connection with the guide vane main body; a hub guide groove is formed in the hub, a machine brake guide groove is formed in the machine brake, the blade root end of the trailing edge telescopic section is arranged in the hub guide groove in a sliding mode, and the blade tip end of the trailing edge telescopic section is arranged in the machine brake guide groove in a sliding mode. Adjustment of the throat area of the turbine guide vane is achieved through stretching and retracting of the tail edge stretching and retracting section, meanwhile, leakage flow of an end area is avoided, and the pneumatic loss is reduced while the working condition of a turbine is adjustable.

Description

Technical Field

[0001] The invention relates to the technical field of aeroengines, in particular to a trailing edge telescopic turbine adjustable guide vane. Background Art

[0002] The requirements of aircraft such as high thrust-to-weight ratio, low fuel consumption, and long endurance require that aircraft engines have large thrust and high efficiency when the aircraft is flying at subsonic and supersonic speeds. This requires that the turbine components of aircraft engines have a certain range of operating condition adjustment capabilities, and that the above requirements are met by adjusting the power distribution and bypass ratio required by the engine. Turbine operating condition adjustment is generally achieved by driving the turbine guide vanes to rotate through an actuator and changing the guide vane installation angle. Although this method is easy to implement, since radial clearance needs to be reserved between the hub and the casing when rotating the guide vanes, the leakage loss generated has a significant impact on the aerodynamic performance of the turbine, and the benefits of the turbine operating condition adjustment scheme are therefore reduced.

[0003] Therefore, how to provide a trailing edge retractable turbine adjustable guide vane that is convenient for adjusting the turbine operating conditions has become a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0004] In order to solve at least one technical problem in the background technology, the present invention provides a trailing edge telescopic turbine adjustable guide vane, which utilizes the telescopic section of the trailing edge to adjust the throat area of ​​the turbine guide vane, while avoiding the generation of end zone leakage flow, thereby reducing aerodynamic losses while achieving adjustable turbine operating conditions.

[0005] To achieve the above-mentioned purpose, the present invention provides a trailing edge telescopic turbine adjustable guide vane, comprising: a hub, a casing and a guide vane blade; the guide vane blade is divided into two parts: a guide vane body and a trailing edge telescopic section; the front end of the trailing edge telescopic section is inserted into the guide vane body and is slidably connected to the guide vane body; a hub guide groove is provided on the hub, and an engine gate guide groove is provided on the engine gate, the root end of the trailing edge telescopic section is slidably set in the hub guide groove, and the tip end of the trailing edge telescopic section is slidably set in the engine gate guide groove.

[0006] Furthermore, a sealing plate and a driving handle are fixed to the tip of the trailing edge telescopic section blade.

[0007] Furthermore, an actuator is arranged on the outer ring of the casing, and a driving arm of the actuator is connected to a driving handle to drive the trailing edge telescopic section to move along the casing guide groove.

[0008] Furthermore, a stop is provided at the front end of the trailing edge telescopic section to limit the longest extension position of the trailing edge telescopic section.

[0009] Furthermore, ribs are provided on both the pressure surface side and the suction surface side of the guide vane body to limit the longest retracted position of the trailing edge telescopic section.

[0010] Furthermore, the chord length of the trailing edge telescopic section does not exceed 30% of the total chord length of the guide vane blade.

[0011] Furthermore, the channel between the two guide vane blades is of a contraction type, and the flow direction position of the trailing edge of the trailing edge telescopic section is the turbine throat. When the trailing edge telescopic section is retracted into the guide vane body, the turbine throat moves upstream accordingly, and the throat area gradually increases; when the trailing edge telescopic section is completely retracted into the guide vane body, the turbine throat area increases to a maximum value.

[0012] The beneficial effects of the present invention are:

[0013] The trailing edge telescopic turbine adjustable guide vane of the present invention utilizes the upstream and downstream movement of the trailing edge telescopic section to change the area of ​​the turbine throat, which can realize the turbine variable operating condition adjustment capability and meet the overall requirements of the engine. During the operating condition adjustment process, the trailing edge telescopic turbine does not generate leakage flow, and can maintain the flow structure of the guide vane end area without significant changes, without significantly increasing the additional aerodynamic loss of the guide vane end area. The present invention has a high engineering application value in controlling leakage losses of turbine adjustable guide vanes, and has a positive impact on improving the aerodynamic performance of the engine. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is the meridional flow diagram of the turbine guide vane of the present invention (minimum throat area state);

[0015] Figure 2 This is the meridional flow diagram of the turbine guide vane of the present invention (maximum throat area state);

[0016] Figure 3 This is the state diagram of the minimum throat area of ​​the S1 section of the present invention;

[0017] Figure 4 This is the state diagram of the maximum throat area of ​​the S1 section of the present invention.

[0018] Among them, 1-guide vane body, 2-trailing edge telescopic section, 3-hub, 4-casing, 5-hub guide groove, 6-casing guide groove, 7-sealing plate, 8-driving handle. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only 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.

[0020] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0021] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0022] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.

[0023] In addition, the terms "installed", "set", "provided with", "connected", "connected", and "socketed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0024] Based on the principle that turbine operating condition regulation is achieved by changing the throat area of ​​the turbine guide vane, the present invention provides a trailing edge retractable turbine adjustable guide vane, that is, the guide vane is divided into two parts with a certain point downstream of the guide vane as the boundary, and the downstream part can be retracted and retracted in the upstream guide vane by an actuating mechanism, and the throat area of ​​the guide vane is changed accordingly, thereby achieving the purpose of regulating the turbine operating condition.

[0025] To achieve the above purpose, Figure 1-2As shown, the present invention provides a trailing edge telescopic turbine adjustable guide vane, comprising: a hub 3, a casing 4 and a guide vane blade; the guide vane blade is divided into a guide vane body 1 and a trailing edge telescopic section 2; the front end of the trailing edge telescopic section 2 is inserted into the guide vane body 1 and is slidably connected to the guide vane body 1; a hub guide groove 5 is provided on the hub 3, and an engine gate guide groove is provided on the engine gate, the blade root end of the trailing edge telescopic section 2 is slidably set in the hub guide groove 5, and the blade tip of the trailing edge telescopic section 2 is slidably set in the engine gate guide groove.

[0026] The tip of the trailing edge telescopic section 2 is fixed with a sealing plate 7 and a driving handle 8. The casing guide groove 6 guides the trailing edge telescopic section 2 to move along the arc, and the sealing plate 7 can be appropriately deformed according to the small change in the curvature of the casing 4. The sealing plate 7 ensures that the trailing edge telescopic section 2 forms a seal with the casing guide groove 6 during the movement, meeting the sealing requirements. The outer ring of the casing 4 is arranged with an actuator, and the driving arm of the actuator is connected to the driving handle 8 to drive the trailing edge telescopic section 2 to move along the casing guide groove 6.

[0027] To further optimize the technical solution, a stop is provided at the front end of the trailing edge telescopic section 2 to limit the longest extension position of the trailing edge telescopic section 2.

[0028] To further optimize the technical solution, ribs are provided on both the pressure surface side and the suction surface side of the guide vane body 1 to limit the longest retracted position of the trailing edge telescopic section 2.

[0029] To further optimize the technical solution, the chord length of the trailing edge telescopic section 2 does not exceed 30% of the total chord length of the guide vane blade. The total height of the trailing edge telescopic section 2 is greater than the height of the meridian flow channel. During the telescopic process of the trailing edge telescopic section 2, its blade root end and blade tip always slide in the hub guide groove 5 and the casing guide groove 6.

[0030] To further optimize the technical solution, since the channel between the two guide vane blades is of a contraction type, the flow direction position of the trailing edge of the trailing edge telescopic section 2 is the turbine throat. When the trailing edge telescopic section 2 is retracted into the guide vane body 1, the turbine throat moves upstream accordingly, and the throat area gradually increases; when the trailing edge telescopic section 2 is completely retracted into the guide vane body 1, the turbine throat area increases to a maximum value. The longest extension position and the longest retraction position of the trailing edge telescopic section 2 determine the range of variation of the turbine throat area. When the trailing edge telescopic section 2 moves to the most downstream position, the guide vane body 1 and the adjacent guide vane blades form a minimum throat area state (the minimum area is recorded as A min ), when it moves to the most upstream position, that is, it is completely retracted into the guide vane body 1, the guide vane body 1 and the adjacent guide vane blades form a state of maximum throat area (the maximum area is recorded as A max ).

[0031] The trailing edge telescopic turbine adjustable guide vane of the present invention utilizes the upstream and downstream movement of the trailing edge telescopic section to change the area of ​​the turbine throat, which can realize the turbine variable operating condition adjustment capability and meet the overall requirements of the engine. During the operating condition adjustment process, the trailing edge telescopic turbine does not generate leakage flow, and can maintain the flow structure of the guide vane end area without significant changes, without significantly increasing the additional aerodynamic loss of the guide vane end area. The present invention has a high engineering application value in controlling leakage losses of turbine adjustable guide vanes, and has a positive impact on improving the aerodynamic performance of the engine.

[0032] The specific design process of the trailing edge telescopic turbine adjustable guide vanes is as follows:

[0033] Step 1: Design of the guide vane blade reference blade shape. On the basis of the conventional design method, the following points also need to be considered: First, to facilitate the upstream and downstream movement of the trailing edge telescopic section, the guide vane blade meridian flow channel is made into a form of equal outer diameter; second, the blade channel between the two guide vane blades is a contraction channel, the channel area gradually decreases from the leading edge to the trailing edge, and the aerodynamic throat is located at the trailing edge; third, to facilitate the trailing edge telescopic section to be retracted into the guide vane body, the guide vane outlet is designed with equal outlet angles along the blade height distribution to ensure that the guide vane reference blade shape near the trailing edge is almost free of distortion; fourth, to facilitate the upstream and downstream movement of the trailing edge telescopic section, the middle arc line of the guide vane reference blade shape at the moving trajectory of the trailing edge telescopic section is designed to be an arc shape.

[0034] Step 2: Calculate the blade passage area A at each flow direction position of the guide vane reference blade profile sw , according to the flow adjustment range requirements of the adjustable guide vane, determine the starting position of the trailing edge expansion section. If the flow adjustment range is required to be α%, then

[0035] A sw =A max =A min ×(1+α%)

[0036] Then according to A sw Determine the flow direction position, which is the starting position of the trailing edge expansion section.

[0037] Due to the limitations of the mid-arc trajectory, the torsional blade structure, and the cooling air channel inside the blade, in order to ensure that the trailing edge telescopic section can be completely retracted into the guide vane body, its chord length does not exceed 30% of the total chord length of the guide vane. Under this constraint, for a given guide vane reference blade shape, there is an upper limit to the flow regulation capacity, that is, the flow regulation range is

[0038]

[0039] A st,30％ It is the blade passage area at the starting position when the chord length of the trailing edge expansion section is 30% of the total chord length of the guide vane.

[0040] Step 3: In A maxThe guide vane blade reference blade profile is divided into two parts: the guide vane body and the trailing edge expansion section. The guide vane body is chamfered at the dividing point. Ribs are provided on the pressure side and the suction side of the guide vane body to limit the maximum retracted position of the trailing edge expansion section. The front end of the trailing edge expansion section is provided with a stop to limit the maximum extended position of the trailing edge expansion section. Figure 3 and Figure 4 shown.

[0041] Step 4: Arrange a guide groove on the hub wall corresponding to the trailing edge telescopic section, and arrange a guide groove on the corresponding casing wall to meet the requirement that the trailing edge telescopic section slides along the arc in the groove to the maximum contraction position.

[0042] Step 5: Arrange a sealing plate and a driving handle at the top of the trailing edge telescopic section. The sealing plate can completely cover the casing guide groove in the moving area of ​​the trailing edge telescopic section, and can be appropriately deformed according to the small change in the casing curvature to meet the sealing requirements. The driving handle is located at the top of the casing end of the trailing edge telescopic section. An actuator can be arranged on the outer ring of the casing, and the driving arm is connected to the driving handle to drive the trailing edge telescopic section to move along the casing guide groove.

[0043] The trailing edge telescopic turbine adjustable guide vane obtained through the above design process can change the turbine throat area by moving the trailing edge telescopic section. The specific implementation form is: since the channel between the two guide vane blades is a contraction type, the flow direction position of the trailing edge of the trailing edge telescopic section is the turbine throat. When the trailing edge telescopic section is retracted into the guide vane body, the turbine throat moves upstream accordingly, and the throat area gradually increases. When the trailing edge telescopic section is completely retracted into the guide vane body, the turbine throat area increases to the maximum value. The longest extension position and the longest retraction position of the trailing edge telescopic section determine the range of change of the turbine throat area.

[0044] The above description is only a preferred embodiment of the present invention and does not limit the technical scope of the present invention. Therefore, any slight modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A trailing edge telescopic turbine adjustable guide vane, characterized in that: include: A wheel hub, a casing and guide vane blades; the guide vane blades are divided into two parts, a guide vane body and a trailing edge telescopic section; the front end of the trailing edge telescopic section is inserted into the guide vane body and is slidably connected to the guide vane body; a wheel hub guide groove is provided on the wheel hub, and a machine brake guide groove is provided on the machine brake, the root end of the trailing edge telescopic section is slidably set in the wheel hub guide groove, and the tip end of the trailing edge telescopic section is slidably set in the machine brake guide groove.

2. The trailing edge telescopic turbine adjustable guide vane according to claim 1, characterized in that: A sealing plate and a driving handle are fixed to the tip of the trailing edge telescopic section blade.

3. The trailing edge telescopic turbine adjustable guide vane according to claim 2, characterized in that: The outer ring of the casing is provided with an actuator, and the driving arm of the actuator is connected to the driving handle to drive the trailing edge telescopic section to move along the casing guide groove.

4. A trailing edge telescopic turbine adjustable guide vane as claimed in claim 2 or 3, characterized in that: A stop is provided at the front end of the trailing edge telescopic section to limit the longest extension position of the trailing edge telescopic section.

5. The trailing edge telescopic turbine adjustable guide vane according to claim 4, characterized in that: Ribs are arranged on both the pressure surface side and the suction surface side of the guide vane body to limit the longest retracted position of the trailing edge telescopic section.

6. A trailing edge telescopic turbine adjustable guide vane as claimed in claim 1 or 5, characterized in that: The chord length of the trailing edge expansion section shall not exceed 30% of the total chord length of the guide vane blade.

7. The trailing edge telescopic turbine adjustable guide vane according to claim 6, characterized in that: The channel between the two guide vane blades is of a contraction type, and the flow direction position of the trailing edge of the trailing edge expansion section is the turbine throat. When the trailing edge expansion section retracts into the guide vane body, the turbine throat moves upstream accordingly, and the throat area gradually increases; when the trailing edge expansion section is completely retracted into the guide vane body, the turbine throat area increases to the maximum value.

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