A turbine integrated transition piece blade and method of designing the same

Abstract

The application discloses a turbine integrated transition section blade and a design method thereof, and relates to the technical field of gas turbine engines, and comprises the following steps: S1: determining corresponding inlet flow parameters based on a design working condition; S2: determining a blade profile of the transition section blade by corresponding design of the radial distribution of different blade profile parameters according to the given change of the inlet flow parameters; S3: lengthening the chord length of the blade above the 0.5 section of the blade height; and S4: designing a turbine integrated transition section large blade. Under the condition of strong non-uniform inlet flow (the Mach number sharply increases along the path in the upper part of the blade), the application can realize the target of low total pressure loss and high aerodynamic efficiency, has the functions of structure and aerodynamics, and effectively shortens the axial length of the engine and reduces the weight.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of gas turbine engine technology, and more particularly to a turbine integrated transition section blade and a design method thereof. BACKGROUND

[0002] In the field of aero-engine, the speed difference of high and low pressure turbine shafts leads to the difference of inner diameters of high and low pressure turbines, and the transition section is needed to connect the two. The transition section is affected by the non-uniform flow field at the outlet of the upstream high pressure turbine, and at the same time needs to realize the function of a guide vane to provide suitable flow conditions for the downstream low pressure turbine. In addition, various pipelines and supporting members need to be installed in the transition section to meet the structural requirements of the oil system or support system. With the progress of aero-engine technology, the integrated design technology of the transition section can effectively shorten the length of the engine and reduce the weight, but brings technical challenges to the profile design of the turbine large blade support plate. Separation is prone to occur in the corner area of the transition section passage with a large expansion angle.

[0003] With the further improvement of the cycle parameters of the aero-engine, the performance design index of the turbine component is also getting higher and higher. In order to meet the specific engine power overall index requirement, the high pressure turbine will adopt high reverse force design, which in turn leads to a very high Mach number at the outlet of the high pressure turbine. At this time, if the conventional profile design idea is adopted for the turbine integrated transition section downstream of the high pressure turbine, the corner separation will occur, resulting in large transition section loss and failing to meet the engine performance index requirement.

[0004] Therefore, how to design a turbine integrated transition section blade that meets the requirements of high performance and low loss and effectively shortens the axial length of the engine and reduces the weight is a technical problem that needs to be solved by those skilled in the art. SUMMARY

[0005] Therefore, the present application provides a turbine integrated transition section blade and a design method thereof, which solves the problems in the background art.

[0006] In order to achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0007] A design method of a turbine integrated transition section blade, comprising the following steps:

[0008] S1: determining the corresponding inlet flow parameters based on the design operating condition;

[0009] S2: determining the profile of the transition section blade by corresponding to the design of different profile parameters along the radial direction through the given change of the inlet flow parameters;

[0010] S3: lengthening the chord length of the blade above the 0.5 section of the blade height;

[0011] S4: design large blade of turbine integrated transition section.

[0012] Optionally, in S1, the inlet Mach number of the transition section blade linearly increases in the region above the 0.5 section of the blade height until reaching the end wall region, and the inlet flow angle of the transition section blade linearly decreases.

[0013] Optionally, in S2, the profile parameters include: number of blades, profile section height, inlet configuration angle, inlet wedge angle, leading edge fillet radius, outlet configuration angle, trailing edge fillet radius, bending angle, installation angle, throat width and axial chord length.

[0014] Optionally, the inlet configuration angle is the angle β between the tangent of the mean camber line at the inlet edge of the blade and the mean line 1k , taking the 0.5 section of the blade height as the turning point, showing a reverse "C-type" curve distribution characteristic from the blade root to the blade tip;

[0015] The outlet configuration angle is the angle β between the tangent of the mean camber line at the outlet edge of the blade and the mean line 2k , taking the 0.5 section of the blade height as the turning point, showing a reverse "C-type" curve distribution characteristic from the blade root to the blade tip under the influence of the radial variation law of the inlet configuration angle;

[0016] The installation angle is the angle γ between the profile chord line and the mean line, taking the 0.5 section of the blade height as the turning point, showing a reverse "C-type" curve distribution characteristic from the blade root to the blade tip;

[0017] The throat width is the distance a from the tangent point of the blade basin profile line and the trailing edge fillet to the adjacent blade back, taking the 0.5 section of the blade height as the turning point, showing a reverse "C-type" curve distribution characteristic from the blade root to the blade tip;

[0018] The bending angle is the angle δ between the tangent of the mean camber line at the leading edge point and the tangent of the mean camber line at the trailing edge point, taking the 0.5 section of the blade height as the turning point, showing a reverse "C-type" curve distribution characteristic from the blade root to the blade tip;

[0019] The axial chord length is the length bx of the blade projected onto the turbine axis, taking the 0.5 section of the blade height as the turning point, showing a "C-type" curve distribution characteristic from the blade root to the blade tip.

[0020] Optionally, in S3, based on the completion of the profile design of the transition section blade, the installation angle, the bending angle, the throat width are reduced, and the axial chord length is increased, so as to weaken the sharp deceleration of the airflow in the expansion passage and prolong the residence time of the airflow in the adaptation passage area.

[0021] Optionally, in S4, the number of pipes required for structural function is determined, the number of large blades is determined, the large blades maintain the same profile as the small blades in the rear region of the blades, and the number of large blades is the common divisor of the number of small blades.

[0022] A turbine integrated transition section blade is designed by the design method of the turbine integrated transition section blade according to any one of the above.

[0023] Compared with the prior art, the turbine integrated transition section blade and the design method thereof provided by the application can realize low total pressure loss and high aerodynamic efficiency under the condition of strong non-uniform inlet flow (the Mach number sharply increases along the upper part of the blade), and has structural and aerodynamic functions, effectively shortens the axial length of the engine and reduces the weight. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only constitute the embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of the provided drawings.

[0025] Figure 1 A design flowchart of the turbine integrated transition section blade provided by the application is provided.

[0026] Figure 2 A blade different blade height (dimensionless) section schematic diagram provided by the application is provided.

[0027] Figure 3a A schematic diagram of the change of the inlet flow Ma provided by the application is provided.

[0028] Figure 3b A schematic diagram of the change of the inlet flow angle provided by the application is provided.

[0029] Figure 4 A schematic diagram of the blade profile parameter provided by the application is provided.

[0030] Figure 5 A schematic diagram of the radial distribution rule of the transition section blade profile inlet configuration angle provided by the application is provided.

[0031] Figure 6 A schematic diagram of the radial distribution rule of the transition section blade profile outlet configuration angle provided by the application is provided.

[0032] Figure 7 A schematic diagram of the radial distribution rule of the transition section blade profile installation angle provided by the application is provided.

[0033] Figure 8 A schematic diagram of the radial distribution rule of the transition section blade profile throat width provided by the application is provided.

[0034] Figure 9A radial distribution law schematic diagram of a bending angle of a profile of a transition section blade provided by the present application is shown in the figure;

[0035] Figure 10a A blade inlet direction view of a three-dimensional blade modeling provided by the present application is shown in the figure;

[0036] Figure 10b A blade basin side view of the three-dimensional blade modeling provided by the present application is shown in the figure;

[0037] Figure 10c A blade back side view of the three-dimensional blade modeling provided by the present application is shown in the figure;

[0038] Figure 11 A comparison chart before and after the mounting angle optimization provided by the present application is shown in the figure;

[0039] Figure 12 A comparison chart before and after the bending angle optimization provided by the present application is shown in the figure;

[0040] Figure 13 A comparison chart before and after the throat width optimization provided by the present application is shown in the figure;

[0041] Figure 14 A comparison chart before and after the axial chord length optimization provided by the present application is shown in the figure;

[0042] Figure 15a A schematic diagram of a blade surface streamline before the optimization provided by the present application is shown in the figure;

[0043] Figure 15b A schematic diagram of a blade surface streamline after the optimization provided by the present application is shown in the figure;

[0044] Figure 16a A pressure distribution chart of a 0.1 section of a blade height before and after the blade 0.5 blade height tail lengthening provided by the present application is shown in the figure;

[0045] Figure 16b A pressure distribution chart of a 0.5 section of a blade height before and after the blade 0.5 blade height tail lengthening provided by the present application is shown in the figure;

[0046] Figure 16c A pressure distribution chart of a 0.7 section of a blade height before and after the blade 0.5 blade height tail lengthening provided by the present application is shown in the figure;

[0047] Figure 16d A pressure distribution chart of a 0.9 section of a blade height before and after the blade 0.5 blade height tail lengthening provided by the present application is shown in the figure. DETAILED DESCRIPTION

[0048] With reference to the accompanying drawings, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative effort are within the protection scope of the present application.

[0049] To meet the design requirements of high performance and low loss, the embodiments of the present application disclose a design method of a turbine integrated transition section blade, as shown in Figure 1 , which comprises the following steps:

[0050] S1: determining corresponding inlet flow parameters based on a design operating condition;

[0051] S2: determining a blade profile of the transition section blade by corresponding design of the radial distribution of different blade profile parameters with the given variation of the inlet flow parameters;

[0052] S3: lengthening the chord length of the blade above the 0.5 section of the blade height;

[0053] S4: designing a turbine integrated transition section large blade.

[0054] Next, the design scheme of the turbine integrated transition section blade shown in Figure 1 will be described in detail to have a further understanding.

[0055] 1. Inlet flow parameters (design input conditions) of the transition section blade

[0056] Generally, the inlet flow Ma (Mach number) of the transition section blade varies little within the blade passage main flow height, and local fluctuations due to the end wall secondary flow and tip leakage effects occur in the blade end region (blade section height≮0.9 and≯0.1). With reference to the blade section height (dimensionless) diagram shown in Figure 2 , for the special case in the present embodiment, the inlet flow Ma of the transition section blade linearly increases above the 0.5 section of the blade height until reaching the end wall region, and at the same time, the inlet flow angle of the transition section blade also linearly decreases above the 0.5 section of the blade height as the turning point, as shown in Figure 3a , Figure 3b .

[0057] 2. Blade profile design of the transition section blade

[0058] The 11-parameter method is used to design the turbine blade profile, which specifically includes: the number of blades, the profile section height, the inlet configuration angle, the inlet wedge angle, the leading edge small circle radius, the outlet configuration angle, the trailing edge small circle radius, the bending angle, the installation angle, the throat width, and the axial chord length. By giving the 11 parameters and determining the blade profile, the profile can be designed.

[0059] For the technical solution of the present embodiment, the distribution of the inlet configuration angle, the outlet configuration angle, the axial chord length, the installation angle, the bending angle, and the throat width along the blade height direction is compared with the conventional profile distribution, which presents an obvious "C-type" or reverse "C-type" curve distribution characteristic with the blade height 0.5 section as the turning point, so as to adapt to the high flow velocity and small inlet flow angle of the upstream high-pressure turbine outlet blade height 0.5 section and above, and further to control the flow separation in the transition section to the greatest extent; the number of blades, the profile section height, the inlet wedge angle, the leading edge small circle radius, and the trailing edge small circle radius are similar to the conventional profile design, and no additional radial rule control design is needed.

[0060] (1) As shown in Figure 4 , the inlet configuration angle is the angle β between the tangent of the middle arc line at the inlet edge of the blade and the normal line 1k , which presents a reverse "C-type" curve distribution characteristic from the blade root to the blade tip with the blade height 0.5 section as the turning point; as shown in Figure 5 , at the blade height 0.5 section, β 1k takes the average value 120° of the transition section inlet flow angle, from the middle section to the blade tip, β 1k rapidly decreases, which adapts to the linear decrease of the flow angle of the inlet flow above the blade height 0.5 section, from the blade root to the blade tip (110° to 60°).

[0061] (2) The outlet configuration angle is the angle β between the tangent of the middle arc line at the outlet edge of the blade and the normal line 2k , which presents a reverse "C-type" curve distribution characteristic from the blade root to the blade tip with the blade height 0.5 section as the turning point; as shown in Figure 6 , at the blade height 0.5 section, β 2k takes 45°, which provides a 40° flow angle for the downstream low-pressure turbine blade, and is affected by the radial variation rule of the inlet configuration angle, in order to maintain the continuity of the curvature of the blade profile, the outlet configuration angle rapidly decreases from the middle section to the blade tip, which presents a reverse "C-type" from the blade root to the blade tip (35° to 12°).

[0062] (3) The installation angle is the angle γ between the profile chord line and the normal line, which presents a reverse "C-type" curve distribution characteristic from the blade root to the blade tip with the blade height 0.5 section as the turning point; as shown in Figure 7As shown in the drawing, at the 0.5 section of the blade height, γ is taken as 56.5°, below the 0.5 section of the blade height, γ increases from the blade root to the blade tip, and above the 0.5 section of the blade height, γ gradually decreases, showing an inverse "C type" from the blade root to the blade tip (50° to 40°). The installation angle is decreased above the 0.5 section of the blade height, so that the bending degree of the front half of the blade profile is increased, the convergence degree is increased, and the pressure recovery amplitude caused by the flow passage lifting is weakened.

[0063] (4) The throat width is the distance a from the tangent point of the blade basin profile and the small circle of the trailing edge to the adjacent blade back, and shows an inverse "C type" curve distribution characteristic from the blade root to the blade tip with the 0.5 section of the blade height as the turning point; as shown in the drawing, at the 0.5 section of the blade height, a is taken as 38.2 mm, and similar to the installation angle, below the 0.5 section of the blade height, a increases from the blade root to the blade tip, and above the 0.5 section of the blade height, a gradually decreases, showing an inverse "C type" from the blade root to the blade tip (50° to 40°). Figure 8

[0064] (5) The bending angle is the included angle δ between the tangent of the middle arc line at the leading edge point and the tangent of the middle arc line at the trailing edge point, and represents the bending degree of the blade profile, showing an inverse "C type" curve distribution characteristic from the blade root to the blade tip with the 0.5 section of the blade height as the turning point; as shown in the drawing, at the 0.5 section of the blade height, δ is taken as 157°, below the 0.5 section of the blade height, δ changes little, and above the 0.5 section of the blade height, the bending angle decreases. Figure 9

[0065] (6) The axial chord length is the length bx of the blade projected onto the turbine axis, showing a "C type" curve distribution characteristic from the blade root to the blade tip with the 0.5 section of the blade height as the turning point. In the embodiment, at the 0.5 section of the blade height, bx is taken as 70 mm, below the 0.5 section of the blade height, bx changes little, and above the 0.5 section of the blade height, bx increases.

[0066] By controlling the above 6 parameters in the radial direction in the C type rule, the three-dimensional blade modeling obtained is as shown in the drawing. Figure 10a Figure 10b Figure 10c As shown in the drawing, the blade inlet direction shows a clear C type.

[0067] 3, further lengthening the blade chord length above the 0.5 section of the blade height

[0068] ​​​​Corner separation is often prone to occur in the leading edge corner area of ​​the transition section blade basin. For the transition section blade of this embodiment, the inlet flow Ma is high above 0.5 sections of the blade height, causing the corner separation vortex to diverge after the airflow expands, covering most of the upper half of the blade. To address this, this embodiment proposes a solution. Based on the above-mentioned transition section blade profile design, the mounting angle, bend angle, and throat width are further reduced, and the axial chord length is increased. This reduces the rapid deceleration of the airflow in the expansion channel and prolongs the airflow's residence time to adapt to the dramatic change in channel area, thereby weakening separation on the blade basin side.

[0069] Specifically, based on the blade design, the installation angle is further reduced from the original solution starting from the blade height 0.5 section, and the reduction amplitude is 5° at the blade height 1.0 section (blade tip section), see Figure 11 The bending angle is further reduced from the original solution starting from the section with a blade height of 0.5, and the reduction amplitude is 5° at the section with a blade height of 1.0 (blade tip section), see Figure 12 The throat width is further reduced from the original solution starting from the section at 0.5 of the blade height, and the reduction amplitude is 4.5mm at the section at 1.0 of the blade height (blade tip section), see Figure 13 The axial chord length is further increased from the original solution starting from the section at 0.5 of the blade height, and the increase amplitude is 2.5mm at the section at 1.0 of the blade height (blade tip section), see Figure 14 .

[0070] The streamlines on the blade surface are as follows Figure 15a 、 Figure 15b As shown in the figure, by lengthening the trailing edge area of ​​the blade height 0.5 section, the original open separation is weakened to a small range of closed separation in the leading edge corner area of ​​the blade basin. Figure 15a ) The total pressure loss of the blade row in the transition section is 3.87%. After optimization ( Figure 15b ) The absolute value of the total pressure loss decreased by 0.2%, and the amplitude accounted for 5%. Figure 16a 、 Figure 16b 、 Figure 16c 、 Figure 16d From the pressure distribution diagrams of different sections of the blade before and after the tail of the blade is lengthened by 0.5 blade height, it can be concluded that after the tail of the blade is lengthened by 0.5 blade height, the load distribution of the blade in the area above 0.5 blade height (taking the section of 0.7 blade height and the section of 0.9 blade height as examples) is more uniform, and the slope of the adverse pressure gradient change is smoother.

[0071] 4. Turbine integrated transition section large blade design

[0072] After the small blades are completed, the number of large blades is determined based on the number of pipelines required to provide structural functions. The large blades maintain the same profile as the small blades in the rear area of ​​the blades, and the number of large blades is a common divisor of the number of small blades.

[0073] The embodiment also provides a turbine integrated transition section blade designed by the design method of the turbine integrated transition section blade.

[0074] Finally, the three-dimensional CFD simulation results of the component show that the transition section of the technical scheme has low total pressure loss and high low-pressure turbine efficiency, and the application of the technical scheme to an aero-engine can meet the requirements of the examination index, thereby proving the feasibility of the technical scheme.

[0075] The embodiments in the specification are described in a progressive manner, and each embodiment focuses on the difference from other embodiments, and the same or similar parts of each embodiment can be referred to each other. For the device disclosed by the embodiments, since it corresponds to the method disclosed by the embodiments, the description is relatively simple, and the related parts can be referred to the method part.

[0076] The above description of the disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to the embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. That is, scaling the above features is within the scope of the present application, and reducing or increasing the specific values within the tolerance range also belongs to the scope of the present application, therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method of designing a turbine integrated transition piece vane, characterized by, The method comprises the following steps: S1: determining corresponding inlet flow parameters based on design working conditions; S2: determining the blade profile of the transition section blade by corresponding design of the radial distribution of different blade profile parameters with the given variation of the inlet flow parameters, and specifically, designing the distribution rules of the inlet construction angle, the outlet construction angle, the axial chord length, the installation angle, the bending angle, and the throat width along the blade height direction based on the C-type control law of the key design parameters, taking the 0.5-section of the blade height as the turning point; S3: lengthening the axial chord length of the blade above the 0.5-section of the blade height; based on the design of the blade profile of the transition section blade, reducing the installation angle, the bending angle, and the throat width, and increasing the axial chord length of the blade to weaken the sharp deceleration of the airflow in the expansion passage and prolong the residence time of the airflow in the adaptation passage with the dramatic change in the area; S4: designing the large blade of the turbine integrated transition section.

2. The method of designing a turbine integrated transition piece blade of claim 1, wherein, In S1, the inlet flow Mach number of the transition section blade linearly increases in the region above the 0.5-section of the blade height until reaching the end wall region, and the inlet flow angle of the transition section blade linearly decreases.

3. The method of designing a turbine integrated transition piece vane as claimed in claim 1, wherein, In S2, the blade profile parameters further include the number of blades, the blade profile section height, the inlet wedge angle, the leading edge small circle radius, and the trailing edge small circle radius.

4. The method according to claim 1, wherein The inlet structural angle is the angle between the tangent of the mid-arc line at the inlet edge of the blade and the frontal line. , with the section at 0.5 of the leaf height as the turning point, it presents an inverse C-shaped curve distribution feature from the leaf root to the leaf tip; exit configuration angle is the angle between the tangent of the mean camber line at the exit edge of the blade and the camber line With the section at 0.5 blade height as the turning point, the inlet configuration angle influences the radial variation law, showing a reverse C-shaped curve distribution characteristics from the blade root to the blade tip. mounting angle is the angle between the chord line of the blade and the horizontal line The profile of the blade is a reverse C-shaped curve from the blade root to the blade tip with the 0.5 section of the blade height as the turning point. Throat width is the distance from the intersection of the blade basin profile and the small circle of the trailing edge to the adjacent blade suction surface a The profile of the airfoil presents a reverse C-shaped curve distribution characteristic from the airfoil root to the airfoil tip with the airfoil height 0.5 section as the turning point The bending angle is the included angle between the tangent of the middle camber line at the leading edge point and the tangent of the middle camber line at the trailing edge point The distribution characteristic of the airfoil is a reverse C-shaped curve from the root to the tip with the 0.5 section of the height of the airfoil as the turning point. Blade axial chord is the length of the blade projected onto the turbine axis bx The profile of the blade is a C-shaped curve from the hub to the tip with a turning point at 50% of the blade height.

5. The method of designing a turbine integrated transition piece vane as claimed in claim 1, wherein, In S4, the number of large blades is determined according to the number of pipelines required to provide structural functions, the large blades maintain the same profile as the small blades in the rear region of the blades, and the number of large blades is the greatest common divisor of the number of small blades.

6. A turbine integrated transition piece vane, characterized by, The turbine integrated transition section blade is designed by the method according to any one of claims 1-5.

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