Turbine modeling method based on weakened trailing edge shock waves

Abstract

The invention relates to a turbine modeling method based on weakening of trailing edge shock waves. The invention relates to the technical field of turbine modeling, and in view of imperfection of a turbine design method, the design complexity is reduced as much as possible. According to the method, trailing edge shock waves of an original blade profile are analyzed, the trailing edge shock waves are divided into inner tail shock waves, outer tail shock waves and reflection shock waves, under the given working condition, the strength of the three shock waves is analyzed, and the analysis condition is obtained; after shock wave intensity is analyzed, a framework is established according to specific analysis conditions. Smooth transition can be achieved in the design of the cascade, the trailing edge wave system of the cascade is adjusted, trailing edge shock waves are weakened, and losses are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of turbine shaping, in particular to a turbine shaping method based on weakening the shock wave at the trailing edge. Background Art

[0002] The design of aircraft engine fans and compressors is developing towards high Mach numbers and high blade tip tangential speeds. High blade tip relative Mach numbers will cause serious shock wave boundary layer interference, and the interaction between the shock wave and the boundary layer and the change in the back pressure behind the cascade have a great influence on the shape and intensity of the shock wave. Aviation gas turbine engines mainly use reaction turbines, and the gas is accelerated and expanded in both the rotor and stator channels. Transonic turbines usually have a subsonic inlet airflow and a supersonic outlet airflow. There is a transonic zone in the cascade channel, and the flow phenomenon inside the turbine rotor and stator is very similar to the nozzle flow. Under the design state, there is usually no shock wave in the turbine cascade channel, but due to uneven incoming flow or changes in operating conditions, the back pressure of the cascade channel is often different from that under the design state. The flow field in the transonic turbine blade cascade under different back pressures is similar to that of a Laval nozzle. Point j represents the design condition. At this time, the nozzle outlet pressure is equal to the downstream back pressure. When the back pressure increases, the outlet pressure is lower than the back pressure, resulting in the appearance of shock waves. The shock wave position depends on the ratio of the outlet pressure to the back pressure. When the back pressure decreases, the shock wave moves from the nozzle channel to the downstream. On the contrary, if the back pressure is lower than the nozzle outlet pressure, an expansion wave system will appear.

[0003] With the continuous development of aircraft engines, the demand for high thrust-to-weight ratio of engines is increasing. As one of the important components of aircraft engines, marine gas turbines, and marine turbochargers, the performance of turbines plays an important role in the safe and stable operation of the entire machinery. Modern turbine technology is developing in the direction of increasing the temperature and pressure of the turbine inlet and reducing the number of stages, thereby increasing the engine load. Increasing the load refers to increasing the single-stage pressure drop ratio or increasing the load factor. The increase in the pressure drop ratio can reduce the number of turbine stages, thereby reducing the number of blade rows and reducing the weight. After the number of turbine stages is reduced to a single stage, the stage load increases, and the outflow Mach number increases, which will inevitably lead to partial or even complete supersonic flow in the flow channel. The supersonic flow causes a complex shock wave structure inside the turbine blade channel, especially near the trailing edge of the blade. The loss caused by the trailing edge shock wave accounts for about 1 / 3 of the total loss. Reducing shock wave losses is an important way to improve the design level of aircraft engine turbine start-up.

[0004] The shock wave control technologies at home and abroad mainly include the following aspects:

[0005] Optimize the blade profile;

[0006] Use cooling method;

[0007] Adopt unsteady control technology.

[0008] In most of the optimization results, the trailing edge curvature problem is a very important focus, and it is also the mainstream and important solution of the current optimization scheme. Some progress has been made in the research on modifying the blade shape to reduce the shock wave intensity at home and abroad. At present, the corresponding design criteria and technical system for optimization design are not mature, and it is still impossible to finely improve the shock wave structure and intensity. It is still far from the optimal performance of the transonic turbine. It is necessary to improve the optimization design method of weakening shock waves to promote the development of transonic turbines. Summary of the invention

[0009] In view of the shortcomings of the prior art and the fact that the turbine design method is still imperfect, the present invention reduces the design complexity as much as possible, enables the blade grid to have a smooth transition in the design, adjusts the wave system at the trailing edge of the blade grid, weakens the shock wave at the trailing edge, and reduces losses.

[0010] The present invention provides a turbine shaping method based on weakening the trailing edge shock wave, and the present invention provides the following technical solutions:

[0011] A turbine shaping method based on weakening the trailing edge shock wave, the method comprising the following steps:

[0012] The original blade's trailing edge shock wave is analyzed, and the trailing edge shock wave is divided into inner tail shock wave, outer tail shock wave and reflected shock wave. Under given working conditions, the intensity of the three shock waves is analyzed to obtain the analysis results.

[0013] After analyzing the shock wave intensity, the framework is established based on the specific analysis situation.

[0014] Preferably, under given working conditions, the intensities of the three shock waves are analyzed, and the following situations are obtained during the analysis process:

[0015] Case 1: When the intensity of the reflected shock wave is stronger than that of the other two shock waves, a control frame is established near the shock wave reflection point on the suction side. When a control frame is established within the range of 20% upstream and 20% downstream of the reflection point, free-form surface modeling is performed for the curvature at the control frame.

[0016] Preferably, when the reflected shock wave is stronger than the inner tail shock wave and the outer tail shock wave, a control 3×3×3 frame is established near the reflection point, but considering that the control point does not appear inside the entity, only the wrapped entity is selected, and the actual number of control points on the frame is 24 points;

[0017] In order to maintain the closedness of the frame, 26 points are set; the reflection point at 50% of the blade height is the midpoint of the frame. This point is only a positioning point and does not participate in FFD; the frame takes the upstream 20% and the downstream 20% along the chord length as the front and rear boundaries; the upper and lower boundaries are set within the range of no more than 2.5-5% of the leaf height distance between the blade top and the blade root; the structure near the suction side reflection point is changed by applying a certain displacement vector in the X, Y, and Z directions to the control point.

[0018] Preferably, under given working conditions, the intensities of the three shock waves are analyzed, and the following situations are obtained during the analysis process:

[0019] Case 2: When the intensity of the reflected shock wave is not high, but the intensity of the inner tail shock wave and the outer tail shock wave is high, it is necessary to establish a control frame at the trailing edge of the original blade profile and change the shape of the trailing edge by deforming the free surface to weaken the trailing edge strength.

[0020] Preferably, for case 2, the intensity of the inner tail shock wave and the outer tail shock wave is higher than the intensity of the reflected shock wave, then a control frame is established near the trailing edge, which wraps the entire trailing edge part. Similarly, there is no situation where the control point appears inside the entity. The free-form surface modeling takes the trailing edge point at 50% of the blade height as the center point, and the front and rear boundaries are set at a distance of 5% of the chord length from the center point. The upper and lower boundaries are the same as above. The ffd method changes the shape of the trailing edge and the curvature parameters.

[0021] Preferably, under given working conditions, the intensities of the three shock waves are analyzed, and the following situations are obtained during the analysis process:

[0022] Case 3: When the shock wave intensity cannot be reduced by free surface deformation, it proves that the shock wave intensity is related to the throat area where the tail and suction sides of the pressure surfaces of the two adjacent blades are located, that is, it is related to the upstream flow. At this time, it is necessary to establish the trailing edge of the pressure side near the throat and the suction side in the same frame and improve the shape through free surface deformation.

[0023] Preferably, for case 3, a control framework is established for the throat composed of two adjacent blades, a center point is created with the center line of the flow channel at 50% of the blade height, and the boundary is set based on the suction surface and pressure surface area designed to wrap the throat. The curvature of the pressure surface is increased but the curvature of the pressure surface cannot be too large, otherwise the loss caused by the derivative effect will be greater than the loss of weakening the trailing edge shock wave; when the framework cannot perform free-form surface modeling at this moment, it is necessary to increase control points and refine the control surface.

[0024] A turbine shaping system based on weakening the trailing edge shock wave, the system comprising:

[0025] An analysis module, wherein the analysis module analyzes the trailing edge shock wave of the original blade profile, divides the trailing edge shock wave into an inner tail shock wave, an outer tail shock wave and a reflected shock wave, and analyzes the intensity of the three shock waves under a given working condition to obtain an analysis result;

[0026] A framework building module is used to build a framework according to specific analysis results after analyzing the shock wave intensity.

[0027] A computer-readable storage medium stores a computer program, which is executed by a processor to implement a turbine shaping method based on weakening the trailing edge shock wave.

[0028] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, a turbine shaping method based on weakening the trailing edge shock wave is implemented.

[0029] The present invention has the following beneficial effects:

[0030] Compared with the prior art, the present invention has the following advantages:

[0031] Under the premise of meeting the design requirements, the present invention establishes an overall design for the traditional turbine shape of aircraft engines. It does not only select a certain blade height to modify the blade profile curve and then construct a smooth surface. The FFD (free surface deformation) method is used to further optimize the current turbine design method. This method does not need to intercept the blade profile curve at the continuous blade height to give all the specific parameters, but selects the moving point for vector displacement, which affects the deformation of the controlled surface near the point. It is expected to obtain a turbine blade shape that is different from the past, providing a new idea for the future turbine shape design based on weakening the trailing edge shock wave. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 It shows the design concept and flow chart based on the turbine shaping method that weakens the shock wave at the trailing edge;

[0034] Figure 2 A schematic diagram showing the control framework established for 20% upstream and 20% downstream of the suction side reflection point, i.e., step 2;

[0035] Figure 3 Shown is the control frame at the trailing edge;

[0036] Figure 4 The control frame at the throat is shown as the pressure and suction sides combined. DETAILED DESCRIPTION

[0037] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. 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.

[0038] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0039] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0040] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0041] The present invention is described in detail below in conjunction with specific embodiments. Specific embodiment one:

[0043] according to Figures 1 to 4 As shown, the specific optimization technical solution adopted by the present invention to solve the above technical problems is: the present invention relates to a turbine shaping method based on weakening the trailing edge shock wave.

[0044] A turbine shaping method based on weakening the trailing edge shock wave, the method comprising the following steps:

[0045] The original blade's trailing edge shock wave is analyzed, and the trailing edge shock wave is divided into inner tail shock wave, outer tail shock wave and reflected shock wave. Under given working conditions, the intensity of the three shock waves is analyzed to obtain the analysis results.

[0046] After analyzing the shock wave intensity, the framework is established based on the specific analysis situation.

[0047] Under the premise of meeting the design requirements, the present invention establishes an overall design for the traditional turbine shape of aircraft engines. It does not only select a certain blade height to modify the blade profile curve and then construct a smooth surface. The FFD (free surface deformation) method is used to further optimize the current turbine design method. This method does not need to intercept the blade profile curve at the continuous blade height to give all the specific parameters, but selects the moving point for vector displacement, which affects the deformation of the controlled surface near the point. It is expected to obtain a turbine blade shape that is different from the past, providing a new idea for the future turbine shape design based on weakening the trailing edge shock wave. Specific embodiment 2:

[0049] The difference between the second embodiment of the present application and the first embodiment is that:

[0050] Under given working conditions, the intensity of the three shock waves is analyzed, and the following results are obtained during the analysis:

[0051] Case 1: When the intensity of the reflected shock wave is stronger than that of the other two shock waves, a control frame is established near the shock wave reflection point on the suction side. When a control frame is established within the range of 20% upstream and 20% downstream of the reflection point, free-form surface modeling is performed for the curvature at the control frame. Specific embodiment three:

[0053] The difference between the third embodiment of the present application and the second embodiment is that:

[0054] When the reflected shock wave is stronger than the inner and outer tail shock waves, a control 3×3×3 frame is established near the reflection point. However, considering that the control points do not appear inside the entity, only the wrapped entity is selected. The actual number of control points on the frame is 24 points.

[0055] In order to maintain the closedness of the frame, 26 points are set; the reflection point at 50% of the blade height is the midpoint of the frame. This point is only a positioning point and does not participate in FFD; the frame takes the upstream 20% and the downstream 20% along the chord length as the front and rear boundaries; the upper and lower boundaries are set within the range of no more than 2.5-5% of the leaf height distance between the blade top and the blade root; the structure near the suction side reflection point is changed by applying a certain displacement vector in the X, Y, and Z directions to the control point. Specific embodiment four:

[0057] The difference between the fourth embodiment of the present application and the third embodiment is that:

[0058] Under given working conditions, the intensity of the three shock waves is analyzed, and the following results are obtained during the analysis:

[0059] Case 2: When the intensity of the reflected shock wave is not high, but the intensity of the inner tail shock wave and the outer tail shock wave is high, it is necessary to establish a control frame at the trailing edge of the original blade profile and change the shape of the trailing edge by deforming the free surface to weaken the trailing edge strength. Specific embodiment five:

[0061] The difference between the fifth embodiment of the present invention and the fourth embodiment is that:

[0062] For case 2, the intensity of the inner and outer tail shocks is higher than that of the reflected shock, so a control frame is established near the trailing edge, which wraps the entire trailing edge. Similarly, there is no control point inside the entity. The free-form surface modeling takes the trailing edge point at 50% of the blade height as the center point, and sets the front and rear boundaries at a distance of 5% of the chord length from the center point. The upper and lower boundaries are the same as above. The ffd method changes the shape of the trailing edge and the curvature parameters. Specific embodiment six:

[0064] The difference between the sixth embodiment of the present invention and the fifth embodiment is that:

[0065] Under given working conditions, the intensity of the three shock waves is analyzed, and the following results are obtained during the analysis:

[0066] Case 3: When the shock wave intensity cannot be reduced by free surface deformation, it proves that the shock wave intensity is related to the throat area where the tail and suction sides of the pressure surfaces of the two adjacent blades are located, that is, it is related to the upstream flow. At this time, it is necessary to establish the trailing edge of the pressure side near the throat and the suction side in the same frame and improve the shape through free surface deformation. Specific embodiment seven:

[0068] The difference between the seventh embodiment of the present invention and the sixth embodiment is that:

[0069] For case 3, a control framework is established for the throat composed of two adjacent blades, and the center point is created with the center line of the flow channel at 50% of the blade height. The boundary is set based on the suction surface and pressure surface area designed to wrap the throat. The curvature of the pressure surface is increased, but the curvature of the pressure surface cannot be too large, otherwise the loss caused by the derivative effect will be greater than the loss of weakening the trailing edge shock wave; when the framework cannot perform free-form surface modeling at this moment, it is necessary to increase control points and refine the control surface. Specific embodiment eight:

[0071] The difference between the eighth embodiment of the present invention and the seventh embodiment is that:

[0072] The present invention provides a turbine shaping system based on weakening the trailing edge shock wave, the system comprising:

[0073] An analysis module, wherein the analysis module analyzes the trailing edge shock wave of the original blade profile, divides the trailing edge shock wave into an inner tail shock wave, an outer tail shock wave and a reflected shock wave, and analyzes the intensity of the three shock waves under a given working condition to obtain an analysis result;

[0074] A framework building module is used to build a framework according to specific analysis results after analyzing the shock wave intensity. Specific embodiment nine:

[0076] The difference between the ninth embodiment of the present invention and the eighth embodiment is that:

[0077] The present invention provides a computer-readable storage medium on which a computer program is stored. The program is executed by a processor to implement a turbine shaping method based on weakening the trailing edge shock wave.

[0078] The method comprises the following steps:

[0079] The original blade's trailing edge shock wave is analyzed, and the trailing edge shock wave is divided into inner tail shock wave, outer tail shock wave and reflected shock wave. Under given working conditions, the intensity of the three shock waves is analyzed to obtain the analysis results.

[0080] After analyzing the shock wave intensity, the framework is established based on the specific analysis situation. Specific embodiment ten:

[0082] The difference between the tenth embodiment of the present invention and the ninth embodiment is that:

[0083] The present invention provides a computer device, comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, a turbine shaping method based on weakening the trailing edge shock wave is implemented.

[0084] The method comprises the following steps:

[0085] The original blade's trailing edge shock wave is analyzed, and the trailing edge shock wave is divided into inner tail shock wave, outer tail shock wave and reflected shock wave. Under given working conditions, the intensity of the three shock waves is analyzed to obtain the analysis results.

[0086] After analyzing the shock wave intensity, the framework is established based on the specific analysis situation. Specific embodiment eleven:

[0088] The difference between the eleventh embodiment of the present invention and the tenth embodiment is that:

[0089] In view of the fact that the turbine design method is still imperfect, the present invention provides a design scheme for the turbine blade cascade blade shape, which reduces the design complexity as much as possible, enables the blade cascade to have a smooth transition in the design, adjusts the wave system of the blade cascade trailing edge, weakens the trailing edge shock wave, and reduces losses.

[0090] The present invention uses the FFD (Free-Form Deformation) method to change the blade curvature to optimize the blade row design. A control framework is established for the entire turbine blade row, and control points are set at the same time. The density of the control points can be set according to the degree of refinement of the design.

[0091] Select to set 26 points. After setting the points, select the vector direction of the points to be changed for the parameters to be changed later (pressure surface curvature, suction surface curvature) and move them.

[0092] The specific steps include:

[0093] Step 1: First, analyze the trailing edge shock wave of the original blade. The trailing edge shock wave is divided into inner tail shock wave, outer tail shock wave and reflected shock wave. Under given working conditions, the intensity of the three shock waves is analyzed. During the analysis process, it is roughly divided into three situations.

[0094] Case 1: If the intensity of the reflected shock wave is stronger than the other two shock waves, a control frame is established near the shock wave reflection point on the suction side, such as establishing a control frame within the range of 20% upstream and 20% downstream of the reflection point, such as Figure 1 As shown, free-form surface modeling is performed for the curvature at the control frame.

[0095] Case 2: The reflected shock wave is not strong, but the inner and outer tail shock waves are strong. In this case, it is necessary to establish a control framework at the trailing edge of the original blade, such as Figure 2 As shown, the shape of the trailing edge is then changed by free-form surface deformation to weaken the strength of the trailing edge, for example, the trailing edge is changed into an ellipse, a rectangle or other shapes.

[0096] Case 3: If the shock wave intensity is not reduced by free surface deformation in the above two cases, it proves that the shock wave intensity is related to the throat area where the tail and suction sides of the two adjacent blades are located, that is, it is related to the upstream flow. In this case, it is necessary to establish the pressure side trailing edge near the throat and the suction side in the same framework and improve the shape through free surface deformation. The established framework is as follows Figure 3 As shown,

[0097] Step 2: After analyzing the shock wave intensity, further explain where and how to establish the frame.

[0098] For case 1, when the reflected shock wave is stronger than the inner tail shock wave and the outer tail shock wave, a control 3×3×3 frame is established near the reflection point. However, considering that the control point does not appear inside the entity, only the wrapped entity is selected, and the actual number of control points on the frame is 24. In order to maintain the closedness of the frame, 26 points are set. The reflection point at 50% of the blade height is taken as the midpoint of the frame (this point is only a positioning point and does not participate in ffd); along the direction of the chord length of the frame, the upstream 20% and the downstream 20% are taken as the front and rear boundaries; the upper and lower boundaries are set within the range of no more than 2.5-5% of the blade height distance between the blade top and the blade root. For example Figure 1 By applying a certain displacement vector in the X, Y, and Z directions to the control point, the structure near the reflection point on the suction side is changed.

[0099] For case 2, the intensity of the inner and outer tail shock waves is higher than that of the reflected shock wave. Therefore, a control frame is established near the trailing edge. The control frame wraps the entire trailing edge. Similarly, there is no control point inside the entity. The steps of free-form surface modeling are similar to those of case 1. The trailing edge point at 50% of the blade height is taken as the center point, and the front and rear boundaries are set at a distance of 5% of the chord length from the center point. The upper and lower boundaries are the same as above. The ffd method is used to change the shape, curvature and other parameters of the trailing edge. The control frame is as follows: Figure 2 shown.

[0100] For case 3, the intensity of the trailing edge shock wave is not weakened after changing the reflection point and the trailing edge related parameters, which proves that the intensity of the trailing edge shock wave is related to the upstream flow. In a transonic turbine, the external tail shock wave has a greater impact on the total shock wave loss than the internal tail shock wave. Increasing the upstream shock wave intensity can effectively weaken the intensity of the downstream external tail shock wave, thereby reducing the total shock wave loss. At this time, it is necessary to establish a control framework for the throat composed of two adjacent blades, and create a center point with the center line of the flow channel at 50% of the blade height. The boundary setting is based on the suction surface and pressure surface area designed to wrap the throat. Increase the curvature of the pressure surface, but the curvature of the pressure surface cannot be too large, otherwise the loss caused by the derivative effect will be greater than the loss of weakening the trailing edge shock wave. If the framework cannot perform free-form surface modeling well at this moment, it is necessary to add control points and refine the control surface. The control framework is such as Figure 3 shown.

[0101] For the refinement of the blade profile of the pressure side and the suction side, more definition points can be added and the multi-point optimization design can make the turbine blade grid design more reasonable.

[0102] This application uses the FFD (free surface deformation) method to optimize the design of the engine turbine blade. The above is only an illustrative description of the principle and effect of this application, but not a limitation on the specific parameter design of the turbine. Therefore, anyone with ordinary knowledge in the relevant technical field can make all adjustments and modifications without departing from the technical ideas described in this application.

[0103] The present invention provides a turbine modeling method based on weakening the shock wave at the trailing edge, and controls the geometric shape of the object by establishing a control frame and controlling the points on the frame grid. The method can move and deform the main cross section while making the secondary cross section transition smoothly during the design, providing a design idea.

[0104] The above is only a preferred implementation of a turbine shaping method based on weakening the trailing edge shock wave. The protection scope of a turbine shaping method based on weakening the trailing edge shock wave is not limited to the above embodiment. All technical solutions under this idea belong to the protection scope of the present invention. It should be pointed out that for those skilled in the art, several improvements and changes without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A turbine shaping method based on weakening the trailing edge shock wave, characterized by: The method comprises the following steps: The original blade's trailing edge shock wave is analyzed, and the trailing edge shock wave is divided into inner tail shock wave, outer tail shock wave and reflected shock wave. Under given working conditions, the intensity of the three shock waves is analyzed to obtain the analysis results. After analyzing the shock wave intensity, the framework is established based on the specific analysis situation.

2. The method according to claim 1, characterized in that: The following results were obtained during the analysis: Case 1: When the intensity of the reflected shock wave is stronger than that of the other two shock waves, a control frame is established near the shock wave reflection point on the suction side. When a control frame is established within the range of 20% upstream and 20% downstream of the reflection point, free-form surface modeling is performed for the curvature at the control frame.

3. The method according to claim 2, characterized in that: When the reflected shock wave is stronger than the inner and outer tail shock waves, a control 3×3×3 frame is established near the reflection point, and only the wrapped entity is selected. The actual number of control points on the frame is 24 points. In order to maintain the closedness of the frame, 26 points are set; the reflection point at 50% of the blade height is the midpoint of the frame. This point is only a positioning point and does not participate in FFD; the frame takes the upstream 20% and the downstream 20% along the chord length as the front and rear boundaries; the upper and lower boundaries are set within the range of no more than 2.5-5% of the leaf height distance between the blade top and the blade root; the structure near the suction side reflection point is changed by applying a certain displacement vector in the X, Y, and Z directions to the control point.

4. The method according to claim 1, characterized in that: The following results were obtained during the analysis: Case 2: When the intensity of the reflected shock wave is not high, but the intensity of the inner tail shock wave and the outer tail shock wave is high, it is necessary to establish a control frame at the trailing edge of the original blade profile and change the shape of the trailing edge by deforming the free surface to weaken the trailing edge strength.

5. The method according to claim 4, characterized in that: For case 2, a control frame is established near the trailing edge, which wraps the entire trailing edge. There is no control point inside the entity. The free-form surface modeling takes the trailing edge point at 50% of the blade height as the center point, and the front and rear boundaries are set at a distance of 5% of the chord length from the center point. The upper and lower boundaries are the same as above. The ffd method changes the shape of the trailing edge and the curvature parameters.

6. The method according to claim 1, characterized in that: The following results were obtained during the analysis: Case 3: The pressure side trailing edge near the throat is built in the same frame as the suction side, and the shape is improved by free-form surface deformation.

7. The method according to claim 5, characterized in that: For case 3, a control framework is established for the throat composed of two adjacent blades, and the center point is created with the center line of the flow channel at 50% of the blade height. The boundary is set based on the suction surface and pressure surface area designed to wrap the throat. If the framework cannot perform free-form surface modeling at this moment, it is necessary to increase control points and refine the control surface.

8. A turbine shaping system based on weakening the trailing edge shock wave, characterized by: The system comprises: An analysis module, wherein the analysis module analyzes the trailing edge shock wave of the original blade profile, divides the trailing edge shock wave into an inner tail shock wave, an outer tail shock wave and a reflected shock wave, and analyzes the intensity of the three shock waves under a given working condition to obtain an analysis result; A framework building module, after analyzing the shock wave intensity, establishes the framework according to specific analysis conditions.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement the method according to claims 1-7.

10. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the method of claims 1-7 is implemented.

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