CN207715190U - Turbo blade - Google Patents

Abstract

The utility model provides a turbine blade, which includes a blade body, the blade body has a blade tip and a blade root, the blade tip has a blade tip plane at the top of the blade body, and a concave cavity is arranged in the turbine blade , the concave cavity is streamlined, the concave cavity has an opening, the opening is located on the blade tip plane, and the concave cavity along the cross section of the turbine blade is composed of several sections of arcs .

Description

turbine blade

technical field

The invention relates to a turbine blade, in particular to a blade tip streamline concave cavity turbine blade.

Background technique

In a gas turbine system, the turbine blades must withstand high temperature, high speed, and high pressure environments. Stable operation in such an environment is the most basic requirement for modern gas turbines for turbine performance. On this basis, improving the efficiency and life of gas turbines has become the current stage. The main problems to be considered and solved in the structural design of turbine blades.

The blades under the prior art background include solid blades and porous hollow blades. Solid blades do not consider cooling and tip loss, so the efficiency is low and the life is short; porous hollow blades are difficult to manufacture and the yield is low; in this context, considering the above problems, a new type of blade is proposed to solve the tip loss Large, difficult to manufacture and other issues.

Contents of the invention

In view of this, the present invention proposes a turbine blade with a blade-tip streamline concave cavity.

The invention provides a turbine blade, comprising a blade body, the blade body has a blade tip and a blade root, the blade tip has a blade tip plane at the top of the blade body, a concave cavity is arranged in the turbine blade, The concave cavity is streamlined, and the concave cavity has an opening, and the opening is located on the blade tip plane.

In one embodiment, said tip plane has a tip leading edge and a tip trailing edge opposite said tip leading edge, said opening has a cavity leading edge adjacent to said tip leading edge and adjacent to said tip leading edge. The concave cavity trailing edge of the blade tip trailing edge, the opening is configured in the transverse direction of the turbine blade to first expand and then contract from the concave cavity leading edge to the concave cavity trailing edge, and the concave cavity in the turbine blade The vanes are configured longitudinally to first expand and then contract from the opening to the bottom of the concave cavity, and contract toward the center of the bottom.

In one embodiment, the part of the concave cavity along the cross-section of the turbine blade is formed by several arcs.

In one embodiment, the part of the concave cavity along the cross-section of the turbine blade is composed of eight segments of arcs, including a first segment of arcs located at the leading edge of the cavity, starting from the first end arc The second section of arc, the third section of arc, the fourth section of arc, the fifth section of arc, the sixth section of arc, the seventh section of arc extending to both sides and the rear edge of the cavity The eighth arc.

In an embodiment, the cavity segment formed by the first segment of arc is used for rectification.

In an embodiment, the chamber segment formed by the second segment of arc and the third segment of arc is used to form a vortex.

In one embodiment, the cavity segment formed by the fourth arc and the fifth arc is used to develop the influence of the vortex.

In an embodiment, the cavity segment formed by the sixth arc, the seventh arc and the eighth arc is used for gentle rectification.

In one embodiment, the bottom of the concave cavity has a downward concave arc surface.

In one embodiment, an edge plate is connected to the blade root, the turbine blade has a stacking shaft, the height of the concave cavity in the longitudinal direction of the turbine blade is 8.865mm, and the bottom of the concave cavity The distance from the stacking axis is 5.16mm, the distance between the end of the edge plate and the stacking axis is 9.7mm, the point span of the front edge of the cavity is 156 degrees, and the rear edge of the cavity The point span of is 183 degrees.

To sum up, the present invention proposes a new type of turbine blade. By designing a blade tip streamline concave cavity, the advantages of the turbine blade working in a high temperature, high speed, and high pressure environment are as follows:

(1) The design of the blade tip streamline concave cavity makes the whole blade lighter, avoids the concentration of thermal stress in the environment of high temperature, high speed and high pressure, and makes the temperature field change uniform, thereby improving the life of the entire turbine blade.

(2) In a high-speed environment, the working fluid of the gas turbine will be thrown towards the tip of the blade under the action of centrifugal force, resulting in part of the fluid working fluid leaking from the gap between the tip of the blade and the stator component without doing work, resulting in a loss of turbine efficiency. decline. The design of the blade tip streamline concave cavity makes the gap between the turbine blade and the stator part form an expansion cavity, and the fluid passing through here will produce a step vortex effect, where the energy of the leaked fluid is weakened and the speed becomes slower, and then Reduce the leakage of working medium, thereby improving efficiency.

(3) The design of the streamline concave cavity at the blade tip also plays a role in frequency modulation. Each blade has its own natural vibration frequency when it rotates. Through the design of the depth and size of the streamline concave cavity at the blade tip, it can be effectively avoided. Resonance occurs in rotating parts such as turbine disks and shafts, thereby increasing the life of the unit.

Description of drawings

Fig. 1 is a front view of a turbine blade of the present invention.

Figure 2 is a top view of the turbine blade of the present invention at an angle.

Figure 3 is a cross-sectional view of a turbine blade of the present invention at an angle.

Fig. 4 is a top view of the turbine blade of the present invention at another angle.

Fig. 5 is a sectional view of the turbine blade of the present invention at another angle.

Detailed ways

Before describing the embodiments in detail, it should be understood that the present invention is not limited to the detailed structures or arrangements of elements described herein below or in the accompanying drawings. The present invention can be an embodiment implemented in other ways. Also, it should be understood that the phraseology and terminology used herein are for descriptive purposes only and should not be interpreted as limiting. The terms "including", "comprising", "having" and similar expressions used herein are meant to include the items listed thereafter, their equivalents and other additional items. In particular, when "a certain element" is described, the present invention does not limit the number of the element to one, but may also include a plurality.

As shown in FIGS. 1-5 , the present invention proposes a turbine blade, which includes a blade body 10 , a blade edge plate 16 and tenon teeth 18 . The blade body 10 and the mortise teeth 18 are respectively located on opposite sides of the blade edge plate 16 . The blade body 10 has a blade tip 12 and a blade root 14, and the fixing form of the blade root 14 and the turbine disk is fixed by a fir tree-shaped tongue and groove. Specifically, the blade root 14 is smoothly transitioned to the blade edge plate 16 , the blade edge plate 16 is curved so that the blade edge plate 16 fits the aerodynamic characteristics of the fluid, and the lower side of the blade edge plate 16 is connected to the tenons 18 .

At the tip of the blade body 10 , the blade tip 12 has a tip plane 20 with a tip leading edge 22 and a tip trailing edge 24 opposite the tip leading edge 22 . A concave cavity 26 is arranged inside the turbine blade, and the concave cavity 26 is streamlined. The concave cavity 26 has an opening 28 located on the tip plane 20 . The opening 28 has a pocket leading edge 30 adjacent the tip leading edge 22 and a pocket trailing edge 32 adjacent the tip trailing edge 24 .

In the illustrated embodiment, the blade body 10 includes a first end 34 at the tip leading edge 22 and a second end 36 at the blade tip trailing edge 24, the blade body 10 being configured from the blade body in the transverse direction of the turbine blade. First end 34 to second end 36 of 10 expand and then contract. The blade body 10 smoothly transitions from the second end 36 toward the turbine blade side to the first end 34, and the bending angle gradually increases. The thickness of the blade body 10 first increases and then decreases from the second end 36 toward the first end 34. Small, the thickness of the blade body 10 at the first end 34 is greater than the thickness at the second end 36 .

The opening 28 is configured to first expand and then shrink from the cavity front edge 30 to the cavity trailing edge 32 in the transverse direction of the turbine blade. Expand and then contract, and contract towards the center of the bottom. In the illustrated embodiment, the bottom of the concave cavity 26 is designed to have a downward concave arc surface 38 . The advantage of this design is that when the air flow is leaked to the blade tip 12 by the centrifugal force, when passing through the concave cavity 26, the air flow will rapidly diffuse in the cavity due to the change of the structural cross-sectional area to form a vortex. The existence of the vortex makes the gas flow velocity slow and hinders the new Leakage of the working medium from the airflow improves the efficiency.

The opening 28 is similar in shape to the tip plane 20 . The opening 28 transitions smoothly from the cavity trailing edge 32 toward the turbine blade side to the cavity leading edge 30, and the angle of curvature increases gradually. The width of the opening 28 at the cavity front edge 30 is greater than that at the cavity trailing edge 32. width. Wherein, the cavity leading edge 30 is located close to the blade tip leading edge 22 , and the cavity trailing edge 32 is located in the middle of the blade tip plane 20 in the transverse direction.

The portion of the concave cavity 26 along the cross-section of the turbine blade is formed by several arcs. Specifically, in the illustrated embodiment, the portion of the concave cavity 26 along the cross-section of the turbine blade consists of eight arcs, including a first arc 40 at the leading edge 30 of the cavity, from The first arc 40 extends to both sides of the second arc 42, the third arc 44, the fourth arc 46, the fifth arc 48, the sixth arc 50, and the seventh arc Line 52 and the eighth arc 54 located at the rear edge 32 of the cavity. The way for the working fluid to leak from the blade tip 12 is from the leading edge 22 of the blade tip into the concave cavity 26, through the concave cavity 26 in the cavity close to the leading edge 30 of the concave cavity, which is a process of section expansion, and then through the concave cavity Cavity 26 is in the cavity near the rear edge 32 of the cavity, which is a process of cross-sectional contraction. The purpose of the section change is to make the air flow form a vortex, thereby reducing the leakage of the air flow, and finally flow out through the cavity trailing edge 32 to the blade tip trailing edge 24 .

In the process of the working fluid passing through the concave cavity 26, the function of the cavity segment formed by the first arc 40 is to rectify; the cavity segment formed by the second arc 42 and the third arc 44 is to form the eddy current Important cavity segment; the main function of the cavity segment formed by the fourth segment arc 46 and the fifth segment arc 48 is to develop the influence of the vortex; the sixth segment arc 50, the seventh segment arc 52 and the eighth segment arc The cavity segment formed by segment arc 54 mainly plays the role of gentle rectification. Since the concave cavity 26 changes not only in the direction of the cross section, but also in the direction of the longitudinal section, the formed vortex can fully develop in the entire concave cavity 26, which is beneficial to reduce the amount of fluid leakage.

Please continue to refer to Figures 3-5, the turbine blade of the present invention has a stacking shaft 56, the height of the concave cavity 26 in the longitudinal direction of the turbine blade is set to 8.865mm, and the distance between the bottom of the concave cavity 26 and the stacking shaft 26 is set The distance between the end of the blade edge plate 14 and the stacking axis is set at 9.7 mm. The point span of the leading edge 30 of the cavity is 156 degrees and the point span of the trailing edge of the cavity is 183 degrees. It should be understood that the above parameter values are specific settings and may be modified according to actual conditions.

The design of the streamlined concave cavity on the turbine blade of the present invention has its unique features no matter from the perspective of structural mechanics, or from the perspective of flow field, life and vibration mechanism. It solves the problem of excessive tip loss and low turbine efficiency caused by the excessive centrifugal force of the traditional turbine blade and the diffusion and flow of the working medium to the tip; it solves the difficulty in adjusting the natural frequency of the blade in the prior art and avoids interference with other parts of the whole machine The problem of resonance at the critical speed occurs; the problem of low yield and difficult processing in porous hollow blades is solved. The above analysis shows that the turbine blade with streamlined concave cavity of the present invention has many advantages of saving manufacturing materials, improving turbine efficiency, reliable and stable operation, and long life.

To sum up, the present invention proposes a new type of turbine blade. By designing a blade tip streamline concave cavity, the advantages of the turbine blade working in a high temperature, high speed, and high pressure environment are as follows:

(1) The design of the blade tip streamline concave cavity makes the whole blade lighter, avoids the concentration of thermal stress in the environment of high temperature, high speed and high pressure, and makes the temperature field change uniform, thereby improving the life of the entire turbine blade.

(2) In a high-speed environment, the working fluid of the gas turbine will be thrown towards the tip of the blade under the action of centrifugal force, resulting in part of the fluid working fluid leaking from the gap between the tip of the blade and the stator component without doing work, resulting in a loss of turbine efficiency. decline. The design of the blade tip streamline concave cavity makes the gap between the turbine blade and the stator part form an expansion cavity, and the fluid passing through here will produce a step vortex effect, where the energy of the leaked fluid is weakened and the speed becomes slower, and then Reduce the leakage of working medium, thereby improving efficiency.

(3) The design of the streamline concave cavity at the blade tip also plays a role in frequency modulation. Each blade has its own natural vibration frequency when it rotates. Through the design of the depth and size of the streamline concave cavity at the blade tip, it can be effectively avoided. Resonance occurs in rotating parts such as turbine disks and shafts, thereby increasing the life of the unit.

The concepts described herein may be implemented in other forms without departing from their spirit and characteristics. The particular embodiments disclosed are to be considered as illustrative rather than restrictive. Accordingly, the scope of the invention is to be determined by the appended claims rather than by these preceding descriptions. Any change within the literal meaning of the claims and within the range of equivalency shall belong to the scope of these claims.

Claims (10)

1. a kind of turbo blade, including leaf body, there is the leaf body blade tip and blade root, the blade tip to have on the top of the leaf body There is blade tip plane, which is characterized in that a concave shaped cavity is equipped in the turbo blade, the concave shaped cavity is streamlined, the spill There is chamber an opening, the opening to be located in the blade tip plane.

2. turbo blade as described in claim 1, which is characterized in that the blade tip plane have blade tip leading edge and with the leaf The opposite blade tip rear of sharp leading edge, the opening have close to the up-front cavity leading edge of the blade tip and close to the blade tip rear Cavity rear, the opening is configured to first expand to cavity rear from the cavity leading edge in the transverse direction of the turbo blade It shrinks again, the concave shaped cavity is configured to first expand to the bottom of the concave shaped cavity from the opening on the longitudinal direction of the turbo blade It opens and shrinks again, and the central reduction of the past bottom.

3. turbo blade as claimed in claim 2, which is characterized in that the concave shaped cavity is along the cross section of the turbo blade Part is made of several sections of camber lines.

4. turbo blade as claimed in claim 3, which is characterized in that the concave shaped cavity is along the cross section of the turbo blade Part is made of eight sections of camber lines, including is located at the up-front first segment camber line of the cavity, is prolonged from the first segment camber line to both sides The second segment camber line stretched, third section camber line, the 4th section of camber line, the 5th section of camber line, the 6th section of camber line, the 7th section of camber line and it is located at institute State the 8th section of camber line of cavity rear.

5. turbo blade as claimed in claim 4, which is characterized in that the chamber section that the first segment camber line is constituted is for whole Stream.

6. turbo blade as claimed in claim 4, which is characterized in that the second segment camber line and third section camber line were constituted Chamber section is used to form vortex.

7. turbo blade as claimed in claim 4, which is characterized in that the 4th section of camber line and the 5th section of camber line were constituted Chamber section is used to develop the influence being vortexed.

8. turbo blade as claimed in claim 4, which is characterized in that the 6th section of camber line, the 7th section of camber line and the 8th section The chamber section that camber line is constituted is used for gentle rectification.

9. turbo blade as claimed in claim 4, which is characterized in that the bottom of the concave shaped cavity has one to the recessed of lower recess Cambered surface.

10. turbo blade as claimed in claim 9, which is characterized in that connect a listrium, the turbo blade on the blade root With a long-pending folded axle, the concave shaped cavity the longitudinal height of the turbo blade be 8.865mm, the bottom of the concave shaped cavity with The distance of the long-pending folded axle is 5.16mm, and the end of the listrium is 9.7mm, the cavity leading edge at a distance from the long-pending folded axle Point span be 156 degree, the point span of the cavity rear is 183 degree.