CN114075997B

CN114075997B - Special-shaped turbine blade

Info

Publication number: CN114075997B
Application number: CN202010841952.1A
Authority: CN
Inventors: 曹建礼
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-08-20
Filing date: 2020-08-20
Publication date: 2024-05-31
Anticipated expiration: 2040-08-20
Also published as: CN114075997A

Abstract

The invention relates to the technical field of fluid flow and fluid driving, in particular to a special-shaped turbine blade, which comprises a blade body, wherein the blade body comprises a blade body, the bottom of the blade body is arc-shaped, and an arc-shaped bottom edge is formed; the bottoms of the left side and the right side of the sheet body form a left vertical bottom surface and a right vertical bottom surface; the upper part of the left side of the sheet body is a concave left arc surface; the upper part of the right side of the sheet body is a right convex arc-shaped surface which protrudes outwards; the top end of the sheet body is a first arc-shaped surface; the bottom arc length of the lengthened blade is adopted to form a lengthened paraxial part and a shortened distal part at the top is arranged; the novel blade has the advantages of being simple in structure, capable of improving the compression resistance of the blade, improving the thrust-weight ratio of the blade and the like through integrated forming processing.

Description

Special-shaped turbine blade

Technical Field

The invention relates to the technical field of fluid flow and fluid driving, in particular to a special-shaped turbine blade.

Background

The turbine has two functions, one turbine rotating to drive fluid flow through the turbine blades. The other is that fluid flow through the turbine blades drives the turbine in rotation. The critical component of these two turbines is therefore the blade, the efficiency being closely related to the geometry of the blade.

Turbine blades are an important component of a turbine section in a gas turbine engine. The high-speed rotating blades are responsible for pressing the high-temperature and high-pressure air flow into the burner to maintain the operation of the engine. In order to ensure stable long-term operation under extreme environments of high temperature and high pressure, turbine blades are often forged from high temperature alloys and cooled in different ways, such as internal air flow cooling, boundary layer cooling, or thermal barrier coatings for protecting the blades, to ensure operational reliability. In steam turbine engines and gas turbine engines, metal fatigue of the blades is the leading cause of engine failure. Strong vibration or resonance may cause metal fatigue. Engineers often employ friction dampers to reduce damage to the blade from these factors.

Because the curved configuration of the engine blades is extremely complex and yet imparts considerable torque and extremely high combustion temperatures, the materials of the blades are typically selected to be high temperature and high strength materials. Modern turbine blades are usually manufactured from directionally solidified monocrystalline materials, and air-cooled channels are also opened up internally, that is to say the blades are hollow. The blade with complex shape must be a piece of crystal to improve the performance at high temperature and to have absolute high precision.

For a long time, turbine blades have a common characteristic from domestic electric fans to gas turbines, namely that the near axis position is relatively narrow to the far axis position.

Turbine blades of this type may be used in conditions where the fluid pressure is not too high. But under conditions where the fluid is required to have a certain pressure.

Because the rotational linear velocity of the proximal portion is slower than the rotational linear velocity of the distal portion of the turbine blade, plus the relative narrowing of the proximal portion of the blade, the fluid flow and fluid pressure at which the proximal portion of the blade is driven is less than the fluid flow and fluid pressure at which the distal portion of the blade is driven.

Thus, a vertical fluid is formed on the working surfaces on the front side and the back side of the turbine; the vertical fluid pressure difference in the main flow direction forms a vortex and noise as shown in fig. 1. If the fluid pressure rises further, a portion of the fluid driven by the distal portion of the blade returns to the side of the turbine wheel entering the fluid through the proximal portion of the blade due to this vertical pressure differential, as shown in FIG. 2.

In the prior art, in order to increase the flow rate of a paraxial region of a turbine blade, a blade angle of the paraxial region of the blade is changed to increase the flow rate of driving fluid. In practice, the pressure of the driving fluid at the proximal part of the blade cannot be increased. This problem is not well solved and all gas turbines and high pressure turbines have problems of relatively low efficiency and excessive noise.

Disclosure of Invention

Aiming at the defects and shortcomings of the prior art, the invention provides the special-shaped turbine blade which is more scientific and reasonable in design, high in efficiency, low in noise, low in vibration, high in safety system and long in service life, can improve the overall performance and efficiency of the turbine, the propeller, the water pump, the steam turbine and other fluid machinery, and is more environment-friendly.

The invention relates to a special-shaped turbine blade, which comprises a blade body, wherein the blade body comprises a sheet body, and the bottom of the sheet body is arc-shaped to form an arc-shaped bottom edge end LM; the bottoms of the left side and the right side of the sheet body form a left vertical bottom face JL and a right vertical bottom face KM; the upper part of the left side of the sheet body is provided with a concave left arc-shaped surface JF; the upper part of the right side of the sheet body is a right convex arc-shaped surface KD which protrudes outwards; the top end of the sheet body is a first arc-shaped surface FD; the second arc-shaped surface JCKMGL of the sheet body is a paraxial part; the third cambered surface FADIBH of the sheet body is a far axis part; the thrust of the fluid at the proximal shaft section is relatively balanced with the thrust of the fluid at the distal shaft section.

Further, the left vertical bottom surface JL and the right vertical bottom surface KM are in a parallel structural relationship.

Further, the arcuate bottom end LGM of the blade mates with the outer contour of the turbine hub.

The invention has the beneficial effects that: the invention relates to a special-shaped turbine blade, which adopts the arc length at the bottom of a lengthened blade to form a lengthened paraxial part and a shortened distal part at the top; the novel blade has the advantages of being simple in structure, capable of improving the compression resistance of the blade, improving the thrust-weight ratio of the blade and the like through integrated forming processing. .

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate and together with the description serve to explain the application, if necessary:

FIG. 1 is a state diagram of a turbine blade in the background of the invention at low fluid pressure;

FIG. 2 is a state diagram of a turbine blade in the background of the invention when fluid pressure is high;

FIG. 3 is a schematic diagram of the structure of the present invention;

FIG. 4 is a schematic view of the present invention disposed on a turbine hub.

Detailed Description

The present invention will now be described in detail with reference to the drawings and the specific embodiments thereof, wherein the exemplary embodiments and the description are for the purpose of illustrating the invention only and are not to be construed as limiting the invention.

As shown in fig. 3-4, the special-shaped turbine blade according to the present embodiment includes a blade body, where the blade body includes a blade body, and the bottom of the blade body is in a circular arc shape, so as to form an arc-shaped bottom edge LM; the bottoms of the left side and the right side of the sheet body form a left vertical bottom face JL and a right vertical bottom face KM; the upper part of the left side of the sheet body is provided with a concave left arc-shaped surface JF; the upper part of the right side of the sheet body is a right convex arc-shaped surface KD which protrudes outwards; the top end of the sheet is a first arcuate surface FD.

Further, the second arcuate surface JCKMGL of the blade is proximal.

Further, the third cambered surface FADIBH of the sheet body is a distal shaft portion.

The working principle of the invention is as follows:

In the design, the bottom of the sheet body is arc-shaped, and an arc-shaped bottom edge end from a twelfth point to a thirteenth point is formed;

the bottoms of the left side and the right side of the sheet body form a left vertical bottom surface from a tenth point to a twelfth point and a right vertical bottom surface from an eleventh point to a thirteenth point;

the upper part of the left side of the sheet body is a left concave arc surface which forms an arc surface between a tenth point and a sixth point of the concave;

the upper part of the right side of the sheet body is a right convex arc-shaped surface which forms an arc surface between a fourth point and an eleventh point which are outwards protruded;

The top end of the sheet body is a first arc-shaped surface of the arc surface between the sixth point and the fourth point;

A second arc surface of an arc area formed by a tenth point, a third point, a tenth point, a thirteenth point, a seventh point and a twelfth point of the sheet body is a paraxial part;

A third cambered surface of the cambered area formed by the sixth point, the first point, the fourth point, the ninth point, the second point and the eighth point of the sheet body is a far-axis part;

the thrust of the fluid on the proximal shaft part is relatively balanced with the thrust of the fluid on the distal shaft part;

Wherein: the point A is the first point, the point B is the second point, the point C is the third point, the point D is the fourth point, the point E is the fifth point, the point F is the sixth point, the point G is the seventh point, the point H is the eighth point, the point I is the ninth point, the point J is the tenth point, the point K is the tenth point, the point L is the twelfth point, and the point M is the thirteenth point.

The blade body is uniformly arranged around the outer surface of the turbine hub, the turbine hub is circular in shape, the impeller shaft is arranged in the center of the turbine hub, and the impeller shaft and the turbine hub are of a concentric circle structure.

In the design, a vertical straight line I upwards of the axis O of the impeller shaft intersects with the sheet body, the vertical straight line I intersects with the bottom of the sheet body at a point G and intersects with the top of the sheet body at a point A; the arc bottom edge LM (arc bottom edge LGM) is parallel to the arc JCK, and the point C is the intersection point of the vertical straight line l and the arc JCK; arcuate surface JCKMGL forms a paraxial region.

In the design, the straight line midpoint between the point F and the point J on the left side surface of the sheet body is the point E, the middle part of the right convex arc-shaped surface KD of the right side surface of the sheet body is the point I, the intersection point of the arc EBI and the left concave arc-shaped surface JF is the point H, the curved surface formed by the arc HBI and the arc-shaped surface FAD is the arc-shaped surface FADIBH, and the arc-shaped surface FADIBH is the far axis part.

In this design, the camber FD/camber lm=og/OA.

In this design, CG: ag=1: 4 to 5.

In this design, ab=ac/2.

In this design, JL AO KM.

In this design, arc hi= (arc fd+arc LM)/2.

In this design, ea= (0.08 to 0.1)/AC.

The present invention differs from conventional turbine blades in that the turbine hub and impeller shaft are identical to those on conventional equipment in this design. The design is changed from the traditional method of changing the blade angle to increase the driving length and area of the blade paraxial region only at the paraxial region of the turbine blade, as shown in fig. 3.

The driving length of the blade is required to be larger than that of the far shaft part, and the arc length corresponding to the corresponding angle allocated by the single turbine blade is required. For a blade driving fluid, the fluid inlet of the turbine, the proximal portion of the blade is flush with the distal portion, the turbine fluid outlet, the proximal portion of the blade is retarded, and prolonged. The blade distal shaft portion is advanced in phase. The ratio line between the inner diameter and the outer diameter of the blade changes along with the change of the ratio of the diameter to the arc length of the turbine, and is shown in figure 4.

Practice proves that the impeller blades can improve the flow and pressure of the whole turbine by 20% -48%, and can reduce noise.

The invention relates to a special-shaped turbine blade, which adopts the arc length at the bottom of a lengthened blade to form a lengthened paraxial part and a shortened distal part at the top; the novel blade has the advantages of being simple in structure, capable of improving the compression resistance of the blade, improving the thrust-weight ratio of the blade and the like through integrated forming processing.

The foregoing description is only of the preferred embodiments of the invention, and all changes and modifications that come within the meaning and range of equivalency of the features and concepts described herein are therefore intended to be embraced therein.

Claims

1. A profiled turbine blade, characterized in that: the blade comprises a blade body, wherein the blade body comprises a blade body, the bottom of the blade body is arc-shaped, and an arc-shaped bottom edge from a twelfth point (L) to an arc-shaped edge of a thirteenth point (M) is formed;

The bottoms of the left side and the right side of the sheet body form a left vertical bottom surface from a tenth point (J) to a twelfth point (L) and a right vertical bottom surface from an eleventh point (K) to a thirteenth point (M);

The upper part of the left side of the sheet body is a left concave arc surface which forms an arc surface between a tenth point (J) and a sixth point (F) of the concave; the upper part of the right side of the sheet body is a right convex arc-shaped surface which forms an arc surface between a fourth point (D) and an eleventh point (K) which are outwards protruded; the top end of the sheet body is a first arc-shaped surface of an arc surface between a sixth point (F) and a fourth point (D);

A second arc surface of an arc-shaped area formed by a tenth point (J), a third point (C), an eleventh point (K), a thirteenth point (M), a seventh point (G) and a twelfth point (L) of the sheet body is a paraxial part; a third cambered surface of the cambered area formed by the sixth point (F), the first point (A), the fourth point (D), the ninth point (I), the second point (B) and the eighth point (H) of the sheet body is a far-axis part; the thrust of the fluid on the proximal shaft part is relatively balanced with the thrust of the fluid on the distal shaft part;

An arc intersection point between a vertical straight line L with the axis O of the impeller shaft upwards and a twelfth point (L) and a thirteenth point (M) is a seventh point (G); an arc intersection point between the vertical straight line l and the tenth point (J) and the eleventh point (K) is a third point (C); an arc intersection point between the vertical straight line l and the eighth point (H) and the ninth point (I) is a second point (B); an arc intersection point between the vertical straight line l and the sixth point (F) and the fourth point (D) is a first point (A); the midpoint of the arc between the sixth point (F) and the tenth point (J) is an eighth point (H); a midpoint of a vertical line between the sixth point (F) and the tenth point (J) is a fifth point (E); the midpoint of the arc between the fourth point (D) and the eleventh point (K) is a ninth point (I);

The turbine blade paraxial region is changed into a region for increasing the driving length and the driving area of the blade paraxial region by a traditional method for changing the blade angle; the driving length of the turbine blade is required to be longer than the arc length corresponding to the corresponding angle distributed by the single turbine blade at the far shaft part; for a blade driving fluid, a fluid inlet of the turbine, a proximal shaft part of the blade is leveled with a distal shaft part, a fluid outlet of the turbine, the proximal shaft part of the blade is lagged and prolonged; the position of the blade far shaft part is advanced; the ratio line between the inner and outer diameters of the blades changes as the ratio of turbine diameter to arc length changes.

2. A profiled turbine blade according to claim 1, characterized in that: the left vertical bottom surface and the right vertical bottom surface are in parallel structural relationship.

3. A profiled turbine blade according to claim 1, characterized in that: the arc bottom edge end of the sheet body is matched with the outer contour of the turbine hub.