CN114075997A

CN114075997A - Special-shaped worm wheel blade

Info

Publication number: CN114075997A
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: 2022-02-22
Anticipated expiration: 2040-08-20
Also published as: CN114075997B

Abstract

The invention relates to the technical field of fluid flow and fluid drive, in particular to a special-shaped worm wheel blade, which comprises a blade body, wherein the blade body comprises a sheet body, the bottom of the sheet body is arc-shaped, and an arc-shaped bottom edge end LM is formed; the bottoms of the left and right sides of the sheet body form a left vertical bottom surface JL and a right vertical bottom surface KM; the upper part of the left side of the sheet body is an inwards 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 an arc surface FD; the arc length of the bottom of each blade is lengthened to form a lengthened paraxial part and a shortened paraxial part arranged at the top; the novel blade has the advantages of simple structure, integrated forming and processing, capability of improving the pressure resistance of the blade, improvement of the thrust-weight ratio of the blade and the like.

Description

Special-shaped worm wheel blade

Technical Field

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

Background

The turbine has two functions, one in that rotation of the turbine drives fluid flow through the turbine blades. The other is that the fluid flow drives the turbine wheel to rotate through the turbine blades. The key component of both turbines is therefore the blades, the efficiency and geometry of which are closely related.

Turbine blades are important components of the turbine section of a gas turbine engine. The blades rotating at high speed are responsible for drawing high-temperature and high-pressure airflow into the combustor to maintain the operation of the engine. In order to ensure stable and long-term operation in extreme environments of high temperature and high pressure, turbine blades are often forged from high temperature alloys and are cooled in different ways, such as internal air flow cooling, boundary layer cooling, or thermal barrier coatings 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 can lead to metal fatigue. Engineers often use friction dampers to reduce the damage these factors cause to the blades.

Because the engine blades have extremely complex curved surface configurations and need to transmit considerable torque and extremely high combustion temperature, the materials of the blades are generally selected from high-temperature-resistant and high-strength materials. Modern turbine blades are usually made of directionally solidified single crystal material and are also internally provided with air-cooled channels, i.e. the blades are hollow. Directional solidification is required during casting, and the complex blade must be a crystal to improve performance at high temperatures and have absolute height accuracy.

For a long time, the turbine blades from civil electric fans to gas turbines have a common feature, namely, the relative narrowness from the near-axis part to the far-axis part.

This type of turbine blade may be used in conditions where the fluid pressure is not too high. But require the fluid to have a certain pressure.

Because the rotating linear speed of the near-axis part is slower than that of the far-axis part of the turbine blade, and the near-axis part of the blade is relatively narrow, the fluid flow and the fluid pressure driven by the near-axis part of the blade are smaller than those driven by the far-axis part of the blade.

Thus, a vertical fluid is formed on the working surfaces of the front side and the back side of the turbine; the perpendicular fluid pressure in the main flow direction is different, resulting in turbulence 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 through the proximal portion of the blade to the side of the turbine into which the fluid flows due to the vertical pressure differential of the fluid, as shown in FIG. 2.

At present, in order to increase the flow rate of a turbine blade in a proximal portion of a turbine blade, a blade angle of the proximal portion of the blade is changed to increase the flow rate of a driving fluid in a turbine blade or a high-pressure turbine. In practice, the pressure of the driving fluid in the proximal portion of the blade cannot be increased. This problem is not well solved and all gas turbines and high pressure turbines suffer from relatively low efficiency and high noise.

Disclosure of Invention

The invention aims to provide a special-shaped worm wheel blade aiming at the defects and shortcomings of the prior art, the special-shaped worm wheel blade 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 fluid machinery such as a turbine, a propeller, a water pump and a steam turbine, and is more environment-friendly.

The invention relates to a special-shaped worm wheel blade which comprises a blade body, wherein the blade body comprises a sheet body, the bottom of the sheet body is arc-shaped, and an arc-shaped bottom edge end LM is formed; the bottoms of the left and right sides of the sheet body form a left vertical bottom surface JL and a right vertical bottom surface KM; the upper part of the left side of the sheet body is an inwards 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 an arc surface FD; the arc surface JCKMGL of the sheet body is a paraxial part; the cambered surface FADIBK of the sheet body is a far axis part; the thrust of the fluid at the near-axis part is relatively balanced with the thrust of the fluid at the far-axis part

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

Further, the arc-shaped bottom edge end LGM of the sheet body is matched with the outer contour of the turbine hub.

The invention has the beneficial effects that: the invention relates to a special-shaped worm wheel blade, which adopts the technical scheme that the arc length of the bottom of a lengthened blade is adopted to form a lengthened paraxial part and a shortened paraxial part arranged at the top; the novel blade has the advantages of simple structure, integrated forming and processing, capability of improving the pressure resistance of the blade, improvement of the thrust-weight ratio of the blade and the like.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, and are not to be considered limiting of the invention, in which:

FIG. 1 is a state diagram of a turbine blade according to the background of the invention at low fluid pressures;

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

FIG. 3 is a schematic structural view of the present invention;

FIG. 4 is a schematic view of the structure 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 specific embodiments, wherein the exemplary embodiments and descriptions are provided only for the purpose of illustrating the present invention and are not to be construed as limiting the present invention.

As shown in fig. 3 to 4, the profiled worm wheel blade according to the present embodiment includes a blade body, the blade body includes a sheet body, and a bottom of the sheet body is arc-shaped to form an arc-shaped bottom edge end LM; the bottoms of the left and right sides of the sheet body form a left vertical bottom surface JL and a right vertical bottom surface KM; the upper part of the left side of the sheet body is an inwards 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 an arc-shaped surface FD.

Furthermore, the arc surface JCKMGL of the sheet body is a paraxial part.

Furthermore, the cambered surface FADIBK of the sheet body is a far axis part.

The working principle of the invention is as follows:

the blade body is uniformly arranged on the periphery of the outer surface of the turbine hub, the turbine hub is circular, the center of the turbine hub is provided with the impeller shaft, and the impeller shaft and the turbine hub are of a concentric circle structure.

In the design, a vertical straight line l which is upward from the axis O of the impeller shaft intersects with the sheet body, the vertical straight line l 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 line JCK, and the point C is the intersection point of the vertical straight line l and the arc line JCK; the arcuate surface JCKMGL forms a proximal portion.

In this design, the straight line mid point that F point on the lamellar body left surface was some E with J, and the middle part of the right convex arc arcwall KD of lamellar body right flank is some I, and the nodical point that pitch arc EBI and left concave arcwall JF are some H for the curved surface that pitch arc HBI and arcwall FAD formed is cambered surface FADIBK, and cambered surface FADIBK is the distal axis position.

In this design, the arc FD/LM is OG/OA.

In the present design, CG: AG 1: 4 to 5.

In this design, AB is AC/2.

In this design, JL/AO/KM.

In this design, the arc HI is (arc FD + arc LM)/2

In the design, EA is (0.08-0.1)/AC.

The invention differs from the traditional turbine blade by the statement that in the design, the turbine hub and the impeller shaft are the same as those of the traditional equipment. The design is only that the blade near-axis part of the turbine blade is changed from the traditional method of changing the blade angle to increase the driving length and the driving area of the blade near-axis part, as shown in figure 3.

The driving length of the turbine blade is larger than the arc length corresponding to the corresponding angle distributed by the single turbine blade at the far shaft part. For the blade for driving the fluid, the fluid inlet of the turbine, the blade near-axis part and the far-axis part are level, and the fluid outlet of the turbine and the blade near-axis part are delayed and prolonged. The far-axis part of the blade is correspondingly advanced. The ratio line between the inner and outer diameters of the blade varies with the ratio of the turbine diameter to the arc length, as shown in figure 4.

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

The invention relates to a special-shaped worm wheel blade, which adopts the technical scheme that the arc length of the bottom of a lengthened blade is adopted to form a lengthened paraxial part and a shortened paraxial part arranged at the top; the novel blade has the advantages of simple structure, integrated forming and processing, capability of improving the pressure resistance of the blade, improvement of the thrust-weight ratio of the blade and the like.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention, and all equivalent changes and modifications made based on the features and principles described in the claims of the present invention are included in the scope of the present invention.

Claims

1. A special-shaped worm wheel blade is characterized in that: the blade comprises a blade body, wherein the blade body comprises a sheet body, the bottom of the sheet body is arc-shaped, and an arc-shaped bottom edge end LM is formed; the bottoms of the left and right sides of the sheet body form a left vertical bottom surface JL and a right vertical bottom surface KM; the upper part of the left side of the sheet body is an inwards 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 an arc surface FD; the arc surface JCKMGL of the sheet body is a paraxial part; the cambered surface FADIBK of the sheet body is a far axis part; the thrust of the fluid at the proximal shaft part is relatively balanced with the thrust of the fluid at the distal shaft part.

2. The profiled worm gear blade as recited in claim 1, wherein: the left vertical bottom surface JL and the right vertical bottom surface KM are in a parallel structure relationship.

3. The profiled worm gear blade as recited in claim 1, wherein: the arc bottom edge end LGM of lamellar body cooperatees with turbine wheel hub's outline.