JPH10196303A - High performance blade - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high performance blade to further improve efficiency through reduction of winding up of a secondary flow, in a high performance blade used as the moving blades or the stationary blades of a steam turbine and a gas turbine. SOLUTION: The shape in the direction of the height of a blade of a blade inlet part 2 is formed such that the central part of the height of the blade is protruded toward the belly 4 side of a blade 1, and formed in a curved shape forming a bow shape in a radial direction. Further, the shape, in the direction of the height of a blade, of a blade outlet part 6 is formed such that the central part, in the direction of the height of a blade, of the blade is formed in a curve shape, forming a bow shape, protruding toward the back side 5 of the blade 1 to form a blade profile. This constitution generates a flow, running toward a tip wall surface and a base wall surface, at the blade inlet part 2, pressurizes each wall surface, suppresses development of a vortex due to a secondary flow and reduces incurring of a secondary flow loss, and suppresses a pressure gradient in the direction of the height of the blade, occurring at the blade inlet port part 2, at the blade outlet port part 6, reduces the occurrence of winding up of a secondary flow due to a pressure gradient, reduces incurring of a flow loss due to a secondary flow, and improves the efficiency of a turbine.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a secondary flow generated on a side wall disposed near a blade operating in a uniform flow, and in a boundary layer developed on the blade. Control
To reduce secondary flow loss and improve internal efficiency,
Three-dimensionally changed shape three-dimensional blade, steam turbine,
Also, the present invention relates to a high-performance blade used as a moving blade and / or a stationary blade of a gas turbine or the like.

[0002]

2. Description of the Related Art In a high-performance reaction blade, a secondary flow loss is reduced by a three-dimensional design method for both a moving blade and a stationary blade by reaction control. However, in the conventional wing manufacturing by the three-dimensional design method, a secondary flow occurs in a boundary layer that develops on the side wall surface of the wing, on the side wall surface close to the tip and the base at the outer diameter end, and this is generated. It flowed out as a vortex from the trailing edge of the wing, causing secondary flow losses. However, more recently, by tilting the wing's height profile from the radial line, the flow is forced against the side wall surface, suppressing the development of vortices on the side wall surface close to the tip and base, and from the trailing edge of the wing. The one that reduces the outflow vortex to reduce the secondary flow loss has been put to practical use. Such a high-performance wing in which the shape of the wing in the height direction is inclined from the radial direction is usually called a complete three-dimensional wing.

FIG. 3 is a view of the above-described high-performance blade manufactured by the conventional three-dimensional design method viewed from the axial downstream side, and shows the shape of the blade trailing edge 02 and the flow flowing out of the blade 01. 05,06
FIG. As can be understood from the shape of the wing trailing edge 02 shown in the figure, a high-performance wing in which the wing height direction is linearly formed in the radial direction R is provided by a three-dimensional design method. By making the wing 01 shape,
Although the loss due to the secondary flow and the like generated in the boundary layer developed on the wing surface can be reduced, the tip wall surface 03 and the base wall surface 0 of the wing 01 which are arranged to face the outer diameter end.
4 cannot be reduced, and the secondary flow loss caused by the secondary flow and flowing out as a vortex from the wing trailing edge 02 cannot be reduced. could not.

[0004] For this reason, FIGS. 4 and 4 show the shape of the trailing edge 02 ′ and the flows 05 and 011 flowing out from the inside of the blade 01 ′ when the high-performance blade is viewed from the downstream side in the axial direction. As shown in FIG. 5 which is a perspective view of the high-performance wing, and FIG. 6 which is a perspective view of the high-performance wing arranged between the chip wall surface 03 and the base wall surface 04, the blade height direction is the radial direction R. In the vicinity of the tip surface 03 and the base surface 04, the shape in the blade height direction is inclined in opposite directions to each other, and a continuous arcuate curve is formed in the blade height direction. High performance wings, referred to as wings, are being manufactured and used.

[0005] This type of high-performance wing is sometimes referred to as a skewed wing or a bow wing. Furthermore, in such a complete three-dimensional wing,
As shown in FIGS. 5 and 6, the arcuate curvature provided in the height direction of the wing 02 with respect to the radial direction R indicates both the wing inlet portion 07 near the leading edge and the wing outlet portion 08 near the trailing edge 02 ′. It is formed so that the central portion in the blade height direction has a maximum protrusion amount and is curved toward the blade antinode 09 side. That is, as shown in FIG. 5, the abdominal side 0 from the leading edge to the trailing edge 02 'by an amount indicated by the arrow length in the blade height direction with respect to the radial direction R.
In addition, the tip side and the base side, which are inclined to the radial direction R and are inclined to each other at an angle of 10, are connected by a smooth curve to form a bow.

In such a conventional complete tertiary wing, the central portion of the wing height is curved in an arcuate manner toward the ventral side 09, so that the dorsal side 010 near the chip wall surface 03 and the base wall surface 04 has the configuration shown in FIG. These wall surfaces 03 and 04 as shown by arrows
Are generated by increasing the pressures on the chip wall surface 03 and the base wall surface 04, and reducing the cross-flow that develops on the wall surfaces 03 and 04 and occurs in the boundary layer. The next flow loss can be reduced.

However, as described above, the chip wall surface 0
Increasing the pressure near the wall 3 and the base wall surface 04 causes a pressure gradient in the blade height direction, so-called radial direction R, from the vicinity of the wall surfaces 03 and 04. The winding of the secondary flow in the radial direction R, which is generated in the boundary layer, increases, and the winding of the secondary flow disturbs the flow of the main flow 05 passing through the wing 01 ′,
There is a problem that the flow loss is increased and the paragraph efficiency is reduced.

[0008]

SUMMARY OF THE INVENTION The present invention increases the pressure near the conventional high-performance blades, especially the chip wall and the base wall, and reduces the cross flow generated in the boundary layer developed on these walls. In addition to maintaining the characteristics of the conventional complete three-dimensional wing, which reduces the secondary flow loss, the blade height from the tip wall surface and the base wall surface generated by the conventional complete three-dimensional wing is maintained. In order to prevent a decrease in efficiency due to the winding of the secondary flow generated by the pressure gradient formed in the vertical direction, at the blade outlet,
A high-performance blade that reduces the reduction in paragraph efficiency by suppressing the magnitude of the pressure gradient formed from the tip wall surface and the base wall toward the center of the blade height to reduce winding of the secondary flow. The task is to provide

[0009]

Therefore, the high-performance blade of the present invention has the following means. By the three-dimensional design method, the pressure near the tip wall located near the tip of the blade that operates in a uniform flow and the pressure near the base wall located near the base of the blade are increased, and these wall surfaces are increased. In a high-performance wing made of a complete three-dimensional wing that reduces the cross flow in the boundary layer developed above and reduces the secondary flow loss, the wing profile is set at the wing height center The wings were curved in the abdominal side at the wing portion, and the wing outlet portion was formed into the wing shape curved in the back side at the center of the wing height.

[0010] The high-performance wing of the present invention has the following features.
As in the case of the conventional complete three-dimensional wing, the arc-shaped curvature of the wing entrance to the ventral side reduces the secondary flow in the boundary layer between the tip and the base wall surface and the base wall surface and the wing surface at the wing inner and outer diameter ends. The development of the vortex generated from the surface can be suppressed, and the strength of the vortex flowing out from the trailing edge of the wing can be reduced, so that the secondary flow loss can be reduced.

In addition, in addition to the above, since the blade outlet has an arcuate curve projecting to the back side opposite to the arcuate curve of the blade inlet, the flow is pressed against the wall surface at the blade inlet. The pressure gradient in the radial direction, which had decreased from the tip wall surface and the base wall surface toward the center of the blade height, gradually decreased from the blade inlet to the blade outlet, and the secondary flow at the blade back surface It reduces curling in the radial direction and reduces secondary flow loss, reducing the turbulence of the main flow passing through the inside of the wing, which occurs with conventional complete three-dimensional wings, and improving paragraph efficiency. Can be.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a high-performance blade according to the present invention will be described below with reference to the drawings. FIG. 1 is a view showing a first embodiment of the high-performance wing of the present invention, and is a perspective view showing an arcuate curved shape provided in the wing height direction. FIG. 2 is a view showing the high-performance wing shown in FIG. It is a perspective view for showing what was arranged between a chip wall surface and a base wall surface.

As shown in FIG. 1, at the wing inlet portion 2 of the wing 1, the amount of protrusion from the tip side and the base side to the antinode 4 side is gradually increased, so that the antinode 4 side is located at the center of the wing height. The most protruding curved arcuate shape is formed in the blade height direction. That is, at the leading edge 3, which is the most upstream end of the wing inlet section 2, an arc-shaped curve protruding from the radial direction R in the antinode 4 direction as viewed in the direction of the arrow by the length shown in the direction of the arrow is formed. Have been.

At the blade outlet 6 of the blade 1, the amount of protrusion from the tip side and the base side to the back side 5 is gradually increased, and a curved arcuate shape having the maximum amount of protrusion at the center of the blade height. Is formed. That is, at the trailing edge 7, which is the most downstream end of the blade outlet portion 6, an arc-shaped curve protruding from the radial direction R in the five dorsal directions as viewed in the direction of the arrow by the length shown in the arrow direction. Is formed. Also, these bow-shaped curves provided in the blade height direction are connected in a smooth curve without any discontinuity even from the blade inlet portion 2 to the blade outlet portion 6.

Since the high-performance blade of the present invention is configured as described above, the blade-shaped bend provided in the radial direction of the blade inlet 2 causes the blade 1 shown in FIG. A flow similar to the pressing flow 011 shown in FIG. 4 is generated toward the chip wall surface 8 provided on the tip side of the wing 1 and the base wall surface 9 provided on the base side of the wing 1.
The pressure on the upper surface and the base wall 9 is increased, and the secondary flow in the boundary layer that develops on the wall surfaces 8 and 9 is reduced by these pressure increases, and the vortex generated from each of the wall surfaces 8 and 9 is developed. , The strength of the vortex flowing out from the trailing edge 7 of the blade 1 can be reduced, and the secondary flow loss can be reduced as in the case of the conventional complete tertiary blade.

Further, since the blade outlet portion 6 has an arc-shaped curve having a convex surface on the back side 5 opposite to the arc-shaped curve formed at the blade inlet portion 2, the blade inlet portion 2 has: The flow is pressed against the tip wall surface 8 and the base wall surface 9 and a pressure drop occurs from the tip wall surface 8 and the base wall surface 9 toward the center of the blade height. Due to the change in the shape of the bow from the wing inlet portion 2 to the wing outlet portion 6 which changes from the shape to an arcuate shape protruding to the back side, the size gradually decreases, and is completely eliminated at the wing outlet portion 6. Due to the disappearance of the pressure gradient decreasing from the tip wall surface 8 and the base wall surface 9 toward the center of the blade height, the radius of the secondary flow at the back surface of the blade 1, which is generated in the conventional complete three-dimensional blade, The winding in the direction is reduced, the secondary flow loss is reduced, and the disturbance of commutation passing through the inside of the wing, which occurred in the conventional complete three-dimensional wing, is reduced, and the paragraph efficiency can be improved. it can.

[0017]

As described above, according to the high-performance wing according to the present invention, a complete three-dimensional wing which is improved from the high-performance wing manufactured by the conventional three-dimensional design method by the configuration shown in the claims. In comparison with the above, the generation of pressure gradients that change in the blade height direction from the tip wall surface and the base wall surface, respectively, is suppressed, and consequently, secondary winding in the radial direction is also suppressed. The resulting flow loss is greatly reduced and turbine efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a view showing a first embodiment of a high-performance blade of the present invention, and is a perspective view showing an arcuate curved shape provided in a blade height direction;

FIG. 2 is a perspective view showing the high-performance wing shown in FIG. 1 arranged between a chip wall surface and a base wall surface;

FIG. 3 is a view of a high-performance blade manufactured by a conventional three-dimensional design method viewed from an axial wake side, and is a conceptual diagram showing a shape of a blade trailing edge and a flow flowing out of the blade;

FIG. 4 is a view of the conventional complete three-dimensional wing in which the high-performance wing shown in FIG. 3 is improved, viewed from the downstream side in the axial direction, and is a conceptual diagram showing the shape of the trailing edge of the wing and the flow flowing out of the wing;

5 is a perspective view of the complete three-dimensional wing shown in FIG. 4,

FIG. 6 is a partial perspective view in which the complete three-dimensional wing shown in FIG. 5 is arranged between a chip wall surface and a base wall surface.

[Description of Signs] 1 wing 2 wing entrance 3 leading edge 4 (wing) belly 5 (wing) back 6 wing outlet 7 trailing edge 8 tip wall 9 base wall

Claims (1)

[Claims] 1. A high-performance blade used as a moving blade and a stationary blade of a steam turbine or a gas turbine,
The wing inlet section is formed in an arcuate curved shape with the wing height central part protruding to the ventral side, and the wing outlet part is formed in the arcuate curved shape with the wing height central part protruding to the back side. High performance wing characterized by being formed in.