KR101509384B1 - Sealing installation for blade tip of gas turbine - Google Patents

Abstract

Disclosed is a blade tip sealing apparatus of a gas turbine capable of minimizing a leakage loss of combustion gas and improve efficiency of an engine through a formation of blow seals in order to produce a countercurrent flow opposite to a main flow direction of the combustion gas in a gap part between a casing and blades of a turbine. The blade tip sealing apparatus comprises: the casing (22) guiding the flow of the combustion gas; a plurality of the blades (26) combined with a rotary shaft (20) inside the casing (22); a shroud (28) installed to cover the front end portions of the blades (26); a plurality of blow seals (30) along the entire circumference of the shroud (28); and a turning installation variably adjusting an inclination angle of the blow seals (30) in accordance with a rotational speed of the blades (26).

Description

Technical Field [0001] The present invention relates to a gas turbine,

The present invention relates to a blade tip sealing apparatus for a gas turbine, and more particularly to a blade tip sealing apparatus for a gas turbine, A blade tip sealing device of a gas turbine capable of reducing the risk of damage to the blade due to rubbing due to proper clearance between the casing and the blade of the turbine, .

Generally, a gas turbine device is a kind of a turbomachine that burns fuel using high-pressure compressed air and generates rotational power by using high-temperature / high-pressure combustion gas discharged in the course of combustion.

The gas turbine having such a structure includes a compressor that sucks outside air and compresses it to a high pressure, a combustor that mixes and combusts the air compressed at high pressure with the fuel, and a high-temperature / high-pressure combustion gas And a turbine that generates the rotational force needed to generate energy from the flow.

In addition, leakage of combustion gas directly to the outside of the turbine without passing through the blades has a considerable influence on the overall efficiency of the engine, so measures against this are very important. In one example, FIG. 1 shows a leakage loss region of a flow generated in a conventional gas turbine.

1, the turbine 71 includes a blade 75 rotating at a high speed with respect to the rotary shaft 73 via the flow of the combustion gas, and the leakage of the flow is transmitted to the free end of the blade 75 And the casing (77). That is, the flow of the combustion gas discharged after the combustion is largely divided into the main flow C discharged through the blade 75, the leakage flow D toward the gap between the blade 75 and the casing 77 Can be distinguished.

The shroud 79 located at the free end of the blade 75 is located on the outer side of the casing 77 so as to prevent the leakage of the combustion gas to the outside of the casing 77. In this case, since the leakage flow D of the combustion gas is a large factor in determining the efficiency of the engine, The labyrinth seal 81 protruding toward the inner circumferential surface is integrally formed. A honeycomb seal 83 is provided on the inner circumferential surface of the casing 77 to set a proper clearance with the labyrinth seal 81.

The installation state of the labyrinth seal 81 with respect to the blade 75 can be understood more clearly with reference to FIG. That is, the labyrinth seal 81 protrudes in a direction perpendicular to the outer surface of the shroud 79 to ensure a proper clearance with the honeycomb seal 83.

In the conventional turbine 71, a space secured in the space between the labyrinth seal 81 and the honeycomb seal 83 is formed by the shroud 79 including the blade 75 rotating at a high speed, In addition to the forward function of preventing the parts from being damaged by preventing direct contact between the honeycomb seals 83 of the casing 77 corresponding to the casing 77, excessive leakage of the combustion gas is caused when a gap of more than a proper level is set, It is possible to obtain a proper level of clearance, which is a very important factor in the design of the gas turbine. For example, if the gap is set too narrow, it may contribute to increase the efficiency of the engine by reducing the leakage loss in the initial operation of the gas turbine. However, rubbing due to thermal deformation between the rotor and the stator, Which may lead to damage to parts due to contact in extreme cases.

For example, in a squealer type blade 75 without the labyrinth seal 81, a leakage flow D is accompanied by a gap formed between the blade 75 and the casing 77, In the case of the blade 75 having the labyrinth seal 81, the leakage flow D generated in the gap with the casing 77 can be reduced, but the structural stability The problem is accompanied by limitations in terms of the life span of the parts.

That is, when one or more labyrinth seal 81 is formed on the free end of the blade 75 in the conventional turbine 71, the aerodynamic performance can be improved by reducing the leakage of the combustion gas. However, The problem of rigidity and durability accompanying the additional setting of the labyrinth seal 81 corresponding to the heavy material at the free end of the member rotating at high speed is offset by the expected effect of the improved aerodynamic performance It is necessary to cope with leakage of the combustion gas in other directions. Particularly, since the rebound flow accompanying the setting of the labyrinth seal 81 exhibits a flow characteristic corresponding to a kind of vortex that is insufficient to completely block the leakage flow D, a ball of such a scheme is further required.

Japanese Patent JP4926410B2

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a method and apparatus for controlling a combustion gas by forming a blow seal for generating a counter current flow opposite to a main flow direction of a combustion gas at a gap between a casing and a blade of the turbine. And it is an object of the present invention to provide a blade tip sealing apparatus for a gas turbine which can improve the energy efficiency of an engine by minimizing leakage loss.

In addition, the present invention reduces the risk of damage to the blade due to rubbing by ensuring a proper clearance between the casing and the blade of the turbine due to the formation of the blow seal, thereby maximizing the life of the blade and delaying the replacement cycle of the blade And it is an object of the present invention to provide a blade tip sealing apparatus of a gas turbine capable of pursuing economical efficiency.

According to an aspect of the present invention, there is provided a turbine engine including a casing configured to guide a flow of a combustion gas, a plurality of blades coupled to a rotating shaft in the casing, a shroud configured to surround a front end of the blades, And a blow seal which is formed in a plurality of peripheries along the circumference to generate a countercurrent flow in a direction opposite to the main flow of the combustion gas.

In the present invention, the blow seal may have at least one of a rectangular cross-sectional shape or various cross-sectional shapes, a horizontal wedge shape, a horizontal and vertical cross-sectional wedge shape, and an airfoil cross-sectional shape at the outer surface of the shroud .

In the present invention, the blow seal may be formed so as to have the same pitch at the inlet portion and the outlet portion with respect to the direction of the current flow, or may have different pitches at the inlet portion and the outlet portion based on the direction of the reflux flow Respectively.

In the present invention, the blow seal is disposed with a variable inclination angle with respect to the shroud.

The present invention further includes a flow guide vane protruding outwardly from an outer surface of the blow seal, wherein the flow guide vane is formed to be inclined upward from a base of the blow seal toward a free end thereof.

In addition, the flow guiding vanes are formed as a straight-line outlet extension or a streamline outlet extension extending the distance from the inlet to the outlet with respect to the direction of formation of the counterflow.

In addition, when the flow guiding vanes are of a streamlined outlet extension type, the flow guiding vanes are formed upwardly concave toward the free end of the blow seal, or upwardly convex.

The flow guide vane may include a first flow guide formed to be inclined upward from a base portion of the blow seal toward a free end thereof and a second flow guide portion that is inclined downward toward a base portion on the outlet side of the blow seal from the first flow guide portion. The first flow guide portion and the second flow guide portion are spaced apart from each other.

A plurality of blades coupled to a rotating shaft in the casing; a shroud disposed to surround a front end of the blades; a plurality of blades formed along the entire circumference of the shroud, And a turning device for variably controlling the inclination angle of the blow seal in accordance with the rotational speed of the blade. The present invention relates to a blade tip sealing apparatus for a gas turbine.

In the present invention, the swivel facility includes a hinge shaft for rotatably supporting the blow seal, a pressure chamber for rotatably receiving the hinge shaft therein, a rotor coupled to the hinge shaft and dividing the inside of the pressure chamber, And an operating mechanism for providing operating pressure within the pressure chamber defined by the rotor.

In the present invention, the operating facility includes: a plurality of pressure pipes formed in a communicating manner in the pressure chamber so as to be able to communicate with a space divided by the rotor; a direction control valve for controlling supply of operating pressure through the pressure pipe; A hydraulic pump for supplying an operating pressure into the pressure chamber, and a pressure control valve for regulating an operating pressure supplied to the directional control valve.

The present invention further includes a rotation speed detecting section for detecting the rotation speed of the blade and a control section for controlling the operation of the direction control valve and the pressure control valve in accordance with the rotation speed detected from the rotation speed detection section, Further comprising a relief valve for interrupting the supplied working pressure, wherein the relief valve is installed between the direction control valve and the pressure control valve.

The present invention minimizes the leakage loss of the combustion gas through the generation of the counter current flow in the direction opposite to the main flow direction of the combustion gas at the gap portion between the casing and the blade tip of the gas turbine, The effect will be provided.

In particular, the present invention relates to a method for optimizing the flow at the surface of a blow seal, with the application of various cross-sectional shapes, for example, by optimizing the shape of the blow seal to create a counter current flow opposite the main flow direction at the gap between the casing and the blade The leakage flow can be minimized by providing fluidity in a specific direction due to the addition of protrusions for guiding in the direction of the turbine. In particular, in setting the blow seal for the generation of the current flow, It is possible to minimize the loss due to leakage of the combustion gas.

In addition, the present invention can secure a minimum clearance that can completely eliminate the risk of rubbing caused by thermal deformation of the gap between the casing and the blades due to the operation time of the engine, And it is possible to provide an economic effect of delaying the replacement cycle of the blade as much as possible.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a partial sectional view for explaining the leakage loss of flow between a blade of a conventional gas turbine and a casing; Fig.
FIG. 2 is a perspective view schematically showing an installation state of a labyrinth seal provided in the turbine blade shown in FIG. 1 to reduce a leakage loss generated between the turbine blade and the casing.
3 is a view schematically showing an overall configuration of a gas turbine engine to which an embodiment of the present invention is applied.
4 is a partial cross-sectional view showing major components in a blade tip sealing apparatus of a gas turbine according to an embodiment of the present invention.
FIG. 5 is a perspective view schematically showing the installation state of the blow seal for reducing the leakage loss generated between the turbine blade and the casing shown in FIG. 4. FIG.
Figs. 6-9 are plan views partially illustrating various modifications of the cross-sectional shape of the blow seal, in various embodiments of the present invention.
FIGS. 10-13 are side views, partially illustrating various modifications of the side view of the blow seal, in various embodiments of the present invention. FIG.
14 is a perspective view partially showing a main constituent part of a swivel facility for variably controlling an inclination angle of a blow seal with respect to a tip end portion of a blade according to another embodiment of the present invention.
Fig. 15 is a diagram showing an overall configuration including a hydraulic circuit in the turning equipment shown in Fig. 14. Fig.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a view schematically showing an overall configuration of a gas turbine engine to which an embodiment of the present invention is applied.

3, the gas turbine engine includes an intake unit 10 for sucking outside air, a compressor 12 for compressing outside air sucked through the intake unit 10 to a high pressure, (14) which mixes high pressure compressed air with fuel and then burns it to generate a high temperature / high pressure combustion gas, and a combustor (14) for generating combustion gas from the high temperature / An exhaust unit 18 for exhausting the combustion gas passing through the turbine 16 to the outside and a generator 18 for interlocking the compressor 12 and the turbine 16, And a rotary shaft 20 for driving the rotary shaft 20.

The intake unit 10 serves as a part for receiving intake air from the outside and serves to guide the introduced outside air to the compressor 12. [ In this case, the inlet of the intake unit 10 is formed in a bellmouth shape so that a larger amount of outside air can be introduced.

The compressor 12 pressurizes the intake air flowing through the intake unit 10 and supplies the pressurized air to the combustor 14. The compressor 12 includes a guide vane for guiding the flow direction of the intake air, a rotor blade disposed at the rear of the guide vane and rotating together with the rotary shaft 20, and a stator vane disposed at the rear of the rotor blade. In this case, the compressor 12 alternately arranges the rotor blades and the stator vanes on the rotary shaft 20, and arranges the rotor blades and the stator vanes in a plurality of rows along the axial direction of the rotary shaft 20 And a multi-stage facility for progressively pressurizing the sucked air in various stages to switch to a high pressure state.

The combustor 14 is disposed radially over the entire circumference of the flow path of the air compressed by the compressor 12 at a high pressure and generates a high temperature / high pressure combustion gas as a result of combustion of a mixture of air and fuel . For example, the combustor 14 may be a Can type, a Annular type, a Can-Annular type, or the like.

The turbine 16 is a facility for generating power required for driving the generator by rotating by the flow of the high temperature / high pressure combustion gas provided through the combustor 14, And the rotor blades and the stator vanes are arranged in a plurality of rows along the axial direction of the rotating shaft (20). That is, the turbine 16 is installed alternately with the rotor blades and the stator vanes on the rotary shaft 20, and the rotor blades and the stator vanes are arranged along the axial direction of the rotary shaft 20 in multi- So as to convert the energy of the combustion gas into mechanical energy in the rotational direction.

The exhaust unit 18 discharges the combustion gas provided to the turbine 16 to the outside. In this case, the exhaust part 18 is structured so as to be able to communicate with a purifier for post-treatment of the exhaust gas in consideration of environmental problems such as air pollution. The rotary shaft 20 is a shaft member including the compressor 12 and the turbine 16 to rotate the generators together and rotate together. The shaft member 20 may be composed of a single shaft member or a plurality of shaft members.

3, an arrow marked with a reference A signifies the flow direction of the intake air flowing into the interior of the gas turbine through the intake unit 10, and an arrow marked with B indicates the flow direction of the compressor 12 And arrows denoted by reference character C are burned through the combustor 14 and then the turbine 16 is rotated and then discharged to the outside through the exhaust part 18. [ Means the flow direction of the discharged combustion gas.

Fig. 4 is a partial cross-sectional view showing major components in a blade tip sealing apparatus of a gas turbine according to an embodiment of the present invention, Fig. 5 is a cross- Fig. 3 is a perspective view schematically showing a state of installation of a blow seal for a blow seal.

Referring to FIGS. 4 and 5, the turbine 16 includes a honeycomb seal 24 for airtightness with the free end on the blade tip side corresponding to the tip portion of the blade 26 in the casing 22 ). That is, the honeycomb seals 24 are provided to surround the tips of the blades 26 from the outside over the entire circumference of the inner peripheral surface of the casing 22. At this time, a proper clearance is secured between the honeycomb seal 24 and the tip portion of the blade 26 to prevent damage to the member due to the contact.

The blade 26 generates a counter flow flow E directed in a direction opposite to the main flow C of the combustion gas provided from the combustor 14 so that the inner peripheral surface of the casing 22 or the honeycomb seal 24 to reduce the efficiency loss of the engine due to the leakage flow D of the combustion gas resulting from the formation of the gap. At this time, it is preferable that the degree of the rebound flow (E) generated by the tip sealing device is adjusted so as to be within a range that does not hinder the overall efficiency of the engine.

That is, the tip sealing apparatus is for generating a counter current (E) in a direction opposite to the main flow (C) of the combustion gas from the combustor (14) toward the turbine (16) E may be generated in the gap between the honeycomb seal 24 provided at the casing 22 and the blade 26, that is, the inner circumferential surface of the casing 22, and the distal end portion of the blade 26 Let's do it.

To this end, the tip sealing device is composed of a blow seal 30 formed on the outer surface of an annular shroud 28 provided at the front end of the blade 26. In this case, the blow seal 30 is provided in a plurality of quantities with equal spacing or unequally spaced distances over the entire outer surface of the shroud 28. The blow seal 30 is disposed to have a predetermined inclination angle with respect to a virtual reference line extending in the circumferential direction of the turbine blade 26. Particularly, the angle of inclination of the blow seal 30 is set such that the rebound flow E can be generated in a direction opposite to the main flow C of the combustion gas based on the rotation direction R of the blade 26 Respectively. That is, the countercurrent flow E of the combustion gas by the blow seal 30 corresponds to the incidental flow of the combustion gas generated from the rotation of the blade 26 by the main flow C of the combustion gas, And is generated in the opposite direction along the clearance between the blow seal 30 and the gap between the honeycomb seal 24 and the blow seal 30.

In summary, the tip sealing apparatus includes a casing 22 and a casing 22, which are arranged in a direction opposite to the main flow C of the combustion gas from the combustor 14 toward the turbine 16, And a blow seal 30 which can be generated at a gap between the honeycomb seal 24 provided at the blade 26 and the inner circumferential surface of the casing 22 and the tip of the shroud 28.

Figs. 6-9 are plan views partially illustrating various modifications of the cross-sectional shape of the blow seal, in various embodiments of the present invention.

Referring to FIG. 6, the blow seal 30 includes a plurality of (eg, a plurality of) cross-sectional shapes having a rectangular plate shape or various cross-sectional shapes with respect to a horizontal direction parallel to the tangential direction on the outer surface of the shroud 28 . At this time, a plurality of blow seals 30 formed of the square cross-section or various cross-sectional members are arranged at equal intervals or unequally spaced from the outer surface of the shroud 28.

That is, the blow seal 30 having a square cross section or a variety of cross sectional shapes has an interval (pitch, P) corresponding to an inlet portion (right side in the drawing) and an outlet portion (Pitch, P) of the portion corresponding to the reference position (reference left side) are set at regular intervals. Alternatively, the blow seal 30 having a square cross section or a variety of cross sectional shapes may be formed to have different distances (pitches P) between the inlet portions (pitch P) and outlet portions (pitches P) for minimizing the leakage flow D with respect to the combustion gas And may be arranged at unequal intervals. The blow seal 30 having a square cross section or a variety of cross sectional shapes can also be arranged to set the inclination angle A to an optimal state with respect to the shroud 28 in order to minimize the leakage flow D of the combustion gas have. For example, the inclination angle A of the blow seal 30 with respect to the shroud 28 may be set to be the same or different from each other.

7, the blow seal 30 is formed in a triangular wedge shape in which the cross-sectional shape gradually decreases with respect to a horizontal direction parallel to the tangential direction on the outer surface of the shroud 28 And is constituted by a plurality of members to be set. At this time, a plurality of blow seals (30) formed by members having a wedge cross section are arranged at equal intervals or unequal intervals on the outer surface of the shroud (28).

That is, the wedge-shaped blow seal 30 of the horizontal section has a gap (pitch, P) corresponding to an inlet portion (right side in the drawing) and an outlet portion (Pitch, P) are arranged at regular intervals. Alternatively, the wedge type blow seal 30 may be formed at a different spacing (pitch, P) by setting the intervals (pitch, P) of the inlet portions and the intervals (pitches, P) of the outlet portions to be different from each other to minimize the leakage flow D with respect to the combustion gas . The wedge-shaped blow seal 30 of the horizontal section may also be arranged with the inclination angle A set to the optimum state with respect to the shroud 28 in order to minimize the leakage flow D of the combustion gas. For example, the inclination angle A of the blow seal 30 with respect to the shroud 28 may be set to be the same or different from each other. Particularly, in the wedge-type blow seal 30, the wedge-shaped cross-sectional direction is formed by arranging a leading edge at the inlet of the turbulent flow E and a trailing edge at the outlet of the turbulent flow E the trailing edge may be disposed at the inlet of the turbulent flow E or the leading edge may be disposed at the outlet of the turbulent flow E while placing the trailing edge at the inlet of the turbulent flow E.

Referring to FIG. 8, the blow seal 30 is formed in a triangular wedge shape in which the cross-sectional shape gradually decreases with respect to a horizontal direction parallel to the tangential direction on the outer surface of the shroud 28, And a plurality of members that are set in a wedge shape in a triangular shape in which the cross-sectional area gradually decreases with respect to a direction perpendicular to the direction in which the blade 26 is formed. At this time, a plurality of blow seals (30) formed by members having a wedge cross section are arranged at equal intervals or unequal intervals on the outer surface of the shroud (28).

That is, the wedge-shaped blow seal 30 of the horizontal and vertical cross-sections corresponds to the gap of the portion corresponding to the inlet portion (the reference right side) and the outlet portion (left side of the drawing reference) (Pitch, P) are set at regular intervals. Alternatively, the wedge type blow seal 30 may be formed at a different spacing (pitch, P) by setting the intervals (pitch, P) of the inlet portions and the intervals (pitches, P) of the outlet portions to be different from each other to minimize the leakage flow D with respect to the combustion gas . In addition, the wedge-shaped blow seal 30 of the horizontal and vertical cross-sections can be arranged to set the tilt angle A to an optimal state with respect to the shroud 28 to minimize the leakage flow D of the combustion gas have. For example, the inclination angle A of the blow seal 30 with respect to the shroud 28 may be set to be the same or different from each other. Particularly, in the wedge-type blow seal 30, the wedge-shaped cross-sectional direction is formed by arranging a leading edge at the inlet of the turbulent flow E and a trailing edge at the outlet of the turbulent flow E the trailing edge may be disposed at the inlet of the turbulent flow E or the leading edge may be disposed at the outlet of the turbulent flow E while placing the trailing edge at the inlet of the turbulent flow E.

Referring to FIG. 9, the blow seal 30 is formed in the form of an airfoil whose cross-sectional shape gradually decreases with respect to a horizontal direction parallel to the tangential direction on the outer surface of the shroud 28 And is constituted by a plurality of members to be set. At this time, a plurality of blow seals 30 formed by members having an airfoil-shaped cross-section are arranged on the outer surface of the shroud 28 at regular intervals or unequally spaced intervals.

That is, the blow seal 30 having the cross-sectional shape of the airfoil has an interval (pitch, P) corresponding to the inlet portion (the reference right side) and an outlet portion (Pitch, P) at regular intervals. Alternatively, the airfoil-type blow seal 30 may be formed by setting the interval (pitch, P) of the inlet portion and the interval (pitch, P) of the outlet portion to be different from each other to minimize the leakage flow D with respect to the combustion gas, As shown in FIG. The airfoil type blow seal 30 may be disposed with the inclination angle A set to the optimum state with respect to the shroud 28 in order to minimize the leakage flow D of the combustion gas. For example, the inclination angle A of the blow seal 30 with respect to the shroud 28 may be set to be the same or different from each other. In particular, in the airfoil-type blow seal 30, the cross-sectional direction in the form of an airfoil is the trailing edge of the traversing flow E, with the leading edge at the inlet of the counterflow flow E, It is also possible to dispose a trailing edge or, conversely, arrange the leading edge at the exit of the turbulent flow (E) while placing the trailing edge at the inlet of the turbulent flow (E).

In summary, the blade tip sealing apparatus of the gas turbine according to the present invention is capable of generating a rebound flow (E) by the combustion gas in accordance with the formation of the blow seal 30, as shown in FIGS. 6 to 9, respectively The efficiency of the engine is improved by minimizing the degree of the leakage flow D that is branched from the main flow C of the combustion gas and directed toward the gap between the honeycomb seal 24 of the casing 22 and the tip of the blade 26 It is possible to contribute to improvement.

FIGS. 10-13 are side views, partially illustrating various modifications of the side view of the blow seal, in various embodiments of the present invention. FIG.

10, the blow seal 30 is formed so that the flow direction of the combustion gas with respect to the counter current flow E is a gap between the inner circumferential surface of the honeycomb seal 24 located on the inner circumferential surface of the casing 22 A plurality of protruding flow guiding vanes 32 protruding from the outer surface toward the outside are formed and the direction of the flow guiding vanes 32 is changed from the base portion toward the shroud 28 from the blow seal 30, 22 toward the free end toward the honeycomb seals 24. As shown in Fig. In particular, the flow guiding vanes 32 are formed on at least one of the two sides of the blow seal 30. [

At this time, the plurality of the flow guiding vanes 32 are spaced apart from the surface of the blow seal 30 at a predetermined interval. Particularly, the flow guiding vanes 32 are disposed at the outlet portion (left side in the figure) from the inlet portion (right side in the figure) with reference to the direction of the formation of the counter flow flow E by the combustion gas as the blow seal 30 is formed, So as to expand the mutual separation distance. In this case, the overall contour of the flow guiding vanes 32 is in the form of a straight line.

Accordingly, the distribution of the rebound flow (E) set by the linear outlet-side expandable flow vanes (32) can be uniformly dispersed and diffused from the inlet portion to the outlet portion of the blow seal (30) To contribute to minimizing the degree of the leakage flow D toward the gap between the honeycomb seal 24 of the casing 22 and the tip of the blade 26, branched from the main flow C of the casing 22 .

Referring to FIG. 11, the flow guiding vanes 32 are formed in the same arrangement as the flow guiding vanes 32 shown in FIG. However, each of the flow guide vanes 32 is formed to have a curved curvature from the bottom of the blow seal 30 toward the honeycomb seal 24 of the casing 22 in an upward concave shape. In the case of the stream-type outlet-side expandable flow-guiding vanes 32, which are set in this manner, similar effects to those of the guide vanes shown in Fig. 10 can be achieved, and in particular, the honeycomb- It is possible to provide an effect of further accelerating the counterflow flow E toward the gap portion between the tip ends of the blades 26.

Referring to Fig. 12, the flow guiding vanes 32 are formed in the same arrangement as the flow guiding vanes 32 shown in Figs. 10 and 11, respectively. 11, each of the flow guide vanes 32 is formed in a shape of upward convex from the base of the blow seal 30 toward the honeycomb seal 24 of the casing 22, As shown in Fig. In the case of the stream-type outlet-side expandable flow-guiding vanes 32 set in this manner, similar effects to those of the vanes shown in Figs. 10 and 11 can be realized, and in particular, the honeycomb- (E) toward the outlet of the blow seal (30) as well as the counter flow (E) toward the gap between the blade (24) and the tip of the blade (26) .

13, the flow guiding vanes 32 are different from the flow guiding vanes 32 shown in Figs. 10 to 12, respectively, in that the base of the blow seal 30, at the inlet of the blow seal 30, A first flow guide portion 32a which is set to be inclined upward toward the honeycomb seal 24 of the casing 22 from the first flow guide portion 32a, And a second flow guide portion 32b which is inclined downward toward the base portion. That is, Fig. 13 corresponds to a blow seal 30 having a streamlined composite flow vane 32.

At this time, the first flow guide portion 32a and the second flow guide portion 32b are spaced apart from each other by a predetermined distance. Accordingly, the initial flow of the counter flow (E) due to the formation of the first flow guide portion (32a) causes the clearance between the honeycomb seal (24) of the casing (22) and the tip portion of the blade The end flow of the rebound flow E along the second flow guide portion 32b can be prevented from flowing to the outlet portion of the blow seal 30 It is possible to contribute to blocking the initial entry of the leakage flow D toward the gap portion.

14 is a perspective view partially showing a main constituent part of a swivel facility for variably controlling the inclination angle of the blow seal with respect to the tip of the blade as another embodiment of the present invention, Fig. 2 is a diagram showing an overall configuration including a hydraulic circuit in a facility.

14 and 15, the blow seal 30 variably adjusts the inclination angle of the blow seal 30 with respect to the shroud 28 corresponding to the rotational speed of the blade 26, And a turning device for freely controlling the degree of generation of the flow (E).

The swivel facility includes a hinge shaft 34 formed on the blow seal 30 to freely adjust the inclination angle of the blow seal 30 with respect to the shroud 28 and rotatably supporting the blow seal 30, A pressure chamber 36 which receives the hinge shaft 34 therein and rotatably supports the hinge shaft 34; a rotor 36 which is coupled to the hinge shaft 34 and divides the internal space of the pressure chamber 36 in an airtight state (38) in the pressure chamber (36) by providing a separate operating pressure within the pressure chamber (36) and into the airtightly divided space with the rotor (38) And an operating device for rotating the hinge shaft 34 by implementing rotation.

In this case, the hinge shaft 34 is formed at a lower end of one side of the blow seal 30, and the pressure chamber 36 is disposed inside the shroud 28, and the leakage flow D and the counterflow flow E To minimize the leakage space. The stopper 36a protrudes inward to limit the rotation angle of the pressure chamber 36. The position of the stopper 36a is determined by the position of the shroud 28, Of the blow seal (30). As a result, the rotation angle of the rotor 38 in the pressure chamber 36 can be limited to a range defined by the stopper 36a. Therefore, the angle of the hinge shaft 34 with respect to the pressure chamber 36 The rotation angle is also limited depending on the angle of inclination of the blow seal 30 with respect to the shroud 28 to be limited to a desired range.

In addition, the operating facility includes a plurality of pressure pipes (40) formed in the pressure chamber (36) so as to communicate with the space divided by the rotor (38) A direction control valve 42 for switching the port to provide the supply of operating pressure using one of the pressure conduits 40 and a direction control valve 42 for controlling the degree of the operating pressure supplied to the direction control valve 42 A relief valve 46 for interrupting the supply of operating pressure in case of an excessive operating pressure supplied through the pressure line 40, And a hydraulic pump 48 for generating operating pressure through the pressure conduit 40 for rotation of the rotor 38 within the valve body 40. [

In this case, the pressure conduit 40 is formed to communicate with the inside of the pressure chamber 36 via the shroud 28 via the rotary shaft 20 and the blade 26. It is needless to say that in the operation equipment, the rest of the configuration except for the pressure pipe 40 is installed at a position that can eliminate interference with the operation element such as the blade 26 including the rotation shaft 20. In particular, the relief valve 46 is installed in the pressure pipe 40 located between the direction control valve 42 and the pressure control valve 44 so that the supply pressure supplied from the pressure control valve 44 is excessive , It functions to protect the operation equipment.

The swivel facility includes a control unit 50 for variably controlling the inclination angle of the blow seal 30 with respect to the blade 26 in accordance with the rotation speed of the blade 26, And a rotation speed detecting unit 52 for detecting and providing the driving speed of the turbine 16 or the blade 26. [ In the drawing, reference numeral 54 denotes an oil pan for supplying hydraulic oil to the hydraulic pump 48.

In this case, the control unit 50 outputs an appropriate operation signal to the solenoid of the directional control valve 42 according to the driving speed of the turbine 16 inputted through the rotational speed detecting unit 52, Since the operating pressure is limited to any one of the two internal spaces hermetically partitioned about the rotor 38 in the hinge shaft 36, the rotation of the hinge shaft 34 can be realized.

The control unit 50 controls the flow rate of the operating pressure supplied to the pressure chamber 36 through the directional control valve 42 in accordance with the driving speed of the turbine 16 input through the rotational speed detecting unit 52 , Which is implemented by a series of pressure controls on the pressure control valve 44. [ For example, the control unit 50 may control the operation signal provided to the solenoid of the pressure control valve 44 according to the selection of the duty value, or may control the linear output value in a proportional control manner.

Hereinafter, the operation of the blade tip sealing apparatus of a gas turbine according to the embodiment of the present invention will be described in detail.

The high temperature / high pressure combustion gas flow which is burned through the combustor 14 is divided into a main flow C contributing to the generation of energy by rotating the blade 26 of the turbine 16, And a leakage flow D through the gap between the shrouds 28 located at the free end of the blade 26. [

In this case, the leakage flow D of the combustion gas is reduced by the counter current flow E formed by the blow seal 30. 6 to 9, the blow seal 30 having various cross-sectional shapes is formed in a direction opposite to the main flow C of the combustion gas as the blade 26 rotates, So that the generation of the counterflow flow E minimizes the leakage flow D generated in the gap between the casing 22 and the shroud 28. [

For example, the blow seal 30 having the rectangular cross section shown in FIG. 6 is disposed on the outer surface of the shroud 28 in a plurality of equidistant or unequally spaced distances over the entire circumference, so that the blow seal 30 (E) of the combustion gas set in the direction opposite to the main flow (C) of the combustion gas in the space between the casing (22) and the shroud (28) The amount of the leakage flow D that is directly discharged to the exhaust part 18 without passing through the blade 26 of the exhaust pipe 18 can be minimized.

In the case of the wedge type blow seal 30 of the horizontal cross section shown in Fig. 7, it is formed in the direction opposite to the main flow C of the combustion gas, like the blow seal 30 of the rectangular cross section of Fig. 6 In generating the counter flow (E), the initial velocity of the combustion gas entering the space between the blow seals (30) through the placement of the trailing edge at the outlet of the flow with the placement of the leading edge at the inlet of the flow Thereby making it possible to further contribute to minimizing the leakage flow D. When the leading edge and the trailing edge of the wedge type blow seal 30 of the horizontal section are reversely disposed, the speed of the end of the combustion gas toward the outlet of the flow is increased and the casing 22 and the shroud 28 , It is possible to contribute to improving the efficiency of the engine by blocking the initial entry of the leakage flow D toward the gap portion between the engine and the engine.

The wedge type blow seal 30 of the horizontal and vertical cross section shown in Fig. 8 is similar to the wedge type blow seal 30 of the horizontal cross section shown in Fig. 7 except that the casing 22 and the shroud 28, It is possible to minimize the leakage flow D toward the gap between the blow seal 30 and the blow seal 30. Particularly, by changing the cross sectional area in the vertical direction of each blow seal 30, It is possible to provide a more improved effect in minimizing the leakage flow D since the pressure can be changed.

The airfoil type blow seal 30 shown in FIG. 9 has a degree of production of a rebound flow E formed through effective arrangement of curved portions based on the rotational direction R of the blade 26 The leakage flow D through the gap between the casing 22 and the shroud 28 can be maximally reduced, thereby contributing to the improvement of the efficiency of the engine.

As shown in FIGS. 10 to 13, the blow seal 30 having various side shapes is formed by forming the flow guiding vanes 32 protruding toward the outside, So that it is possible to reduce the leakage flow D through the gap between the casing 22 and the shroud 28. [

For example, as shown in Fig. 10, the straight outlet-type extended flow guide vanes 32, which extend the separation distance toward the outlet portion of the rebound flow E, are moved from the inlet portion to the outlet portion of the blow seal 30, (D) branched through the gap between the casing (22) and the shroud (28) is branched from the main flow (C) of the combustion gas since the distribution of the flow (E) .

11 and 12, the stream-like outlet extension expanding flow guide vanes 32, which extend the separation distance toward the outlet portion of the rebound flow E, extend from the inlet portion of the blow seal 30 (E) toward the outlet of the blow seal 30 along with the gap between the casing 22 and the shroud 28, as well as to uniformly distribute and diffuse the distribution of the counter- E) can be promoted together.

The streamlined composite flow vanes 32 shown in Fig. 13 are arranged in such a manner that the initial flow direction of the rebound flow E is formed through the formation of the first flow guide portion 32a in the casing 22 and the shroud 28), it contributes to shutting off the leakage flow (D) that has entered the gap portion. By forming the second flow guide portion (32b), the end flow of the rebound flow (E) (D) toward the gap portion, it is possible to prevent the leakage flow D from flowing into the gap between the casing (22) and the shroud (28) It is possible to minimize the leakage flow D that occurs through the gap portion of the gasket.

14 and 15, the angle of inclination of the blow seal 30 can be variably controlled in conjunction with the rotation speed of the blade 26, And the leakage flow D through the gap between the shroud 28 and the shroud 28.

That is, the control unit 50 controls the rotation speed of the blade 26 based on the rotation speed of the blade 26 detected through the rotation speed detection unit 52, The rotation angle of the hinge shaft 34 can be changed to adjust the supply of the operating pressure to the divided space defined by the rotor 38, 30 can be arbitrarily adjusted.

In this case, since the control unit 50 can variably adjust the degree of the operating pressure supplied into the pressure chamber 36 through various pressure control on the pressure control valve 44, the inclination angle of the blow seal 30 It is possible to more flexibly control the rotation direction of the blade 26 in accordance with the rotation speed of the blade 26 in changing the directionality of the generated current E.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be construed as limited to the particular details of the embodiments set forth herein. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims.

In the preferred embodiment of the present invention, the blow seal is formed on the outer surface of the shroud. However, the blow seal may be formed directly on the free end of the blade, And may be configured to create a rebound flow towards the gap region.

10-intake part 12-compressor
14-Combustor 16-Turbine
18-exhaust part 20-rotation shaft
22-casing 24-honeycomb seal
26-Blade 28-Shroud
30-Blow Seal 32-Flowing Conduit
34-Hinge shaft 36-Pressure chamber
38-rotor 40-pressure tube
42-way control valve 44-Pressure control valve
46-Relief Valve 48-Hydraulic Pump
50-control unit 52-rotation speed detection unit
54 - Oil pan

Claims (22)

A casing configured to guide the flow of the combustion gas;
A plurality of blades coupled to the rotating shaft in the casing;
A shroud installed to surround the tip of the blade;
A blow seal formed in the shroud along the front perimeter to generate a counter current flow in a direction opposite to the main flow of the combustion gas; And
And a plurality of flow guiding fingers protruding outward from an outer surface of the blow seal. The method according to claim 1,
Wherein the blow seal is formed in a rectangular cross-sectional shape or in various cross-sectional shapes on the outer surface of the shroud. The method according to claim 1,
Wherein the blow seal is formed in a wedge shape having a horizontal cross section at an outer surface of the shroud. The method according to claim 1,
Wherein the blow seal is formed in a wedge shape of horizontal and vertical cross-sections at an outer surface of the shroud. The method according to claim 1,
Wherein the blow seal is formed in an airfoil cross-sectional shape at an outer surface of the shroud. The method according to any one of claims 2 to 5,
Wherein the blow seal is formed to have the same pitch at the inlet and outlet portions with respect to the direction of the rebound flow. The method according to any one of claims 2 to 5,
Wherein the blow seal is formed to have a different pitch at an inlet portion and an outlet portion with respect to a direction of the reflux flow. The method according to any one of claims 2 to 5,
Wherein the blow seal is disposed with variable tilt angles with respect to the shroud. delete The method according to claim 1,
Wherein the flow guide vane is formed in an upward inclined shape from a base portion of the blow seal toward a free end thereof. The method of claim 10,
Wherein the flow guiding vanes are of a straight-line outlet extension extending from the inlet to the outlet with respect to the direction of formation of the counter flow. The method of claim 10,
Wherein said flow guiding vanes comprise a streamlined outlet extension extending a distance away from the inlet to the outlet with respect to the direction of formation of the rebound flow. The method of claim 12,
Wherein the flow guiding vane is formed upwardly concave or upwardly convex from the base of the blow seal toward the free end. The method of claim 10,
Wherein the flow guide vane has a first flow guide portion formed in a shape inclined upward from a base portion of the blow seal toward a free end thereof and a second flow guide portion that is inclined downwardly from the first flow guide portion toward a base portion on the outlet side of the blow seal And a second flow guide formed in the second flow guide portion. 15. The method of claim 14,
Wherein the first flow guide portion and the second flow guide portion are spaced apart from each other. A casing configured to guide the flow of the combustion gas;
A plurality of blades coupled to the rotating shaft in the casing;
A shroud installed to surround the tip of the blade;
A blow seal formed in the shroud along the front perimeter to generate a counter current flow in a direction opposite to the main flow of the combustion gas; And
And a turning device for variably controlling the inclination angle of the blow seal in accordance with the rotation speed of the blade. 18. The method of claim 16,
A hinge shaft rotatably supporting the blow seal;
A pressure chamber rotatably receiving the hinge shaft therein;
A rotor coupled to the hinge shaft and dividing the interior of the pressure chamber; And
And operating means for providing operating pressure within the pressure chamber defined by the rotor. ≪ Desc / Clms Page number 13 > 18. The method of claim 17,
A plurality of pressure conduits formed in the pressure chamber so as to be able to communicate with a space divided by the rotor;
A direction control valve for regulating the supply of operating pressure through the pressure line; And
And a hydraulic pump for supplying operating pressure into the pressure chamber. 19. The method of claim 18,
Further comprising a pressure control valve for adjusting the operating pressure supplied to the directional control valve. The method of claim 19,
A rotation speed detector for detecting a rotation speed of the blade; And
And a control unit for controlling the operation of the directional control valve and the pressure control valve in accordance with the rotational speed detected from the rotational speed detecting unit. The method of claim 19,
Further comprising a relief valve for shutting off the operating pressure supplied to the pressure chamber. 23. The method of claim 21,
Wherein the relief valve is installed between the directional control valve and the pressure control valve.

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