CN115478906A

CN115478906A - Radial clearance adjusting device for turbine engine

Info

Publication number: CN115478906A
Application number: CN202211179704.0A
Authority: CN
Inventors: 孙万超; 阮昌龙; 闫晨辉; 王月; 李富才
Original assignee: Qingdao Institute Of Aeronautical Technology; Institute of Engineering Thermophysics of CAS
Current assignee: Qingdao Institute Of Aeronautical Technology; Institute of Engineering Thermophysics of CAS
Priority date: 2022-09-27
Filing date: 2022-09-27
Publication date: 2022-12-16

Abstract

The invention relates to a radial clearance adjustment device for a turbine engine, comprising: the turbine blade assembly comprises a shell, a guide blade fixed in the shell and a turbine blade arranged in the center of the shell; the guide ring comprises a positioning ring, a central ring integrally arranged in the center of the guide ring and shutter rings respectively arranged on two sides of the central ring, a main channel is arranged in the central ring, and the main channel is communicated with the cooling hole; and a secondary channel and a valve channel are arranged in the valve ring, and the secondary channel is communicated with the cooling hole. The radial clearance adjusting device for the turbine engine can maintain enough radial clearance in the starting process of the turbine through the design of the graded guide ring, effectively reduce air leakage, improve the working efficiency of the turbine and solve the technical problem of air leakage control of the turbine blades at present.

Description

Radial clearance adjusting device for turbine engine

Technical Field

The invention belongs to the field of engine structure design, and particularly relates to a radial clearance adjusting device for a turbine engine.

Background

Turbomachines (e.g., centrifugal compressors, turbines, etc.) often operate at high temperatures, and both their rotor components as well as their stator components undergo high temperature expansion processes.

In a quick start machine, i.e. a machine that performs a quick start procedure within a short period of time, the seal gap between the sealing arrangement mounted on the stationary component and the rotating component must be designed such that during quick start the sealing arrangement does not contact the rotating component, which is subject to a rapid increase in size due to centrifugal and thermal radial growth in the radial direction.

To prevent seal damage during start-up due to stator radial growth being slower than rotor radial growth, the diameter of the seal arrangement is dimensioned so as to maintain sufficient radial clearance also at fast start-up. Thus, when steady state operating conditions of the turbine are reached, the radial seal clearance is relatively large. However, the large radial clearance results in a decrease in the efficiency of the turbine. Accordingly, there is a need for improved control of the radial clearance of a sealing arrangement in a turbine operating at high temperatures and having a rapid start-up procedure.

In order to solve the problem of the air leakage control of the turbine blade, the invention provides a novel radial clearance adjusting device.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a radial clearance adjusting device for a turbine engine, which can ensure that a turbine can maintain enough radial clearance in the starting process through the design of a grading guide ring, and can reduce air leakage and greatly improve the working efficiency of the turbine on the basis of maintaining the radial clearance of a grate-shaped channel formed by the grading guide ring after stable work so as to solve the technical problem of controlling the air leakage of the turbine blade at present.

The present invention provides a radial clearance adjustment apparatus for a turbine engine, comprising:

the whole shell is annular, a guide groove is formed in the shell, and a cooling hole for introducing a coolant is formed in the shell;

the guide blades are fixed in the shell, are arranged along the circumferential direction of the shell, and are arranged in a plurality of rows along the axial direction of the shell;

the turbine blade is integrally axial-flow type and is arranged at the central position inside the shell; and

the guide ring is integrally arranged in the guide groove and forms an air channel together with the turbine blade in the shell;

wherein, the guide ring further includes:

the positioning ring is provided with a positioning surface, and the positioning ring is arranged close to the guide groove through the positioning surface;

the center ring is integrally arranged in the center of the guide ring, a main channel is arranged in the center ring and is communicated with the cooling hole, and the center ring is cooled by injecting a coolant into the cooling hole; and

the valve ring is arranged on two sides of the central ring, a secondary channel and a valve channel are arranged in the valve ring, the secondary channel and the valve channel are not communicated with each other, the secondary channel is communicated with the cooling hole, a coolant is injected into the cooling hole to cool the valve ring, and the valve channel is communicated with the bottom of the main channel.

In some of these embodiments, the cooling holes open into the housing and extend in a vertical direction all the way into the interior of the housing until they communicate with the primary and secondary channels in the guide ring.

In some of these embodiments, the number of cooling holes is one or more, and the coolant is cooling air or water.

In some embodiments, the cross section of the guide groove is a T-shaped structure, the T-shaped structure includes a horizontal portion and a vertical portion, the horizontal portion is integrally disposed at a middle position inside the housing, and the vertical portion is disposed below the horizontal portion and extends to the bottom of the housing.

In some embodiments, two positioning rings are arranged and are respectively arranged at two sides of the valve ring, and the two positioning rings do not correspond to the axial positions of the turbine blades, so that the turbine blades and the positioning rings are not scraped;

the transversal structure of falling L of personally submitting of holding ring, the structure of falling L includes the holding ring body that vertical direction set up and sets up in the locating surface along the level of holding ring body top, makes the holding ring insert in the horizontal part of guide way through the level to the locating surface, and final two holding rings set up near the guide way.

In some embodiments, the main channel is integrally disposed inside the center ring, the main channel includes a first main channel and a second main channel disposed below the first main channel, the first main channel is disposed in a vertical direction and is communicated with the cooling hole, the second main channel is disposed in a horizontal direction and is communicated with the first main channel, and the first main channel and the second main channel are integrally formed in an annular structure, and the coolant flows through the first main channel and the second main channel by injecting the coolant into the cooling hole, so as to cool the center ring;

the secondary channel is integrally of an inverted L-shaped structure, the inverted L-shaped structure comprises a horizontal channel and a vertical channel arranged below the horizontal channel, the horizontal channel is communicated with the cooling hole, the vertical channel extends downwards in the valve ring all the time, and the coolant flows through the horizontal channel and the vertical channel in sequence by injecting the coolant into the cooling hole and is used for cooling the valve ring;

the valve channel is arranged below the secondary channel and is not communicated with the secondary channel, a single valve is arranged in the valve channel and is communicated with the second main channel in the main channel, and the single valve is used for adjusting the circulation of the coolant between the valve channel and the main channel.

In some embodiments, the ratio of the coolant flowing through the interior of the shutter channel to the coolant flowing through the interior of the main channel is (0.1-0.3): 1.

in some embodiments, the turbine blades are arranged in a plurality, the plurality of turbine blades are arranged on the rotating shaft at the central position of the bottom of the shell, are positioned between the two rows of guide blades and are supported by the bearings, and the plurality of turbine blades rotate together with the rotating shaft so as to form a rotating sweeping edge.

In some embodiments, a heat insulating layer is further provided between the guide ring and the casing, and the heat insulating layer enables the guide ring to be in a heat insulating state relative to the casing, so that the casing cannot shrink towards the direction of the blade.

Compared with the prior art, the invention has the advantages and beneficial effects that:

1. according to the radial clearance adjusting device for the turbine engine, due to the design of the grading guide ring, the turbine can maintain enough radial clearance in the starting process, after stable work, the grate tooth-shaped channel formed by the grading guide ring can reduce air leakage on the basis of maintaining the radial clearance, the working efficiency of the turbine is greatly improved, and the technical problem of air leakage control of the turbine blade at present is solved;

2. the radial clearance adjusting device for the turbine engine provided by the invention realizes effective control of the air leakage of the turbine blades, and further improves the working efficiency of the turbine.

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, illustrate embodiment(s) of the invention and together with the description serve to explain the invention and do not constitute a limitation of the invention. In the drawings:

FIG. 1 is a schematic overall cross-sectional view of an embodiment of a radial clearance adjustment apparatus for a turbine engine according to the present invention;

FIG. 2 is a cross-sectional view of a turbine engine just after start-up of an embodiment of a radial clearance adjustment apparatus for a turbine engine according to the present invention;

FIG. 3 is a sectional view of a turbine in the case of a steady operation of an embodiment of the radial gap adjustment apparatus for a turbine engine according to the present invention.

In the above figures:

1. a housing; 2. a guide groove; 3. a cooling hole; 4. a guide vane; 5. a turbine blade; 6. a positioning ring; 7. a center ring; 8. a shutter ring; 9. a first main channel; 10. a second main channel; 11. a secondary channel; 12. a valve passage; 13. a heat insulating layer; 14. a single valve; 15. positioning the surface; 16. an air channel;

41. a leading edge; 42. a trailing edge.

Detailed Description

The technical solutions in the embodiments will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. It is to be understood that the described embodiments are merely a few embodiments of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "central," "lateral," "longitudinal," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present invention and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting.

The terms "first", "second" and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", "third" may explicitly or implicitly include one or more of the features.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

As shown in fig. 1, in an exemplary embodiment of the radial gap adjustment apparatus for a turbine engine according to the present invention, the radial gap adjustment apparatus for a turbine engine mainly includes: the turbine blade assembly includes a casing 1, a guide groove 2 provided in the casing 1, a guide ring provided integrally in the guide groove 2, a guide blade 4 fixed to the bottom of the casing 1, and a turbine blade 5 attached to the center of the bottom of the casing 1. The following will describe these several key components in detail:

with reference to fig. 1, a casing 1 is annular, a plurality of guide vanes 4 are fixed inside the casing 1, the guide vanes 4 are arranged circumferentially inside the casing 1, and are arranged in a plurality of rows along the axial direction of the casing 1, and each guide vane 4 specifically includes a leading edge 41 and a trailing edge 42 through which a working medium flows; the turbine blades 5 are axially arranged as a whole, the plurality of turbine blades 5 are provided in common, the plurality of turbine blades 5 are mounted on a rotating shaft (not shown) at a central position inside the casing 1 and supported by bearings (not shown), and the plurality of turbine blades 5 rotate together with the rotating shaft and have a rotating swept edge. Furthermore, in other embodiments, a plurality of turbine blades 5 may also be connected to the rotating shaft by a balancing drum (not shown in the figures). Inside the housing 1, guide grooves 2 are provided, in which guide grooves 2 a guide ring is arranged in its entirety and which, together with the turbine blades 5 inside the housing 1, forms air channels 16. Specifically, the cross section of the guide groove 2 is a T-shaped structure including a horizontal portion integrally disposed at an intermediate position inside the housing 1 and a vertical portion disposed below the horizontal portion and extending up to the bottom of the housing 1. The top of the housing 1 is provided with cooling holes 3 for introducing a coolant, the cooling holes 3 extend in the vertical direction all the way into the housing 1 until communicating with a plurality of channels in the guide ring, and one or more cooling holes 3 can be provided, and the coolant used is cooling air or water. In addition, the present invention further provides a heat insulating layer 13 (for example, a thermal barrier coating or the like) between the guide ring and the casing 1, and the heat insulating layer 13 insulates the guide ring from the casing 1 so that the casing 1 does not contract in the vane direction.

Next, the guiding ring further comprises a center ring 7, a shutter ring 8 and a positioning ring 6 made of the same material in close contact, and as can be seen from fig. 1, the above-mentioned rings are arranged in the order of the positioning ring 6, the shutter ring 8 and the center ring 7 from the upstream to the downstream. Wherein, holding ring 6 sets up two altogether, locates the 8 both sides of valve ring branch, and two holding rings 6 do not correspond with the axial position of turbine blade 5 for do not produce the scraping between turbine blade 5 and the holding ring 6, every holding ring 6 all has locating surface 15, can be with holding ring 6 near the guide way 2 setting through locating surface 15. The actual function of the positioning surface 15 is further described below by combining the cross-sectional structure of the positioning ring 6, the cross section of the positioning ring 6 is of an inverted L-shaped structure, the inverted L-shaped structure comprises a positioning ring 6 body arranged in the vertical direction and a positioning surface 15 arranged at the top of the positioning ring 6 body along the horizontal direction, the positioning ring 5 is inserted into the horizontal part of the guide groove 2 through the horizontal positioning surface 15, and finally the two positioning rings 6 are arranged close to the guide groove 2, so that the positioning ring 6 can be accurately positioned.

The two valve rings 8 are arranged on two sides of the central ring 7 respectively, secondary channels 11 and valve channels 12 are arranged inside the valve rings 8, the secondary channels 11 and the valve channels 12 are not communicated with each other, the secondary channels 11 are communicated with the cooling holes 3, the valve rings 8 are cooled by injecting coolant into the cooling holes 3, and the valve channels 12 are communicated with the bottom of a main channel inside the central ring 8. Specifically, the secondary channel 11 is integrally in an inverted L-shaped structure, the inverted L-shaped structure includes a horizontal channel and a vertical channel disposed below the horizontal channel, the horizontal channel is communicated with the cooling hole 3, the vertical channel extends downward in the valve ring 8, and by injecting a coolant into the cooling hole 3, the coolant flows through the horizontal channel and the vertical channel in sequence for cooling the valve ring 8; the valve channel 12 is arranged below the secondary channel 11 and is not communicated with the secondary channel 11, a single valve 14 is arranged in the valve channel 12 and is communicated with the second main channel 10 in the main channel in the central ring 8, and the single valve is used for adjusting the circulation of the coolant between the valve channel 12 and the main channel.

The center ring 7 is integrally disposed at the center of the guide ring, a main passage is provided inside the center ring 7, the main passage communicates with the cooling holes 3, and the center ring 7 is cooled by injecting a coolant into the cooling holes 3. Specifically, the main channel is integrally arranged inside the center ring 7, the main channel further comprises a first main channel 9 and a second main channel 10 arranged below the first main channel 9, the first main channel 9 is arranged in the vertical direction and communicated with the cooling holes 3, the second main channel 10 is arranged in the horizontal direction, the second main channel 10 is communicated with the first main channel 9, the first main channel 9 and the second main channel 10 are integrally annular, and the coolant flows through the first main channel 9 and the second main channel 10 by injecting the coolant into the cooling holes 3 and is used for cooling the center ring 7. In addition, the ratio of the coolant amount flowing inside the shutter passage 12 to the coolant amount flowing inside the main passage is (0.1-0.3): 1, and in particular 0.1, 0.2, 1, 0.3.

The operation of an embodiment of the radial clearance adjustment apparatus for a turbine engine according to the present invention will be described with reference to fig. 2 to 3:

as shown in fig. 2, when the turbine engine is in a hot start state, the centrifugal force acting on the turbine blades 5 and the casing 1 causes the radial dimension to increase, which results in narrowing the air passages 16 between the turbine blades 5 and the guide ring, and reducing the radial clearance, which may cause scraping between the turbine blades 5 and the guide ring. In this case, therefore, the coolant is injected from the cooling holes 3, flows through the first main channel 9 and the second main channel 10 of the central ring 7, cooling the central ring 7, and simultaneously enters the secondary channels 11 of the valve ring 8, cooling the valve ring 8; by properly designing the opening pressure of the check valve 14, the check valve 14 cannot be in the open state at this time, the valve passage 12 is closed, and the cooling air cannot flow into the valve passage 12 from the main passage. The cooling air quantity of the main channel and the secondary channel 11 is controlled to make the central ring 7 and the valve rings 8 on the two sides contract by the same amount, so that the turbine blades 5 can be ensured not to generate unnecessary scraping with the guide ring in a hot starting state.

As shown in fig. 3, when the turbine engine is in a steady operation state, after the standard opening pressure of the check valve 14 is reached, the check valve 14 is opened, the coolant is allowed to flow into the valve passage 12 from the main passage, typically, the ratio of the coolant amount in the valve passage 12 to the coolant amount in the main passage is 0.1-0.3, when the coolant amount in the main passage partially flows into the valve passage 12, the coolant amount for cooling in the main passage is reduced, the coolant amount for cooling in the valve passage 12 is increased, when the central ring 7 is radially increased relative to the hot start state, the valve ring 8 is radially contracted relative to the hot start state, the guide ring forms the outer castellation edge, the sealing effect is optimized, and the air leakage amount of the blade at this time is further reduced on the basis of ensuring reasonable radial clearance, and the operating efficiency of the turbine engine is optimized.

By way of illustration of various embodiments of the present radial clearance adjustment apparatus for a turbine engine, it can be seen that at least one or more of the following advantages may be realized by embodiments of the present radial clearance adjustment apparatus for a turbine engine:

1. the effective control of the air leakage of the turbine blade is realized, and the air leakage is reduced. The radial clearance adjusting device for the turbine engine provided by the invention has the advantages that through the design of the grading guide ring, the turbine can maintain enough radial clearance in the starting process, after stable work, the gas leakage can be reduced on the basis of maintaining the radial clearance of the grate tooth-shaped channel formed by the grading guide ring, the work efficiency of the turbine is greatly improved, and the technical problem of controlling the gas leakage quantity of the turbine blade at present is solved.

Finally, it should be noted that: the embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

The above examples are only intended to illustrate the technical solution of the present invention and not to limit it; although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that: modifications to the specific embodiments of the invention or equivalent substitutions for parts of the technical features may be made; without departing from the spirit of the present invention, it is intended to cover all aspects of the invention as defined by the appended claims.

Claims

1. A radial gap adjustment apparatus for a turbine engine, comprising:

the cooling device comprises a shell, a cooling device and a cooling device, wherein the shell is integrally annular, a guide groove is formed in the shell, and a cooling hole for introducing a coolant is formed in the shell;

a turbine blade of axial flow type as a whole, the turbine blade being installed at a central position inside the casing; and

wherein the guide ring further comprises:

the center ring is integrally arranged in the center of the guide ring, a main channel is arranged in the center ring, the main channel is communicated with the cooling holes, and the center ring is cooled by injecting a coolant into the cooling holes; and

the valve ring is arranged on two sides of the center ring, a secondary channel and a valve channel are arranged in the valve ring, the secondary channel and the valve channel are not communicated with each other, the secondary channel is communicated with the cooling hole, the valve ring is cooled by injecting a coolant into the cooling hole, and the valve channel is communicated with the bottom of the main channel.

2. The radial gap adjustment device for a turbine engine as set forth in claim 1, wherein said cooling hole opens in said housing and extends in a vertical direction all the way to the interior of said housing until communicating with the primary and secondary passages in said pilot ring.

3. The radial gap adjustment apparatus for a turbine engine according to claim 2, wherein the number of the cooling holes is one or more, and the coolant is cooling air or water.

4. The radial gap adjustment apparatus for a turbine engine as claimed in claim 1, wherein the guide groove has a cross-section of a T-shaped structure, the T-shaped structure including a horizontal portion integrally provided at an intermediate position inside the casing and a vertical portion provided below the horizontal portion and extending up to a bottom of the casing.

5. The radial clearance adjustment apparatus for a turbine engine according to claim 4, wherein two of the positioning rings are respectively disposed on both sides of the valve ring, and the two positioning rings do not correspond to the axial positions of the turbine blades, so that no scraping occurs between the turbine blades and the positioning rings;

the transversal structure of falling L of personally submitting of holding ring, the structure of falling L include the holding ring body that vertical direction set up and set up in the holding ring body top along the level to the locating surface, through the level to the locating surface makes the holding ring insert in the horizontal part of guide way, two final holding rings are close to the guide way sets up.

6. The radial gap adjusting apparatus for a turbine engine as set forth in claim 1, wherein the main passage is integrally provided inside a center ring, the main passage includes a first main passage and a second main passage provided below the first main passage, the first main passage is provided in a vertical direction and communicates with the cooling hole, the second main passage is provided in a horizontal direction and communicates with the first passage, the first main passage and the second main passage are integrally formed in a ring-like structure, and coolant flows through the first main passage and the second main passage by injecting the coolant into the cooling hole for cooling the center ring;

the secondary channel is integrally in an inverted L-shaped structure, the inverted L-shaped structure comprises a horizontal channel and a vertical channel arranged below the horizontal channel, the horizontal channel is communicated with the cooling hole, the vertical channel extends downwards in the valve ring all the time, and the coolant flows through the horizontal channel and the vertical channel in sequence and is used for cooling the valve ring by injecting the coolant into the cooling hole;

7. A radial gap adjusting apparatus for a turbine engine according to claim 6, wherein a coolant usage ratio of the inside of the shutter passage to the inside of the main passage is (0.1-0.3): 1.

8. the radial gap adjustment device for a turbine engine as claimed in claim 1, wherein the plurality of turbine blades are installed on the rotation shaft at the center of the bottom of the casing and located between the two rows of the guide blades and supported by bearings, and the plurality of turbine blades rotate together with the rotation shaft to form a rotating swept edge.

9. The radial gap adjustment device for a turbine engine as set forth in claim 1, wherein a heat insulating layer is further provided between the guide ring and the casing, the heat insulating layer insulating the guide ring relative to the casing so that the casing does not contract in the direction of the blades.