JP3564167B2 - Cooling structure of split ring - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a cooling structure for a split ring that forms a flow wall of a high-temperature working gas of a gas turbine.
[0002]
[Prior art]
FIG. 4 is a longitudinal sectional view of a gas turbine to which the present invention is applied. In the figure, 1 is a working gas passage, 2 is a working gas flow direction, 3 is a first-stage stationary blade, 4 is a second-stage stationary blade, and 5 is a first-stage moving blade provided between the two stationary blades. The stationary blades and the moving blades are sequentially and alternately arranged.
[0003]
In gas turbines, it is required to increase the temperature of working gas in order to increase turbine efficiency. At that time, in order to keep the temperature of the metal material of the wall surface forming the gas passage below the allowable temperature of the material, a hole for passing cooling air is provided in the member, and air is circulated through the hole to cool the member. Has been done.
[0004]
FIG. 5 is a longitudinal sectional view of a conventional wall cooling structure, and is a view at a position corresponding to a portion A in FIG. In the figure, 3 is a first stage stationary blade, 4 is a second stage stationary blade, and 5 is a first stage moving blade. Reference numeral 6 denotes a part called a split ring constituting a wall surface. This is a configuration in which a plurality of individual members that are divided on the circumference and form an arc shape are connected to each other to form a cylindrical wall surface. Reference numeral 7 denotes a plurality of cooling air holes provided in a member constituting the split ring, and is opened at a downstream end of the split ring member. Reference numeral 8 denotes an impingement plate (collision plate) provided on an outer peripheral portion of the split ring, 9 denotes a plurality of small holes provided in the impingement plate, and 10 denotes a flow of cooling air supplied by increasing the pressure from the outside. It is. Reference numeral 13 denotes a jaw for attaching the split ring 6 to the vehicle compartment, and 14 denotes an outer surface of the split ring.
[0005]
In this structure, when the cooling air 10 is supplied, the air collides with the impingement plate 8, and then blows out at a high speed from the small holes 9 of the impingement plate 8, and is blown to the outer surface 14 of the split ring to cool the split ring. . The air further passes through the plurality of cooling air holes 7 to cool the inside of the split ring, which is the original purpose. The cooling air flowing out of the air holes 7 mixes with the working gas and flows out of the gas turbine. The example described above relates to the cooling structure of the split ring adjacent to the first stage blade, but the other stages are provided with the same cooling structure as the above structure.
[0006]
[Problems to be solved by the invention]
In the above-described conventional structure, when the cooling air 10 is introduced into the outer peripheral portion of the split ring, a large amount of air leaks from the jaw 13 for attaching the split ring to the vehicle compartment and the gap between the divided surfaces on the circumference, and the cooling air Of the amount supplied to the outer peripheral portion of the split ring, the amount of air that effectively contributes to cooling through the cooling air hole 7, which is the original purpose, is reduced.
[0007]
SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks of the prior art and to reduce the amount of air leakage so that the split ring can be effectively cooled.
[0008]
[Means for Solving the Problems]
The present invention was to solve the above problems, the individual ring segment having an arcuate cross section having a shape divided in a plurality of locations on the cylindrical or peripheral conical gas turbine wall flows inside the hot working gas connect the components constitute a ring segment, the impingement plate having a plurality of small holes in the outer peripheral portion of the individual ring segment components provided on the individual ring segment structure member, respectively cooling air from the outside lead, in the cooling structure for cooling the cooling air is passed through the cooling air holes provided in the interior of the individual ring segment component split ring, the outer upper Kiko 's impingement plate, a plurality of the circumferential covering each a plurality of members having a portion in divided form mutually a cover having an arcuate cross-section connected by a slidable overlapping to form a chamber with the same cover and the ring segment component, and , Relates cooling structure of the split ring, characterized in that a tube for introducing cooling air from outside the chamber.
[0009]
[Action]
A chamber is formed by providing a cover, and cooling air from outside is introduced into the chamber. The air does not leak to the outside and enters the cooling air holes provided in the split ring to cool the split ring from the inside. Therefore, the cooling air is effectively used.
[0010]
【Example】
FIG. 1 is a longitudinal sectional view of a split ring cooling structure according to an embodiment of the present invention, FIG. 2 is a transverse sectional view of the embodiment (sectional view taken along the line BB in FIG. 1), and FIG. It is an expanded sectional view of a superposition part. FIG. 1 shows a portion corresponding to FIG. 5 (prior art drawing). In FIG. 1, reference numeral 11 denotes a cover provided so as to cover the outer periphery of the impingement plate 8 provided on each of the split ring constituent members. A chamber is formed between the cover and the split ring component, and an impingement plate 8 is provided in the chamber. Reference numeral 12 denotes a pipe for supplying cooling air from the outside to the chamber, through which the cooling air 10 flows. 13 is a jaw for attaching the split ring 6 to the vehicle compartment, and 14 is an outer surface of the split ring. In FIG. 2, reference numeral 15 denotes a dividing portion on the circumference of the dividing ring 6, which does not restrict thermal expansion. Reference numeral 16 denotes an overlapping portion of the cover 11, which is slidable with each other. Reference numeral 17 denotes a divided portion of the impingement plate for preventing the thermal expansion from being restricted.
[0011]
In the structure of the present embodiment, the cooling air flows into the inside of the cover 11 via the pipe 12. The air that has flowed into the ring is injected into the outer surface 14 of the split ring through the small holes 9 and the split portion 17 of the impingement plate, and after cooling the outer surface of the split ring, passes through the cooling air holes 7 to cool the inside of the split ring. Cools and flows out downstream. In this structure, since the cover 11 is provided, the cooling air does not leak wastefully through the jaws 13 and the split portions 15 of the split ring, and the split ring 6 can be effectively cooled. . Since the cover 11 is provided with the overlapping portion 16, thermal stress caused by thermal expansion, deformation of the split ring, and the like can be reduced. Further, since the impingement plate 8 is provided with the divided portion 17 and is abutted with a slight gap, thermal stress can be prevented. This gap contributes to the ejection of the cooling air similarly to the small holes 9.
[0012]
As described in detail above, the structure of this embodiment can provide a cover without generating a large thermal stress in the split ring, and as a result, it is possible to reduce unnecessary air leakage to the surroundings. Accordingly, the split ring can be cooled, the thermal efficiency of the gas turbine can be improved, and the life of the split ring can be extended. The above-described cooling structure, and its operation and effects are the same for other stages.
[0013]
【The invention's effect】
In the cooling structure for a split ring according to the present invention, a plurality of members having a shape divided at a plurality of locations on the circumference are overlapped with each other outside the individual split ring constituent members constituting the split ring. A cover having an arc-shaped cross section connected by joining is formed, a chamber is formed by the cover and the above-mentioned split ring constituting member, and a pipe for introducing cooling air from the outside to the chamber is provided. There is no unnecessary leakage, and the split ring can be cooled effectively. Also, the cooling member is not damaged by thermal stress.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of a split ring cooling structure according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of the embodiment (a cross-sectional view taken along line BB of FIG. 1).
FIG. 3 is an enlarged cross-sectional view of an overlapping portion of the cover according to the embodiment.
FIG. 4 is a longitudinal sectional view of a gas turbine to which the present invention is applied.
FIG. 5 is a longitudinal sectional view of a conventional wall cooling structure (a view at a position corresponding to a portion A in FIG. 4).
[Explanation of symbols]
REFERENCE SIGNS LIST 1 working gas passage 2 flow direction 3 first stage stationary blade 4 second stage stationary blade 5 first stage moving blade 6 split ring 7 cooling air hole 8 impingement plate 9 small hole 10 cooling air flow 11 cover 12 pipe 13 jaw 14 split ring Outer surface 15 Dividing portion of split ring 16 Overlap portion of cover 17 Dividing portion of impingement plate

Claims (1)

Connect the individual ring segment component having an arcuate cross-section of the divided shape at a plurality of locations of cylindrical or its periphery a conical gas turbine wall flow within the hot working gas constituting the split ring, the provided impingement plate having a plurality of small holes in the outer peripheral portion of each of the split ring components, to the individual ring segment structure member guides each cooling air from the outside, the individual ring segment component the cooling air of the cooling structure for cooling the ring segment by circulating the cooling air holes provided therein, the outer upper Kiko 's impingement plate, a plurality of members having a divided form at a plurality of points on the circumference cross each covered with a cover having an arcuate cross-section connected by a slidable superposition to form a chamber with the same cover and the ring segment component, and is provided with a tube for introducing cooling air from outside into the same room Cooling structure of the split ring, characterized in that.

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