JPS58102031A - Supporting structure of gas turbine combustor - Google Patents

Abstract

PURPOSE:To improve the cooling effect of a supporting base member and prevent broken pieces of a cylindrical spring member from mixing into combustion gas by a structure wherein the cylindrical spring member, which has an upstream swollen-out part comprising a plurality of longitudinal reeds and a center swollen-out part, is fixed by inserting itself onto the front combustion chamber supporting base member, the upstream end of which is expanded outward. CONSTITUTION:A bellmouth-curved plate part 32 is provided at the upstream part of a cylindrical supporting base member 21' continuously connected to a front combustion chamber 7. A cylindrical spring member 37, which is made of heat resisting spring steel and at the downstream end of which a bellmouth-tapered tube part 43 is formed, is fixed by inserting itself onto a supporting base member 21'. The band-like swollen-out part 38 comprising a large number of longitudinal reeds 38' is formed at the upstream end of the spring member 37 and a swollen-out part 39, the swollen-out amount of which is smaller than that of the swollen-out part 38, is also formed at the center of the spring member 37. Owing to the structure as described above, the spacings between a combustion chamber wall 30 and the upstream end of the supporting base member 21' and between the wall 30 and the downstream end of the spring member 37 become narrow, resulting in permitting the broken pieces of the reeds 38 to fall down in the route as indicated with the arrow (b), not being allowed to pass through the tapered tube part 43 as indicated with the arrow (a) and preventing the broken pieces of the reeds 38 from mixing into combustion gas. In addition, owing to the space 36 formed by the swollen-out part 39, the cooling effect of the base member 21' is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a support part for a gas turbine, and more particularly, to a support part for a gas turbine combustor that eliminates the possibility that even if a member of the support part is damaged, its fragments will not be mixed into the combustion gas flow. It's about structure.

The combustor of a gas turbine has the role of generating combustion gas as a working fluid and guiding this gas to the gas turbine rotor blades. FIG. 1 is a sectional view of a low NOx type combustor. Generally, a combustor is roughly divided into an inner cylinder 2 that generates snoring gas, a transition cylinder 3 that guides the combustion gas to the moving X section, and a fuel nozzle 6.
The above-mentioned members are housed in the high pressure chamber of the gas turbine by an outer cylinder 4 and a front cover 5.

As a feature of the low NOx type combustor shown in Fig. 1, the inner cylinder 2
It consists of a crystal 1j combustion chamber 7 and a main combustion chamber 8.

#! 1. The main purpose of the combustion chamber 7 is to improve mixing of air and fuel to perform diluted combustion, and functions as follows. The air flow 11 pressurized by compression [10 is
It flows along the outer surface of the inner cylinder 2 and a part of the annulus between the inner cylinder 2 and the outer cylinder 4 toward the head side of the inner cylinder 2 (left side in the figure). Approximately half of the airflow 11 is covered by the turbulator 14. First radial swivel 17. Or the second radial swivel 18
Via Akira 1. It flows into the combustion chamber 7, mixes with the sprayed fuel 9, and burns it.

On the other hand, the main combustion chamber 8 functions as if it were inactive, with the main purpose of completely burning the components left unburned in the sub-combustion chamber 7 to generate combustion gas #L16 at a predetermined temperature. For convenience of explanation, with respect to the flow direction of the combustion gas flow 16, the upstream all (left side in the figure) is referred to as the upstream side, and the downstream side (right side in the figure) is referred to as lower fL@.

An air hole 15 is provided on the upstream side of the main combustion chamber 8, and air for promoting combustion is also supplied from here. The dilution air hole 12 is provided to lower the combustion gas to a predetermined temperature, and 10 to 15% of the total supply air flow rate is sent through the dilution air hole 12 described above.

The combustion gas flow 16 adjusted to a predetermined temperature flows through the transition piece 3 and is guided to the turbine section 13 to generate power.

Generally, the auxiliary combustion chamber 7ri is formed in the shape of a cylinder with a small diameter, and is attached to the head of the rear combustion chamber, which is formed in the shape of a cylinder with a large diameter. The rear combustion chamber 8, which is formed into a large-diameter cylindrical shape, acts as a main combustion chamber.

The head combustion □ chamber described above is attached to the rear combustion chamber 8 by forming a tapered tubular enlarged portion 19 at its downstream end. An enlarged view of the mounting portion A is shown in FIG. 2.

As mentioned above, Rizan, in which the auxiliary combustion chamber 7 and the main combustion chamber 8 are divided into a small-diameter cylindrical head combustion chamber and a large-diameter cylindrical rear combustion chamber, are mainly maintained. Due to consideration for improving sex. FIG. 3 is an external perspective view of the auxiliary combustion chamber 7, that is, the small-diameter head combustion chamber.

As shown in FIG. 2, which shows a cross section, a cylindrical support base material 21 is integrally connected to the downstream end of the Taber tubular enlarged portion 19.

A cylindrical member 24 formed separately from the support base material 21 is externally fitted and fixed to the cylindrical support base material 21, and a large number of support leaf springs are attached to the upstream end of the cylindrical member 24. 22.22 is formed like a defect.

(See Fig. 3) A large number of notches 26, 26 are provided on the upstream end side of the cylindrical member 24, and the portion sandwiched between two adjacent notches forms the support plate spring 22. A small hole 27 is bored at the end of the groove 26 to relieve stress concentration.

The support plate spring 22 formed as described above is shown in cross-sectional view (
As shown in FIG. 2), an arcuate portion 23 is formed that is convex toward the outside.

Since it is convex toward the outside, it naturally has a concave shape toward the inside, but for convenience of explanation, hereinafter, for a cylindrical member, convex toward the outside II and concave toward the inside will simply be referred to as convex. Say.

Reference numerals 28 and 28 shown in the external view (FIG. 3) are spot welds for fixing the cylindrical member 24 to the supporting base material.

(See Fig. 2) A cylindrical support pedestal 31 is fixed to the inner peripheral surface of a large-diameter cylindrical rear combustion chamber wall 30 forming the main combustion chamber,
The head combustion chamber 7 to which the support plate spring 23 is attached is press-fitted into the support pedestal 31 so that the arcuate portion 23 of the support plate spring is elastically pressed into contact with the support base 31.

The support structure of the conventional gas turbine combustion chamber configured as described above has the following problems: (1) When the support leaf spring 22 is damaged, there is a risk that its fragments may be mixed into the combustion gas flow; (2) There are two technical problems: the aforementioned support structure is not sufficiently cooled.

If cooling is insufficient, the components of this support structure are likely to overheat, reducing their mechanical strength and increasing the risk of breakage.

The support part of the head combustion chamber shown in FIG. 2 corresponds to the outlet of the auxiliary combustion chamber and is a part where combustion is rapidly promoted, so it easily becomes high temperature. Furthermore, since the enlarged portion 19 is tapered open, the mainstream gas is drawn in, and a stagnation portion 42 is formed, so that the metal temperature in this vicinity tends to increase.

When the components of the support structure become overheated and lose their strength,
The root part 2 of the support plate screw 22 is subjected to a large stress.
There is a large risk of breakage.

When the support plate spring 22 breaks, the IJ air flow 29 indicated by the arrow increases, and the debris is swept downstream and flows into the turbine rotor blade (not shown) along with the combustion gas flow, resulting in a serious
There is a high risk of causing secondary damage. There is also a risk that debris may fall off upstream and enter the combustion gas stream through the second radial swirler 18.

An object of the present invention is to make it easy to effectively cool the mounting part of the head combustion chamber of a gas turbine, and to prevent the possibility that even if a component is damaged, its fragments will be mixed into the combustion gas flow. There is no need to provide a support structure for the gas turbine combustor.

To achieve the above object, the present invention provides a structure that facilitates impingement cooling and film cooling of the supporting base material of the mounting part by cooling air, and furthermore, the cooling air flow path allows debris to pass through. The present invention was completed by researching a support structure that would be free from any risk. In the support structure of a gas turbine combustor, a cylindrical spring member is fitted onto a cylindrical support base material that is integrally connected to the enlarged portion of the downstream end of the head combustion chamber, and the cylindrical support structure is Expanding the upstream end of the base material and the downstream end of the cylindrical spring member into a trumpet shape,
Two band-like bulges are formed in the shape of expanding the cylindrical radius at two places near the upstream side and near the center of the cylindrical spring member, and a large number of cuts are formed in the longitudinal direction from the upstream end. 1. A large number of arcuate tongue pieces are formed by inserting the whole part, and the cylindrical supporting base material is placed in a place where it faces the bulge formed in the center of the cylindrical neck member. It is characterized by having a scoop-shaped recess.

Next, one embodiment of the present invention will be described with reference to FIGS. 4 to 6.

Fig. 4 shows a cross section of the support structure, and corresponds to Fig. 2 in a conventional structure, Fig. 5 is a perspective view of the support structure extracted from the above, and Fig. 6 is a quarter m$I. This is a perspective view.

In the above three drawings, the small diameter cylindrical head, part combustion chamber 7, and enlarged part 1 are shown with the same numbers as in Fig. 2.
9, the large diameter cylindrical rear combustion chamber wall 30, and the support pedestal 31 are the same components as in the conventional structure.

The cylindrical support base material 21' is a component similar to the support base material in the conventional structure, but the support base material 21' in the structure of the present invention has its upstream end expanded into a curved plate part. 3
form 2. The support base material 21' is integrally connected to the small-diameter cylindrical head combustion chamber 7 via the enlarged portion 19.

A cylindrical nail member 3 that fits onto the support base material 21' mentioned above.
7 is made of heat-resistant spring steel, and its downstream end is widened into a trumpet shape to form a hollow tube portion 43.

Also on the upstream side of the tapered pipe portion 43, spot welding is performed at a portion where the cylindrical spring member 37 and the cylindrical support base material 21' are in contact with each other to fix them to each other.

(See Fig. 4) The cross section near the upstream end of the cylindrical cutout member 37 is shaped like a drum with an arcuate bulge.
A band-shaped bulge 38 is formed over the entire circumference. Similarly,
There is also a small band-shaped bulge 3 in the center as well as the bulge 38 mentioned above.
form 9.

As shown in FIGS. 5 and 6, the cylindrical spring member 37 has a large number of cuts 26', 2 from its upstream end.
A large number of tongue pieces 38', 38 are provided at equal intervals in the longitudinal direction.
' to form.

- As mentioned above, since the upstream end portion of this cylindrical notch member 37 is bulged like a drum body, each tongue piece sandwiched between the notches 26' and 26' has an arc-shaped shape. Leaf springs 38', 38' are formed.

The depth of the cuts 26' and 26' is such that it covers most of the bulge on the upstream end side of the front ml.

(See FIGS. 4 and 5) An annular groove-shaped recess 34 is formed in the cylindrical support base material 21' so as to face the small bulge 39 formed in the center of the cylindrical spring member 37. . Thereby, an annular space 36 is formed between the cylindrical spring member 37 and the cylindrical support base material 21'.

The combustor support structure according to the present invention is configured as described above, and the upstream end of the cylindrical support base material 21' is widened, and the distance between the inward direction of the large-diameter cylindrical rear combustion chamber wall 30 is set. is narrowed, and the downstream end of the cylindrical spring member 37 is also widened to narrow the distance from the inner surface of the rear combustion chamber wall 30. Therefore, even if the arc-shaped leaf spring 38' breaks from the base, there is no risk that the fragments will flow downstream as shown by arrow A and get mixed into the combustion gas flow. There is also no risk of it falling upstream and entering the combustion gas stream through the second radial swirler 18.

The combustor support structure according to the present invention has a ring-shaped bulge formed in the center of the cylindrical spring member and an annular groove-shaped recess formed in the cylindrical support base material. Since a space (the space 36 in the above embodiment) is formed, it is easy to effectively cool the support base material by introducing cooling air into this space in a manner similar to that of a gap.

In the embodiment shown in FIGS. 4 to 6, the cylindrical spring member 3
Cooling air holes 4 are provided in a band-shaped bulge 39 formed in the center of 7.
0, and a cooling air hole 33 is also bored on the upstream slope of the annular groove-shaped recess 34 formed in the cylindrical support base material 21'. The cooling air holes 33 are arranged obliquely so as to form as small an angle as possible with respect to the cylindrical surface of the cylindrical support base material 21'.

The above oblique angle may be set to zero. 44 is a cooling air hole bored in the large diameter cylindrical rear combustion chamber wall 30.

When the cooling air holes are provided as described above, the rear combustion chamber wall 30
A part of the pressure air guided to the outside of the cooling air hole 44
It flows into the cylindrical spring member 37 at almost right angles and prevents impingement cooling, and further passes through the cooling holes 40 formed in the cylindrical spring member 37 and enters the cylindrical support base material 21'. impingement cooling occurs when it hits a corner, and after flowing through the annular space 36 and effectively cooling the cylindrical support base material 21'', it flows into the combustion gas flow side through the cooling air hole 33. Since the cooling air holes 33 obliquely intersect with the cylindrical surface of the cylindrical support base material 21', they are not resisted by the vortex direction of the stagnation part 42 of the combustion gas flow, and are not forced into the inner surface of the cylindrical support base material 21'. Effective film cooling is achieved by forming a trailing flow.

Next, an example of Kj processing to which the present invention is applied will be explained with reference to FIG. The difference from the embodiment shown in FIG. 4 is that the position of the diaphragm-shaped bulge 38' of the cylindrical spring member 37' has been moved slightly toward the center, and The end 46 is brought into contact with the supporting base material 21'', and the upstream end of the supporting base material 21'' is folded back and extended into an IJ shape to form the upstream side of the large diameter cylindrical rear combustion wall 30'. The curved portion supporting portion 48t is configured to hold the outer periphery of the main chamber supporting end 50.

With the above configuration, the arc-shaped leaf springs 38' arranged in a row on the upstream side of the cylindrical spring member 37' do not have a cantilever shape, but on both sides thereof, that is, at the upstream end 46 of the cylindrical spring member 37'.
Since it comes into contact with the supporting base material 21'' at two locations, ie, the central protrusion location 46, strong support can be achieved without applying large stress to the arc-shaped leaf spring 38'.

Also, since the upstream end of the support base material 37' is formed into a U-shape to hold the main chamber support end 50 of the rear combustion chamber wall 30', in the unlikely event that the arcuate leaf spring 38' is damaged. In this case, it is possible to more reliably prevent the fragments from falling to the upstream side. 4
7 is a ventilation hole for cooling/combustion auxiliary air. In this modification, in order to form the main chamber support end 50 on the rear combustion chamber wall 30', the rear combustion chamber wall 30' has a double cylindrical structure, and the upstream end of the inner cylinder 53 is slightly inserted into the outer cylinder 52. Make it stick out. The support gap 51 is a gap provided to release thermal expansion and contraction.

As explained above, in the support structure for a gas turbine combustor according to the present invention, a cylindrical spring member is externally fitted and fixed to the cylindrical support base material connected to the head combustion chamber, and the upstream end thereof A band-shaped bulge is formed in the central part and the downstream end thereof is expanded, and the upstream end of the cylindrical support base material is expanded, and the central part of the cylindrical spring member is expanded. A ring-shaped groove-shaped recess is formed in the cylindrical support base material so as to face the bulge formed in the cylindrical spring member, and a plurality of longitudinal cuts are provided at the upstream end of the cylindrical spring member. By forming the arcuate tongue piece, cooling of the head combustion chamber of the gas turbine is facilitated, and even if a component is damaged, there is no risk that its fragments will be mixed into the combustion gas flow. There is no

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing the general configuration of a gas turbine combustor, FIG. 2 is a cross-sectional view showing the support structure of a conventional gas turbine combustor, FIG. 3 is a perspective view thereof, and FIG. 4 is the invention of the present invention. 5 is a perspective view of the same, FIG. 6 is an exploded perspective view of the same, and FIG. 7 is a support structure of a gas turbine combustor in a modified example of the present invention. FIG. 3 is a cross-sectional view of the structure. 7... A combustion chamber formed by a small-diameter head combustion chamber, 8... Main combustion chamber formed by a large-diameter rear combustion chamber, 21.21', 21''... Support base material , 26°26'... cut, 32... expanded curved plate part, 33
゜40.44... Cooling air hole, 34... Annular groove-shaped recess, 37.37'... Cylindrical spring member, 38.3
8'...Nine arc-shaped plate springs formed by band-shaped bulges, 39...Small band-shaped bulges, 43...Nine expanded Taber pipe parts. Agent Patent Attorney Masami Akimoto

Claims (1)

[Scope of Claims] 1. In a support structure for a gas turbine combustor in which a small-diameter cylindrical head combustion chamber is attached to a large-diameter cylindrical rear combustion chamber, a cylindrical-shaped combustion chamber connected to the head combustion chamber A cylindrical spring member is externally fitted onto the support base material, and the Fhim vicinity thereof is fixed to each other, and the upstream end of the cylindrical support base material and the lower tM, 5ill ends of the cylindrical spring member are The cylindrical spring member is expanded into a tapered tube shape, and band-shaped bulges are formed at two locations near the upstream side and near the center of the niT it cylindrical spring member, and a plurality of longitudinal bulges are formed at the upstream end of the cylindrical spring member. Cuts are made to form a plurality of arcuate tongue pieces, and the cylindrical support base material is placed at a location where the cylindrical support base material faces the bulge in the center of the cylindrical spring member. A support structure for a gas turbine combustor, characterized in that a concave portion is formed along the periphery. 2. A cooling air hole for impingement cooling the cylindrical support base material facing the cylindrical support base material is bored in the band-shaped bulge formed in the center of the cylindrical spring member, and A cooling air hole is bored in the annular groove-shaped recess, and
By making the direction of the cooling air hole bored in the cylindrical support base material obliquely intersect with the cylindrical surface of the cylindrical support base material, the cooling air flow passing through the cooling air hole is directed in the same direction as the combustion air flow. The gas turbine according to claim 1, characterized in that the cylindrical support base material can be film-cooled by causing the flow to flow in a direction along the inner surface of the cylindrical support base material. Combustor support structure.