JPH0493592A - Rotary type regenerative heat exchanger - Google Patents

Abstract

PURPOSE:To prevent hot gas from directly jetting against a wall surface of a housing by a method wherein a guide member for changing the direction of flow of hot gas flowing from a branch pipe is installed inside the housing of hot gas. CONSTITUTION:A guide member 31 is supported inside a housing 5. A plate 33 is integrally formed at an upper part of the guide member 31 through a shaft 32. A groove 34 to which the plate 33 is loosely fitted is formed at an inner circumferential surface of a flat surface 5A of a housing 5. After ignition at a combustion device, jet hot gas driving a turbine is made to flow from the branch pipe 15 into the housing 5, strikes the guide member 31 to change the flow at nearly perpendicular direction and further flows toward openings at both ends of the housing 5. The gas flow does not directly impinge the inner circumferential surface of the housing 5, so that the temperature difference between the inner circumferential surface and the outer circumferential surface of the housing 5 is not increase and then it is possible to prevent a local heat stress from being generated at the housing 5. Although the housing 5 and the guide member 31 have different coefficients of thermal expansion, the plate 33 is fitted to the groove 34 with a predetermined clearance being left therein and then the variation in size caused by expansion is accommodated.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in a rotary regenerative heat exchanger used in a regenerative gas turbine or the like.

(Prior Art) The present applicant has filed Japanese Patent Application No. 1-288267 as a rotary regenerative heat exchanger for use in a regenerative gas turbine.

As shown in FIGS. 6 to 8, a semi-cylindrical low-temperature air housing 3 and a high-temperature gas housing 5 are placed with their flat surfaces facing each other, and the heat insulating covers 18 and 19 and the fastening strip plate 2 are assembled.
0 and 21 to form a housing assembly 50, and this housing assembly 50 is supported inside the gauging 1 via the elastic support member 28, while the openings at both ends of the housings 3 and 5 Seal seat surface 9
The rotating heat storage cores 6A and 6B are in sliding contact with the heat storage cores 6A and 9B, and the covers 7A and 7B that cover the opposite sides of the heat storage cores 6A and 6B have exhaust ports 16A and 16B at positions corresponding to the openings of the housing 5. is provided.

Branch pipes 14 and 15 are connected to the central portions of the side surfaces of the housings 3 and 5 in a direction perpendicular to the axis of the casing 1.

The high-temperature gas discharged from the turbine 4 flows into the housing 5 from the branch pipe 15, collides with the wall surface on the opposite side, and divides the flow into two at right angles.
After heating the heat storage cores 6A and 6B, the exhaust port 1
It is discharged to the outside from 6A and 16B.

On the other hand, compressed air from the compressor 2 passes through the gap between the gauging 1 and the housing 3, flows into the heat storage cores 6A and 6B through the gaps between the covers 7A and 7B and the heat storage cores 6A and 6B, and is heated by the heat storage cores 6A and 6B. Housing 3
and is supplied to the combustor 17 from the branch pipe 14.

(Problem to be solved by the invention) By the way, in this rotary regenerative heat exchanger, the jet of high-temperature combustion gas that drives the turbine 4 is ejected from the branch pipe 15 into the housing 5 and collides with the inner wall of the housing 5. Immediately after ignition of the housing 5, the temperature difference between the inner circumferential surface of the housing 5, which the jet impinges on, and the outer circumferential surface thereof becomes extremely large, creating an environment where large thermal stress is likely to occur locally.

On the other hand, the housing 5, on which the heat storage cores 6A and 6B are in sliding contact at both ends, is made of oxide-based ceramics such as LAS, which has a small coefficient of thermal expansion, in order to reduce the leakage of gas from these sliding contact parts. Oxide ceramics have a low bending strength of 3 to 6 kg/-2, so in order to ensure the strength against the above thermal stress, it is inevitable to have a thick structure, which increases the weight of the heat exchanger. This was a contributing factor.

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, it is an object of the present invention to prevent jets of high-temperature gas from directly colliding with the wall surface of a housing into which high-temperature gas is introduced.

(Means for Achieving the Object) For this purpose, the present invention accommodates a semi-cylindrical low-temperature air housing and a high-temperature gas housing inside a casing with their planar parts facing each other. A rotating heat storage type with a rotating heat storage core that slides in contact with the open end, a cover with an exhaust port that slides into contact with the rotating heat storage core on the opposite side of the housing, and a branch pipe connected to the center of the side of each housing. In the heat exchanger, a guide member is provided inside the high-temperature gas housing to change the flow direction of the high-temperature gas flowing from the branch pipe.

(Operation) The jet of high-temperature gas led from the branch pipe to the housing collides with the guide member, and is guided by the guide member to change the flow direction toward the heat storage core, so the high-temperature jet directly collides with the wall of the housing. This prevents excessive thermal stress from occurring in the housing.

Further, by changing the shape of the guide member to change the diffusion shape of the high-temperature gas, the distribution of thermal stress can be controlled in a preferable manner.

(Example) Embodiments of the present invention are shown in FIGS. 1 to 5.

In FIG. 1, reference numeral 5 denotes a semi-cylindrical housing for high temperature gas, with both ends open and a branch pipe 15 provided at the center of the side surface.

Inside the housing 5 is a guide member 3 with an arcuate cross section.
1 is supported opposite to the branch pipe 15.

The guide member 31 is made of high-strength ceramics such as S isN, and a shaft 32 is provided on the upper part of the guide member 31.
The plate 33 is integrally formed with the plate 33 interposed therebetween.

Further, a lever 34 into which the plate 33 is loosely fitted with a predetermined play is formed on the inner circumferential surface of the flat portion 5A of the housing 5.

Numeral 11 is a boss hole that engages with a boss of the low-temperature air housing, and 12 is a guide groove that similarly engages with a protrusion of the low-temperature air housing.

Note that the other configurations are the same as the previous example.

Next, the action will be explained.

After ignition in the combustor, the jet of high-temperature gas that drove the turbine flows into the housing 5 from the branch pipe 15 as shown by the arrow in the figure, collides with the guide member 31, turns the flow in a substantially perpendicular direction, and flows into both ends of the housing 5. Flows towards the opening.

In other words, since the jet flow flowing in from the branch pipe 15 does not directly collide with the inner circumferential surface of the housing 5, the temperature difference between the inner circumferential surface and the outer circumferential surface of the housing 5 does not become extremely large even immediately after ignition.
It is possible to prevent local thermal stress from occurring in the housing 5.

Therefore, the housing 5 can be made thinner than that of the conventional example, and thereby the weight can be reduced.

Note that although the housing 5 and the guide member 31 have different thermal expansion coefficients, the plate 33 is loosely fitted to the armature 34 with a predetermined play based on the difference in thermal expansion coefficient, so that the relative change in dimensions due to expansion is prevented. is absorbed within this range of play.

FIG. 2 shows another embodiment of the present invention, in which the guide member 31 is curved so that its horizontal cross section is arcuate. As a result, after the jet of high-temperature gas collides with the central part of the guide member 31, it is guided by the guide member 31 and diffuses radially as shown by the arrow in the figure, so that the temperature of the gas in the housing 5 is equalized. be able to.

3 to 5 show yet another embodiment of the present invention, in which the guide member 31 is supported on the housing 5 via a bayonet.

The bayonet includes a disc-shaped member 35 integrally formed on the upper part of the guide member 31 via a shaft 32, and a circular recess 36 formed on the inner peripheral surface of the flat part 5A of the housing 5 to hold the disc-shaped member 35. Consisting of

The disc-shaped member 35 has an outer claw 35A at 3w on the outer periphery.
Inner claws 36A are formed at three positions on the inner periphery of the opening of the recess 36. The outer claw 35A has a tip diameter slightly smaller than the inner diameter of the recess 36, and the inner claw 36A has a tip diameter larger than the diameter of the disc-shaped member 35, and the outer claw 35A has a diameter slightly smaller than the inner diameter of the recess 36.
It is formed to be smaller than the outer diameter of. Furthermore, since the outer claw 35A is located between the inner claws 36A, the disc-shaped member 3
The outer claw 35A and the inner claw 36 can be inserted into the recess 36.
The circumferential dimension of A is set.

A lock hole 37 is formed in the side surface of the disc-shaped member 35 in the horizontal direction, into which a rod 38 shown in FIG. 3 is fitted. Further, a horizontal hole extending from the recess 36 to the sealing surface 9B is formed in the flat part 5A of the housing 5, and when the guide member 31 is at a predetermined rotational position in the housing 5, this hole and the lock hole 37 are connected. It's supposed to match.

When attaching the guide member 31 to the housing 5, the outer claw 35A passes between the inner claws 36A so that the disc-shaped member 3
5 into the recess 36 of the housing 5, the guide member 31 is rotated to align the lock hole 37 with the hole in the housing 5 while overlapping the outer claw 35A on the inner claw 36A. Then, move the rod 38 from the sealing surface 9B to the flat part 5.
Insert it into the hole A and the lock hole 37 that is continuous thereto.

This restricts the rotation of the guide member 31.

Note that the rod 38 is also prevented from falling off by the sealing material attached to the sealing surface 9B.

By attaching the guide member 31 to the housing 5 via the bayonet in this manner, the attachment location of the guide member 31 can be set more freely.

(Effects of the Invention) As described above, the present invention includes a guide member inside the housing that changes the direction of the jet of high-temperature gas flowing into the housing from the inlet provided in the high-temperature gas housing toward the heat storage core. Since the jet of high-temperature gas does not directly collide with the inner peripheral surface of the housing, it is possible to prevent excessive thermal stress from being generated in a part of the housing immediately after ignition of the combustor.

This allows the wall thickness of the housing to be made thinner, thereby making it possible to reduce the weight of the housing.

Further, by changing the diffusion form of the high-temperature gas depending on the shape of the guide member, it is possible to control the distribution of thermal stress within the housing in a preferable manner.

[Brief explanation of the drawing]

Section 1 is an exploded perspective view of a housing and a guide member showing an embodiment of the present invention, FIG. 2 is a perspective view of a guide member showing another embodiment, and FIG. 3 is a perspective view of a guide member showing yet another embodiment. A perspective view, FIG. 4 is a cross-sectional view of a main part showing the engagement state of the guide member and the housing, and FIG.
It is an arrow view. Further, FIG. 6 is a sectional view of a rotary regenerative heat exchanger showing a conventional example, FIG. 7 is a view taken along the line BB in FIG. 6, and No. 80 is an exploded perspective view of the housing. 5... Housing, 5A... Plane part, 15... Branch pipe, 31... Guide member.

Claims (1)

[Claims] A semi-cylindrical low-temperature air housing and a high-temperature gas housing are housed inside the casing with their flat parts facing each other, and a heat storage core that slides and rotates on the open end of these housings, and a rotating heat storage core. In a rotary regenerative heat exchanger equipped with a cover forming an exhaust port that slides on the opposite side of the housing, and a branch pipe connected to the center of the side of each housing, high-temperature gas flows into the inside of the housing from the branch pipe. A rotary regenerative heat exchanger characterized in that it is equipped with a guide member that changes the direction of flow of high-temperature gas.