JPH05179994A - Gas turbine engine - Google Patents

Abstract

PURPOSE:To prevent the temperature of intake air from rising by providing a heat insulating material on a defuser plate surface. CONSTITUTION:The flange part 52 of a turbine scroll 36 and the flange part 48 of a nozzle plate 46 are fixed by a radial direction bolt 56. An annular projection 66 is formed while it is extended from a defuser plate 24 in an axial direction at a slight interval from the top part of the bolt 56. A recessed part 68 is formed on the surface of the defuser plate 24 facing to the turbine scroll 36 from the annular projection 66 to a top end part 24-1. A heat insulating material 70 is filled into the recessed part 68. Intake air passing a defuser 25 is isolated from heat of the turbine scroll 36, and it is thus possible to measure the correct temperature of intake air by a temperature sensor provided downstream from the defuser 25.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas turbine engine, and more particularly to a heat insulating structure between a turbine scroll and a diffuser plate.

[0002]

2. Description of the Related Art In a gas turbine engine, a compressor is arranged in a front housing, and a diffuser plate is arranged so as to face the front housing.
A diffuser is arranged between the front housing and the diffuser plate, the flange portion of the nozzle plate is fixed to the diffuser plate with bolts in the axial direction, and the flange portion of the nozzle plate and the flange portion of the turbine scroll are fixed with radial bolts. It has a structure. Since the turbine scroll is located close to the diffuser plate, the air flowing into the combustor that has passed through the diffuser is affected by the radiant heat of the hot combustion gas in the turbine scroll. In the gas turbine engine, when the fuel supply amount is determined according to the temperature of the compressor outlet air, the temperature of the compressor outlet air is measured by a temperature sensor provided in the intake passage immediately downstream of the diffuser. However, since the compressor outlet air flowing out of the diffuser is affected by the radiant heat from the turbine scroll, the temperature sensor provided downstream of the diffuser cannot accurately grasp the temperature of the compressor outlet air, which affects engine control. give. Therefore, it is conceivable to dispose a heat insulating material between the turbine scroll and the diffuser plate in order to thermally block the turbine scroll and the diffuser plate. For example, Japanese Utility Model Laid-Open No. 2-46031 discloses an axial flow turbine in which a heat insulating material is arranged on an outer wall surface which defines a passage for combustion gas from a combustor to a turbine.

[0003]

In the prior art, in an axial turbine, a heat insulating material is formed on an outer wall surface that defines a combustion gas passage from the combustor to the turbine. Since this configuration does not directly expose the high temperature of the combustion gas to the air from the diffuser, it is possible to prevent the compressor outlet air flowing through the diffuser from being affected by the high temperature of the combustion gas. However, in the structure of the prior art, since the heat insulating material is extended only to the same position in the radial direction as the diffuser, the downstream side of the diffuser is affected by the high temperature of the combustion gas, and the temperature sensor installed downstream of the diffuser ensures accurate intake. There was a possibility that the temperature could not be detected.

An object of the present invention is to provide a structure capable of eliminating the influence of heat on the compressor outlet air in the diffuser due to the high temperature of the combustion gas.

[0005]

According to the present invention, in the structure in which the flange portion of the nozzle plate and the flange portion of the turbine scroll are fixed to the diffuser plate of the gas turbine engine by the bolts arranged in the radial direction, the bolts are provided. Slightly outward from the head of the
An annular protrusion extending toward the turbine scroll is formed on the diffuser plate, and an insulating material is held in an annular recess formed on the diffuser plate surface facing the turbine scroll from the protrusion to the outer peripheral end of the diffuser plate. A gas turbine engine is provided.

[0006]

The radiant heat from the combustion gas passing through the turbine scroll is blocked by the heat insulating material extending to the outer peripheral end of the diffuser, the temperature rise of the compressor outlet air downstream of the diffuser is prevented, and the temperature sensor is provided downstream of the diffuser. Even if it is provided, the temperature of the compressor outlet air can be detected with high accuracy, and an accurate amount of fuel can be supplied.

[0007]

1, a rotary shaft 10 is supported by a bearing housing 12 by a radial bearing 14 and a thrust bearing 16. Compressor impeller 18 on rotating shaft 10
And the turbine rotor 20 are provided back to back.
The compressor impeller 18 is located inside the front housing 22, and a diffuser plate 24 is arranged between the compressor impeller 18 and the turbine rotor 20. The diffuser plate 24 has an outer peripheral end 24-1.
Is curved and finally extends in a direction parallel to the axis of the rotating shaft. A diffuser 25 fixed on the diffuser plate 24 extends toward the front housing 22. A combustor housing 26 is joined to the front housing 22. A combustor 28 is arranged in the combustor housing 26, a fuel nozzle 30 is arranged at an upper end of the combustor 28, and a spark plug 32 is attached to a side surface of the combustor 28. The lower end of the combustor 28 extends to the turbine scroll 36, and the turbine scroll 36 opens to the turbine rotor 20. A turbine shroud 40 extends to the exhaust pipe 42.

In FIG. 2, the turbine scroll 36 is connected at its inner circumference to an annular nozzle plate 46,
The nozzle vanes 50 are fixed to the nozzle plate 46 at equal intervals in the circumferential direction. In FIG. 3, the turbine scroll 36 includes an annular flange portion 52, and the annular flange portion 52
Are fixed to the flange portion 48 of the nozzle plate 46 by radial bolts 56. The radial direction bolts 56 are provided at a plurality of positions at intervals in the circumferential direction. Further, as shown in FIG. 2, the flange portion 48 of the nozzle plate 46 is provided with the axial bolt 6 from the front of the front housing 22.
2 is screwed in via the diffuser plate 24, whereby the front housing 22, the diffuser plate 24, and the turbine scroll 36 are assembled together.

In FIG. 3, the diffuser plate 24
Forms an annular projection 66 extending toward the turbine scroll 36 at a position on the outer periphery of the turbine scroll 36, extending somewhat in the radial direction from the head of the radial bolt 56 in a direction parallel to the axial direction. The annular projection 66 extends between the projection 66 and the curved outer peripheral end portion 24-1 of the diffuser plate 24.
An annular recess 68 is formed on the surface facing 6 and the recess 68
The heat insulating material 70 is filled in.

At the time of assembling, the flange portion 52 of the turbine scroll 36 fixed to the flange portion 48 of the nozzle plate 46 by the radial bolts 56 is axially introduced to the outer periphery of the turbine rotor 20 from the front housing 22 side. By inserting the axial bolt 62 through the diffuser plate 24 and screwing it into the flange portion 48 of the nozzle plate 46, the front housing 22 and
The diffuser plate 24, the nozzle plate 46,
Assembly with the turbine scroll 36 is performed. The contact area of the contact portion 63 between the nozzle plate 46 and the diffuser plate 24 at the time of assembly is minimized to eliminate the influence of heat transfer to the diffuser plate 24 side.

The air compressed by the compressor impeller 18 is introduced into the combustor 28 through a passage 74 between the diffuser 25 and an intake passage 73 downstream of the diffuser 25 and the inside of the housing 26 around the combustor, and the combustion is performed. The combustion gas obtained by the combustion in the vessel is introduced into the turbine rotor 20 via the nozzle vanes 50 and discharged to the exhaust pipe 42. Since the high-temperature combustion gas passes through the turbine scroll 36, the turbine scroll 36 becomes hot and the diffuser plate 24 receives radiant heat from the turbine scroll 36. Since the recess 68 formed on the surface of the diffuser plate 24 facing the turbine scroll 36 is filled with the heat insulating material 70 up to the outer peripheral end portion 24-1 of the diffuser plate 24, after passing through the diffuser 25. The influence of radiant heat on the compressor outlet air is blocked, and the temperature of the compressor outlet air can be accurately measured by the temperature sensor arranged at the position P, for example, in the intake passage 73 on the rear surface of the diffuser plate 24 downstream of the diffuser 25. Therefore, an accurate fuel amount can be calculated using the outlet temperature of the diffuser.

The compressor outlet air after passing through the diffuser 25 is introduced into the combustor 28 through the passage 74 and is used for combustion. This compressor outlet air is passed through the passage 74.
When passing through, the outside of the turbine scroll 36 through which the hot combustion gas flows can be cooled, and the turbine scroll 36 can be prevented from being overheated by the combustion gas.

[0013]

EFFECTS OF THE INVENTION An annular projection is formed on a diffuser plate at a distance from a head of a radial bolt to a radial outer side and extends toward a turbine scroll, and the turbine scroll extends from the projection to an outer peripheral end portion of the diffuser plate. By holding the heat insulating material in the annular recess formed on the surface of the diffuser plate facing, the radiant heat from the turbine scroll blocks the effect of heat on the compressor outlet air passing through the diffuser, and Since the temperature of the compressor outlet air can be known accurately by the temperature sensor provided in the intake passage on the back surface of the diffuser plate on the downstream side, highly accurate fuel supply amount control can be realized.

Although the radial bolts 56 may be loosened due to the heat load of the engine, vibration, or some other cause, the bolts 56 are prevented from falling off further by the protrusions 66, and are caught in the rotating portion. There is no fear.
The protrusion 66 functions as a reinforcing member and has an effect of preventing thermal deformation of the diffuser plate due to thermal fatigue.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a gas turbine engine of the present invention.

FIG. 2 is an enlarged view of a portion indicated by A in FIG.

FIG. 3 is an enlarged view of a portion indicated by B in FIG.

[Explanation of symbols]

 10 ... Rotating shaft 18 ... Compressor impeller 20 ... Turbine rotor 24 ... Diffuser plate 25 ... Diffuser 26 ... Combustor housing 28 ... Combustor 32 ... Spark plug 36 ... Turbine scroll 46 ... Nozzle plate 50 ... Nozzle vane 56 ... Radial bolt 62 ... Axial bolt 66 ... Protrusion 68 ... Recess 70 ... Insulation material

Claims (1)

[Claims] 1. A structure in which a flange portion of a nozzle plate and a flange portion of a turbine scroll are fixed to a diffuser plate of a gas turbine engine by radial bolts, and the turbine is slightly separated from the head portion of the bolts radially outward. An annular protrusion extending toward the scroll is formed on the diffuser plate, and an insulating material is retained in an annular recess formed on the diffuser plate surface facing the turbine scroll from the protrusion to the outer peripheral end of the diffuser plate. Gas turbine engine characterized by.