Combustion chamber arrangement

Abstract

A combustion chamber arrangement including an outer annular wall and an inner annular wall spaced from the outer annular wall. The inner annular wall includes a plurality of tiles. At least one of the tiles is secured to the outer annular wall by at least one stud and a cooperating nut. Each stud includes a head and a threaded portion extending from the head. The threaded portions extend through an aperture in the tile and an aperture in the outer annular wall. The head includes a plurality of spacers to space the head from an inner surface of the tile. An associated washer either has an aperture extending radially there-through or a slot extending radially along one of the surfaces of the washer to supply coolant over the stud or the space between the inner annular wall and the outer annular wall is arranged to supply coolant over the stud.

1 . A combustion chamber arrangement comprising an outer annular wall and an inner annular wall spaced from the outer annular wall, the inner annular wall comprising a plurality of tiles, at least one of the tiles being secured to the outer annular wall by at least one stud and a cooperating nut, the at least one stud comprising a head and a threaded portion extending from the head, the threaded portion of the at least one stud extending through an aperture in the at least one tile and an aperture in the outer annular wall, wherein the head comprising a plurality of spacers to space the head from an inner surface of the at least one tile, the spacers being circumferentially spaced around the head of the stud, the head, the threaded portion and the spacers of the at least one stud being integral. 
     
     
         2 . A combustion chamber as claimed in  claim 1  wherein each tile is secured to the outer annular wall by at least one stud and a cooperating nut, the at least one stud of each tile comprising a head and a threaded portion extending from the head, the threaded portion of the at least one stud extending through an aperture in the at least one tile and an aperture in the outer annular wall, wherein the head of the at least one stud of each tile comprising a plurality of spacers to space the head from the inner surface of the respective tile, the spacers being circumferentially spaced around the head of the stud of each tile, the head, the threaded portion and the spacers of the at least one stud of each tile being integral. 
     
     
         3 . A combustion chamber as claimed in  claim 2  wherein each tile has a plurality of studs, each stud having a cooperating nut, each stud comprising a head and a threaded portion extending from the head, the threaded portion of each stud extending through a respective aperture in the at least one tile and a respective aperture in the outer annular wall, wherein the head of each stud comprising a plurality of spacers to space the head from the inner surface of the at least one tile the spacers being circumferentially spaced around the head of each stud, the head, the threaded portion and the spacers of each stud being integral. 
     
     
         4 . A combustion chamber as claimed in  claim 1  wherein the head of the at least one stud locates in a corresponding recess in the tile and the plurality of spacers space the head from the inner surface of the recess of the tile. 
     
     
         5 . A combustion chamber as claimed in  claim 4  wherein the surface of the head of the stud remote from the threaded portion is arranged flush with the inner surface of the tile. 
     
     
         6 . A combustion chamber as claimed in  claim 4  wherein an outer surface of the recess of the tile abuts an inner surface of the outer annular wall. 
     
     
         7 . A combustion chamber as claimed in  claim 1  wherein the spacers are cylindrical in cross-section or the spacers are rectangular in cross-section. 
     
     
         8 . A combustion chamber as claimed in  claim 7  wherein two of the sides of each rectangular cross-section spacers are arranged parallel to corresponding sides of the other rectangular cross-section spacers. 
     
     
         9 . A combustion chamber as claimed in  claim 1  wherein two of the sides of each spacer extend radially with respect to the stud to define a plurality of radially extending passages. 
     
     
         10 . A combustion chamber arrangement comprising an outer annular wall and an inner annular wall spaced from the outer annular wall, the inner annular wall comprising a plurality of tiles, at least one of the tiles being secured to the outer annular wall by at least one stud and a cooperating nut, the at least one stud comprising a head and a threaded portion extending from the head, the threaded portion of the at least one stud extending through an aperture in the at least one tile and an aperture in the outer annular wall, wherein the head comprising a plurality of spacers to space the head from an inner surface of the at least one tile, the spacers being circumferentially spaced around the head of the stud, the head, the threaded portion and the spacers of the at least one stud being integral, there are five spacers, a second spacer is angularly spaced apart from a first spacer by a first angle, a third spacer is angularly spaced apart from the second spacer by a second angle, a fourth spacer is angularly spaced apart from the third spacer by a third angle, a fifth spacer is angularly spaced apart from the fourth spacer by a fourth angle and the first spacer is angularly spaced apart from the fifth spacer by a fifth angle. 
     
     
         11 . A combustion chamber as claimed in  claim 10  wherein the first angle is greater than the second angle, the second angle is less than the third angle, the third angle is equal to the fourth angle, the fifth angle is less than the fourth angle and the first angle is greater than the fifth angle. 
     
     
         12 . A combustion chamber as claimed in  claim 10  wherein a middle of the fourth spacer and a middle of the first angle are arranged diametrically opposite each other. 
     
     
         13 . A combustion chamber as claimed in  claim 12  wherein the middle of the fourth spacer and the middle of the first angle are arranged parallel to the axis of the annular outer wall. 
     
     
         14 . A combustion chamber as claimed in  claim 12  wherein the middle of the first angle is arranged axially upstream of the middle of the fourth spacer. 
     
     
         15 . A combustion chamber as claimed in  claim 1  wherein the spacers are arcuate in cross-section and each spacer comprises a convex surface and a concave surface. 
     
     
         16 . A combustion chamber arrangement comprising an outer annular wall and an inner annular wall spaced from the outer annular wall, the inner annular wall comprising a plurality of tiles, at least one of the tiles being secured to the outer annular wall by at least one stud and a cooperating nut, the at least one stud comprising a head and a threaded portion extending from the head, the threaded portion of the at least one stud extending through an aperture in the at least one tile and an aperture in the outer annular wall, wherein the head comprising a plurality of spacers to space the head from an inner surface of the at least one tile, the spacers being circumferentially spaced around the head of the stud, the head, the threaded portion and the spacers of the at least one stud being integral, there are six spacers, the spacers are arcuate in cross-section and each spacer comprises a convex surface and a concave surface, wherein a second spacer is angularly spaced apart from a first spacer by a first angle, a third spacer is angularly spaced apart from the second spacer by a second angle, a fourth spacer is angularly spaced apart from the third spacer by a third angle, a fifth spacer is angularly spaced apart from the fourth spacer by a fourth angle, a sixth spacer is angularly spaced apart from the fifth spacer by a fifth angle and the first spacer is angularly spaced apart from the sixth spacer by a sixth angle. 
     
     
         17 . A combustion chamber as claimed in  claim 16  wherein the first angle is greater than the second angle, the second angle is less than the third angle, the third angle is less than the fourth angle, the fifth angle is less than the fourth angle, the sixth angle is less than the fifth angle and the first angle is greater than the sixth angle. 
     
     
         18 . A combustion chamber as claimed in  claim 16  wherein a middle of the first angle and a middle of the fourth angle are arranged diametrically opposite each other. 
     
     
         19 . A combustion chamber as claimed in  claim 18  wherein the middle of the first angle and the middle of the fourth angle are arranged parallel to the axis of the annular outer wall. 
     
     
         20 . A combustion chamber as claimed in  claim 18  wherein the middle of the first angle is arranged axially upstream of the middle of the fourth angle. 
     
     
         21 . A combustion chamber as claimed in  claim 16  wherein the concave surface of the first spacer faces the concave surface of the second spacer, the convex surface of the second spacer faces the concave surface of the third spacer, the convex surface of the third spacer faces the convex surface of the fourth spacer, the concave surface of the fourth spacer faces the concave surface of the fifth spacer, the convex surface of the fifth spacer faces the convex surface of the sixth spacer and the concave surface of the sixth spacer faces the convex surface of the first spacer. 
     
     
         22 . A combustion chamber as claimed in  claim 1  wherein there is an even number of spacers and two adjacent spacers at a first radial side of the head being arranged further circumferentially apart than two adjacent spacers at a second opposite radial side of the head 
     
     
         23 . A combustion chamber as claimed in  claim 1  wherein there is an odd number of spacers and the middle of a spacer at a first radial side of the head and the middle of an angle between two adjacent spacers at a second opposite radial side of the head being arranged diametrically opposite each other. 
     
     
         24 . A combustion chamber as claimed in  claim 1  wherein the spacers are equi-circumferentially spaced around the head of the stud. 
     
     
         25 . A combustion chamber as claimed in  claim 1  wherein the at least one tile is manufactured by a method selected from the group consisting of casting and additive layer manufacturing, the at least one tile comprises a superalloy selected from the group consisting of a nickel based superalloy, a cobalt based superalloy and an iron based superalloy. 
     
     
         26 . A combustion chamber as claimed in  claim 1  wherein the at least one stud is manufactured by additive layer manufacturing, the at least one stud comprises a superalloy selected from the group consisting of a nickel based superalloy, a cobalt based superalloy and an iron based superalloy. 
     
     
         27 . A combustion chamber as claimed in  claim 1  wherein the at least one stud comprises a different material to the at least one tile and the at least one stud comprises a material with higher temperature capability than the material of the tile.