Double wall combustor arrangement

Abstract

A double wall structure for a combustor of a gas turbine engine comprising an inner wall, an outer wall and a rail assembly, the inner wall formed by discrete tiles, wherein each tile is secured to the outer wall by the rail assembly.

I claim:  
     
         1 . A double wall structure for a combustor of a gas turbine engine comprising an inner wall, an outer wall and a rail assembly, the inner wall formed by discrete tiles, wherein each tile is secured to the outer wall by the rail assembly.  
     
     
         2 . A double wall structure for a combustor of a gas turbine engine as claimed in  claim 1  wherein the gas turbine engine comprises a main engine axis and the combustor is annular and generally coaxial with the main engine axis and the rail assembly is substantially annular and coaxial with respect to the main engine axis.  
     
     
         3 . A double wall structure for a combustor of a gas turbine engine as claimed in  claim 1  wherein the rail assembly comprises co-operating and generally L-shaped cross-section hook features, the inner wall and outer wall define a gap therebetween and the hook features extend generally into the gap, one hook feature attached to the tile and one attached to the outer wall so that, in use, the hook features co-operate to secure the tile to the outer wall.  
     
     
         4 . A double wall structure for a combustor of a gas turbine engine as claimed in  claim 1  wherein the inner wall and outer wall define a gap therebetween and the rail assembly comprises a generally T-shaped hook feature and generally L-shaped hook features, the T-shaped hook feature attached to the tile and co-operating with the L-shaped hook features attached to the outer wall, the hook features extend into the gap and co-operate to secure the tile to the outer wall.  
     
     
         5 . A double wall structure for a combustor of a gas turbine engine as claimed in  claim 3  wherein the generally L-shaped cross-section hook feature defines a loading gap, the loading gap provided to allow the tiles to be assembled to the outer wall of the combustor.  
     
     
         6 . A double wall structure for a combustor of a gas turbine engine as claimed in  claim 5  wherein the rail assembly comprises a locking key, the locking key so configured to, in operation, substantially fill the loading gap and thereby secure the tiles to the outer wall.  
     
     
         7 . A double wall structure for a combustor of a gas turbine engine as claimed in  claim 1  wherein the rail assembly comprises a locking plate.  
     
     
         8 . A double wall structure for a combustor of a gas turbine engine as claimed in  claim 1  wherein the tile comprises an edge and the rail assembly is located in close proximity to the edge of the tile to provide stiffening thereof.  
     
     
         9 . A double wall structure for a combustor of a gas turbine engine as claimed in  claim 1  wherein the tile comprises an edge and the edge of the tile is profiled.  
     
     
         10 . A double wall structure for a combustor of a gas turbine engine as claimed in  claim 9  wherein the profiled edge of the tile comprises an end wall.  
     
     
         11 . A double wall structure for a combustor of a gas turbine engine as claimed in  claim 9  wherein the profiled edge of the tile comprises a cooling passage.