Wall elements for gas turbine engine components

Abstract

A wall structure for a gas turbine engine combustor has an inner wall and an outer wall defining a duct, the wall structure including an outer wall having a radial step and an inner wall overlapping the radial step, a duct being defined between the inner and outer walls for the passage of cooling air; the wall structure being characterised in that the inner wall has a local thickening opposing the radial step. The velocity of cooling air through the duct is maintained and heat transfer subsequently improved.

1 . A wall structure for an annular gas turbine engine combustor arranged to have a general direction of fluid flow therethrough, the wall structure including an outer wall having a radial step and an inner wall overlapping the radial step, a duct being defined between the inner and outer walls for the passage of cooling air; the wall structure being characterised in that the inner wall has a local thickening opposing the radial step and a plurality of pedestals extending from the local thickening towards the outer wall. 
   
   
       2 . A wall structure according to  claim 1 , wherein the outer wall has a plurality of apertures for feeding cooling air into the duct. 
   
   
       3 . A wall structure according to  claim 1 , wherein the inner wall includes a plurality of wall elements, each wall element having a body portion aligned in use with the general direction of fluid flow through the combustor and a plurality of pedestals that extend within the duct from the body portion towards the outer wall. 
   
   
       4 . A wall structure according to  claim 3 , wherein the body portion provides the local thickening. 
   
   
       5 . A wall structure according to  claim 3 , wherein the downstream end of the body portion of an upstream wall element overlaps the upstream end of the body portion of a downstream wall element. 
   
   
       6 . A wall structure according to  claim 1 , wherein the local thickening has a contour that follows the contour of the radial step. 
   
   
       7 . A wall element for use as part of an inner wall of a gas turbine engine combustor wall structure including inner and outer walls, the inner and outer walls defining a duct therebetween, the wall element having a body portion aligned in use with a general direction of fluid flow through the combustor, the wall element having a local thickening in its downstream end region the local thickening being adapted to oppose a radial step in the outer wall and having a plurality of pedestals arranged in use to extend within the duct from the body portion towards the outer wall.