Patent ID: 8807942

Claim:
A cooling arrangement for a turbine disc of a gas turbine engine, the turbine disc having a plurality of circumferentially spaced disc posts forming fixtures therebetween for a row of turbine blades, each turbine blade having an attachment formation which engages at a respective fixture, a platform radially outwardly of the attachment formation such that the adjacent platforms of the row form an inner endwall for a working gas annulus of the engine, and an aerofoil which extends radially outwardly from the platform, wherein a respective cavity is formed between an exposed radially outer surface of each disc post and the inner endwall; wherein the cooling arrangement comprises: at each disc post, a cooling plate having one or more exit holes formed therein for transferring spent coolant from a cooling channel to the cavity, each cooling plate being removably locatable in the respective cavity and spaced radially outwardly from the exposed outer surface of the disc post and spaced radially inwardly from the platform so that the entirety of the cooling plate does not touch the platform and forms the cooling channel between the cooling plate and the exposed outer surface, each cooling plate covering substantially the entire exposed outer surface, and a coolant supply system for supplying coolant to the cooling channels, wherein the coolant supply system diverts a portion of a flow of coolant for internally cooling the aerofoils towards the cooling channels, the system comprising a plurality of passages extending across the front and/or the rear faces of the disc post from a base of the fixtures for the turbine blades to the forward and/or rearward ends of the cooling channels respectively.