Patent ID: 8893509

Claim:
A gas turbine engine comprising: a compressor for compressing air to generate compressed air; a combustor for combusting fuel with the compressed air to generate combustion gas; a turbine supported for rotation about an axis so that it is driven to rotate by the contact with the combustion gas; an exhaust diffuser having inner and outer tubes both arranged coaxially with the axis to define an annular exhaust channel therebetween and a central cavity within the inner tube; a first passage extending radially through the outer and inner tubes, the first passage having a radially inward end and a radially outward end, the inward end being fluidly connected to the central cavity; an air supply having an ejector positioned at the radially outward end of the first passage for drawing environmental air into the first passage and a path fluidly connecting the compressor to the ejector for delivering the compressed air through the first passage into the central cavity such that said ejector mixes the environmental air with the compressed air to generate a cooling air; and a first opening defined in the inner tube to fluidly connect between the exhaust channel and the central cavity, the first passage and the first opening being so positioned that the cooling air is delivered from the air supply through the first passage, the central cavity, and the first opening into the exhaust channel as the cooling air makes thermal contact with an object positioned in the central cavity to cool the object.