Patent ID: 6565312
Filing Date: 2003-05-20
Classification: F01D

Abstract:
A cooled blade for a turbine, comprising:a blade structural member extending along a blade longitudinal axis from an inner end to an outer end of the structural member and having a generally airfoil-shaped cross-section normal to the longitudinal axis; a heat-transfer sheath surrounding and bonded to an outer surface of the structural member, the heat-transfer sheath defining an external aerodynamic surface of the blade; and coolant passages defined between the heat-transfer sheath and the structural member, whereby coolant passed through the coolant passages extracts heat from the heat-transfer sheath to cool the blade, each coolant passage forming a closed cooling circuit separate from the other coolant passages, each coolant passage entering one end of the blade and extending toward the opposite end of the blade and then back out the one end of the blade such that all coolant in each coolant passage is recovered, whereby the blade is cooled without dumping coolant into a main gas flow path of the turbine.