TURBINE AIRFOIL WITH AMBIENT COOLING SYSTEM

摘要

A turbine airfoil (12) usable in a turbine engine and having at least one ambient air cooling system (10) is disclosed. At least a portion of the cooling system (10) may include one or more cooling channels (16) configured to receive ambient air at about atmospheric pressure. The ambient air cooling system (10) may have a tip static pressure to ambient pressure ratio of at least 0.5, and in at least one embodiment, may include a tip static pressure to ambient pressure ratio of between about 0.5 and about 3.0. The cooling system (10) may also be configured such that an under root slot chamber (54) in the root (40) is large to minimize supply air velocity. One or more cooling channels (16) of the ambient air cooling system (10) may terminate at an outlet (20) at the tip (22) such that the outlet (20) is aligned with inner surfaces (24) forming the at least one cooling channel (16) in the airfoil (12) to facilitate high mass flow.