INNER PLATFORM IMPINGEMENT COOLING BY SUPPLY AIR FROM OUTSIDE

摘要

A stator blade assembly for a gas turbine engine having: an outer shroud with an air supply port ; an inner shroud including a blade platform and a plenum enclosure defining a plenum bounded by an inner surface of the blade platform; and a blade spanning between the outer and inner shrouds. The blade has a leading edge portion with a passage communicating between the plenum and the air supply port of the outer shroud and an internal blade cooling channel communicating between the passage and apertures adjacent the trailing edge of the blade. The plenum includes an impingement plate wich includes impingement cooling apertures to direct cooling jets of air at the inner blade platform. An air flow restriction plate covers the inner end of the passage and controls the pressure and quantity of air delivered to the plenum via a compressed air metering aperture.