Patent ID: 7300251

Claim:
A cooled blade of a gas turbine engine, comprising: a blade wall having an inner wall surface and an external wall surface; a cooling passageway formed by said inner wall surface inside said blade wall of said cooled blade for the flow of cooling air therein; film-cooling holes formed so as to penetrate through said blade wall from said inner wall surface and said cooling passageway to said external wall surface and so as to form a cooling film on said external wall surface of said blade wall; an impingement cooling member arranged in said cooling passageway so as to be spaced with a predetermined gap from said inner wall surface of said blade wall, said impingement cooling member comprising a multiple number of small holes for ejecting cooling air; and a sealing portion mounted in said gap between said impingement cooling member and said inner wall surface so as to divide said gap in a blade chord direction and so as to separate adjacent said film-cooling holes in the blade chord direction; wherein said film cooling holes are holes that have a cylindrical and straight portion extending from said inner wall surface to the proximity of said external wall surface and further have a shaped portion spreading in a direction along said external wall surface in the proximity of said external wall surface, said shaped portion comprising a laid-back portion dug in a direction intersecting said external wall surface; and wherein a multiple number of fin-shaped protrusions are provided on said inner wall surface in said gap and arranged in a line perpendicular to, or at a predetermined angle relative to, said sealing portion, each of said fin-shaped protrusions being divided so as to be arranged symmetrically about said film-cooling holes.