Patent ID: 8075256

Claim:
A seal assembly that limits gas leakage from a hot gas path to one or more disc cavities in a gas turbine engine comprising a plurality of stages, each stage comprising a plurality of stationary components and a disc structure supporting a blade structure comprising a row of airfoils for rotation on a turbine rotor, the seal assembly comprising: a seal apparatus that limits gas leakage from the hot gas path to a disc cavity associated with an axially facing side of the blade structure, said seal apparatus comprising: an annular inner shroud associated with adjacent stationary components, said annular inner shroud comprising a radially inwardly facing side and a radially outwardly facing side; a wing member extending axially from said axially facing side of the blade structure toward said annular inner shroud, said wing member including a radially inner side and a radially outer side; a first wing flange extending radially outwardly from said radially outer side of said wing member toward said radially inwardly facing side of said annular inner shroud, said first wing flange being curved in a radial direction and having a concave first surface facing said axially facing side of the blade structure and a second surface opposed from its concave first surface that faces away from said axially facing side of the blade structure, wherein a radially outer edge of said first wing flange is located proximate to said radially inwardly facing side of said annular inner shroud such that a radial first gap having a dimension in the radial direction is formed between said first wing flange and said radially inwardly facing side of said annular inner shroud; an outer region defined radially inwardly from the hot gas path between said axially facing side of the blade structure, said annular inner shroud, said radially outer side of said wing member, and said concave first surface of said first wing flange; a central region adjacent said outer region and defined between said wing member and said radially inwardly facing side of said annular inner shroud, and located adjacent to said second surface of said first wing flange; and wherein said concave first surface of said first wing flange limits a passage of working gas in said outer region through said radial first gap into said central region by recirculating at least a portion of said working gas in said outer region away from said radial first gap and back toward the hot gas path.