SEAL STRUCTURE, TURBINE MACHINE EQUIPPED WITH SAME, AND POWER PLANT EQUIPPED WITH SAID TURBINE MACHINE

摘要

A seal structure capable of suppressing disturbance of a main flow of fluid due to leakage fluid is provided. A seal structure includes shrouds (3a) that are provided at tips of a plurality of blades (2) on which a main flow of fluid impinges and that come into contact with adjacent shrouds to form a cylindrical shape; a sealing part (5c) connected to a structure body (4) facing the shrouds (3a); and a space (7) that is defined by downstream sides of the shrouds (3a), a downstream side of the sealing part (5c), and a wall (4b) on a downstream side of the structure body (4), the space and that communicates with the main flow of fluid that has impinged on the blades (2). An end (4d) of the wall (4b) on the downstream side of the structure body (4) is formed so as to be disposed a predetermined distance away from a shroud extension (11) extending toward the downstream side of the shrouds (3a) and away from a sealing-part extension (10) provided substantially parallel to the shroud extension (11) and extending toward the downstream side of the sealing part (5c) and so as to be located on the opposite side of the shroud extension (11) with respect to the sealing-part extension (10).