SEAL DEVICE AND TURBO MACHINE

摘要

PROBLEM TO BE SOLVED: To provide a seal device capable of restricting unstable vibration of a rotating shaft of a turbo machine without reducing the number of seal fins, and provide the turbo machine including the seal device.SOLUTION: A turbo machine comprises: a rotating body 1 having a rotating shaft 3; a stator 2 inwardly holding the rotating body 1; and a seal device 20 arranged at a clearance flow passage formed between an outer peripheral surface of the rotating body 1 and an inner peripheral surface of the stator 2 to restrict a leakage flow B from the clearance flow passage. The seal device 20 has: a plurality of seal fins 24 arranged in at least one of the rotating body 1 and the stator 2 and arranged side by side in an axial direction of the rotating body; and at least one speed reducing restriction body 25 arranged at the rotating side to protrude toward a chamber 30 formed between the seal fins 24 so as to restrict reduction in speed of the rotating body in its rotating direction of the leakage flow B in the chamber 30.SELECTED DRAWING: Figure 2