Fluid seal

摘要

An annular seal (30) is provided between a turbine rotor disc (24) and the adjacent static structure (20). The seal comprises rotor fins (32) extending from the turbine disc (24) for rotation therewith and an abradable honeycomb layer (36) radially outward of the rotor fins (32). The abradable honeycomb layer (36) is located on the inner diameter of a sealing ring (34) attached to the static structure (20). The sealing ring (34) is moveable in an axial direction so that in operation the honeycomb (36) has one axial position for transient conditions and an alternative axial position for stabilised running. The seal clearance can thus be optimised at the two axial positions reducing the leakage flow through the seal (30). <IMAGE>