Abstract: A seal assembly for restricting fluid leakage flow through a fluid leakage cavity defined between a first component and second component that is rotatable about an axis relative to the first component, the seal assembly having a fluid jet outlet configured to admit a fluid jet into the fluid leakage cavity in an upstream direction which is inclined to the axis, a first flow restriction located downstream of the fluid jet outlet and at a location such that the fluid jet admitted from the fluid jet outlet would impinge on the first flow restriction once the fluid jet has turned to flow in an axial direction, and a second flow restriction located downstream of the first flow restriction. An axial flow turbine having a turbine rotor mounted within a housing may incorporate such a seal assembly in a fluid leakage cavity defined between the turbine rotor and the housing.

Abstract: A seal assembly for restricting fluid leakage flow through a fluid leakage cavity defined between a first component and second component that is rotatable about an axis relative to the first component, the seal assembly comprising a fluid jet outlet configured to admit a fluid jet into the fluid leakage cavity in an upstream direction which is inclined to the axis, a first flow restriction located downstream of the fluid jet outlet and at a location such that the fluid jet admitted from the fluid jet outlet would impinge on the first flow restriction once the fluid jet has turned to flow in an axial direction, and a second flow restriction located downstream of the first flow restriction. An axial flow turbine comprising a turbine rotor mounted within a housing may incorporate such a seal assembly in a fluid leakage cavity defined between the turbine rotor and the housing.