Patent ID: 9206905
Filing Date: 2015-12-08
Classification: F01D,F05D,F16J

Abstract:
1. A leaf seal for effecting a seal between two coaxial and relatively rotating components, the seal having an annular pack of stacked leaves, the pack being mountable to a first one of the components at root portions of the leaves and extending towards the other component such that end edges of the leaves are presented for air-riding interaction with the other component during relative rotation between the components and, in use, a pressure drop is maintained axially across the pack; wherein the pack comprises a first set of leaves arranged around the pack, each of which is configured to present an end edge at least part of which is in intimate relationship with the other component; and a second set of leaves circumferentially interspersed throughout the first set, the leaves of the first and second sets cooperating to define, around the pack, a plurality of circumferential spaces between the end edges of successive leaves of the first set, said spaces being configured to create a circumferential variation in pressure around the pack which contributes to the generation of hydrodynamic lift between the pack and the other component during relative rotation between the components, wherein each leaf of said second set defines a radial gap between at least a region of its end edge and the other component, said radial gaps defining a radial dimension of said circumferential spaces.