Interstage seal arrangement for airfoil stages of turbine engine

Abstract

A gas turbine engine has outer and inner counterrotatable annular turbine rotors and pluralities of turbine blades disposed in alternating rows and mounted on and extending between the respective rotors. An interstage seal arrangement for the engine is composed of a sequence of alternating inner and outer seals. Each outer seal is disposed between an interior side of the outer rotor and outer ends of the blades in one plurality thereof being spaced radially inward at their outer ends from the outer rotor and being mounted at their inner ends to the exterior side of the inner rotor. Each inner seal is disposed between the exterior side of the inner rotor and inner ends of the blades in another plurality thereof being spaced radially outward at their inner ends from the inner rotor and being mounted at their outer ends to the interior side of the outer rotor. Each inner seal is composed of an annular honeycomb component attached to the blade inner ends and a plurality of annular seal elements or teeth mounted on the exterior side of the inner rotor and projecting radially outwardly therefrom for sealably interfacing with the honeycomb component concurrently as the outer and inner rotors counterrotate relative to one another.