Mainstream Ingress Suppression in Gas Turbine Disk Cavities

Abstract

The sealing characteristics of an air-cooled gas turbine disk cavity have been studied using laser sheet flow visualization. Experiments were performed on a simplified half-scale model of an actual gas turbine disk cavity. This type of rotor–stator geometry with a double-toothed-rim (DTR) seal at the outer periphery and a labyrinth seal at the inner periphery of the cavity has been tested for its ability in preventing ingress of hot mainstream gases. The results show good agreement with previously esimated design data. Experiments were conducted for various labyrinth seal flow rates and rotational Reynolds numbers up to 1.52 × 106 . The effects of rotor eccentricity on minimum purge flows have also been discussed.