Patent attributes
A stepped labyrinth seal having a plurality of teeth forming gaps between a stationary honeycomb member, where the cavities formed between adjacent teeth include a plurality of vortex flow generating strips on the wall of the cavity that redirect the leakage flow from a gap back toward the gap and in a direction toward the gap in order to limit the leakage flow through the gap. The vortex generating strips extend along the cavity floor and up the sides of the teeth forming the cavity. The strips slope downward from the downstream tooth toward the upstream tooth in the direction of rotation, and with a curvature in the direction of rotation. The stepped labyrinth seal is intended for use in a gas turbine engine having a plurality of stages in the turbine, with the labyrinth seal being used to seal the gap between rotating blades and the honeycomb surface on the stationary casing.