CFD Simulation of Single Step and Double Notched Tooth for Labyrinth Seals

A variant “Stepped Double Notched Tooth” for conventional sharp teeth of a labyrinth seal has been proposed and investigated by three-dimensional CFD numerical modeling of the flow field. The purpose is to reduce total leakage through the seal. The tooth is numerically tested with both solid and honeycomb lands. CFD assumptions and analysis were validated by comparison with leakage data from stationary labyrinth seal experiments conducted by Stocker [1]. The baseline model considered for comparison study consists of the conventional straight-through four sharp knife shaped teeth in combination with solid and honeycomb land. The variant tooth is also straight having a sharp tip but has a stepped inclined notch opposing the flow at both sides of the tip. CFD analyses revealed that this double notched tooth reduces seal leakage by ∼10.7% when used with solid land and ∼12.5% when used with honeycomb land compared to a conventional baseline tooth.