The degradation of abradable honeycomb labyrinth seal performance due to wear

This feature presents work undertaken to improve the understanding of the behaviour and performance of worn abradable honeycomb labyrinth seals. An experimental programme, backed up by CFD analysis, has investigated a range of clearances and pressure ratios plus the effect of tooth to groove location against a baseline using a flat metal stator. Significant increases in mass flow have been recorded when using a worn honeycomb stator. However, these increases can be reduced by running with the labyrinth teeth displaced with respect to the groove.