Numerical Investigation of Worn Labyrinth Seals

The objective of this study was to develop a Computational Fluid Dynamics (CFD) based methodology to obtain the flow characteristics of worn and unworn labyrinth seals which will be applicable over a wide range of seal geometries. In this paper, we present a process to analyze worn and unworn seals with honeycomb lands using the CFX suite of software. Honeycomb structure poses an additional challenge due to disparate length scales. This was addressed by using separate meshes for the honeycomb and the seal tooth and by connecting them with a generalized grid interface in CFX. The challenges involved in modeling worn seals and an approach for quality meshing of the same was discussed. Comparisons were made with the test data from seals with unworn honeycomb lands. The leakages for the worn seals were also analyzed.