Numerical Investigation of Geometric Parameters on Labyrinth Seal Performance in a Centrifugal Compressor

Labyrinth seals play a crucial role in turbomachinery performance by minimizing leakage flow between high and low-pressure regions. This study investigates the effects of geometric parameters on the performance of a labyrinth seal using computational fluid dynamics (CFD) simulations. The analysis focuses on three design parameters: tooth number (single, double, and four-tooth), clearance (۰.۱, ۰.۲, and ۰.۴ mm), and tooth geometry (conical and rectangular). The numerical results demonstrated that increasing the number of teeth from one to four reduces the leakage mass flow rate by ۳۶.۲% respect to single-tooth configuration. Tooth geometry comparison revealed that rectangular profiles achieve marginally better sealing performance than conical designs, showing a ۹.۸% reduction in leakage flow respect to similar conical configuration. The clearance also influences the seal's performance, where increasing the gap from ۰.۱ mm to ۰.۴ mm results in an increase in leakage mass flow rate from ۱.۵۲% to ۸.۱۵%. The pressure drop trend shows a more even distribution across multiple teeth, with average drops of ۷% and ۵.۵% per tooth for conical and rectangular geometries, respectively, along with a slight improvement in system efficiency in multi-tooth arrangements. This study concludes that optimal sealing performance is achieved by combining multiple teeth, minimal clearance, and careful selection of tooth geometry.

Keywords:

Labyrinth seal , Computational fluid dynamics , Sealing performance