Session: 23-11, Labyrinth Seals

Paper Number: 128188

128188 - Sensitivity Analysis of Simplified Labyrinth Seals Model Stability to Flow Hypotheses 

Labyrinth seals are a wide diffused non-contacting mechanical subsystem of space engines turbopumps. Thanks to a sequence of teeth and cavities, they provide to the working flow a tortuous path limiting leakage and recirculation phenomena through rotor/stator gap and they guarantee more efficient engine performances. The high fluctuations of pressure and velocity experienced by the flow running through labyrinth seals, together with the necessity for light structures, make them subject to aeroelastic instabilities. This problematic is object of in-depth investigations in order to prevent failures caused by fatigue and provide safer turbopumps. In this work, the analysis of a straight-through one-cavity labyrinth gas seal stability is conducted through the development of a Navier-Stokes one-dimensional fluid model monolithically coupled to an elastic structure model. To this end, a sensitivity study to the variation of different parameters is presented, with a particular focus on the role of the energy equation, the leakage flow formulation and, for a viscous flow, the shear stress model. This study will allow to identify the features which mainly influence the analysed system solution, under the hypothesis of strong fluid-structure coupling. The final aim is to characterize and examine the stable/unstable behaviour of labyrinth seals for different assumptions.

Presenting Author: Giorgia Foschi Ecole Centrale of Lyon

Presenting Author Biography: With a Master’s degree in Space and Astronautical engineering, Giorgia Foschi is a third-year PhD student at the Ecole Centrale of Lyon. She is currently pursuing an experimental thesis on the aeroelastic instability of labyrinth seals in space engines at the Laboratory of Tribology and Dynamics of Systems (LTDS), in collaboration with CNES and ArianeGroup.

Authors:

Giorgia Foschi Ecole Centrale of Lyon
Fabrice Thouverez Ecole Centrale of Lyon
Laurent Blanc Ecole Centrale of Lyon
Giuseppe Fiore Centre National d’Etudes Spatiales
Giampiero Pampolini Ariane Group SAS
Patrick Girard Safran Aircraft Engines