Session: 22-05 Flutter models

Paper Number: 102600

102600 - Experimental Validation of a Seal Flutter Model 

The predictions of an analytical model for seal flutter have been compared with the experimental data of a rotating multi-cavity labyrinth seal test rig. The experiments were conducted to assess the flutter inception in a large set of operating conditions by varying the rotational speed and the total pressure ratio across the seal. The sensitivity of the stability to the clearance variation is also studied for straight-through and stepped configurations. The analytical model derived by Corral et al. (2022, “ Effective Clearance and Differential Gapping Impact on Seal Flutter Modelling and Validation,” ASME J. Turbomach, 144 (7), pp. 071010) has been previously validated by using a frequency domain linearized Navier-Stokes solver retaining the effect of the effective gaps and the kinetic energy carried over to downstream fin. To reduce the uncertainty, a set of 3D steady RANS simulations is performed and the steady characteristics of the seal are used to inform the flutter model. The effect of dissimilar gaps has been studied by generating a set of numerical models with geometrical gap differences. The stability limit has been investigated in a large range of operating conditions. Firstly, the nondimensional parameters controlling seal flutter will be introduced, then the test rig, the test matrix, and the numerical setup of the simulations, are described. Finally, the experimental data are compared with the prediction of the analytical model in a wide range of operating conditions.

Presenting Author: Michele Greco Universidad Politécnica De Madrid

Presenting Author Biography: Michele obtained his Master Degree in Mechanical Engineering at the University of Florence. He is currently a PhD candidate at the Universidad Politécnica de Madrid. His research focuses on aeroelasticity in turbomachinery

Authors:

Roque Corral Universidad Politécnica de Madrid
Michele Greco Universidad Politécnica De Madrid