Computational analysis for scallop seals with sickle grooves, part II: Rotordynamic characteristics

Abstract

This paper represents the results of calculation of rotordynamics and leakage rate characteristics of scallop seals with sickle grooves (SSSG) depending on seal geometry. The Computational Fluid Dynamics (CFD) technique is used for calculation of hydrodynamic and rotordynamics characteristics of seal with one shaft axis radial excitation. The rotordynamics coefficients were obtained by using Instationary Perturbation Method (IPM). The comparison of the calculated scallop seal characteristics with those of the smooth, labyrinth, and damper seals has been performed. The flow physics and the friction losses mechanism, in terms of wall tangential friction factors, and their influence on the dynamic characteristics and the leakage rate in the scallop seal have been investigated. In addition, the seal geometry influence on the friction losses and the pressure drop values along the seal length have been studied. This study confirmed the fairly high dynamic characteristics of the scallop seals and also their frequency dependencies. (C) 2020 Elsevier Ltd. All rights reserved.