Predicting Oscillatory Fluid-Elastic Instability of a Tongue-in-Groove Leakage Joint

Abstract

This paper describes the application of the small boundary displacement model (SBDM) of fluid-structure coupling for predicting oscillatory fluid-elastic instability of a tongue-in-groove leakage joint. This coupling model extends structural small displacement theory to fluid-structure interfaces, eliminating the need for temporally changing meshes when structural motion is small compared with joint dimensions. The SBDM algorithm accurately predicts the onset of oscillatory instability for a tongue-in-groove leakage joint when compared with experimental data. Even though the methodology is specifically applied to a tongue-in-groove joint, the approach is equally suitable for evaluating the fluid-elastic stability of leakage joints in general.