On Analysis of Fluidelastic Instability in Air-Water Mixture

Abstract

Cross-flow-induced vibrations are important phenomena in the power generation industry as they may severely damage the heat exchanger tubes due to violent oscillations and clashing. The fluidelastic instability was identified as the main driving force behind the vibrations and is highly dependent on the flow regime (single-phase versus two-phase flow). The vorticity formulation has been shown in the past to sufficiently describe the phenomena of cross-flow-induced vibrations in cylindrical arrays. This paper attempts to use the existing, well-established equations (see Bottoni and Sengpiel, 1992) and compares the results of a fluidelastic instability of an air-water mixture to available experimental data. The proposed problem is solved using finite differences by discretizing the computational domain and assuming the initial positions of the tubes.