On modeling fluidelastic instability in tube arrays subjected to two-phase cross-flow

摘要

An experimental program was undertaken in order to improve our understanding of the mechanism of fluidelastic instability in two-phase flows and to provide practical design guidance to avoid vibration problems in heat exchangers. Different ways of defining the traditional parameters, such as void fraction, damping, velocity, and 2 phase fluid density, were examined. It was found that the damping in quiescent fluid combined with the gamma densitometer measured void fraction and the interfacial velocity, collapses the available data well and provides the expected trend of two-phase flow stability data over the void fraction range from liquid to gas flows. The resulting stability maps represent a significant improvement over existing maps for predicting fluidelastic instability of tube bundles in two-phase flows. This result also tends to confirm the hypothesis that the basic mechanism of fluidelastic instability is the same for single and two-phase flows, providing that the parameters are properly defined. (C) 2019 Elsevier Ltd. All rights reserved.