STATE-OF-THE-ART REVIEW ON FLOW PATTERNS, SUPERFICIAL VOID FRACTION AND FLOW-INDUCED VIBRATION DURING TWO-PHASE FLOWS ACROSS TUBE BUNDLES

摘要

This paper presents a comprehensive review on the open literature concerning two-phase flow across horizontal tube bundles. Initially, experimental studies available in the literature are described in an organized manner. This detailed description includes bundle configurations and the experimental techniques used for evaluating flow patterns, void fraction and flow-induced vibration. Most of studies were performed having air-water as working fluids. Several excitation mechanisms can be reproduced such as flow periodicity, fluid-elasticity and turbulence. Flow patterns are discussed and their predictive methods are compared. Void fraction predictive methods are also discussed and comparisons among them are presented. It was found that the predictive methods worked reasonably well when compared against the databases used during their development. Generally, the studies have obtained bundle average measurements which are not representative of the local conditions and, therefore, are not recommendable to be used as accurate designing tools. Most studies concerning fluid-induced vibration have addressed this problem through simplified bench structures, usually consisting of a single rigid tube over a flexible suspension.