Some problems on the estimation of flow-induced vibration of a tube array subjected to two-phase flow

There are some published papers on the estimation of the instability of a long span tube array subjected to liquid-vapour two-phase flow. They are, however, usually based on the Connor's type stability criteria for a single-phase flow. One of the authors published unique criteria for two-phase flow based on a separate flow model for liquid flow and for gas flow two years ago. In this paper it is shown that this new method gives quite reasonable results for recently measured expensive test results for a U-bend tube array in a Freon two-phase flow condition, although the method is based only on published data for single-phase flow. Throughout the comparison fundamental insight into the two-phase now induced instability is attained.