Heat Transfer in Nucleate Boiling outside Horizontal Tube Bundles : 2nd Report, Prediction for Tube Bundle Effect

Abstract

Heat transfer in nucleate boiling from a tube in a horizontal bundle deviates from that on a single tube in a pool. This difference refers to the tube bundle effect for brevity, which implies enhancement or deterioration in heat transfer. This paper presents a predictive method for enhanced heat transfer by adopting a model similar to that proposed by Mikic and Rohsenow for pool boiling, in which heat is transferred by two convective components, one due to generating bubbles and another due to flowing bubbles, and the latter contribution accounts for the enhancement of heat transfer in a tube bundle. The prediction for various bundles of different numbers of tubes in a vertical row and for different distributions of heat flux reproduces well the experimental data in the whole range of heat flux supplied to the tube concerned under various pressures.