Heat transfer in nucleate boiling outside horizontal tube bundles, part 2. Prediction for tube bundle effect

This study presents a method of predicting the tube bundle effect and thus the enhanced heat-transfer coefficient based on a simile model proposed by Mikic and Rohsenow for pool boiling. The present model is composed of two heat-transfer mechanisms: (1) convection due to the generating bubbles on a tube of interest, and (b) convection due to the rising bubbles from tubes below. The latter mechanism accounts for the enhanced boiling heat transfer within a tube bundle. The model satisfactorily predicts the measured heat-transfer coefficients for various bundles of different numbers of tubes in a vertical row and for either equal or unequal heat fluxes supplied to tubes under various system pressures.