Variation of Bubble Departure Frequency by Interaction between Nucleation Sites in Subcooled Flow Boiling

Abstract

Many correlations have been developed so far for the bubble departure frequency in forced convective subcooled boiling, but their prediction capability is still not satisfactory and further improvement is required. In this study, bubble behavior and wall temperature transient were visually observed using a high-speed camera and an infrared camera, respectively, to measure the bubble departure frequency and bubble diameter at each active nucleation site individually. It was found that nucleation is interfered by the wall temperature reduction caused by the bubble formation at nearby nucleation site. This indicates that the effect of interference from nearby nucleation sites should be included for accurate prediction of the bubble departure frequency.