Experimental investigation of pool boiling heat transfer and bubble dynamics for the downward facing heating

The majority of this paper is to experimentally investigate the characteristics of boiling heat transfer and bubble dynamics for the downward facing heating through thermocouple measurement and high-speed camera observation. The measured bubble dynamics include the bubble departure diameter/frequency, the nucleation site density, and the bubble sliding velocity. The corresponding data from the previous works are used to be compared with to demonstrate the reasonability of present measurements. In addition, the original and modified wall heat flux partitioning model with input of the measured bubble dynamics are used to predict the boiling curve on the downward heating surface. Based on the comparison, the predicted boiling curve from the modified boiling model is closer to the present measurement. The present measured boiling curve and bubble dynamics can provide the useful information for validating the new-developing boiling heat transfer models. This is one of main contributions of this paper. (c) 2022 Elsevier Ltd. All rights reserved.