International Journal of Heat and Mass Transfer, Vol.139, 77-86, 2019
Single droplet with or without additives impacting on high-temperature burning liquid pool
This paper is a follow-up study for the phenomenon of vapor explosion for single water droplet impacting on a hot liquid pool. To explore the effects of vapor explosion on the dynamics of single droplet interacting with burning liquid pool, a series of experiments of pure water, water droplet with 5% NaCl, water droplet with 3% AFFF, and HFE-7100 droplet impacting on high-temperature burning oil were performed. For the cases of pure water, water droplet with 5% NaCl, and water droplet with 3% AFFF, vapor explosion can occur when the oil temperature reaches 210 degrees C. For the case of HFE-7100 droplet, however, the vapor explosion can only appear when the oil temperature ranges from 180 to 190 degrees C. Moreover, the vapor explosion has a significant effect on flame expansion. The flame expansion intensity is quantified by calculating the flame area and volume. Flame expansion intensity can rank as pure water droplet > droplet with 5% NaCl > droplet with 3% AFFF. (C) 2019 Elsevier Ltd. All rights reserved.