EVAPORATION OF SINGLE LIQUID DROPS IN AN IMMISCIBLE LIQUID: EXPERIMENTS WITHnPENTANE DROPS IN WATER AND PREPARATION OF NEW HEAT TRANSFER CORRELATIONS

摘要

Experiments have been performed with n-pentane drops 2.0−6.5 mm in diameter evaporating in water under pressures of 0.11−0.49 MPa. The results obtained here complement those obtained by Shimizu and Mori [1] with smaller drops (1.4−1.7 mm in diameter). It is pointed out that the instantaneous heat transfer coefficient for each drop, evaporating and thereby taking the form of a liquid/vapor two-phase bubble, can be defined in four different ways, depending on how one takes account possible evaporation of the surrounding water into the bubble. Heat transfer correlations relevant to different definitions of the heat transfer coefficient are presented simultaneously, along with a correlation for the instantaneous rise velocity of bubbles.