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

Visualization study of evaporation of single n-pentane drops in water

“…Recent experimental studies on heat transfer to evaporating two-phase bubbles in our laboratory (Shimaoka and Mori, 1990) indicate a lowering of the heat transfer coeffi- cient with an increase of AT*.1 Shimaoka and Marl (1990) assume that this fact can be ascribed to an increasing loss, with increasing AT*, of some secondary fluid motions around and/or inside bubbles, such as vortex sheddings, that may cause shape oscillations of the bubbles and thereby promote sloshing of the yet-to-be-vaporized liquid inside the bubbles. As stated before, the present observations clearly show a trend toward reduction of rocking motions of bubbles and accompanying wakes with an increase in A T*.…”

“…This enabled accurate collation of shadowgrams with the dilatometer record obtained in the same experimental run. For the processing of the photographically and dilatometrically obtained data, consult some of the prior reports from our laboratory (Shimizu and Mori, 1988 a,b;Shimaoka and Mori, 1990).…”

An analytic model of direct‐contact heat transfer in spray‐column evaporators

“…The values of T* and T, in the n-pentanelwater and cyclopentane/ water systems are listed in Table 1. Shimizu and Mori (1988) and Shimaoka and Mori (1990) …”

“…holes at a velocity of 0.65-0.70 m/s and disintegrated into drops of approximately 1.4 mm dia. Tables (1989) and Mori, 1990), as long as a and hence C are evaluated on the basis of the above definition of AT, the characteristics of heat transfer to individual two-phase bubbles never contribute, by themselves, to the positive dependency of a, on AT. We need to find some other factors that possibly induce an excessive increase in a, with an increase in AT, or alternatively a reduction in a, with the decrease in AT.…”

“…Several different initial drop diameters are assumed arbitrarily in each set of predictions, considering the uncertainty of the drop size in the corresponding experiments. According to Shimizu and Mori (1988), C is set at 0.169, although that may be a slight underestimation for drops larger than 2 mm in initial diameter (Shimaoka and Mori, 1990).…”