Evaporation of Micro-Droplets: the Radius-Square-Law Revisited
نویسندگان
چکیده
The range of applicability of a fundamental tool for studying the evolution of droplets, the radius-square-law , was investigated both analytically and numerically, on the basis of the experimental results of our own as well as of other authors. Standard issues were brie y discussed. Departures from the radius-square-law caused by the in uence of impurities encountered in non-ideal liquids, by the kinetic and surface tension e ects encountered for small droplets or by thermal imbalance encountered in light-absorbing droplets were analysed. The entanglement between the kinetic and impurities e ects was studied numerically yielding a possible explanation to evaporation coe cient discrepancies found in the literature. An unexpected radius-square-law persistence in case of non-isothermal evolutions of very small droplets in atmosphere nearly saturated with vapour was analysed. The coexistence of the kinetic e ects and the strong e ects of surface tension was found responsible for this e ect.
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