The effects of dissolved salt on the Leidenfrost transition

In this study, Leidenfrost experiments were conducted for water, NaCl, and KCl aqueous solutions at atmospheric pressure. In our tests, a 1.1 g test liquid was gently deposited on a horizontal heated aluminum surface. The evaporation time at various surface temperatures was recorded and plotted as evaporation curves. To examine the relationship between bubble coalescence, dissolved salt and the Leidenfrost transition, test surfaces were fabricated with arrays of small holes serving as artificial nucleating sites. Cavity spacing is 1 mm or 2 mm. It is demonstrated that the dissolved salt increases the Leidenfrost temperature. Mechanisms associated the Leidenfrost transition, such as suppression of bubble coalescence, variation in properties and salt deposition during the initial liquid-solid contact, are explored and accessed. (c) 2006 Elsevier Ltd. All rights reserved.