Theoretische Physikalische Chemie, Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt , Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany.
Institute of Technical Thermodynamics, Technische Universität Darmstadt , Alarich-Weiss-Straße 10, 64287 Darmstadt, Germany.
Langmuir. 2017 May 30;33(21):5336-5343. doi: 10.1021/acs.langmuir.7b01410. Epub 2017 May 16.
We study the role of solid-liquid interface thermal resistance (Kapitza resistance) on the evaporation rate of droplets on a heated surface by using a multiscale combination of molecular dynamics (MD) simulations and analytical continuum theory. We parametrize the nonbonded interaction potential between perfluorohexane (CF) and a face-centered-cubic solid surface to reproduce the experimental wetting behavior of CF on black chromium through the solid-liquid work of adhesion (quantity directly related to the wetting angle). The thermal conductances between CF and (100) and (111) solid substrates are evaluated by a nonequilibrium molecular dynamics approach for a liquid pressure lower than 2 MPa. Finally, we examine the influence of the Kapitza resistance on evaporation of droplets in the vicinity of a three-phase contact line with continuum theory, where the thermal resistance of liquid layer is comparable with the Kapitza resistance. We determine the thermodynamic conditions under which the Kapitza resistance plays an important role in correctly predicting the evaporation heat flux.
我们通过分子动力学(MD)模拟和分析连续体理论的多尺度组合,研究固液界面热阻(卡皮查热阻)对加热表面上液滴蒸发速率的影响。我们参数化了全氟己烷(CF)和面心立方固 体表面之间的非键相互作用势能,以通过固液粘附功(与润湿角直接相关的量)再现 CF 在黑铬上的实验润湿行为。对于低于 2 MPa 的液体压力,我们通过非平衡分子动力学方法评估了 CF 与(100)和(111)固体衬底之间的热导率。最后,我们通过连续体理论研究了在三相接触线附近液滴蒸发时卡皮查热阻的影响,其中液体层的热阻与卡皮查热阻相当。我们确定了卡皮查热阻在正确预测蒸发热通量方面发挥重要作用的热力学条件。