화학공학소재연구정보센터
International Journal of Heat and Mass Transfer, Vol.95, 288-295, 2016
Enhanced evaporation from an oscillating liquid in a capillary tube
Enhanced evaporation inside a capillary tube into which the liquid/gas meniscus oscillates is experimentally studied. It is found that the meniscus oscillation can markedly level-off the evaporation rate, while keeping an apparent diffusive behaviour. The apparent diffusive coefficient can reach a tenfold increase in the explored range of parameters. The dependence of the effect is studied by varying the capillary tube diameter, the frequency and the amplitude of the liquid oscillations. The parametric dependence of the apparent diffusive coefficient is well captured by the associated dimensionless Peclet number. A nice collapse of the experimental measurements consistent with a quadratic scaling with Peclet number is found. Such scaling is suggested by previous theoretical and experimental analysis associated with a Taylor dispersion transport mechanism. Nevertheless the prefactor of those theory is found to under-predict the observed effect by a factor three. This deviation from Taylor's dispersion driven transport predictions is discussed. (C) 2015 Elsevier Ltd. All rights reserved.