Experimental evidence of the atmospheric convective transport contribution to sessile droplet evaporation

We investigate the contribution of the natural convective transport in the vapor phase on the evaporation rate of an evaporating sessile droplet. When comparing the experimental data with the quasi-steady diffusion-controlled evaporation model, an increasing deviation with substrate temperature that was attributed to the effect of the natural convection on the vapor field has been recently highlighted. To validate this analysis, we present experimental results obtained with two gravity levels: 1 g and mu. The contribution of the natural convection is analyzed with the Grashof number, and an empirical model is developed combining diffusive and convective transport. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4792058]