Influence of the substrate thermal properties on sessile droplet evaporation: Effect of transient heat transport

The lifetimes of evaporating sessile droplets are significantly extended by strong thermal effects

“…However, all of these works use the basic diffusion-limited model for droplet evaporation (see, for example, Popov 2005) which does not account for the variation of the saturation concentration of the vapour with temperature. As a result, none of these works accounts for the influence of the thermal properties of the system on the evaporation of the droplets, which can be significant (see, for example, Dunn et al 2008, 2009a,b, Sefiane & Bennacer 2011, Sobac & Brutin 2012, Ait Saada, Chikh and Tadrist 2013, Lopes et al 2013and Diddens et al 2017. The aim of the present work is to gain further insight into this issue by using an extended model to obtain asymptotic solutions for the evolution, and hence explicit expressions for the lifetimes, of droplets when the influence of the thermal properties of the system is strong.…”

Experimental study of water evaporation of sessile droplets on a solid substrate with different thermal conductivities

“…Sefiane et al [7,8] showed the strong influence of the substrate conductivity on evaporation of sessile drops. In recent work Lopes et al [9] used glass and silicon substrates with different conductivity and thermal diffusivity. They found that the thermal properties of the substrate have a strong influence on evaporation lifetime of a sessile droplet.…”

Solid Substrate Properties

“…David et al (2007) and Dunn et al (2009) coated different substrates with an aluminum layer, providing an initial contact angle of 60 for water droplets. In the work of Lopes et al (2013), the substrate's wettability was controlled with a grafted layer of polystyrene. Still et al (2014) sputtered a chromium layer of a submicron thickness over the substrates, which resulted in an initial contact angle of 73 for water on a SrF 2 substrate and 76 for water on a sapphire substrate immediately after deposition.…”

“…For a droplet radius of 1 mm, the diffusion time has the order of 0.05 s. This is much lower than the droplet evaporation time, which is typically several hundreds of seconds for droplets of different fluids, including water (David et al, 2007;Girard et al, 2008;Sobac and Brutin, 2012;Lopes et al, 2013), octane (Cazabat and Guéna, 2010), and blood . For the diffusion of water vapor in air at room temperature, D 5 2.1 3 10 25 m 2 /s (VDI-GVC, 2010).…”

“…Several numerical works have been devoted to the modeling of heat and mass transfer during the droplet evaporation on a finite-size substrate with the aim of predicting the droplet evaporation rate as a function of substrate properties (Dunn et al, 2008Sefiane et al, 2009;Semenov et al, 2010Semenov et al, , 2011Sefiane and Bennacer, 2011;Lopes et al, 2013;Saada et al, 2013). In all of these works, the droplet has been assumed to have a spherical shape.…”