Spreading and evaporation of sessile droplets: Universal behaviour in the case of complete wetting

Experiments on spreading and evaporation of sessile droplets on a solid substrate under various conditions are reported and compared to the developed theoretical model. The liquids used were alkanes: heptane and octane. All liquids completely wet glass substrates used. The time evolution of the radius of the droplet base, contact angle and the droplet height were monitored. The developed theoretical model predicts that measured radius and contact angle data, and the subsequently calculated volume data, would fall onto respective theoretical ‘universal curves’. Experimental data both extracted from literature and our own confirmed this theoretical prediction. The predicted universal curves fairly fit experimental data both extracted from literature sources and our own.