We have unveiled the role of confinement in the evaporation dynamics of sessile droplets. We have shown that the evaporation characteristics for such a droplet can be represented by a unique normalized mathematical function of the initial conditions, irrespective of the confinement dimensions and physical data. We have also extended the above studies to include the effects of tiny concentrations of suspended particles that may alter the behavior of an evaporating droplet remarkably. In sharp contrast to the unconfined scenario, we have unravelled unique flow transitions and remarkable suppression of instabilities of a nano-particle laden droplet in a confined fluidic environment, beyond a critical channel length, resulting in intriguing morpho-dynamics. Further, through extensive set of experiments and theoretical formulations, we have been able to trace and universally merge the volume evolution history of the droplets along with evaporation lifetimes, irrespective of the extent of confinement. We have also brought out the internal flow transitions caused by spatio-temporal variation of evaporation flux due to confinement. These findings may be of profound importance in designing functionalized droplet evaporation devices for emerging engineering and biomedical applications.
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