Nellevaporation

Nellevaporation is a term used in some academic discussions to describe a confinement-enhanced evaporation mechanism in which a liquid transitions to vapor more readily when confined within nanoscale or microscale porous structures. It is not a standard term in mainstream thermodynamics and is often described as speculative or exploratory in certain studies of phase change at interfaces.

The proposed mechanism relies on interfacial and geometric effects in confined spaces. Confinement increases the liquid–vapor interface area relative to volume, potentially shifting capillary pressures and reducing the energy barrier for molecules to escape as vapor. Local heating, thermal gradients, or applied electric fields can further promote evaporation within pores or channels, even when the bulk liquid temperature is below its usual boiling point.

Experimental implementations commonly use nanoporous materials, microfluidic networks, or porous membranes with pore sizes from tens to hundreds of nanometers. Key controls include pore size distribution, surface chemistry, ambient pressure, and temperature. Researchers emphasize careful accounting of menisci, contact-line pinning, and measurement artifacts that can mimic enhanced evaporation.

Applications suggested for nellevaporation include low-energy distillation in compact devices, dehydration of solvents in microreactors, and water treatment processes. At present, the concept remains debated, and results are preliminary. Some reports attribute observed effects to conventional locally heated evaporation or to uncertainties in pore-scale measurements.

Related topics include evaporation, capillarity, porous media, and microfluidics.