Principal Investigator: Chao Chen, Quanshui Zheng
Evaporation of liquids at the nanoscale is of great importance for biological activities as well as nanofluidic systems. At the nanoscale, due to disjoining forces, liquid films can be under high negative pressures which can lead to, for example, the ascent of sap in tall trees , liquid boiling at temperatures much lower than saturation temperatures , ultra high heat fluxes , and so on. The first experiment on the evaporation of water from Al2O3 nanopores with average size of 50 nm has shown that the tested nanoscale confinement can increase the water evaporation rate by at least an order as compared with the evaporation rate at normal surface . This experimental discovery may serve as the fundamental basis for the development of novel device for low-energy but high-speed room temperature evaporation of seawater.
Due to the complexities and difficulties involved in the nanoscale evaporation experiments, molecular dynamics remains a vital tool to characterize the evaporation behaviour of liquids at the nanoscale. In this project large scale non-equilibrium molecular dynamics simulations will be carried out to investigate the effect of confinement size, temperature, contact angle, and vapor pressure on the liquid evaporation under nanoscale confinement. The proposed project aims to provide deeper insight on the molecular mechanism of liquid evaporation under nano-confinement, which will in turn guide future development of novel cooling technologies and water purification devices.
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