Molecular dynamic study of friction factor of water flowing through nanochannels with different wall hydrophobicity
Paper ID : 1059-ICNS
Authors:
Alireza Shadloo-jahromi *, Masoud Kharati-Koopaee, Omid Bavi
Department of Mechanical and Aerospace Engineering, Shiraz University of Technology, Shiraz, Iran
Abstract:
In this paper, we employed non-equilibrium molecular dynamics simulation to investigate the friction factor and slip length for water flow confined between silicon surfaces in nanochannels at different Reynolds numbers. Two silicon surfaces were used to construct the wall of nanochannels. The interaction strength, ε_(si-W), between the wall atoms and water’s oxygen atoms was adjusted for the five cases to represent different wall interfacial properties. To calculate the friction factor, the shear viscosity has also been calculated for each case. It is found that the shear viscosity of confined water grows by increasing the ε_(si-W). Flow of water molecules at different Reynolds numbers was attained by applying various external forces to each water molecules. Simulation results indicate that for the five studied cases, more hydrophilic walls lead to higher Darcy-Weisbach friction factor and lower slip length for the flow and also by increasing the Reynolds number the friction factor decreases.
Keywords:
Friction factor, Viscosity, wall hydrophobicity, Slip length, Nanoconfined water, Molecular Dynamic dynamic simulation
Status : Abstract Accepted (Oral Presentation)