Determination of the Mass Diffusion Coefficient of H2o Diluted in N2 Using Classical Molecular Dynamic Simulation

Abstract

In this work, the auto-correlation function of the center of mass velocity has been used to deduce the mass diffusion coefficient (D) of water diluted in nitrogen using the Classical Molecular Dynamics Simulations (CMDS). The calculations have been performed at room temperature (296 K) for different mixtures of H2O in N2 and 2.107 molecules from a five-sites potential. The results show that the auto-correlation functions expected exponential decay behavior [i.e. v v t exp( ) τ      ] and from the decay times τv , the mass diffusion coefficient and the velocity changing collisions frequency have been determined. The comparison between the CMDS results and experimental results are presented and discussed.