Molecular dynamics simulation of surface vaporization in beryllium plasma facing components

An important feature of beryllium is its high vapor pressure. Small fluctuations in beryllium vapor pressure produce non-negligible differences in thermal behavior of Plasma Facing Components under high heat flux exposure, during off-normal events and Edge Localized Modes. On the basis of an available pair potential, classical Molecular Dynamics (MD) Simulations have been carried out in order to evaluate beryllium vapor pressure and latent heat of vaporization under tokamak conditions. Results from Molecular Dynamics Simulations show a good agreement with the experimental value for the latent heat of vaporization. Vapor pressure, evaluated through Clapeyron's equation on the basis of simulations results, is affected by more uncertainties and shows a poor agreement with the available experimental data. (c) 2007 Published by Elsevier B.V.