Emmanuel Duffour

Effects of dielectric material on arc plasma pressure and ablation measurement in high-power apparatus

We measure some characteristic parameters to investigate the electrical discharge in different types of insulators in the energy range 150-500 J. By varying the type of insulator and the confining geometry, we quantify their specific influence on the pressure, the dissipated energy, and the ablated mass. These considerations are useful to increase the knowledge of the physical mechanisms which play a role in the high-current plasma-wall interaction. In agreement with previous theoretical works, we show two opposite behaviors between polyethylene and polyoxymethylene in terms of ablated mass and graphite formation.

Structure and thermodynamic properties from molecular dynamics simulations of the polyethylene crystal

This paper describes the results of molecular dynamics simulations of polyethylene crystal at two temperatures in the absence of periodic boundary conditions. We report the profiles of the temperature and pressure tensor along two directions in the crystal. We check that the two different methods (IK) and (MOP) for calculating the pressure tensor give similar profiles, which are constant in the middle of the crystal. In addition, we compare the data resulted from the pressure profiles with the values obtained from the virial route. The internal structure of the polyethylene is visualized through the intramolecular and intermolecular radial distribution functions.