J053012 量子効果が低温水素の熱・輸送物性メカニズムに与える影響の分子動力学的解析(〔J053-01〕マイクロ・ナノスケールの熱流体現象(1))

Abstract

In this study, we conducted analysis of quantum effect of the hydrogen molecules on the p-V-T relation of cryogenic hydrogen using classical Molecular Dynamics (MD) and path integral Centroid MD (CMD) method. We performed MD simulation across a wide temperature region in the constant density and compared the pressure formulations of each method. In addition, we calculated the diffusion coefficient using Green-Kubo method. As a result, it was confirmed that classical MD cannot reproduce the experimental data in the low temperature region and underestimates the virial pressure compared to the CMD. Moreover, it was clarified that taking the quantum effect into account produces broader repulsive region and shallower the potential well. Because of this mechanism, the intermolecular interaction of hydrogen diminishes and the virial pressure increases. In addition, it was confirmed that the diffusivity increase compared with classical representation.