Mechanisms for thermal conduction in hydrogen hydrate

• Published in: The Journal of Chemical Physics
• Main Authors: English, Niall J., Gorman, Paul D., MacElroy, J. M. Don
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Institute of Physics 2012
• Subjects: Molecular dynamics; Thermal conductivity; Green-Kubo; Hydrogen hydrate; Hydrates; Hydrogen; Canada; Methane hydrate
• Online Access: http://hdl.handle.net/10197/3495; https://doi.org/10.1063/1.3677189

Extensive equilibrium molecular dynamics (MD) simulations have been performed to investigate thermal conduction mechanisms via the Green-Kubo approach for (type II) hydrogen hydrate, at 0.05 kbar and between 30 and 250 K, for both lightly-filled H2 hydrates (1s4l) and for more densely-filled H2 systems (2s4l), in which four H2 molecules are present in the large cavities, with respective single- and double-occupation of the small cages. The TIP4P water model was used in conjunction with a fully atomistic hydrogen potential along with long-range Ewald electrostatics. It was found that substantially less damping in guest-host energy transfer is present in hydrogen hydrate as is observed in common type I clathrates (e.g., methane hydrate), but more akin in to previous results for type II and H methane hydrate polymorphs. This gives rise to larger thermal conductivities relative to common type I hydrates, and also larger than type II and H methane hydrate polymorphs, and a more crystal-like temperature dependence of the thermal conductivity. Science Foundation Ireland Other funder Ireland Canada University Foundation Royal Irish Academy au, ti, ke, ab, is - TS 01/02/2012