摘要
Molecular-dynamics(MD)simulations have been performed for the growth of a spherical methane-hydrate nano-crystallite,surrounded by a supersaturated water–methane liquid phase,using both a hybrid and globalsystem thermostatting approach.It was found that hybrid thermostatting led to more sluggish growth and the establishment of a radial temperature profile about the spherical hydrate crystallite,in which the growing crystal phase is at a higher temperature than the surrounding liquid phase in the interfacial region,owing to latent-heat dissipation.In addition,Onsager’s-hypothesis fluctuation–dissipation analysis of fluctuations in the number of crystal-state water molecules at the interface shows slower growth.
Molecular-dynamics(MD) simulations have been performed for the growth of a spherical methane-hydrate nano-crystallite, surrounded by a supersaturated water–methane liquid phase, using both a hybrid and globalsystem thermostatting approach. It was found that hybrid thermostatting led to more sluggish growth and the establishment of a radial temperature profile about the spherical hydrate crystallite, in which the growing crystal phase is at a higher temperature than the surrounding liquid phase in the interfacial region, owing to latent-heat dissipation. In addition, Onsager’s-hypothesis fluctuation–dissipation analysis of fluctuations in the number of crystal-state water molecules at the interface shows slower growth.
基金
the Irish Research Council for Government-of-Ireland postdoctoral fellowship, under grant no. GOIPD/2016/365
