关键词: sI型甲烷水合物;分解速率;分子动力学

Abstract: Methane hydrate contains high purity methane and water, which is an important strategic resources that can effectively relieve the energy crisis.Methane hydrate decomposition dynamics research involving the hydrate exploitation and application of hydrate technology is the focus of scholars around the world.This article adopts the method of molecular dynamics simulation, style I methane hydrate decomposition kinetics was studied, and the effect of temperature on the microstructure and decomposition rate was discussed.Style I methane hydrate is the object of research, and the influence of temperature on water molecule sequence parameters and radial distribution function was studied.The result shows that in the process of hydrate decomposition, water molecules structure is evolved from the original long range order to long-range disorder and short-range ordered, and is converted from crystal structure of low density to liquid water of higher density.As the temperature of system increases from 270 K to 295 K, the first peak of radial distribution function of carbon-carbon atoms of methane molecules shows a trend of increase, shows that the higher the temperature, the faster the rate of methane escape out of the cage.The study found that in the process of decomposition dynamics of evolution, the AOP sequence parameters of water molecules begin to rise from 0, eventually to stabilize near 0.8.The higher the temperature, the steeper the curve in decomposition of AOP, the faster decomposition of methane hydrate.

Key words: Methane hydrate contains high purity methane and water, which is an important strategic resources that can effectively relieve the energy crisis.Methane hydrate decomposition dynamics research involving the hydrate exploitation and application of hydrate technology is the focus of scholars around the world.This article adopts the method of molecular dynamics simulation, style I methane hydrate decomposition kinetics was studied, and the effect of temperature on the microstructure and decomposition rate was discussed.Style I methane hydrate is the object of research, and the influence of temperature on water molecule sequence parameters and radial distribution function was studied.The result shows that in the process of hydrate decomposition, water molecules structure is evolved from the original long range order to long-range disorder and short-range ordered, and is converted from crystal structure of low density to liquid water of higher density.As the temperature of system increases from 270 K to 295 K, the first peak of radial distribution function of carbon-carbon atoms of methane molecules shows a trend of increase, shows that the higher the temperature, the faster the rate of methane escape out of the cage.The study found that in the process of decomposition dynamics of evolution, the AOP sequence parameters of water molecules begin to rise from 0, eventually to stabilize near 0.8.The higher the temperature, the steeper the curve in decomposition of AOP, the faster decomposition of methane hydrate.