Simulation on Formation Mechanism, Crystal Structure and Formation Condition of Methane Hydrates by Molecular Dynamics Method

From the point of view of energy sources, natural gas hydrates will be in an important position as a potential future energy resource and as a basis of storage and transportation of natural gas. The main constitute of natural gas is methane. As the fundamental research, the molecular mechanism of methane hydrate formation is investigated using a molecular dynamics method. The criteria of formation of the hydrate are that a hydrate structure is formed when a system reaches to an equilibrium state. Computer simulation results show that methane hydrate of type I is formed from 0K to 274K under a definite density in which 368 water and 64 methane molecules are contained in a cubic cell of length 24.0Å. At 320K, instability starts to emerge in the hydrate structure. It is successfully simulated that the equilibrium pressure is increased with the temperature increasing for the hydrate.