Abstract:

The physical mechanism of crystal growth was analyzed using heat and mass transfer equations, Navier-Stokes equations and growth dynamics in this paper. Cellular automata (CA) method was used to form a phase change model. The desublimation process of water vapor and CO₂ in liquid methane is observed by computer simulation. Not only the two-dimensional simulation results of ice crystal growth, but also the two-dimensional and three-dimensional simulation results of CO₂ crystal growth in liquid methane were obtained. Results show that this model could simulate water and CO₂ crystallization under sub-cooled and supersaturated environment. The two-dimensional ice crystal result is very similar to the real ice crystal with topological structure. CO₂ crystal has simpler structure and the simulation results confirm to the characters of authentic CO₂ crystal. This model can be improved to analyze the water and CO₂ crystallization in liquid natural gas (LNG) and may be used to improve the technology processes of storage, transportation and utilization of LNG.