Nonisothermal cellular automata simulation of two-dimensional snow crystal growth.

Abstract

Natural snowflakes exhibit remarkable diversity with a fascinating sixfold symmetry and fractal structure. Efforts to discover the snow crystal growth pattern and mechanism behind it have been made in the past 50 years. Among those, cellular automata (CA) have made certain progress. To investigate the influence of latent heat release in snow crystal growth and have a deeper understanding of crystal growth characteristics, an improved CA model combined with vapor diffusion and heat diffusion is proposed to investigate the snowflake growth process in a two-dimensional and nonisothermal field in this paper. Simulation results show that obtained snow crystal growth behavior is consistent with previous experimental observations and satisfies the crystal growth dynamic theory. Latent heat release impacts the small structure of snow crystals, and it could have a more significant influence on snowflake morphology when vapor diffusion is slow and heat diffusion is dominating.