Sidebranching in Solutal Dendritic Growth

Abstract

Dendritic growth in solidification is one of the most studied problems in branching morphogenesis [1,2]. In this contribution we study sidebranching induced by fluctuations in dendritic growth. We compute the amplitude of sidebranching induced by internal (equilibrium) concentration fluctuations in the case of solidification with solutal diffusion. This amplitude could be too small to explain previous experiments. We investigate the effects of other possible sources of fluctuations (of external origin) by introducing a non-conserved noise in a phase-field model. Results reproduce the characteristics of sidebranching found in both experiments and theory. The way noise is introduced in the phase-field model appears to be qualitatively fair in order to investigate sidebranching phenomena in experiments where this is due to the selective amplification of noise, regardless of its origin.