Saffman-Taylor fingers at intermediate noise.

Abstract

We study Saffman-Taylor flow in the presence of intermediate noise numerically by using both a boundary-integral approach as well as the Kadanoff-Liang modified diffusion-limited aggregation model that incorporates surface tension and reduced noise. For little to no noise, both models reproduce the well-known Saffman-Taylor finger. We compare both models in the region of intermediate noise, where we observe occasional tip-splitting events, focusing on the ensemble-average. We show that as the noise in the system is increased, the mean behavior in both models approaches the cos^{2}(πy/W) transverse density profile far behind the leading front. We also investigate how the noise scales and affects both models.