Examining the effect of Reynolds number and flow time on the dynamics of scallop formation beneath an ice block

Melting processes in floating glacier ice, such as icebergs and ice islands, can lead to the formation of distinctive surface features, including scallops-cusped, undulating structures that develop as these ice masses melt in oceanic environments. These features, observed in both the Arctic and Antarctic, have attracted significant scientific interest due to their role in ice dynamics and mass loss. This study experimentally investigates the mechanisms behind ice scallop formation by examining the effect of approach Reynolds number on ice melt patterns. Ice specimens were placed in a recirculating rectangular flume to simulate natural melting conditions. The experiments were conducted at three Reynolds numbers (2.30 × 10 4 , 3.00 × 10 4 , and 3.30 × 10 4 ) to examine the influence of fluid flow on scallop development. The results showed three phases of scallop formation with increasing Reynolds number: an initial flat surface, a fully developed scallop, and an evolving scalloped geometry. Notably, the water was allowed to flow along the side of the ice block, which led to a three-dimensional melting effect. This revealed that lateral melt rates significantly influenced the overall melt rate in the mid-plane of the ice specimen. The results also showed that an increase in the Reynolds number corresponded with an increased melt rate, suggesting that higher flow velocities enhance the formation of scalloped structures. These findings provide deeper fundamental insight into the complex interactions between fluid dynamics and ice melting, with implications for understanding ice mass loss in polar environments.