Microscale trapped air bubble in ice: From physics to applications

Ice is an ancient and ubiquitous material widely found in both natural environments and industrial applications. Defects related to air bubbles in ice often significantly influence the morphological evolution of interfaces, thereby influencing its performance in various contexts. To gain a deeper understanding of the mechanisms underlying trapped air bubbles in ice, this paper systematically summarizes their formation conditions, growth processes, distribution characteristics, and application areas from both microscopic and macroscopic perspectives. The results indicate that the distribution of bubbles with different shapes in ice is closely related to the freezing rate. When the freezing rate exceeds 25 μm/s, egg-shaped bubbles form in the ice. Furthermore, bubbles enhance the flow around the ice, thereby accelerating its melting rate in water or air. The weakening effect of trapped air bubbles on the strength of ice is inversely proportional to the bubble volume fraction raised to the power of 2/3. Based on a systematic review of existing research on trapped air bubbles, the current research gaps are also identified, and future development trends are discussed. Elucidating the characteristics of trapped air bubbles in ice contributes to a deeper understanding of freezing mechanisms and provides theoretical references for ice-related engineering applications.