Scaling Behavior of Sloshing Impact Pressures Based on Event Distribution and Regime Classification

Sloshing in partially filled tanks generates significant impact pressures that threaten the structural integrity of LNG cargo containment systems, and accurate scaling of these impacts remains a critical issue. Although Froude-based scaling has been widely applied, its validity may be limited under conditions where multiple impact mechanisms coexist. In this study, sloshing impact pressures measured across different scales were analyzed based on individual impact events. Distribution-based representative metrics, including mean and upper-percentile values, were introduced, and scale dependency was quantified using a power-law relationship. The results show that under low filling conditions, impact responses exhibit relatively consistent distributions, and gravity-based scaling yields nearly scale-independent results. In contrast, high filling conditions lead to increased variability and a pronounced expansion of the upper tail, resulting in stronger scale dependency, particularly for high-intensity events. The increase in the power-law exponent indicates that extreme impacts are more sensitive to scale variation. These findings demonstrate that sloshing impact scaling is governed not by a uniform change in pressure magnitude, but by a redistribution of impact intensity across events. Consequently, reliable scaling requires consideration of both distribution characteristics and underlying impact mechanisms.