Aerodynamic Study of Pyramid Stacking Configuration on Mega-Sized Container Ships Using CFD to Optimize Lateral Drag

Container shipping has become a cornerstone of global trade over the recent decades, while the container ships size has leveled up to over 20000 TEU. Despite a vast windage area, the studies on mega-sized container ships have been focused on the hydrodynamics characteristics, whereas the aerodynamic features have been neglected. The alarm was raised in March. 2021, when EverGreen, a 20000-TEU container vessel, went aground under gale in the Suez Canal, and one of the arteries of the world trade was blocked temporarily. Although the studies on huge container ship stacking configurations have been carried out by a few scholars, the aerodynamics of pyramid stacking configuration, as the most common loading practices, have not been appreciated. Henceforth, the present research aims to give an insight into the case by examining different cross-sectional pyramid profiles in 2D and 3D simulations using the commercial CFD package STARCCM+. Given the impact of maximal windage area on the interoperability and maneuvering efficiency of the container ship, the lateral drag has been studied, where the flow field is modeled by the RANS equations and the realizable K- ɛ turbulence model. The objectives are threefold; the first is to analyze the applicability of 2D simulation for this case. The second is to scrutinize the flow behavior in different pyramid stacking profiles. The last is to propose some guidelines for pyramid loading practice. According to the outcomes, an optimum pyramid configuration reduced a ship's lateral drag by 22.1% compared to the full-load profile while saving 384 TEU compared to the conventional pyramid models and could substitute the old-fashioned loading practice.