Objectives To address the impact of ice-covered environments on ship performance and the limitations of traditional optimization methods based on empirical formulas for ice resistance, a precise ship design optimization method based on CFD & DEM is proposed to optimize both ice resistance and calm water resistance.

Methods Firstly, calm water resistance and ice-breaking resistance are calculated based on CFD and CFD & DEM methods, and an innovative HMIGA algorithm is introduced to simulate realistic ice fields. Then, an efficient surrogate model is established using XGBoost, followed by the execution of the NSGA-III algorithm for optimization. Finally, the method is validated using the KCS standard model.

Results The results shows that the optimized ship design achieves a 10.58% reduction in ice resistance and a 2.32% reduction in calm water resistance. The optimized ship experiences lower peak loads and further reduces ice resistance by generating waves to push away floating ice.

Conclusions The proposed method comprehensively considers the effects of flow field and ice field randomness on optimization results, leading to more accurate and effective improvements in ship ice resistance and calm water resistance. The introduction of HMIGA and XGBoost enhances the practical application of the method, providing valuable guidance for future optimization designs of ships operating in ice-covered environments.