An Efficient Method for Design and Powering Prediction of Fast Slender Catamarans

This paper presents a parameterized and mathematically defined hull shape that can be tuned to represent modern passenger fast ferries. Additionally, a resistance calculation model for high-speed slender round-bilge catamarans is presented. The resistance model builds on established theory, but incorporates novel contributions in the modeling of the wake hollow downstream of transom sterns and the form factors of slender catamarans. To generate systematic data on wake hollow length and form factors, 3D RANS simulations are employed, and the suggested models are evaluated by comparing them with these simulations. A validation study is conducted, indicating that the resistance model can provide accurate results for typical fast ferry catamaran hulls at design draft and reduced drafts. Furthermore, it is shown that the combination of the proposed hull geometry and resistance calculation models can yield reliable predictions for the power requirement of existing vessels. This enables accurate power prediction in cases when limited hull geometry information is available. The hull geometry model is made available through open-source code.