This paper presents the comparative study carried out for focused waves interaction with the fixed cylinder in ISOPE 2020. The paper discusses qualitative and quantitative comparison between 20 different numerical solvers from various universities across the world for a fixed cylinder. The moving cylinder cases are reported in the companion paper as Part B. The numerical solvers presented in this paper are recent state of the art in the field, mostly developed in-house by various academic institutes. Majority of the participants used hybrid modeling, i.e. a combination of potential flow and Navier-Stokes solvers. The qualitative comparison based on the wave probe and pressure probe time histories and spectral components between laminar, turbulent and potential flow solvers are presented in this paper. Furthermore, the quantitative error analysis based on the overall relative error in peak and phase shift in the wave probe and pressure probe of all the 20 different solvers are reported. The quantitative error with respect to different spectral component energy level (i.e., in primary, sub and super harmonic region) capturing capability are reported. Thus, the paper discusses about maximum, minimum and median relative error present in the recent solvers for application to industrial problems rather than attempting to find the best solver. Further, recommendations are drawn based on the analysis.

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Bow shape has been recognized as an important factor influencing the seakeeping performance and added resistance of ships. This paper presents a numerical comparative study on added resistance and seakeeping of model ships with ‘X-bow’ and a wave-piercing monohull in regular head waves using a computational fluid dynamics (CFD) software. Different wave heights, wavelengths and forward speeds are considered in the systematic investigation in order to characterize the added resistance and wave-induced motions, and to explore the local wave patterns. The results show a considerably different hydrodynamic characteristic by different bow shapes.