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A numerical environment for efficient assessment of ship resistance using CFD is presented in this paper. Predicting ship resistance in calm water with the Naval Hydro Pack can be performed within a few hours, including grid generation, computation and post–processing of results. Being able to rapidly predict ship resistance renders CFD a cost-effective design tool, since a hull form designer can evaluate multiple variants of hull geometry quickly. The process of setting up, running and post-processing is accelerated by automating the process to a high level, significantly decreasing the number of manual work effort. In this paper the capabilities of the Naval Hydro Pack are demonstrated by calculating steady resistance for three different benchmark hull forms, where time for pre- processing, processing and post-processing is reported. On average, it took two and a half hours to obtain steady state results per hull form, including set–up, computational time and data analysis. Results are validated against available experimental data s

This work describes a novel method to calculate resistance force at steady forward motion with free-surface simulation using the viscous turbulent flow model in Volume-Of-Fluid (VOF) formulation. Assuming quasi steady-state solution, equations for fluid flow and free-surface motion are decoupled due to separation of time-scales. It is thus possible to increase the time-step size by about 3 orders of magnitude and preserve numerical stability, which gives a substantial increase in computational efficiency. The method has been implemented and tested in FOAM-Extend, a fork of the OpenFOAM software. KCS and DTMB hull geometries are simulated with the novel method and results are compared with experimental data. The accuracy is equal to simulations with a conventional transient approach. Performance and parallel scalability are assessed. The results show that the novel method delivers substantially increased computational efficiency without sacrifice of accuracy.