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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 paper presents detailed validation and verification study for the KCS in calm water conditions. Validation is performed by comparing the resistance, sinkage and trim with experimental data for six Froude numbers, while verification is performed for each case by assessing grid and iterative uncertainties. A single set of governing equations for water and air is used where jump conditions at the free surface are used to discretise discontinuous density and dynamic pressure fields. Volume of Fluid (VOF) method is used for interface capturing, and the k-omega SST model is used for turbulence modelling. Ship motion is solved with quaternion based six degrees-of-freedom (6 DOF) rigid body motion equations. The method is implemented in the Naval Hydro pack based on foam-extend, a community driven fork of OpenFOAM software.

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.