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An experimental study was carried out to evaluate still water performance of a Systematic Series of hard chine hulls in planing and semiplaning speed range. Models of the Naples Systematic Series (NSS) were of varying length-to-beam ratios of the parent hull. The parent hull, shaped with warped bottoms, was derived from a pre-existing hull extensively tested in a towing tank. This hull was validated by many work boats built in the last fifteen years. To simplify the construction of vessels with rigid panels (aluminium alloy, plywood or steel) the original hull form was transformed to obtain developable hull surfaces. The models were tested at Re>3.5×106, in speed ranges Fr=0.5−1.6 and Fr∇=1.1−4.3. The series studies the influence of LP/BC and Ⓜ ratios that vary respectively in the ranges of 3.45–6.25 and 4.83–7.49, for two positions of CG. All the models were tested both with and without interceptors. To enable model-ship correlation following the ITTC recommendations, in addition to the resistance coefficients of the models, dynamic wetted lengths and surfaces were provided as tables. To facilitate the implementation of Velocity Predict Programs, all the data (resistances, lengths and surfaces) were also furnished in polynomial form. In addition to the use of series in the design field, this study was done to provide data to improve the numerical simulations of a planing craft. With this aim, in addition to the resistance data, the wave profiles, obtained by wave cuts, were provided to carry out validation procedures

In the context of marine application of computational fluid dynamic (CFD), it is well known that the numerical simulations of planing craft are significantly less reliable than that of displacement ships. For this reason, it is important to perform a comprehensive approach to the verification and validation (V&V) methodology and procedures for simulating CFD planing craft. In the first part of this paper, an assessment of the accuracy and effectiveness of different simulation setups and techniques for planing craft is performed. In the second part, the results of the V&V study are reported for three different hull models at four Froude numbers (Fr). The Unsteady Reynolds-Averaged Navier-Stokes code results were validated using benchmark experimental data obtained for three hull models characterized by systematic variation of the length to beam ratio. Grid independence, iteration, and time-step convergence analysis for response variables (resistance coefficients, wetted surfaces, and dynamic trim angles) were conducted using the main error and uncertainty estimation methods available in the literature. The same procedures were followed for the profiles of the wave patterns. The results showed that there was improved reliability of the numerical simulation of the planing craft in terms of the errors and uncertainties, related to the predictions of resistance, running attitude, and wave pattern. The results of the V&V study highlighted the fact that modeling of the planing

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