Two strategies are pursued to find optimum value of design variable: trimaran hull transformation and separated hull approach. Subsequently, D-optimal method is used for finding the best parameters to achieving minimum resistance at cruise and sprint speeds. It is then necessary to compute the ship resistance of the reconstructed geometry which is hereby accomplished by slender body method. Considering the fixed displacement volume, the values of the longitudinal center of buoyancy, block coefficient, midsection coefficient as well as the side hull length and position are computed and using Lackenby shift transformation, the geometry is reconstructed during the optimization process. In the current paper, different geometrical parameters of the trimaran hull ship are investigated to achieve the optimal points of geometry parameters. Numerical experiments indicate that rotating the shoulders towards the surface is more influential than the feet, demonstrating the impact of the upper body on wave resistance. 10 Truncating the swimmer’s body at the upper thigh increases the wave resistance at speeds below 2.0m/s but is not significant at higher speeds, indicating that the upper body is the main contributor to the wave system. Larger swimming pool dimensions are shown to be significant at reducing wave resistance at speeds above 2.0 m/s and depths below 0.40m. Numerical simulations agree with experiment to confirm that there were negligible reductions in wave resistance below a depth of 0.40m. The drag and wave pattern of a female swimmer mannequin were experimentally measured over a range of depths from 0.05m to 1.00m at a speed of 2.50 m/s. This research experimentally validates the use of thin-ship theory for quantifying the 5 wave resistance of a realistic swimmer geometry. Previous experiments have inferred how immersed depth influences the drag acting on a swimmer, but have not directly quantified the magnitude of wave resistance. Quantifying the wave resistance of a swimmer as a function of depth assists in identifying the optimum depth for the glide phases of competition. It's confirmed that the developed Rankine panel method is accurate and robust. An NPL 3b catamaran hull is selected to verify the applicability of the present method in the catamaran hull. The computed results of the resistance, wave profile behind the transom stern, and wave pattern around the hull obtained by RPM with TS treatment are validated by comparing them with CFD and EFD results. Besides, a computational fluid dynamics (CFD) method based on Star-CCM+ is employed to study the flow around NPL 3b and 5365 hull. RPM incorporated with FB model is applied to evaluate the wave-making resistance of the NPL series hull. The results of resistance and wave profiles show good agreement with experimental data.įor a transom-stern hull, two numerical treatments including false body (FB) and three different forms of transom stern conditions (TS) are developed to model the influence of flow separation. A validation study on both mono-hull and catamaran of Wigley hulls is carried out firstly. In the present study, a Rankine panel method (RPM) based on high-order boundary element method is implemented in an in-house Fortran code to solve the steady wave problem of high-speed ships. The method presented offers orders of magnitude saving in computational effort over the higher-order methods without sacrificing accuracy. Good correlation with both experiment and higher-order methods have been found for the slender hull forms investigated. Comparisons have also been made with results obtained from higher-order panel codes. Particular attention has been made to the closure of the model in the region of the transom stern and results have been compared with experimental measurements carried out by the authors. The bodies are represented by planar arrays of sources on the local hull centre-lines. The model has been developed specifically for calculating the wave pattern resistance of slender catamaran hulls with transom sterns, but may be applied to more general ship hull-forms provided that they have sufficiently high Length:Breadth ratio. A potential, non-lifting, model has been used with linearised free surface conditions to describe the flow around a body in a finite channel. An existing numerical method for calculating the wave pattern and hence wave resistance of a body moving in a free surface has been improved and developed.
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