M.Sc. Tezi Görüntüleme | |||||||||||||||||||||
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| Summary: Turkish fishing vessels have handicaps which may be considered significant in terms of resistance and propulsion. Therefore they are equipped with more powerful engines than normally required. Yet, they could not reach the desired speed due to the inadequate hull forms. Since there is not enough scientific data, there are applications of superficial bulb installations on fishing vessels which could not improve the situation. In this study, Delta (∆), Nabla (∇) and Elliptical (O) shaped bulbs are implemented to ITU Fishing Boats Series hull forms of 148/3, 148/4, 148/8 and 148/9 in order to determine the most appropriate bulbous bow for fishing vessels. Initially, in defined Fn values, CFD analyses on four main forms are performed by using Realizable k−ε Model and VOF method. The total resistance values obtained by the CFD analyses and by the existing experiment results via Froude and Hughes methods are compared and examined. Thus, the methods and reference values of CFD analyses are determined for the hull forms with bulbs which do not have experiment results. Subsequently, the CFD results of frictional resistance, pressure resistance and total resistance values for actual hulls and hulls with bulbs are compared.Following the examination of results in terms of CB, L/B and bulb types, it is determined that the elliptical bulb type is the most suitable bulb type for the fishing vessels. Key Words: Fishing boats, bulbous bow, computational fluid dynamics, resistance
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