| The speeding up of waterway transportation is one of the important tendencies ofmodern transportation development. With the progress of the technology, high-speedvessels developed dynamically over the last decades. One of the key problems ofhigh-speed vessels' design lies in the forecast of their resistance qualities. From theprinciple of naval architecture we know, ship resistance can be divided into threeparts: friction resistance, viscous pressure resistance and wave-making resistance. Forhigh-speed vessels, wave-making resistance predominates in their total resistance.How to predict the wave-making resistance and wave pattern of the high-speedvessels by numerical computation methods precisely, is one of the important part anddifficulties in the research of wave-making resistance theory, meanwhile, it is also thekey point of some engineering problems such as the optimization of ship form.Typical transom flow occurs for a displacement ship with a transom-stem at asufficiently high speed, usually F_n＞0.4. The effect of "virtual appendage" behind atransom stern can conduce to small resistance, therefore, transom stern is almost thecommonly adopted stern form of displacement-type high-speed vessels. For manyyears, the numerical computation of wave-making problem about displacement-typehigh-speed vessels with a transom stern is a subject which is challenging and ofengineering practical value. The reseach concerned focuses on the treatment withtransom stern boundary condition and its correlation numerical computation.Moreover, the research of the flow about transom-stem and its effect on wave-makingresistance is still an important direction of the research about ship resistance theory.The numerical calculation of wave resistance by a raised panel method based onNURBS (Non- Uniform Rational B-Splines) for high speed ships is discussed. In thisthesis, NURBS is not only used to represent the body geometry and disturbed freesurface(wave pattern) but also employed to represent and the unknown sourcestrength distribution on panels of bode surface and above free surface. The sourcestrengths are determined by satisfying the body surface boundary condition, the linearity free surface boundary condition and other boundary conditions, such asshallow water boundary condition and transom stem boundary condition. In thesystem of linear equations, the direct variable becomes the control points of theunknown surface which source strength distributed on. Hence, the velocity potential,the wave pattern and the wave resistance could be obtained. In this thesis, Rankinesource is employed as singularity. Raised panels above the free surface combinedwith collocation-point shifting up-stream, can expediently satisfy the radiationcondition numerically. Besides, transom stem boundary condition is satisfied by thecondition of smooth flow off the transom edge tangentially.Wigley hull and NPL Model 100A hull is selected as a common computationalexample. The wave making resistance and wave patterns of Wigley mono-hull, NPLmono-hull in deep and shallow water and Wigley catamaran hull, NPL catamaran hullin deep water are calculated respectively.
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