Research On Multi-hull Configuration Based On New Slender Ship Theory

Multi-hull ships (catamaran, trimaran, pentamaran, etc), which offer many hydrodynamic and layout advantages, are attractive options for ship designers .But the Multi-hulls have a main problem of their sub-hull's complex configuration. Besides this, the dimension of main hull and sub-hulls, hull type and displacement also have effects on the calculation of wave-making resistance. At the same time, fiction-resistance and flow-blocking effect must be considered when solving the problem of Multi-hull's configuration. So, in this thesis, the relationship between Multi-hulls' configuration and its wave-making resistance will be discussed.Firstly, the Noblesse Slender Ship Theory was introduced briefly, and by means of amelioration, this theory was applied to numerical calculation. Based on this theory, where the variables are separated by expanding exponential function, the wave resistance formulae of a multi-hull is obtained.Secondly, taking catamaran for instances, the coefficient of catamaran's wave-making resistance were calculated and the numerical results coincide well with that of the model test. So, the feasibility of the new slender ship wave resistance theory is proved and can be applied to calculate the high-speed multi-hull's wave resistance.Thirdly, based on the validate calculation of catamaran's wave resistance, the new slender-ship wave resistance theory is applied for the wave resistance calculation of the trimaran and pentamaran, from which some useful conclusions were obtained.