Abstract:
The thesis presents a potential based boundary element method for calculating the flow
around the multihull ships moving with a uniform speed in unbounded water. The ship-wave
problem is a non-linear one due to the non-linear nature of free surface boundary condition.
In order to solve the problem, the free surface condition is linearized first about the mean
water level by the systematic method of perturbation in terms of a small parameter. The
distributions of singularities on the surfaces are determined by satisfying the linearized free
surface condition and the kinematic conditions on the hull surface respectively. The
circulation is introduced to generate lift by distributing doublets on the wake surface and is
determined by applying the Kutta condition at the trailing edge of the lifting part.
The present method has been applied to a number of multihulls for various Froude numbers
and is found to be efficient for evaluating flow field, wave pattern and wave making
resistance in unbounded water.
