Hydrodynamic Optimisation of High-Speed Trimaran Hull Forms

摘要

This paper presents experimental data and numerical computations for two trimaran hull forms for high speed transportation: one with round bilge component hulls and one characterized by a hard-chine main hull. The experimental data concern residual resistance results systematically collected for a grid of configurations of both hull forms. The numerical analysis, carried out on the same grid, is aimed to the assessment of the capability of a boundary element method to comply with the physical results related to a complex marine vehicle as the trimaran which involves appreciable interference problems of the free surface pattern around the component hulls. In addition a numerical optimisation is presented which was attempted to individuate the best position of the side hulls by coupling the boundary element method with a sto-castic optimisation process similar to genetic algorithms. The search of the best configuration had the objective of minimizing wave resistance in the two-dimensional space describing the side hull positions.