Avances en la estimacion de la resistancia de catamaranes (Progress in multihull resistance estimation)

The catamaran type hulls have been used since remote times; however, they have almost always been restricted to minor ships. A massive growth of these kinds of vessels has been noted recently in the ferry industry, for sporting vessels and pleasure. The use of compound materials and of aluminum, added to greater power, has allowed that the ranges of operations are developed at high speeds. One of the challenges which naval architects who project these vessels must face, is to estimate with enough precision, the hull resistance to drag, a task which is not trivial at all because until today, a certain degree of uncertainty remains, particularly due to the interaction that is possible to notice between them. In the present study, the progresses in the methods of evaluation of the drag in multi-hull ships, particularly that of a catamarans, obtained by computational fluids dynamics -CFD-, and through tests in a hydrodynamic testing canal carried out by the Universidad Austral of Chile. Besides, a method based on equations of regressions is presented for the calculation of the drag coefficient of waves for catamarans with round hulls in a regime of semidisplacement speed.