chapter  21
10 Pages

Wake of a catamaran navigating in restricted waters

ByG.T.P. McSullea, J.M. Rodrigues, C. Guedes Soares

High speed catamaran ferries are used throughout the world in confined waters, such as rivers and ports. Wake from these and other small vessels has a variety of effects on the waterways, including deterioration of banks, damage to structures and other vessels, and danger to people close to the shore. A CFD study of the effects of hull characteristics on the wave height and wave energy of the wake wash was undertaken. The hulls were varied using the design of experiments methodology so that the main effects of each hull factor could be analysed with a reduced number of tests. A secondary study was also undertaken focussing on the effect of vessel speed and water depth on wave height and wave energy. Design of experiments analysis highlighted that of the four factors (beam, demi hull beam, bow keel rake and bow entry angle) demi hull beam had the largest effect on the wave heights and wave energy. It was also shown that increasing the vessel speed resulted in increased wave heights and wavelengths. Furthermore, the reduction in water depth resulted in an increase in wave heights.