COMPARISON OF EXPERIMENTAL METHODS FOR DETERMINING WAVE PATTERN RESISTANCE OF A TRIMARAN BASED ON WAVE MEASUREMENTS IN LONGITUDINAL CUTS

Article type: Research Article

Authors: Degiuli, Nastia | Werner, Andreja | Doliner, Zdravko

Affiliations: University of Zagreb, Faculty of Mechanical Engineering and Naval Architecture Zagreb, CROATIA

Abstract: The Landweber, Hogben and Baba methods of experimental determination of wave pattern resistance based on wave height measurements in several longitudinal measurement cuts have been introduced in this paper. The programme of numerical simulation and experimental determination of wave pattern resistance was conducted in a tank of finite width and infinite depth for a trimaran whose individual hulls are Wigley parabolic models, for the Froude number range 0.254–0.420, with a total of 12 runs. The above mentioned methods are based on an identical hydrodynamic model, and identical analytic expressions. A comparison of the calculation results (amplitude spectrum, wave resistance, reconstructed waveforms) is given by numerical simulation of experimental determination of wave pattern resistance. It has been shown that all three methods are equal and that they give the same results if criteria based on frequency content determination and resolution in frequency are respected. Experimental determination of wave pattern resistance by applying the same methods and respecting the same criteria was carried out and results show the consistency of the basic approach. Calculation of theoretical wave resistance based on the linear wave theory and Michell's approximation of ship's hull has been carried out, whereby the comparison between theoretical predictions and experimentally determined wave pattern resistance has shown poor agreement.

Journal: International Shipbuilding Progress, vol. 50, no. 1-2, pp. 57-87, 2003