Resistance analysis of unsymmetrical trimaran model with outboard sidehulls configuration

Abstract

The application of multi-hull ship or trimaran vessel as a mode of transports in both river and sea environments have grown rapidly in recent years. Trimaran vessels are currently of interest for many new high speed ship projects due to the high levels of hydrodynamic efficiency that can be achieved, compared to the mono-hull and catamaran hull forms. The purpose of this study is to identify the possible effects of using an unsymmetrical trimaran ship model with configuration (S/L) 0.1–0.3 and R/L=0.1–0.2. Unsymmetrical trimaran ship model with main dimensions: L=2000mm, B=200 mm and T=45 mm. Experimental methods (towing tank) were performed in the study using speed variations at Froude number 0.1–0.6. The ship model was pulled by an electric motor whose speed could be varied and adjusted. The ship model resistance was measured precisely by using a load cell transducer. The comparison of ship resistance for each configuration with mono-hull was shown on the graph as a function of the total resistance coefficient and Froude number. The test results found that the effective drag reduction could be achieved up to 17% at Fr=0.35 with configuration S/L=0.1.

Keywords

trimaran model / unsymmetrical hull / ship resistance / stagger / drag reduction

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