CFD Analysis into the Drag Characteristics of Trimaran Vessel: Comparative Study between Standard NPL 4a and the use of Axe-Bow

Abstract

Recently, there has been an increased demand for multihull vessels for military and commercial applications. This demand for multihull vessels is to balance speed with payload requirements. One such hull form is the trimaran. This research conducted a CFD analysis of resistance for trimaran hull forms as a parameter range of practical hull forms is established round bilge trimaran hull forms based on the NPL systematic series and Axe-Bow Modification at the main hull. The resistances of trimaran hull forms are, therefore, estimated by using ANSYS CFX, a commercial CFD software package. Trimaran model was analysed on variation of main hull and side independently, S/L = 0.3 and S/L = 0.4 at Fr = 0.15, 0.2, 0.25, 0.3, 0.4 and 0.5. The results showed that the trimaran ship with the Axe-Bow modification showed better results when compared to the NPL Hull, with an average value of 26.6%. This shows a positive influence with the use of Axe-Bow on the modification of the NPL Hull in the trimaran ship configuration.