Numerical study of resistance and form factor of high-speed catamarans

Abstract

Since the prediction of resistance of the full-scale ship mainly relies on extrapolation of form factor of the model, it is important to determine the form factor precisely. Nowadays, the computer performance has been developed, commercial CFD code with Reynolds-averaged Navier-Stokes Equations (RANS), which is widely accepted and used by many researchers is capable of determining resistance components. This paper presents the development and procedures for the prediction resistance components and form factor of displacement catamarans by using commercial CFD code, STAR CCM+, with SST k-ω turbulence model. The Wigley catamarans with three hull configurations including S/L = 0.2, 0.3 and 0.4 are investigated at Froude number between 0.2 and 0.8. Resistance components, which are total (CT), skin friction (CF), viscous (CV), residual (CR) and wave (CW) resistance, form factor (1+k), form resistance interference factor (β), wave resistance interference factor (τ) and wave elevation along the hull are estimated and validated against experiment retrieved from Insel (1992). The results show that CFD code with RANS equations is capable of estimating resistance components and demonstrates that form factor increases with speed (Fn).