RANSE with free surface computations around fixed DTMB 5415 model and other Baliño?s fishing vessels

Abstract

One important issue in the CFD application is the prediction of the power demand of a new ship. For this purpose the interaction between the hull, rudder and the propeller must be correctly accounted for. This paper presents results of the computations performed in the ETSIN for different ships with the RANSE free surface commercial solver CFX. Some of the computational results are validated against experimental data in terms of various global and local quantities. The CFX code is based on a finite volume discretization. The turbulence model used in the calculations was the SST (Shear Stress Transport) model, and the volume of fluid method is used to model the free-surface flow. The numerical schemes use higher order cells to satisfy the momentum, pressure and turbulence quantities where each hexahedral cell is further subdivided into eight sub-volumes. A control volume is formed from the sub-volumes surrounding a grid node and a first order finite element basis function is used for each subvolume. The momentum and pressure are simultaneously satisfied using a coupled solution system. All the numerical equations are solved using algebraic multi-grid acceleration with implicit smoothing. Parallel computation on a 2 processors PC was adopted to reduce the required computational time.