Numerical analysis of three-dimensional turbulent flow around ship like bodies using finite-volume method

Abstract

This research work deals with numerical simulations of turbulent flow around ship like bodies. The Reynolds -averaged Navier-Stokes equations for three-dimensional flow are discretized by finite volume method in block-structured collocated body fitted non-orthogonal grids and solved with SIMPLE algorithm. The k-ε turbulence model and standard wall function are adopted. Both necessary coordinate and velocity transformations are given by tensor calculus. Rhie and Chow interpolation is used to get a good coupling between pressure and velocity. The linear equations obtained by Picard type linearization are solved within the inner iteration loops, by incomplete LU decomposition method by Stone. Numerical analysis of turbulent flow around NACA 0012 and NACA 4412 hydrofoils is carried out to determine the surface pressure distribution and lift forces for different angles of attack. To study the uncertainty analysis of solution, a systematic variation of number of control volumes of C-type structured mesh is performed for NACA 0012 and NACA 4412 hydrofoils. The pressure distributions and wave making resistances at various speeds of the Wigley hull, Series 60 hull and S175 container ship hull are also computed to further substantiate the validity of the numerical methodology. The computational results are presented in a non-dimensional form. The obtained results are compared with experimental and established theoretical data. The obtained lift coefficients of NACA 0012 and 4412 are compared to the experimental result. The obtained lift coefficients show small discrepancy at lower angle of attack but discrepancy is more notable at higher angle of attack. The results obtained for wave making resistance of Wigley hull and Series 60 hull form are compared to the experimental result and established numerical result. The obtained wave making resistances for Wigley hull and Series 60 hull show small deviations at relatively small Froude numbers but deviations are large at relatively high Froude numbers. However, lack of experimental data makes it difficult to validate the resistance computed for S175 container ship hull.