| During the last two decades, a great deal of efforts has been devoted toward developing numerical tools with the help of CFD technique, which is capable of predicting ship hydrodynamic performance. With the development of numerical methods and enhancement of calculating ability of Ship CFD, a great successive progress has been made in the prediction precision which makes Ship CFD play an important role on facilitating ship's optimum design. In this regard, it tends to be an alternative of towing tank. Especially, the numerical solution of three dimensional viscous flows around ship hull has met with success in capturing the features of the flow field including that in the stern region which is difficult to model test and is significant for accurate prediction of total resistance and screw propeller design for full scale ship.Based on the analysis of the routine numerical methods for viscous flow, the method for solving steady Reynolds-Averaged Navier-Stokes (RANS) equation is applied for solving the high Reynolds number turbulence problem. In order to enclose the equation system, the standard turbulence model with wall function is selected to calculate turbulent viscosity and turbulent kinetic energy. After analyzing the difficulties in solving viscous incompressible flow and comparing all kinds of usual pressure-speed coupling algorithms, the pseudo-compressibility method is adopted. Furthermore, the non-dimensional strategy is utilized to improve the numerical adaptability of the solver.Common boundary conditions, especially the inlet and wall conditions of ship viscous flows, are analyzed and corresponding measures of giving inlet values and satisfying wall condition are presented.To implement numerical solution of RANS equations, a collocated grid for pressure-speed is used. Based on Finite Volume Method, an approximation of blending central differencing scheme and upwind differencing scheme is introduced into calculation of the convection flux, whereas an approximation of central differencing scheme for diffusion flux and locally implicit discretisationidea strengthening the main-diagonal of the coefficient matrix for source term are adopted. In addition, geometry elements are calculated in local coordinate system and RANS equation discretisation is expressed in Cartesian coordinate system.To satisfy numerical boundary conditions, several simplicities are made. Moreover, to overcome the disadvantages of pseudo-compressibility algorithm, adaptable artificial dissipation is taken into account.High quality grid, which is an important part of Ship CFD, has a large effect on accuracy and rapidity of the convergence of the equation systems' iteration. The grid generation technique by means of solving elliptic partial differential equation is used to generate structured grid. In addition, discretisation, solution and especially the control function of Poisson Equation are discussed in details. As a need of practice, distribution of nodes on the boundary and boundary mapping from physical domains to computational domains are discussed. Furthermore, multi-block technique and its application steps are discussed. On the basis of all these researches, a simple mesh generator is designed and validated by generating two dimensional and three dimensional structured grids.The solution algorithms of algebraic equation systems are discussed, and SIP iteration method with high ability is selected for iteration solution of the equation systems obtained by RANS equation discretisation. To improve the stability of solution procedure, the pretreatment by the successive under-relaxation is applied to modify the equations' coefficients. The convergence condition is specified as criterion of converged iteration of equation systems. To solve complicated flow fields, a blocks-coupling algorithm is implemented for multi-block grids. Correspondingly, a solver is developed for the solution procedure.To validate the proposed solution algorithm and test the performance of the developed solver, several cases of low-...
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