Unsteady RANS method for surface ship boundary layer and wake and wave field

Results are reported of an unsteady Reynolds-averaged Navier–Stokes (RANS) method for simulation of the boundary layer and wake and wave field for a surface ship advancing in regular head waves, but restrained from body motions. Second-order finite differences are used for both spatial and temporal discretization and a Poisson equation projection method is used for velocity–pressure coupling. The exact kinematic free-surface boundary condition is solved for the free-surface elevation using a body-fitted/free-surface conforming grid updated in each time step. The simulations are for the model problem of a Wigley hull advancing in calm water and in regular head waves. Verification and validation procedures are followed, which include careful consideration of both simulation and experimental uncertainties. The steady flow results are comparable to other steady RANS methods in predicting resistance, boundary layer and wake, and free-surface effects. The unsteady flow results cover a wide range of Froude number, wavelength, and amplitude for which first harmonic amplitude and phase force and moment experimental data are available for validation along with frequency domain, linear potential flow results for comparisons. The present results, which include the effects of turbulent flow and non-linear interactions, are in good agreement with the data and overall show better capability than the potential flow results. The physics of the unsteady boundary layer and wake and wave field response are explained with regard to frequency of encounter and seakeeping theory. The results of the present study suggest applicability for additional complexities such as practical ship geometry, ship motion, and maneuvering in arbitrary ambient waves. Copyright © 2001 John Wiley & Sons, Ltd.

[1]  P. E. Guillerm,et al.  Three-Dimensional Free Surface Viscous Flow around a Ship In Forced Motion , 1999 .

[2]  Lafayette K. Taylor,et al.  Computation of steady and unsteady flows with a free surface around the Wigley hull , 1998 .

[3]  Hideaki Miyata,et al.  CFD simulation of 3-dimensional motion of a ship in waves: application to an advancing ship in regular heading waves , 2000 .

[4]  D. Drikakis,et al.  An implicit unfactored method for unsteady turbulent compressible flows with moving boundaries , 1999 .

[5]  Frederick Stern,et al.  Computation of Unsteady Viscous Marine-Propulsor Blade Flows—Part 1: Validation and Analysis , 1997 .

[6]  F. Stern,et al.  Stokes Layers in Horizontal-Wave Outer Flows , 1996 .

[7]  J Longo,et al.  Technical Note: Evaluation of Surface-Ship Resistance and Propulsion Model-Scale Database for CFD Validation , 1996 .

[8]  C. W. Hirt,et al.  Volume of fluid (VOF) method for the dynamics of free boundaries , 1981 .

[9]  P. Ott,et al.  Computation of Unsteady 3-D Transonic Flows Due to Fluctuating Back-Pressure Using k-ε Turbulence Closure , 1996 .

[10]  S. Damelin,et al.  Laminar boundary layers subjected to high-frequency traveling-wave fluctuations , 1993 .

[11]  Frederick Stern,et al.  A Large-Domain Approach for Calculating Ship Boundary Layers and Wakes and Wave Fields for Nonzero Froude Number , 1996 .

[12]  Emmanuel Guilmineau,et al.  Numerical Study of Dynamic Stall on Several Airfoil Sections , 1999 .

[13]  Frederick Stern,et al.  An interactive approach for calculating ship boundary layers and wakes for nonzero Froude number , 1992 .

[14]  Johan M.J. Journee,et al.  Experiments and calculations on Four Wigley Hullforms , 1992 .

[15]  John A. Ekaterinaris,et al.  Computation of oscillating airfoil flows with one- and two-equation turbulence models , 1994 .

[16]  Stephen Michael Scorpio Fully Nonlinear Ship-Wave Computations Using a Multipole Accelerated, Desingularized Method , 1997 .

[17]  Rainald Loehner,et al.  An unstructured grid-based, parallel free surface solver , 1997 .

[18]  Masataka Fujino,et al.  A study on flow field around full ship forms in maneuvering motion , 1998 .

[19]  Antony Jameson,et al.  Fast multigrid method for solving incompressible hydrodynamic problems with free surfaces , 1993 .

[20]  Shanhong Ji,et al.  Flutter Computation of Turbomachinery Cascades Using a Parallel Unsteady Navier-Stokes Code , 1999 .

[21]  Roger L. Simpson,et al.  Turbulence model for steady and unsteady boundary layers in strong pressure gradients , 1997 .

[22]  Lafayette K. Taylor,et al.  A time accurate calculation procedure for flows with a free surface using a modified artificial compressibility formulation , 1994 .

[23]  Hugh W. Coleman,et al.  Uncertainties and CFD Code Validation , 1997 .

[24]  Fotis Sotiropoulos,et al.  A primitive variable method for the solution of three-dimensional incompressible viscous flows , 1992 .

[25]  F. Harlow,et al.  Numerical Calculation of Time‐Dependent Viscous Incompressible Flow of Fluid with Free Surface , 1965 .

[26]  P. Ott,et al.  Computation of unsteady three-dimensional transonic nozzle flows using k-epsilon turbulence closure , 1996 .

[27]  Dick K. P. Yue,et al.  A high-order spectral method for the study of nonlinear gravity waves , 1987, Journal of Fluid Mechanics.

[28]  Philippe Reynier,et al.  Numerical prediction of unsteady compressible turbulent coaxial jets , 1998 .

[29]  John A. Ekaterinaris,et al.  Evaluation of turbulence models for unsteady flows of an oscillating airfoil , 1995 .

[30]  Hugh W. Coleman,et al.  VERIFICATION AND VALIDATION OF CFD SIMULATIONS , 1999 .

[31]  Takuya Ohmori,et al.  Finite-volume simulation of flows about a ship in maneuvering motion , 1998 .

[32]  Ken Badcock,et al.  Simulation of unsteady turbulent flows around moving aerofoils using the pseudo-time method , 2000 .

[33]  Juan J. Alonso,et al.  Efficient Computation of Unsteady Viscous Flows by an Implicit Preconditioned Multigrid Method , 1998 .

[34]  Justin H McCarthy COLLECTED EXPERIMENTAL RESISTANCE COMPONENT AND FLOW DATA FOR THREE SURFACE SHIP MODEL HULLS , 1985 .