Vortical and turbulent structures for KVLCC2 at drift angle 0, 12, and 30 degrees

Abstract Detached Eddy Simulation on a 13 M grid is conducted for a KVLCC2 tanker hull form at drift angle 30°. The objective is to identify and analyze the vortical structures, instabilities, and turbulent structures with analogy to the vortex breakdown and helical instability analysis for delta wing at large angles of attack. One shear layer, one Karman-like vortex shedding, and three helical mode instabilities are identified. The after-body side vortex, fore-body side vortex, and after-body bilge vortex exhibit all characteristics for vortex breakdown. For helical instability in the wake of the vortex breakdowns, Strouhal number using the ship length or the distance along vortex core shows the same trend with delta wings. The turbulent kinetic energy peaks near the separation point at the bow and on the vortex core of all vortices. For the after-body side vortex, turbulent kinetic energy reaches local maximum right after the vortex breakdown and is intensified along the vortex core further downstream. The simulations at drift angle 0° show four unsteady aft-body vortices, significantly improve the prediction of integral variables and local flows. In addition to the three steady vortices identified before, the simulations at drift angle 12° show unsteady aft-body hairpin and after-body side vortices.

[1]  Ismet Gursul,et al.  Unsteady nature of leading edge vortices , 1997 .

[2]  Ralph Noack,et al.  SUGGAR: A General Capability for Moving Body Overset Grid Assembly , 2005 .

[3]  P. Moin,et al.  Eddies, streams, and convergence zones in turbulent flows , 1988 .

[4]  Christer Fureby,et al.  Towards the use of large eddy simulation in engineering , 2008 .

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

[6]  Serhat Hosder,et al.  Unsteady Turbulent Skin Friction and Separation Location Measurements on a Maneuvering Undersea Vehicle , 2001 .

[7]  Frederick Stern,et al.  Unsteady free surface wave-induced separation: Vortical structures and instabilities , 2009 .

[8]  D. H. Kim,et al.  Measurement of flows around modern commercial ship models , 2001 .

[9]  Frederick Stern,et al.  Comparison of CFD and EFD for the Series 60 CB= 0.6 in steady drift motion , 2002 .

[10]  Frederick Stern,et al.  Closure to "Discussion of 'Factors of Safety for Richardson Extrapolation'" (2011, ASME J. Fluids Eng., 133, p. 115501) , 2011 .

[11]  Frederick Stern,et al.  Effects of drift angle on model ship flow , 2002 .

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

[13]  Frederick Stern,et al.  Unsteady free-surface wave-induced separation: analysis of turbulent structures using detached eddy simulation and single-phase level set , 2007 .

[14]  P. Moin,et al.  Direct numerical simulation of turbulent flow over a backward-facing step , 1997, Journal of Fluid Mechanics.

[15]  C. Fureby.  Large Eddy Simulation of Ship Hydrodynamics , 2008 .

[16]  Lars Larsson,et al.  CFD in Ship Hydrodynamics - Results of the Gothenburg 2010 Workshop , 2011 .

[17]  Hugh W. Coleman,et al.  Comprehensive Approach to Verification and Validation of CFD Simulations—Part 2: Application for Rans Simulation of a Cargo/Container Ship , 2001 .

[18]  Miguel R. Visbal,et al.  Unsteady aerodynamics of nonslender delta wings , 2005 .

[19]  Scott A. Morton,et al.  Detached-Eddy Simulations and Reynolds-Averaged Navier-Stokes Simulations of Delta Wing Vortical Flowfields , 2002 .

[20]  T. Xing,et al.  Factors of Safety for Richardson Extrapolation , 2010 .

[21]  Yasuyuki Toda,et al.  MEAN-FLOW MEASUREMENTS IN THE BOUNDARY LAYER AND WAKE AND WAVE FIELD OF A SERIES 60 CB=0.6 SHIP MODEL - PART 1: FROUDE NUMBERS 0.16 AND 0.316 , 1992 .

[22]  Philippe R. Spalart,et al.  Detached-Eddy Simulations Over a Simplified Landing Gear , 2002 .

[23]  Frederick Stern,et al.  Scalability studies and large grid computations for surface combatant using CFDShip-Iowa , 2011, Int. J. High Perform. Comput. Appl..

[24]  Frederick Stern,et al.  Unsteady RANS simulation of the ship forward speed diffraction problem , 2006 .

[25]  Frederick Stern,et al.  URANS and DES analysis for a Wigley hull at extreme drift angles , 2010 .

[26]  M A Abkowitz,et al.  LECTURES ON SHIP HYDRODYNAMICS--STEERING AND MANOEUVRABILITY , 1964 .

[27]  Frederick Stern,et al.  URANS simulations of static and dynamic maneuvering for surface combatant: part 2. Analysis and validation for local flow characteristics , 2012 .

[28]  A. Gosman,et al.  Solution of the implicitly discretised reacting flow equations by operator-splitting , 1986 .

[29]  Munehiko Hinatsu,et al.  Measurements of hydrodynamic forces, surface pressure, and wake for obliquely towed tanker model and uncertainty analysis for CFD validation , 2006 .

[30]  Jun Shao,et al.  Quantitative V&V of CFD simulations and certification of CFD codes , 2006 .

[31]  Frederick Stern,et al.  Urans and des simulations of static and dynamic maneuvering for surface combatant , 2009 .

[32]  David A. Boger,et al.  Improvements to SUGGAR and DiRTlib for Overset Store Separation Simulations , 2009 .

[33]  Ismet Gursul,et al.  Unsteady flow phenomena over delta wings at high angle of attack , 1994 .

[34]  Frederick Stern,et al.  Flow pattern around an appended tanker hull form in simple maneuvering conditions , 2005 .

[35]  Frederick Stern,et al.  Verification and validation of RANS maneuvering simulation of Esso Osaka: effects of drift and rudder angle on forces and moments , 2003 .

[36]  D. Degani,et al.  Graphical visualization of vortical flows by means of helicity , 1990 .

[37]  Ismet Gursul,et al.  Review of Unsteady Vortex Flows over Slender Delta Wings , 2005 .

[38]  Frederick Stern,et al.  Evaluation of linear and nonlinear convection schemes on multidimensional non‐orthogonal grids with applications to KVLCC2 tanker , 2009 .

[39]  Hyung Jin Sung,et al.  Large-eddy simulation of turbulent mixed convection in a vertical annulus with a rotating inner cylinder , 2006 .

[40]  L. Sigurdson.  The structure and control of a turbulent reattaching flow , 1995, Journal of Fluid Mechanics.

[41]  P. Spalart,et al.  Physical and Numerical Upgrades in the Detached-Eddy Simulation of Complex Turbulent Flows , 2002 .

[42]  Riccardo Broglia,et al.  Experience from SIMMAN 2008—The First Workshop on Verification and Validation of Ship Maneuvering Simulation Methods , 2011 .

[43]  Suak-Ho Van,et al.  Wind tunnel tests on flow characteristics of the KRISO 3,600 TEU containership and 300K VLCC double-deck ship models , 2003 .

[44]  Volker Bertram,et al.  Benchmarking of computational fluid dynamics for ship flows: the Gothenburg 2000 workshop , 2003 .

[45]  Philippe R. Spalart,et al.  Detached-eddy simulation of an airfoil at high angle of attack , 1999 .

[46]  Russell M. Cummings,et al.  Aerodynamic Analysis of a Generic Fighter Using Delayed Detached-Eddy Simulation , 2009 .

[47]  Frederick Stern,et al.  An unsteady single‐phase level set method for viscous free surface flows , 2007 .