Evaluation of an URANS-LES Hybrid Approach for Turbulent Free Surface Flows Around Surface-Piercing Bodies

Abstract

A hybrid turbulence modeling approach combining unsteady Reynolds-averaged Navier-Stokes (URANS) equation-based modeling and large eddy simulation (LES) is applied to turbulent free-surface flows around surface-piercing bodies involving wave-breaking and bubble formation. Based on a two-equation kappa-epsilon turbulence model, the hybrid model reduces to a RANS turbulence model or a subgrid-scale turbulence model depending on the local mesh resolution (filter size) and the local integral turbulence length-scale. The computations were carried out using a second-order-accurate finite-volume Navier-Stokes solver that permits use of arbitrary unstructured meshes and local mesh refinement. Volume-of-fluid (VOF) method was employed to capture the free-surface. The URANS-LES hybrid approach is shown to reproduce the salient features of the turbulent free-surface flows around the surface-piercing bodies with reasonable accuracy on relatively coarse meshes on which the fidelity of LES degrades.

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Document Details

Document Type
Technical Report
Publication Date
Oct 01, 2007
Accession Number
ADP023899

Entities

People

  • Davor Cokljat
  • Sung-eun Kim

Organizations

  • Naval Surface Warfare Center Carderock Division

Tags

Communities of Interest

  • Energy and Power Technologies
  • Ground and Sea Platforms
  • Space

DTIC Thesaurus Topics

  • Accuracy
  • Aerodynamic Characteristics
  • Aeroelasticity
  • Boundary Layer
  • Computational Fluid Dynamics
  • Equations
  • Fluid Dynamics
  • Fluid Flow
  • Frequency
  • Froude Number
  • Hydrodynamics
  • Large Eddy Simulation
  • Mechanical Properties
  • Physical Properties
  • Static Pressure
  • Surface Waves
  • Test And Evaluation

Fields of Study

  • Physics

Readers

  • Computational Fluid Dynamics (CFD)