An Incompressible 3-D Navier-Stokes Method with Adaptive Hybrid Grids.

Abstract

A numerical method has been developed for the unsteady Navier-Stokes equations of incompressible flow in three dimensions. The momentum equations, combined with a pressure correction equation, are solved employing a non-staggered grid which results in a simpler formulation compared to the classical approach of using staggered meshes. The momentum equations are solved explicitly using a finite volume algorithm, while the pressure Poisson equation is discretized using the Galerkin finite element method and implicitly solved. The grid is formed with hybrid (prismatic/tetrahedral) elements. Equation adaptation is utilized, the Navier-Stokes equations are solved in the prismatic region, which includes the viscous region, and the Euler equations are solved in the tetrahedral region, which is inviscid. Adaptive local grid refinement of the prism and tetrahedral cells is employed in order to optimize the mesh to the flow solution. Validation of the algorithm is performed using experimental and other numerical data, and demonstrate the accuracy and robustness of the unsteady three-dimensional method. An additioual study is conducted using an existing two-dimensional incompressible Navier-Stokes solver. The two-dimensional solver is applied to predict the hydrodynamic forces on a circular cylinder due to reversing flows.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Sep 22, 1995
Accession Number
ADA299979

Entities

People

  • Alice J. Chen

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Force
  • Boundary Layer
  • Computational Fluid Dynamics
  • Computational Science
  • Differential Equations
  • Euler Equations
  • Fluid Dynamics
  • Fluid Flow
  • Fluid Mechanics
  • Geometry
  • Hydrodynamics
  • Mechanical Properties
  • Navier Stokes Equations
  • Steady Flow
  • Three Dimensional
  • Two Dimensional
  • Viscous Flow

Fields of Study

  • Physics

Readers

  • Computational Fluid Dynamics (CFD)
  • Fluid Mechanics and Fluid Dynamics.