Method for Computing Three Dimensional Unsteady Flows by Solution of the Vorticity Equation on a Lagrangian Mesh

Abstract

A method for computing three dimensional unsteady flows about an object. An allowable error is established for the vorticity term calculations, and object geometry is provided giving surface points on an object and a region of interest. A mesh is established incorporating points on the object. Initial flow conditions are set at the surface. Vorticity values that will satisfy boundary conditions are set at the provided surface points. A new mesh is established incorporating the provided points and other points in the region of interest. Boxes are generated containing the provided points and other points. Velocities and pressures at each point are calculated from the flow conditions, vorticity values and boundary conditions. A time variable is incremented and each point is moved by applying the calculated velocity. Vorticity at each point is then recalculated. The method is iterated starting with the step of satisfying boundary conditions until the incremented time variable exceeds a predetermined value.

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Document Details

Document Type
Technical Report
Publication Date
Sep 29, 2000
Accession Number
ADD019910

Entities

People

  • James S. Uhlman
  • John R. Grant
  • Stephen A. Huyer

Organizations

  • United States Department of the Navy

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Algorithms
  • Boundaries
  • Boundary Layer
  • Central Processing Units
  • Computational Fluid Dynamics
  • Computational Science
  • Diffusion
  • Equations
  • Flow
  • Fluid Flow
  • Geometry
  • Inventions
  • Layers
  • Least Squares Method
  • Pressure Distribution
  • Three Dimensional
  • Unsteady Flow

Fields of Study

  • Physics

Readers

  • Aerodynamics.
  • Calculus or Mathematical Analysis
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)