Unsteady Three-Dimensional Euler Equations Solutions on Dynamic Blocked Grids.

Abstract

An unsteady implicit Euler equation solution algorithm using finite volume discretization and flux-vector splitting is presented. The effect on time-accuracy of different time step sizes, different approximate factorizations, and formal first-order versus second-order time accuracy is determined by numerical experimentation on a NACA0012 airfoil undergoing pitch oscillations in transonic flow. It is shown that time step sizes corresponding to Courant numbers of 100 or more can produce time-accurate results if flow variable s are not rapidly changing. Due to better stability properties, the two-factor method gives better results than the six-factor method. Also, the second-order-time-accurate three point backward time discretization is shown to yield only slight improvement over the first-order-time-accurate backward Euler time discretization. Methods of obtaining time-accurate Euler solutions on blocked grids are analyzed and verified by comparing multi-block solutions with equivalent one-block solutions.

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Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1986
Accession Number
ADA173977

Entities

People

  • Dave M. Belk

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Force
  • Aircrafts
  • Boundary Layer
  • Computational Fluid Dynamics
  • Computational Science
  • Differential Equations
  • Equations
  • Euler Equations
  • Flow
  • Fluid Dynamics
  • Fluid Flow
  • Navier Stokes Equations
  • Pressure Distribution
  • Three Dimensional
  • Transonic Flow
  • Two Dimensional
  • Unsteady Aerodynamics

Fields of Study

  • Physics

Readers

  • Computational Fluid Dynamics (CFD)
  • Mathematical Modeling and Probability Theory.
  • Regression Analysis.