On the Parabolized Navier-Stokes Equations without Sublayer Assumptions

Abstract

A new implicit, iteractive method of solving the Parabolized Navier- Stokes (PNS) Equations claims to overcome the elliptic character of the embedded subsonic sublayer by explicitly introducing pressure as an additional state variable. The Bhutta-Lewis approach makes no sublayer pressure assumptions. The validity and basis of that method is explored in this thesis by examining the relevant eigenvalues governing marching stability. An original code was also developed in order to examine the numerical character of the marching, iterative solutions as they develop. Test cases were carried out for a two dimensional wedge configuration at Mach numbers 3 and 15 and Reynolds numbers ranging from 4000 to 10 million at the initial data plane. An eigenvalue analysis disclosed that the method is unstable in subsonic regions. Results for the test cases confirmed the presence of instability. Classic departure behavior was produced in tightly clustered grids and convergence to separated flow was shown in less clustered grids. Marching was achieved only in relatively high Reynolds number flow with a large stable marching step size. (Theses)

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1987
Accession Number
ADA186127

Entities

People

  • Stephen C. Pluntze

Organizations

  • Air Force Institute of Technology

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Force
  • Boundary Layer
  • Computational Fluid Dynamics
  • Computational Science
  • Coordinate Systems
  • Differential Equations
  • Eigenvalues
  • Equations
  • Equations Of State
  • Fluid Dynamics
  • Geometry
  • Mach Number
  • Navier Stokes Equations
  • Pressure Distribution
  • Reynolds Number
  • Three Dimensional
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Fluid Mechanics and Fluid Dynamics.
  • Theoretical Analysis.