FLOW OVER AIRFOILS IN THE TRANSONIC REGIME-PREDICTION OF BUFFET ONSET.

Abstract

The report is concerned with the calculations of the viscous supercritical flow over planar airfoils, and in particular with the prediction of buffet onset using as a criterion the pressure divergence at the trailing edge. To determine the above flow an iterative procedure is considered in which the initial approximation is obtained by quasi-decoupling the boundary layer flow from the outer inviscid flow. The steady inviscid flow is then calculated by an unsteady finite difference method, in which the desired steady flow is obtained as the asymptotic flow at large times. The inviscid procedure is then applied to two examples with satisfactory results. For the treatment of the boundary layer, the initial laminar portion, and the transition zone are calculated in a conventional way, and an integral procedure based upon the continuity and streamwise momentum equations is suggested for the turbulent portion, containing the shock-induced separation, and for the wake, in which specific empirical input is required. (Author)

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1970
Accession Number
AD0709377

Entities

People

  • Hideo Yoshihara
  • Richard Magnus

Organizations

  • General Dynamics

Tags

DTIC Thesaurus Topics

  • Boundaries
  • Boundary Layer
  • Boundary Layer Flow
  • Decoupling
  • Flow
  • Inviscid Flow
  • Layers
  • Steady Flow
  • Supercritical Flow
  • Trailing Edges

Fields of Study

  • Physics

Readers

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