Development of an Alternative to the E9 Procedure for Predicting Boundary-Layer Transition.

Abstract

A method has been devised which can be used in conjunction with linear-stability theory for predicting boundary-layer transition. As with the classical 'eq' procedure, for a given frequency the growth of a disturbance is computed downstream of the initial point of instability using the linearized equations of motion. In contrast to the 'eq' procedure in which the linearized equations are used all the way to the inferred transition point, an approximate set of long-time averaged equations which account for nonlinearity is used to describe the ultimate nonlinear growth of the disturbance. Because the new method accounts for nonlinear processes it holds promise as a more physically sound procedure than the eq method for determining the point at which a boundary layer undergoes transition to turbulence. (Author)

Open PDF

Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1979
Accession Number
ADA074071

Entities

People

  • David C. Wilcox

Tags

Communities of Interest

  • Air Platforms
  • Ground and Sea Platforms
  • Materials and Manufacturing Processes
  • Weapons Technologies

DTIC Thesaurus Topics

  • Boundaries
  • Boundary Layer
  • Boundary Layer Transition
  • Coefficients
  • Computational Fluid Dynamics
  • Engineering
  • Equations
  • Equations Of Motion
  • Jet Propulsion
  • Mechanical Engineering
  • Mechanics
  • Military Research
  • Pressure Gradients
  • Reynolds Number
  • Transitions
  • Turbulence
  • Turbulent Mixing

Fields of Study

  • Physics

Readers

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

Technology Areas

  • AI & ML
  • AI & ML - Bayesian Inference
  • AI & ML - Machine Learning Algorithms