Date of Award

Spring 1993

Document Type

Thesis

Department

Mechanical & Aerospace Engineering

Program/Concentration

Mechanical Engineering

Committee Director

Robert L. Ash

Committee Member

John M. Kuhlman

Committee Member

J. Mark Dorrepaal

Call Number for Print

Special Collections; LD4331.E56L55

Abstract

A mathematical model has been developed to simulate the events which occur at the interface between a turbulent boundary layer and the irrotational free stream. By assuming the streamwise velocity component of this interface to be constant and that the interface is uncontorted initially, the solution to the equations of motion is used to derive the position functions of a point element on the interface. This analysis is restricted to a fully developed incompressible turbulent boundary layer with zero pressure gradient. Vertical velocity disturbances which are periodic in the spanwise direction and restricted to small streamwise domains are assumed.

The model predicts pairs of upward bulging and downward jetting events. The size of these events shows that this model may represent the typical eddies which have been described by other investigators. The wall-ward jetting indicates the occasional engulfment of inviscid flow into the turbulent boundary layer. It also predicts that the superlayer can account for only about 10 percent of the required kinetic energy supply. The bulging event shows that the growth of the turbulent boundary layer thickness is not created entirely by the small scale motions.

Rights

In Copyright. URI: http://rightsstatements.org/vocab/InC/1.0/ This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).

DOI

10.25777/ce8n-5y64

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