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The effect of skewing on the vorticity produced by an airjet vortex generator

Published online by Cambridge University Press:  04 July 2016

A. A. Barberopoulos  and
K. P. Garry
A. A. Barberopoulos
Affiliation:
Flow Control and Prediction GroupCollege of AeronauticsCranfield University Bedfordshire, UK
K. P. Garry
Affiliation:
Flow Control and Prediction GroupCollege of AeronauticsCranfield University Bedfordshire, UK
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Abstract

The vorticity production by a single vortex generator jet in a turbulent boundary layer at high speed and zero pressure gradient was studied by analysing surface-flow patterns. The investigation involved a range of jet mass flow rates and skew angles while the freestream Mach number and jet pitch angle were held constant. A qualitative analysis of the skin friction patterns demonstrated the effective role of the skew angle as a bifurcation parameter. The vortex production is classified into three main regimes as the skew angle increases from zero (fully downstream) to 180° (fully upstream). Better understanding of the physical mechanism behind the transition from the first regime to the second is crucial in the design of the airjet vortex generator.

Type
Research Article
Information
The Aeronautical Journal , Volume 102 , Issue 1013 , March 1998 , pp. 171 - 177
Copyright
Copyright © Royal Aeronautical Society 1998 

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