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Turbulent mixing layer from two non-parallel streams

Published online by Cambridge University Press:  04 July 2016

M. A. Azim
Affiliation:
Department of Mechanical Engineering, Bangladesh University of Engineering & Technology, Dhaka, Bangladesh
A. K. M. S. Islam
Affiliation:
Department of Mechanical Engineering, Bangladesh University of Engineering & Technology, Dhaka, Bangladesh

Abstract

An experimental investigation has been conducted on the mixing layers produced from the merging of two non-parallel streams. To study the effect of velocity ratio on its development, mixing layers were produced with velocity ratios 0·7, 0·8 and 0·9. The boundary layers were untripped and initially turbulent in all the cases. For each velocity ratio, measurements were made at six streamwise locations. It was found that for velocity ratios 0·7 and 0·8, mixing layers appear to attain self-similarity but failed for 0·9 within the measurement domain. The development distance of the mixing layer flow was increased with increasing velocity ratio and the splitter wake was found to play an important role in its development. The mixing layer growth was found to decrease with increasing velocity ratio though the spread of the layer was larger at the high speed side.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2003 

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