NUMERICAL ANALYSIS OF A REATTACHED FLOW BEHIND A RIB
https://doi.org/10.29235/1561-8323-2018-62-1-109-114
Abstract
Turbulent characteristics of a reattached flow separated from a rib in an air flat channel were numerically analyzed by RANS and LES methods. The both methods showed low pressure regions in corners formed by the rib and the channel walls that caused a vorticity tube to be formed along the rib. Nevertheless in RANS, a reattached flow was identified as two-dimensional with a velocity decreasing near the channel bottom wall. In LES, the low pressure regions caused transverse and normal motions in the separation region that resulted in redistributions between velocity components, Reynolds stresses and the velocity decrease near the channel bottom wall, i.e., the formation of three-dimensional reattached flow.
About the Authors
Tatiana A. BaranovaBelarus
Researcher
15, P. Brovka Str., Minsk
Valery L. Zhdanov
Belarus
D. Sc. (Engineering), Leading researcher
15, P. Brovka Str., Minsk
Dmitrii A. Ivanov
Belarus
Ph. D. (Physics and Mathematics), Senior researcher
15, P. Brovka Str., Minsk
Yaroslav I. Smulskii
Russian Federation
Leading specialist
2, Lavrentiev Ave., 630090, Novosibirsk
Viktor I. Terekhov
Russian Federation
D. Sc. (Engineering), Professor, Head of the Department
2, Lavrentiev Ave., 630090, Novosibirsk
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