Turbulence and secondary motions in square duct flow
نویسندگان
چکیده
منابع مشابه
Characterisation of Marginally Turbulent Square Duct Flow
We have performed direct numerical simulation of fully developed turbulent flow in a straight duct with square cross-section. The main objective of the present study is to determine the minimal requirements for maintaining turbulence in duct flows [1]. A detailed analysis of this limit regime allows to elucidate the dominant mechanisms governing the marginally turbulent state, where the self-su...
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The spatial growth of small perturbations developing on a fully developed base flow in a duct with two inhomogeneous cross-flow directions is examined. For a laminar mean flow it is shown that optimally configured vortices at an upstream cross-section induce large transient amplification of a disturbance energy norm downstream. Such a linear growth is a likely initial stage of transition in duc...
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In this paper, several low and high Reynolds number versions of k-ε and Reynolds stress turbulence models have been evaluated in a channel and a square duct flow with and without a magnetic field by comparing the predictions with direct numerical simulations data. The simulations are performed using FLUENT solver. The additional source terms for magnetic field effects on turbulence have been in...
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ژورنال
عنوان ژورنال: Journal of Fluid Mechanics
سال: 2018
ISSN: 0022-1120,1469-7645
DOI: 10.1017/jfm.2018.66