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Reynolds stress: Difference between revisions
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:<math>R_{xy} = \left \langle \tilde{u}_x \tilde{u}_y \right \rangle</math> | :<math>R_{xy} = \left \langle \tilde{u}_x \tilde{u}_y \right \rangle</math> | ||
Thus, a non-zero value of the gradient of the Reynolds stress (of fluctuating flow components) can drive a laminar flow. Obviously, <math>\tilde{u}_x</math> and <math>\tilde{u}_y</math> must be ''correlated'' for this to work | Thus, a non-zero value of the gradient of the Reynolds stress (of fluctuating flow components) can drive a laminar flow. Obviously, <math>\tilde{u}_x</math> and <math>\tilde{u}_y</math> must be ''correlated'' for this to work. | ||
This correlation occurs naturally in the presence of a background (mean) gradient driving turbulent transport. | |||
Once the laminar flow shear develops, it may suppress small-scale turbulence, leading to a reduction of transport. | |||
<ref>[http://link.aps.org/doi/10.1103/RevModPhys.72.109 P. W. Terry, ''Suppression of turbulence and transport by sheared flow'', Rev. Mod. Phys. '''72''' (2000) 109–165]</ref> | |||
== See also == | == See also == | ||