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arXiv · 1104.4526

Heat transport by laminar boundary layer flow with polymers

Roberto Benzi·Emily S. C. Ching.·Vivien W. S. Chu
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Abstract

Motivated by recent experimental observations, we consider a steady-state Prandtl-Blasius boundary layer flow with polymers above a slightly heated horizontal plate and study how the heat transport might be affected by the polymers. We discuss how a set of equations can be derived for the problem and how these equations can be solved numerically by an iterative scheme. By carrying out such a scheme, we find that the effect of the polymers is equivalent to producing a space-dependent effective viscosity that first increases from the zero-shear value at the plate then decreases rapidly back to the zero-shear value far from the plate. We further show that such an effective viscosity leads to an enhancement in the drag, which in turn leads to a reduction in heat transport.

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Roberto Benzi, Emily S. C. Ching., Vivien W. S. Chu. 2011-04-23. Heat transport by laminar boundary layer flow with polymers. https://doi.org/10.1017/jfm.2012.46

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