The Influence of Polymer Additives On Turbulent Energy Distribution In Fully-Developed Channel Flows

The mean velocity and pressure fields for turbulent flows of constant property viscoelastic fluids are governed by the continuity equation and the Reynolds averaged Cauchy (RAC-) equation. The RAC-equation is an exact, unclosed equation for the mean velocity. Closure requires a model for the mean Cauchy stress and for the Reynolds stress. In this paper, a recently developed closure for the normalized Reynolds (NR-) stress for turbulent flows of viscous fluids (Koppula, et al., 2009) is extended to turbulent flows of viscoelastic fluids (Virk, 1975; Lyons and Petty, 1985; Brostow, 2008; White and Mungal, 2008). The results are used to predict the influence of polymer additives on the NR-stress in fully-developed channel flows.

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