The transfer of energy in drag reducing viscoelastic flows is analyzed through a sequence of energetic budgets that include the mean and turbulent kinetic energy, and the mean polymeric kinetic energy and mean elastic potential energy. Within the context of single-point statistics, this provides a complete picture of the energy exchange between the mean, turbulent and polymeric fields. The analysis utilizes direct simulation data of a fully developed channel flow at a moderately high friction Reynolds number of 1000 and at medium (30%) and high (58%) drag reduction levels using a FENE-P polymeric model. While such a parameter range is not complete, it hopefully is sufficiently broad to facilitate a better understanding of the underlying energetic exchange that occurs within the flow and of the underlying cause of the polymer drag reduction phenomenon.
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