EFFECT OF VISCOELASTICITY ON THE FAR-DISSIPATION RANGE OF HOMOGENEOUS ISOTROPIC TURBULENCE etc15 Tracking Number 320Presentation: Session: Multiphase and non-Newtonian flows 4 Room: Room D Session start: 10:30 Fri 28 Aug 2015 Minh Quan NGUYEN minh-quan.nguyen@ec-lyon.fr Affifliation: LMFA UMR 5509 CNRS, Ecole Centrale de Lyon, Université de Lyon, France Serge Simöens serge.simoens@ec-lyon.fr Affifliation: LMFA UMR 5509 CNRS, Ecole Centrale de Lyon, Université de Lyon, France Alexandre Delache alexandre.delache@univ-st-etienne.fr Affifliation: LMFA, site de Saint-Etienne, Université de Lyon, Université Jean Monnet de Saint-Etienne, France Mahmoud El Hajem mahmoud.elhajem@insa-lyon.fr Affifliation: LMFA UMR 5509 CNRS, INSA de Lyon, Université de Lyon, France Wouter Bos wouter.bos@ec-lyon.fr Affifliation: LMFA UMR 5509 CNRS, Ecole Centrale de Lyon, Université de Lyon, France Robert Poole robpoole@liverpool.ac.uk Affifliation: School of Engineering, University of Liverpool, United Kingdom Topics: - Turbulence in multiphase and non-Newtonian flows Abstract: The comparison of the results of direct numerical simulations of isotropic turbulence of Newtonian and viscoelastic fluid, based on the FENE-P model, provide evidence that viscoelasticity modifies qualitatively the behavior of the smallest scales: we observe a k−6 law in the far dissipation range of the energy spectrum and we show that it is a robust feature, roughly independent of the large-scale dynamics. It is further shown that the drag-reduction in such flows, as measured by the difference in energy dissipation between Newtonian and viscoelastic flow, strongly depends on the initial conditions. |