Document Type : Research Paper
Authors
1 Department of Mechanical Engineering, University of Tehran, Tehran, Iran
2 University of Tehran
3 university of tehran
Abstract
One of the newest of viscoelastic RANS turbulence models for drag reducing channel flow with polymer additives is studied in different flow and rheological properties. In this model, finitely extensible nonlinear elastic-Peterlin (FENE-P) constitutive model is used to describe the viscoelastic effect of polymer solution and turbulence model is developed in the k-ϵ-(ν^2 ) ̅-f framework. The geometry in this study is two-dimensional channel flow and finite volume method (FVM) with a non-uniform collocated mesh is used to solve the momentum and constitutive equations. In order to evaluate this turbulence model, several cases with different parameters such as Reynolds numbers, Weissenberg number, maximum polymer extensibility and concentration of polymer are simulated and assessed against direct numerical simulation (DNS) data. The velocity profiles, shear stress profiles and the percentage of friction drag reduction predicted by this turbulence model are in good agreement with DNS data at moderate to high Reynolds numbers. However, in low Reynolds numbers, the results of model are reliable only for low 〖 L〗^2 value. Moreover, in case of high concentration of polymer, the accuracy of the model is lost.
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