Energy cascade analysis in a viscoelastic turbulent flow: DNS of homogeneous and isotropic turbulence in a viscoelastic fluid

by Antonio Mosca

Direct numerical simulations (DNS) of homogeneous and isotropic turbulence in a viscoelastic fluid are done in order to study the kinetic energy transfers and the structures of the correspondent turbulent field, in both physical and Fourier spaces. The numerical algorithm is based on pseudo-spectral methods and the rheology of the fluid is represented by using the finitely extensible non-linear elastic rheological constitutive model with Peterlin approximation (FENE-P). The energy cascade is studied by analysing the energy transfer between large and small flow scales in different zones of the energy spectrum. The separation between scales is done using filtering operations in the physical space and the results are analysed using statistical tools. With the results obtained is possible to plan how to do LES of viscoelastic turbulent flows.

108 pages, Paperback

Published January 8, 2018