The effect of viscoelasticity on the turbulent kinetic energy cascade

• Tipo: Artigo em Revista Científica Internacional
• Data: 2014

Autores

P. C. Valente (Autor) Outra; C. B. da Silva (Autor) Outra; F. T. Pinho (Autor) FEUP

Revista

Título: Journal of Fluid Mechanics

Vol. 760 Nº 6

Páginas: 39-62

ISSN: 0022-1120

Editora: Cambridge University Press

Indexação

ISI Web of Knowledge - 15 Citações

ISI Web of Science

Scopus - 29 Citações

INSPEC

Classificação Científica

FOS: Ciências da engenharia e tecnologias > Engenharia mecânica

Projetos Associados

TURBELAST - TURBELAST - Modelos de turbulência para fluídos viscoelásticos: abordagem RANS e LES

Outras Informações

ID Authenticus: P-009-Z7J

DOI: 10.1017/jfm.2014.585

Abstract (EN): Direct numerical simulations of statistically steady homogeneous isotropic turbulence in viscoelastic fluids described by the FENE-P model, such as those laden with polymers, are presented. It is shown that the strong depletion of the turbulence dissipation reported by previous authors does not necessarily imply a depletion of the nonlinear energy cascade. However, for large relaxation times, of the order of the eddy turnover time, the polymers remove more energy from the large scales than they can dissipate and transfer the excess energy back into the turbulent dissipative scales. This is effectively a polymer-induced kinetic energy cascade which competes with the nonlinear energy cascade of the turbulence leading to its depletion. It is also shown that the total energy flux to the small scales from both cascade mechanisms remains approximately the same fraction of the kinetic energy over the turnover time as the nonlinear energy cascade flux in Newtonian turbulence.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 24