Numerical Analysis of Viscoelastic Start-up Flows in Abrupt Expansion Channel
نویسندگان
چکیده
منابع مشابه
Start-up times in viscoelastic channel and pipe flows
Start-up times in viscoelastic channel and pipe flows generated by the sudden imposition of a pressure gradient are here determined by a mixed analytical/numerical procedure. The rheological models considered are the upper convected Maxwell and the Oldroyd-B equations. With these models the flow evolves asymptotically to the steady state solution after a transient regime presenting strong oscil...
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In this paper, we consider viscoelastic flows in a rough domain (with typical roughness patterns of size ε ≪ 1). We present and rigorously justify an asymptotic expansion with respect to ε, at any order, based upon the definition of elementary problems: Oldroyd-type problems at the global scale defined on a smoothened domain and boundary-layer corrector problems. The resulting analysis guarante...
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ژورنال
عنوان ژورنال: Nihon Reoroji Gakkaishi(Journal of the Society of Rheology, Japan)
سال: 1998
ISSN: 0387-1533
DOI: 10.1678/rheology1973.26.2_103