Numerical analysis and decoupled approach for the problem of non-Newtonianfluids flows of Phan-Thien-Tanner model: discontinuous stresses

We present in this work a numerical analysis of a decoupled approach with d iscontinuous stresses for the viscoelastic fluid flows obeying to the Phan- Thien-Tanner model. The Lesaint-Raviart method is used to treat the transpo rt part of the equations. In comparaison with the classical Oldroyd model, this model introduces supplementary difficulties linked to the non-linearit ies of the exponential type present in the constitutive equation. The inter est of this work lies in the fact that it allows to decouple the constituti ve equation and the momentum equations. (C) 2000 Academie des sciences/Edit ions scientifiques et medicales Elsevier SAS.