and

The simulation of highly viscoelastic fluid flow problems is still plagued with the so-called high Weissenberg problem (HWP). The Weissenberg number We is the ratio of the magnitude of the elastic forces to that of the viscous forces. Most (if not all) numerical methods lose conver-gence i.e. fail to generate any result and/or fail to generate convergent solutions with respect to mesh size, at small or moderate Weissenberg numbers, limiting their use in industrial flow situations. Recently, a log-conformation formulation was proposed by Fattal and Kupferman [1] and further implemented in Hulsen, Fattal and Kupferman [2]. The main idea is to formulate the constitutive equation in terms of the conformation tensor instead of the extra-stress tensor. More precisely, the constitu-tive equation is written in terms of the logarithm of the positive definite conformation tensor which is therefore well defined. This idea is new for viscoelastic fluid flow problems but was already used for the simulatio