Écoulement dans un convergent axisymétrique: calcul de la contrainte de cisaillement pariétale maximale

The maximal wall shear stress (MWSS) in the convergent part of a stenosis is computed as a function of characteristic geometrical parameters (stenosis degree and length), of the entry velocity profile and of flow Reynolds number, by means of the Interactive Boundary-Layer (IBL) theory, in the simplified case where the flow is axisymmetric and stationary. The independence of the MWSS on the entry velocity profile is showed. A heuristic analysis, followed by regression analysis of the numerical results, allows drawing out the simple dependence of the MWSS on the other parameters, all measurable in clinical practice. The so obtained relationship extends the results found in the literature, achieved by resolution of Navier-Stokes equations for particular geometrical characteristics.