Augustin, Les commentaires des Psaumes. Ps 118, sermons 1-14, Bibliothèque augustinienne 67/A

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Fléchissement élastique, sans allongement, des anneaux et des coques cylindriques elliptiques : étude d'une solution analytique approchée.

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Wall shear stress in a laminar flow through a collapsed tube with wall contact

The present work aims at studying mainly the wall shear stress of a laminar steady flow of an incompressible Newtonian fluid which is conveyed through a collapsed tube with a straight centreline. This tube is composed of a tapered segment, a contact segment where the opposite walls touch and a reopening segment. The tube geometry and steady flow characteristics are obtained from measurements in a collapsed tube. The Navier-Stokes equations associated with the classical boundary conditions are solved using the finite element method. The tridimensional flow results from the tube configuration. In particular, the flow consists of two side-jets due to two tear-drop shaped outer passages in the downstream contact segment associated with reversed flow. In order to compute both the stream-wise and cross-wise components of the shear stress on the wall, a local basis is defined in each wall node. Downstream of the contact segment, flow is separated in two jets which are studied though the help of the velocity field and the wall shear stress

The flattening of elliptical collapsible tubes : study of the contact.

International audienc

Wall shear stress in a laminar flow through a collapsed tube with wall contact

The present work aims at studying mainly the wall shear stress of a laminar steady flow of an incompressible Newtonian fluid which is conveyed through a collapsed tube with a straight centreline. This tube is composed of a tapered segment, a contact segment where the opposite walls touch and a reopening segment. The tube geometry and steady flow characteristics are obtained from measurements in a collapsed tube. The Navier-Stokes equations associated with the classical boundary conditions are solved using the finite element method. The tridimensional flow results from the tube configuration. In particular, the flow consists of two side-jets due to two tear-drop shaped outer passages in the downstream contact segment associated with reversed flow. In order to compute both the stream-wise and cross-wise components of the shear stress on the wall, a local basis is defined in each wall node. Downstream of the contact segment, flow is separated in two jets which are studied though the help of the velocity field and the wall shear stress

Tridimensional flow in uniformly collapsed tubes: wall shear stress

The present work is aimed at studying both the entry length and the wall shear stress in a laminar steady flow of an incompressible Newtonian fluid. The fluid is conveyed through rigid straight tubes with axially uniform cross sections which correspond to the characteristic collapsed states. The cross section shapes have been defined from the collapse of an infinitely long elastic tube subjected to an uniform transmural pressure on its lateral surface. For each tube configuration, the Navier-Stoke

The 3D-structure of critical flow in a collapsed tube

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Computed entry lengths of laminar flow in uniformaly collapsed veins with a flat wall. Applications to flow-subjected cell cultures.

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