APARTIR DES EQUATIONS DE STOKES SUR LE DOMAINE VARIABLE, ON OBTIENT APRES TRANSFORMATION CELLES SUR LE DOMAINE FIXE DE CALCUL. ON APPLIQUE A CES DERNIERES UNE FORMULATION MOINDRES CARRES SUR UN PROBLEME PENALISE QUE L'ON RESOUT PAR UN ALGORITHME DE GRADIENT CONJUGUE. ON APPLIQUE LE MEME GENRE DE RAISONNEMENT AUX EQUATIONS DE NAVIER STOKES. CES DEUX PROBLEMES SONT RESOLUS PAR UNE METHODE D'ELEMENTS FINIS

This volume collects the articles presented at the Third International Conference on “The Navier-Stokes Equations: Theory and Numerical Methods”, held in Oberwolfach, Germany. The articles are important contributions to a wide variety of topics in the Navier-Stokes theory: general boundary conditions, flow exterior to an obstacle, conical boundary points, the controllability of solutions, compressible flow, non-Newtonian flow, magneto-hydrodynamics, thermal convection, the interaction of fluids with elastic solids, the regularity of solutions, and Rothe's method of approximation.

This introductory physical and mathematical presentation of the Navier-Stokes equations focuses on unresolved questions of the regularity of solutions in three spatial dimensions, and the relation of these issues to the physical phenomenon of turbulent fluid motion.

The Navier-Stokes equations describe the motion of fluids and are an invaluable addition to the toolbox of every physicist, applied mathematician, and engineer. The equations arise from applying Newton's laws of motion to a moving fluid and are considered, when used in combination with mass and energy conservation rules, to be the fundamental governing equations of fluid motion. They are relevant across many disciplines, from astrophysics and oceanic sciences to aerospace engineering and materials science. This Student's Guide provides a clear and focused presentation of the derivation, significance and applications of the Navier-Stokes equations, along with the associated continuity and energy equations. Designed as a useful supplementary resource for undergraduate and graduate students, each chapter concludes with a selection of exercises intended to reinforce and extend important concepts. Video podcasts demonstrating the solutions in full are provided online, along with written solutions and other additional resources.