Electronic Journal of Differential Equations, Vol. 2006(2006), No. 59, pp. 1-35. Title: Well-posedness of one-dimensional Korteweg models Authors: Sylvie Benzoni-Gavage (Univ. Claude Bernard Lyon I, France) Raphael Danchin (Univ. Paris XII, France) Stephane Descombes (UMPA, ENS Lyon, France) Abstract: We investigate the initial-value problem for one-dimensional compressible fluids endowed with internal capillarity. We focus on the isothermal inviscid case with variable capillarity. The resulting equations for the density and the velocity, consisting of the mass conservation law and the momentum conservation with Korteweg stress, are a system of third order nonlinear dispersive partial differential equations. Additionally, this system is Hamiltonian and admits travelling solutions, representing propagating phase boundaries with internal structure. By change of unknown, it roughly reduces to a quasilinear Schrodinger equation. This new formulation enables us to prove local well-posedness for smooth perturbations of travelling profiles and almost-global existence for small enough perturbations. A blow-up criterion is also derived. Submitted June 14, 2004. Published May 2, 2006. Math Subject Classifications: 76N10, 76T10. Key Words: Capillarity; Korteweg stress; local well-posedness; Schrodinger equation.