High-accurate and robust conservative remapping combining polynomial and hyperbolic tangent reconstructions

In this article we present a 1D single-material conservative remapping method that relies on high accurate reconstructions: polynomial (P 4 , P 1 with slope limiter) and non-linear hyperbolic tangent (THINC) representations. Such remapping procedure is intended to be used pairwise with a cell-centered Lagrangian scheme along with a rezone strategy to build a so-called indirect Arbitrary-Lagrangian-Eulerian scheme. Most of practically used Lagrangian schemes are second-order accurate. The goal of this work is to handle with accuracy contact using THINC reconstructions. At the same time, the smooth part of the solution is dealt with quartic polynomials, resulting locally in fifth order accurate remapping method. To ensure robustness, TVD-like reconstructions (P 1 with slope limiter) are employed otherwise. A simple feature tracking algorithm is designed to assign a reconstruction type per cell (P 4 , P lim 1 or THINC). This tracking algorithm is based on the nature of the contact waves which are traveling at the fluid velocity, while the shocks are compressive and detectable by following a change of cell volumes. Numerical results assess the behavior of such a remapping method on pure remapping problems of a scalar quantity and in the context of the full hydrodynamics equations. The associated indirect cell-centered ALE numerical scheme is run and produces numerical results that are presented to assess the extreme accuracy gained by such a remapping procedure employing a mix of reconstruction types