An adaptive conservative ALE approach to deal with large boundary displacements in three-dimensional inviscid simulations

The present work proposes an innovative adaptive finite-volume scheme for compressible inviscid flows that automatically guarantees the solution to be conservative. The major novelty of this approach concerns the interpretation of local modifications due to mesh adaptation, which are treated as a series of fictitious continuous deformations. These deformations are taken into account in a conservative way by adding additional fictitious fluxes to the Arbitrary-Lagrangian-Eulerian (ALE) formulation of the governing equations and the solution on the new grid is recovered without any explicit interpolation. This feature makes the proposed approach well-suited for moving-body problems characterized by large boundary movements, as assessed by numerical simulations of the piston-induced shock-tube problem and of the transonic flow around a wing performed in the laboratory reference frame.