On the accuracy, robustness, and performance of high order interpolation schemes for the overset method on unstructured grids

Abstract A comprehensive study on interpolation schemes used in overset grid techniques is here presented. Based a literature review, numerous are implemented, and their robustness, accuracy, performance assessed. Two code verification exercises performed for this purpose: 2D analytical solution of laminar Poiseuille steady flow; an intricate manufactured turbulent flow case, characteristic boundary layer combined with unsteady separation bubble. For both cases, the influence layouts, refinement, time‐step investigated. Local global errors, convergence orders, mass imbalance quantified. In terms computational performance, strong scalability, cpu timings, load imbalancing, domain connectivity information (DCI) overhead reported. The effect overset‐grid numerical solver, that is, number nonlinear iterations, also scrutinized. results show that, second order finite volume code, once diffusion dominant (low Reynolds number), higher than order, example, least squares degree 2, needed not to increase total discretization errors. convection dominated flows (high numbers), suggest schemes, nearest cell gradient , sufficient prevent taint underlying by single‐process parallel communication optimization, (with DCI done externally CFD code) may be less 4% run time second‐order 8% third‐order ones, therefore empowering higher‐order more accurate solutions.