A Second-order Hybrid Rotated Riemann Solver for Multi-dimensional Euler Equations on Unstructured Meshes

A second-order rotational upwind transport scheme for multi-dimensional compressible Euler equations on unstructured meshes is presented.Cell-centered FVM is employed in which gradient calculation is node-based with more neighbor cells.Slope limiter schemes are constructed for unstructured meshes.Numerical fluxes are evaluated by solving two Riemann problems in two upwind directions,including velocity-difference vector and perpendicular direction.The scheme eliminate shock instabilities or carbuncle phenomena in flux-difference splitting type schemes completely.A hybrid rotated Riemann solver is employed to form an economical numeric flux function and base Riemann solvers employ HLL and Roe FDS.