Vortical flow simulations by a high-order accurate unstructured hexahedral grid method

Vortical flows over a delta wing are numerically simulated by unstructured high-order accurate methods using flux reconstruction (FR) approach by Huynh. The order of accuracy of the scheme for a two-dimensional vortex convection is first tested on various types of grids and with some flux correction functions. Cares for calculating the derivative of the flux polynomial are shown. The flow over a delta wing is then simulated by the fourth order (polynomial degree 3, or p3) and third order (p2) FR as well as the structured MUSCL approach for the comparison. The p3 FR shows the highest suction peak due to the leading-edge vortices and the p2 results are closer to the p3 regardless of the smaller degrees of freedom than the case of MUSCL calculation.