Aerodynamic Computations Using the Convective Upstream Split Pressure Scheme with Local Preconditioning

grantor: University of TorontoThe implementation of the convective upstream split pressure (CUSP) approach to numerical dissipation is presented for an approximately-factored algorithm in conjunction with time-derivative local preconditioning. Two different 'soft' flux limiters, one of which is new, are used to to blend the low and high order CUSP dissipation in order to enforce monotonic solutions. The resulting algorithm is applied to several turbulent aerodynamic flows and compared with results obtained using scalar and matrix numerical dissipation models. The results show the CUSP scheme to be very effective in providing good shock capturing, low numerical dissipation in boundary layers, and low numerical errors in drag. The two flux limiters provide equivalent accuracy; however, a reduction in computational cost was obtained with the newly proposed 'soft' limiter. Overall, the CUSP scheme is competitive with matrix dissipation in terms of accuracy at a reduced cost. For flows with Mach number below 0.2, convergence is significantly accelerated with the preconditioned algorithm, and the preconditioned CUSP scheme is superior to the preconditioned scalar scheme and the original CUSP scheme.M.A.Sc