An adaptive Non-Linear Frequency Domain method for viscous flows

摘要

An adaptive Nonlinear Frequency Domain method (adaptive NLFD) has been developed and validated for the Navier-Stokes equations. Although the compute time for periodic flows is reduced by using the NLFD approach over classical time marching schemes, the adaptive NLFD approach leads to further reductions in the overall computational effort. The adaptive NLFD method is validated for the laminar vortex shedding behind a stationary two-dimensional cylinder. A novel adaptation strategy that allows both mode augmentation and reduction, enables the adaptive approach to gain a factor of two reduction in memory and computational cost at an equivalent solution accuracy to the non-adaptive approach.