incorporating a restricted nonlinear (RNL) system that retains a single streamwise Fourier
mode, is used. Considering the flow geometry originally used by Monokrousos et al.(2011)
and Duguet et al.(2013) and the same Reynolds numbers (R e), we show that initial
perturbations obtained by RNL optimizations exhibit spatial localization. Two optimal states
are found with comparable initial energy levels above which the flow structure evolves to …