State estimation of turbulent channel flow

The challenges involved in state estimation of wall-bounded turbulent flows are considered through computational experiments using a variety of measurement strategies (including wall information only). These experiments are part of a larger ongoing effort to develop high fidelity estimates of turbulent flows using the Ensemble Kalman Filter, a method used widely within the weather forecasting community, and other related estimation strategies. This study, which attempts to quantify rigorously the ``propagation of information'' in turbulent flows, might also help to shed some new light on various ``top-down" versus ``bottom-up'' hypotheses currently being debated in the literature on near-wall and highly-sheared turbulent flows.