Visibility analysis of boundary layer transition

We study the transition to turbulence in a flat plate boundary layer by means of visibility analysis velocity time-series extracted across flow domain. By taking into account mutual sampled values, graphs are constructed from each time series. The latter are, thus, transformed geometrical object, whose main features can be explored using measures typical network science that provide reduced order representation underlying properties. Using these metrics, we observe evolution laminarity and effects exerted free-stream turbulence. Different other methods requiring an extensive amount spatiotemporal data (e.g., full field) or set parameters thresholds arbitrarily chosen user, present network-based approach is able identify onset markers for streamwise alone.