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arXiv · 2210.06087

Visibility analysis of boundary layer transition

Davide Perrone·Luca Ridolfi·Stefania Scarsoglio
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Abstract

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

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Davide Perrone, Luca Ridolfi, Stefania Scarsoglio. 2022-10-12. Visibility analysis of boundary layer transition. https://doi.org/10.1063/5.0106455

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