Causality analysis of large-scale structures in the flow around a wall-mounted square cylinder

The aim of this work is to analyse the formation mechanisms large-scale coherent structures in flow around a wall-mounted square cylinder, due their impact on pollutant transport within cities. To end, we assess causal relations between modes reduced-order model obtained by applying proper-orthogonal decomposition high-fidelity-simulation data case under study. are identified using conditional transfer entropy, which an information-theoretical quantity that estimates amount information contained past one variable about another. This allows for understanding origins and evolution different phenomena flow, with identifying responsible main vortical structures. Our approach unveils vortex-breaker most modes, particular, over higher-order no significant relationships were found vortex-generator modes. We validate technique determining present nine-equation near-wall turbulence developed Moehlis et al. (New J. Phys, vol. 6, 2004, p. 56), good agreement literature results turbulent channel flows.