Relationship between turbulence modulation and skewness in wall bounded flows

Abstract

Recent investigations into wall-bounded turbulent flows have shown a nonlinear scale interaction, whereby the large-scale motion amplitude modulates the small-scale structures (Hutchins & Marusic, 2007b). Mathis et al. (2009) developed a scheme to quantify the degree of modulation using a decoupling procedure, based on the Hilbert transformation applied to the filtered small-scale component of the fluctuating streamwise velocity; and highlighted the similarity between the wall-normal evolution of the degree of amplitude modulation and the skewness profile. This became the topic of study by Schlatter & Örlü (2010), who questioned this technique (at least at low Reynolds number) for unambiguou..