Two Point Correlations Between Velocity Sums and Differences, and Their Implications for Large-Small Scale Correlations in Fluid Turbulence

Recent work by Blum, et al has shown the existence of a dependence between large and small scale statistics in measurements of isotropic fluid turbulence, violating the hypothesized universality of small scales in fluid turbulence. The authors have argued that that non-ideal effects, such as inhomogeneity and large scale intermittency are the most likely causes of these dependences. Recent studies of kinematic relations, which seem to imply correlations between large and small scale statistics, have also been suggested as an explanation for the effects seen by Blum,et al. This work has focused on measuring the kinematic relation arrived at by Hosokawa. The first 3–D particle tracking velocimetry measurements of the Hosokawa relation are presented, as well as a discussion on the sensitivity of the relation to inhomogeneous effects. Ultimately, the conclusions in Blum et al are supported, as the Hosokawa relation itself is dominated by inhomogeneity in our flow.