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arXiv · 0804.2536

Intermittency and rough-pipe turbulence

Mohammad Mehrafarin·Nima Pourtolami
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Abstract

Recently, by analyzing the measurement data of Nikuradze, it has been proposed (N. Goldenfeld, Phys. Rev. Lett. {\bf{96}}, 044503, 2006) that the friction factor, $f$, of rough pipe flow obeys a scaling law in the turbulent regime. Here, we provide a phenomenological scaling argument to explain this law and demonstrate how intermittency modifies the scaling form, thereby relating $f$ to the intermittency exponent, $η$. By statistically analyzing the measurement data of $f$, we infer a satisfactory estimate for $η$ ($\approx 0.02$), the inclusion of which is shown to improve the data-collapse curve. This provides empirical evidence for intermittency other than the direct measurement of velocity fluctuations.

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Mohammad Mehrafarin, Nima Pourtolami. 2008-04-16. Intermittency and rough-pipe turbulence. https://doi.org/10.1103/physreve.77.055304

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