Mean velocity profile in high Re-number turbulent boundary layer: Its universality and recent progress

Yoshiyuki TSUJI Nagoya University	Atsushi IDO Railway technical research institute	Michio Nishioka Osaka Prefecture University

Abstract

High Reynolds number turbulent boundary layer measurement is performed in the Railway Technical Research Institute’s low-noise wind tunnel in Maibara Japan (Fig.1). The momentum thickness Reynolds number is up to approximately 8×10⁴. Using the friction velocity measured by oil film interferometry, mean velocity profile shows a clear log-law region with Kármán constant 0.38 (Fig.2). The turbulent intensity profile also shows the log-law scaling predicted by attached eddy model. However, the log-regions of mean and turbulent intensity do not match with each other. It is found that Kármán constant , additive constant , and wake parameter  relate closely with each other.

Keywords

Turbulence, Turbullent boundary layer, Mean velocity profile, High Reynolds number, Universality

Figures

Fig.1 Wind tunnel facility at Railway technical research institute (RTRI) wind tunnel technical center
(http://www.rtri.or.jp/rd/maibara-wt/INDEX.HTML).

 

Fig.2 Mean velocity profiles measured at x=14.4m with .
Mean velocity is normalized by inner variables. Solid line is Eq.(1) with  and .