A Study on the Turbulent Flow in Concentric Annuli with Both Rough Walls

양벽면에 거칠기가 있는 이중동심관내의 난류유동에 관한 연구

Fully developed turbulent flow through three concentric annuli with both the rough inner and outer walls was experimentally investigated for a Reynolds number range Re = 15, 000 - 85, 000. Measurements were carried out for the pressure drop, the positions of zero shear stress and maximum velocity, and the velocity distributions in annuli of radius ratios, ${\alpha}$=0.26, 0.4 and 0.56, respectively. The experimental results showed that the positions of zero shear stress and maximum velocity were only weakly dependent on the Reynolds number.