Turbulence Intensity and the Friction Factor for Smooth- and Rough-Wall Pipe Flow
نویسنده
چکیده
Abstract: Turbulence intensity profiles are compared for smoothand rough-wall pipe flow measurements made in the Princeton Superpipe. The profile development in the transition from hydraulically smooth to fully rough flow displays a propagating sequence from the pipe wall towards the pipe axis. The scaling of turbulence intensity with Reynolds number shows that the smoothand rough-wall level deviates with increasing Reynolds number. We quantify the correspondence between turbulence intensity and the friction factor.
منابع مشابه
Turbulent flow in smooth and rough pipes.
Recent experiments at Princeton University have revealed aspects of smooth pipe flow behaviour that suggest a more complex scaling than previously noted. In particular, the pressure gradient results yield a new friction factor relationship for smooth pipes, and the velocity profiles indicate the presence of a power-law region near the wall and, for Reynolds numbers greater than about 400x103 (R...
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