Drag Reduction in Bubbly Taylor-Couette Turbulence
نویسندگان
چکیده
منابع مشابه
Drag reduction in bubbly Taylor-Couette turbulence.
In Taylor-Couette flow the total energy dissipation rate and therefore the drag can be determined by measuring the torque on the system. We do so for Reynolds numbers between Re=7 x 10(4) and Re=10(6) after having injected (i) small bubbles (R=1 mm) up to a volume concentration of alpha=5% and (ii) buoyant particles (rhop/rhol=0.14) of comparable volume concentration. In case (i) we observe a c...
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Three different polysaccharides, aloe vera, Tamarind powder and pineapple fibers, are utilized as drag reducing agents in a turbulent flow. Using a Taylor–Couette setup, consisting of a rotating inner cylinder, for measuring the drag reduction, a range of Reynolds numbers from 4 × 104 to 3 × 105 has been explored in this study. The results are in good agreement with previous studies on polysacc...
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ژورنال
عنوان ژورنال: Physical Review Letters
سال: 2005
ISSN: 0031-9007,1079-7114
DOI: 10.1103/physrevlett.94.044501