Abstract
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=7×104 and Re=106 after having injected (i) small bubbles (R=1 mm) up to a volume concentration of α=5% and (ii) buoyant particles (ρp/ρl=0.14) of comparable volume concentration. In case (i) we observe a crossover from little drag reduction at smaller Re to strong drag reduction up to 20% at Re=106. In case (ii) we observe at most little drag reduction throughout. Several theoretical models for bubbly drag reduction are discussed in view of our findings.
Original language | Undefined |
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Pages (from-to) | 044501-1-044501-4 |
Number of pages | 4 |
Journal | Physical review letters |
Volume | 94 |
Issue number | 4 |
DOIs | |
Publication status | Published - 2005 |
Keywords
- METIS-227770
- IR-54099