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Flow Regime Transition in Air-Molten Carbonate Salt Two-Phase Flow System  

Cho, Yung-Zun (Nuclear Fuel Cycle R&D Group, Korea Atomic Energy Research Institute)
Yang, Hee-Chul (Nuclear Fuel Cycle R&D Group, Korea Atomic Energy Research Institute)
Eun, Hee-Chul (Nuclear Fuel Cycle R&D Group, Korea Atomic Energy Research Institute)
Kang, Yong (Department of Chemical Engineering, Chungnam National University)
Publication Information
Korean Chemical Engineering Research / v.47, no.4, 2009 , pp. 481-487 More about this Journal
Abstract
In this of study, effects of input air velocity(0.05~0.22 m/sec) and molten carbonate salt temperature ($870{\sim}970^{\circ}C$) on flow regime transition have been studied by adopting a drift-flux model of air holdup and a stochastic analysis of differential pressure fluctuations in an air-molten sodium carbonate salt two-phase system(molten salt oxidation process). Air holdup where the flow regime transition begins was determined by air holdup-drift flux plot. The air holdup value which the flow regime transition begins was increased with increasing molten carbonate salt temperature due to the decrease of viscosity and surface tension of molten carbonate salt. To characterize the flow regime transition more quantitatively, differential pressure fluctuation signals have been analyzed by adopting the stochastic method such as phase space portraits and Kolmogorov entropy, The Kolmogorov entropy decreased with an increasing of molten carbonate salt temperature but increased gradually with an increase in an air velocity, however, it exhibited different tendency with the flow regime and the air velocity value which flow regime transition begins was same to the results of drift-flux analysis.
Keywords
Air-molten Carbonate Salt; Molten Salt Oxidation; Flow Regime transition; Drift-flux Model; Kolmogorov Entropy;
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Times Cited By KSCI : 2  (Citation Analysis)
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