ISSN:
1432-1114
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract A single, fully wettable, neutrally buoyant, small radioactive particle and 16 scintillation detectors are utilized to monitor particle motion in gas-liquid bubble columns of different heights and diameters and at different gas superficial velocities. Instantaneous velocities, time-averaged velocities, Reynolds stresses and eddy diffusivities are computed from the particle position versus time data. Anisotropy, indicated by the data, was confirmed by Hurst's rescaled R/S analysis of the fluctuating velocities. For the radial direction, Hurst's exponent is about 0.5 in agreement with a random walk (diffusion)-type mechanism, while in the axial direction, Hurst's exponent of about 0.7 indicates the persistence of long-range effects.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00188499
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