@article { ISI:000253622800027,
	title = {Experimental analysis of the lift force on bubbles in a swarm},
	journal = {Chemical Engineering Science},
	volume = {63},
	number = {6},
	year = {2008},
	month = {OCT},
	pages = {1710-1723},
	publisher = {PERGAMON-ELSEVIER SCIENCE LTD},
	type = {Article},
	address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND},
	abstract = {<p>The lift force acting on bubbles in a swarm has been estimated by analyzing the instantaneous velocity-time data obtained using LDA in a cylindrical bubble column. Phase distinction was achieved through the multiresolution analysis of the velocity-time data. Several important issues related to the transverse motion of bubbles subjected to a shear field have been discussed quantitatively. The actually measured bubble sizes, the respective slip velocity values in transverse and axial directions and the local shear rates (gamma) enabled the verification of known formulations for the lift coefficient (C-L) for bubbles. At many locations in the column the radial flux of the gas phase by turbulent dispersion and the radial slip were estimated. The radially inward movement of bubbles from low to high axial velocity (from column wall to center, i.e., C-L \&lt; 0) was observed at most of the measurement locations. The local lift coefficient was estimated using the transverse drag force and the values support the results from the material balance approach. The estimated C-L values showed a wide variation over the column cross-section. (c) 2007 Elsevier Ltd. All rights reserved.</p>},
	keywords = {Bubble, Bubble column, bubble size, hydrodynamics, LDA, lift force},
	doi = {10.1016/j.ces.2007.10.029},
	author = {Kulkarni, Amol A.}
}
@article { ISI:000261281100001,
	title = {SVR-based prediction of point gas hold-up for bubble column reactor through recurrence quantification analysis of LDA time-series},
	journal = {International Journal of Multiphase Flow},
	volume = {34},
	number = {12},
	year = {2008},
	month = {DEC},
	pages = {1099-1107},
	publisher = {PERGAMON-ELSEVIER SCIENCE LTD},
	address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND},
	abstract = {<p>Recurrence quantification analysis (RQA) has emerged as a useful tool for detecting singularities in nonstationary time-series data. In this paper, we use RQA to analyze the velocity-time data acquired using laser doppler anemometry (LDA) signals in a bubble column reactor for Single point and Multipoint point spargers. The recurring dynamical states within the velocity-time-series occurring due to the bubble and the liquid passage at the point of measurement, are quantified by RQA features (namely \% Recurrence, \% Determinism, \% Laminarity and Entropy), which in turn are regressed using support vector regression (SVR) to predict the point gas hold-up values. It has been shown that SVR-based model for the bubble column reactor can be potentially useful for online prediction and monitoring of the point gas hold-up for different sparging conditions. (C) 2008 Elsevier Ltd. All rights reserved.</p>},
	keywords = {Bubble column, Gas hold-up, LDA, Recurrence quantification analysis (RQA), Support vector regression (SVR)},
	issn = {0301-9322},
	doi = {10.1016/j.ijmultiphaseflow.2008.07.001},
	author = {Gandhi, Ankit B. and Joshi, J. B. and Kulkarni, A. A. and Jayaraman, Valadi K. and Kulkarni, B. D.}
}
