Journal articles: 'Bubble column'

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Reeder, D. Benjamin, John E. Joseph, Thomas A. Rago, Jeremy M. Bullard, David Honegger, and Merrick C. Haller. "Acoustic spectrometry of bubbles in an estuarine front: Sound speed dispersion, void fraction, and bubble density." Journal of the Acoustical Society of America 151, no. 4 (April 2022): 2429–43. http://dx.doi.org/10.1121/10.0009923.

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Estuaries constitute a unique waveguide for acoustic propagation. The spatiotemporally varying three-dimensional front between the seawater and the outflowing freshwater during both flood and ebb constitutes an interfacial sound speed gradient capable of supporting significant vertical and horizontal acoustic refraction. The collision of these two water masses often produces breaking waves, injecting air bubbles into the water column; the negative vertical velocities of the denser saltwater often subduct bubbles to the bottom of these shallow waveguides, filling the water column with a bubbly mixture possessing a significantly lower effective sound speed. A field experiment was carried out in the mouth of Mobile Bay, Alabama in June 2021 to characterize estuarine bubble clouds in terms of their depth-dependent plume structure, frequency-dependent sound speed and attenuation, bubble size distribution, bubble number density, and void fraction. Results demonstrate that sound speed in the bubbly liquid consistently falls below the intrinsic sound speed of bubble-free water; specifically, the bubbly liquid 1.3 m below the surface in a front in this environment possesses effective sound speeds, void fractions, and bubble number densities of approximately 750 m/s, 0.001%, and 2 × 106 bubbles/m3, respectively.

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MUDDE, ROBERT F., and TAKAYUKI SAITO. "Hydrodynamical similarities between bubble column and bubbly pipe flow." Journal of Fluid Mechanics 437 (June 22, 2001): 203–28. http://dx.doi.org/10.1017/s0022112001004335.

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The hydrodynamical similarities between the bubbly flow in a bubble column and in a pipe with vertical upward liquid flow are investigated. The system concerns air/water bubbly flow in a vertical cylinder of 14.9 cm inner diameter. Measurements of the radial distribution of the liquid velocity, gas fraction and the bubble velocity and size are performed using laser Doppler anemometry for the liquid velocity and a four-point optical fibre probe for the gas fraction, bubble velocity and size. The averaged gas fraction was 5.2% for the bubble column (with a superficial liquid velocity of zero) and 5.5% for the bubbly pipe flow at a superficial liquid velocity of 0.175 m s−1. From a hydrodynamical point of view, the two modes of operation are very similar. It is found that in many respects the bubbly pipe flow is the superposition of the flow in the bubble column mode and single-phase flow at the same superficial liquid velocity.The radial gas fraction profiles are the same and the velocity profiles differ only by a constant offset: the superficial liquid velocity. This means that the well-known large-scale liquid circulation (in a time-averaged sense) of the bubble column is also present in the bubbly pipe flow. For the turbulence intensities it is found that the bubbly pipe flow is like the superposition of the bubble column and the single-phase flow at the superficial liquid velocity of the pipe flow, the former being at least an order of magnitude higher than the latter. The large vortical structures that have been found in the bubble columns are also present in the bubbly pipe flow case, partly explaining the much higher ‘turbulence’ levels observed.

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Ariny Demong, Andrew Ragai Rigit, and Khairuddin Sanaullah. "Effect of Swirl Gas Injection on Bubble Characteristics in a Bubble Column." Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 102, no. 2 (February 27, 2023): 155–65. http://dx.doi.org/10.37934/arfmts.102.2.155165.

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Swirling gas injection is a well-known technique to improve mass transfer in bubble columns. It can be used to create small bubbles with a high surface area-to-volume ratio, which is beneficial for mass transfer. Swirl gas injection can also be used to create a more uniform bubble size distribution and improve the mixing of gas and liquid in the column. This study aims to determine the impact of swirl gas injection on bubble properties, including bubble shape, size, and velocity. A bubble detection approach has been developed for quick and precise determination of bubble size distributions in gas-liquid systems. Advanced digital image processing, including edge detection and bubble edge recognition, is used in this method. The experiment is conducted in a bubble column at a height of 57 cm and 61 cm. The column had a ring sparger and was made of Plexiglas. Tap water was used as the liquid, while air from an air compressor was utilized as the gas phase. The shape, size, population, and velocity of the bubble are measured using a high-speed digital camera. According to this study, the average bubble size reduced as the impeller speed increased, while the population of bubbles increased when the sparger rotation speed increased from 30 to 150 rpm.

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Tian, Ye, Hua Qian, and Qiu Hong Ke. "A Bubble Detection Algorithm Based on Wavelet Transform and Canny Operator for Deinked Pulp Flotation Column." Applied Mechanics and Materials 278-280 (January 2013): 1162–66. http://dx.doi.org/10.4028/www.scientific.net/amm.278-280.1162.

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Deinked pulp flotation column has been applied in wastepaper recycling. Bubble size in deinked pulp flotation column is very important during the flotation process. In this paper, bubble images of deinked pulp flotation column are first caught by digital camera, and then the bubbles are detected by using a bubble detection algorithm based on wavelet transform and canny operators. The results show the algorithms are very practical and effective on bubble detection in deinked pulp flotation column.

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Bastani, Dariush, Ali Baghaei, and Amir Sarrafi. "“Bubble Bunch” phenomenon in operation of a bubble column." Open Chemistry 7, no. 4 (December 1, 2009): 803–8. http://dx.doi.org/10.2478/s11532-009-0081-4.

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AbstractWhile studying the operation of a rectangular bubble column in laboratory scale, it was observed that under certain circumstances tiny bubbles attach to larger bubbles without causing them to coalesce. In other words, bubbles with large diameters (d > 5 mm) swept tiny bubbles (d

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Mosdorf, Romuald, Tomasz Wyszkowski, and Kamil Dąbrowski. "Multifractal properties of large bubble paths in a single bubble column." Archives of Thermodynamics 32, no. 1 (April 1, 2011): 3–20. http://dx.doi.org/10.2478/v10173-011-0001-9.

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Multifractal properties of large bubble paths in a single bubble columnIn the paper the paths of bubbles emitted from the brass nozzle with inner diameter equal to 1.6 mm have been analyzed. The mean frequency of bubble departure was in the range from 2 to 65.1 Hz. Bubble paths have been recorded using a high speed camera. The image analysis technique has been used to obtain the bubble paths for different mean frequencies of bubble departures. The multifractal analysis (WTMM - wavelet transform modulus maxima methodology) has been used to investigate the properties of bubble paths. It has been shown that bubble paths are the multifractals and the influence of previously departing bubbles on bubble trajectory is significant for bubble departure frequencyfb> 30 Hz.

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Battistella, Alessandro, Sander Aelen, Ivo Roghair, and Martin van Sint Annaland. "Euler–Lagrange Modeling of Bubbles Formation in Supersaturated Water." ChemEngineering 2, no. 3 (August 24, 2018): 39. http://dx.doi.org/10.3390/chemengineering2030039.

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Phase transition, and more specifically bubble formation, plays an important role in many industrial applications, where bubbles are formed as a consequence of reaction such as in electrolytic processes or fermentation. Predictive tools, such as numerical models, are thus required to study, design or optimize these processes. This paper aims at providing a meso-scale modelling description of gas–liquid bubbly flows including heterogeneous bubble nucleation using a Discrete Bubble Model (DBM), which tracks each bubble individually and which has been extended to include phase transition. The model is able to initialize gas pockets (as spherical bubbles) representing randomly generated conical nucleation sites, which can host, grow and detach a bubble. To demonstrate its capabilities, the model was used to study the formation of bubbles on a surface as a result of supersaturation. A higher supersaturation results in a faster rate of nucleation, which means more bubbles in the column. A clear depletion effect could be observed during the initial growth of the bubbles, due to insufficient mixing.

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Weber, Andreas, and Hans-Jörg Bart. "Flow Simulation in a 2D Bubble Column with the Euler-lagrange and Euler-euler Method." Open Chemical Engineering Journal 12, no. 1 (January 25, 2018): 1–13. http://dx.doi.org/10.2174/1874123101812010001.

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Object: Bubbly flows, as present in bubble column reactors, can be simulated using a variety of simulation techniques. It is presented, how Computational Fluid Dynamics (CFD) methods are used to simulate a pseudo 2D bubble column using Euler-Lagrange (EL) and Euler-Euler (EE) techniques. Method: The presented EL method uses the open access software OpenFOAM to solve bubble dynamics with bubble interactions computed via Monte Carlo methods. The estimated bubble size distribution and the predicted hold-up are compared with experimental data and other simulative EE work with a reasonable consensus for both. Benchmarks with state of the art EE simulations shows that the EL approach shows good performance if the bubble number stays at a certain level, as the EL approach scales linearly with the number of bubbles simulated. Therefore, different computational meshes have been used to account for influence of the resolution quality. Conclusion: The EL approach indicated faster solution for all realistic cases, only deliberate decrease of coalescence rates could push CPU time to the limits. Critical bubble number - when EE becomes superior to the EL approach - was estimated to be 40.000 in this particular case.

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Ning, Chen, and Fang Bing Wang. "Numerical Simulation of Hydrodynamics in Slurry Bubble Column Reactor." Applied Mechanics and Materials 303-306 (February 2013): 2679–82. http://dx.doi.org/10.4028/www.scientific.net/amm.303-306.2679.

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Gas dispersion and solid suspension in industrial size slurry bubble column reactors for producing sodium dichromate are simulated numerically by using of computational fluid dynamics (CFD). The Eulerian multi-fluid model and standard k-ε turbulence model are used to describe the flow behavior in bubble columns. The simulated results show that gas is easy to flow toward the centre of the bubble column and in relatively high local gas holdup there. Installing gas-re-distributors in the bubble column is favorable for gas dispersion. Solid suspension in the bubble columns under the operating condition we investigated is relatively uniform.

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Zhang, Xinyu, and Goodarz Ahmadi. "Numerical Simulations of Liquid-Gas-Solid Three-Phase Flows in Microgravity." Journal of Computational Multiphase Flows 4, no. 1 (March 2012): 41–63. http://dx.doi.org/10.1260/1757-482x.4.1.41.

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Three-phase liquid-gas-solid flows under microgravity condition are studied. An Eulerian-Lagrangian computational model was developed and used in the simulations. In this approach, the liquid flow was modeled by a volume-averaged system of governing equations, whereas motions of particles and bubbles were evaluated using the Lagrangian trajectory analysis procedure. It was assumed that the bubbles remained spherical, and their shape variations were neglected. The bubble-liquid, particle-liquid and bubbl-particle two-way interactions were accounted for in the analysis. The discrete phase equations used included drag, lift, buoyancy, and virtual mass forces. Particle-particle interactions and bubble-bubble interactions were accounted for by the hard sphere model. Bubble coalescence was also included in the model. The transient flow characteristics of the three-phase flow were studied; and the effects of gravity, inlet bubble size and g-jitter acceleration on variation of flow characteristics were discussed. The low gravity simulations showed that most bubbles are aggregated in the inlet region. Also, under microgravity condition, bubble transient time is much longer than that in normal gravity. As a result, the Sauter mean bubble diameter, which is proportional to the transient time of the bubble, becomes rather large, reaching to more than 9 mm. The bubble plume in microgravity exhibits a plug type flow behavior. After the bubble plume reaches the free surface, particle volume fraction increases along the height of the column. The particles are mainly located outside the bubble plume, with very few particles being retained in the plume. In contrast to the normal gravity condition, the three phases in the column are poorly mixed under microgravity conditions. The velocities of the three phases were also found to be of the same order. Bubble size significantly affects the characteristics of the three-phase flows under microgravity conditions. For the same inlet bubble number density, the flow with larger bubbles evolves faster. The simulation results showed that the effect of g-jitter acceleration on the gas-liquid-particle three phase flows is small.

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Cheng, Yixuan, Qiong Zhang, Pan Jiang, Kaidi Zhang, and Wei Wei. "Investigation of Plume Offset Characteristics in Bubble Columns by Euler–Euler Simulation." Processes 8, no. 7 (July 7, 2020): 795. http://dx.doi.org/10.3390/pr8070795.

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Based on low-cost and easy to enlarge, the bubble column device has been widely concerned in chemical industry. This paper focuses on bubble plumes in laboratory-scale three-dimensional rectangular air-water columns. Static behavior has been investigated in many experiments and simulations, and our present investigations consider the dynamic behavior of bubble plume offset in three dimensions. The investigations are conducted with a set of closure models by the Euler–Euler approach, and subsequently, literature data for rectangular bubble columns are analyzed for comparison purposes. Moreover, the transient evolution characteristics of the bubble plume in the bubble column and the gas phase distribution in sections are introduced, and the offset characteristics and the oscillation period of the plume are analyzed. In addition, the distributions of the vector diagram of velocity and vortex intensity in the domain are given. The effects of different fluxes and column aspect ratios on bubble plumes are studied, and the offset and plume oscillation period (POP) characteristics of bubbles are examined. The investigations reveal quantitative correlations of operating conditions (gas volume flux) and aspect ratios that have not been reported so far, and the simulated and experimental POP results agree well. An interesting phenomenon is that POP does not occur under conditions of a high flux and aspect ratio, and the corresponding prediction values for the conditions with and without POP are given as well. The results reported in this paper may open up a new way for further study of the mass transfer of bubble plumes and development of chemical equipment.

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Saha, Avik, and Arup Kumar Das. "Bubble dynamics in concentric multi-orifice column under normal and reduced gravity." Physics of Fluids 34, no. 4 (April 2022): 042113. http://dx.doi.org/10.1063/5.0086740.

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A bubble column with concentrically arranged orifices has been numerically simulated in this article. Bubble growth, departure, and rise have been studied stage-wise to understand the effect of the neighboring orifice and bubbles on these phenomena. A dissimilar inflow condition through the orifices has also been applied in simulations to make out the effect of asymmetric interfacial interaction on the overall performance of the bubble column. Furthermore, the effect of reduced gravity on the bubble departure volume, frequency, and interaction has also been analyzed. A new scheme of the intermittent inflow has been proposed to reduce the bubble size and improve the bubble column performance. An effort has also been made to analytically predict the minimum bubble size from the basic understanding of the departure mechanism for both continuous and intermittent flow conditions. For further improvement of the bubble column performance, the effect of inflow velocity and on time for intermittent flow has been studied, and the rationale of making the right choice of those parameters has been discussed.

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Arunkumar, S., V. Harshavardhan Reddy, T. M. Sreevathsav, and M. Venkatesan. "Hydrodynamic Study of Bubbles in a Bubble Column Reactor Part II – Numerical Study." Applied Mechanics and Materials 813-814 (November 2015): 1023–27. http://dx.doi.org/10.4028/www.scientific.net/amm.813-814.1023.

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The present work deals with the use of CFD analysis and the validation of the experimental work carried out on the artificial splitting of an air bubble in a bubble column reactor. In Part I of this work, artificial splitting of bubble in a bubble column rector is experimentally studied by using a high speed camera. Image processing technique was used to identify bubble size and bubble velocity. In present work CFD simulations are carried out using ANSYS FLUENT software using Volume of Fluids (VOF) method. VOF is based on a surface tracking technique applied to a fixed Eulerian space. The phase fraction in physical quantities that can be used to distinguish the distribution of gas hold up in a bubble Column reactor. The numerical study of splitting of bubble into two bubbles of nearly equal size is considered. In the bubble column reactor, the liquid phase is stationary and gas flow rate in it is varied. The superficial gas flow rates are 10 lph, 15 lph, 20 lph and 25 lph. The characteristics of bubble after splitting which include its shape, size and velocity for various gas flow rates mentioned above are studied numerically and are compared with experimental results. These hydrodynamic characteristics play a pivotal role in the reactions occurring between the liquid and gas phases in the bubble column reactor.

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Hayder Abd Al-kaream Muhsin. "EXPERIMENTAL STUDY OF LIQUID DISPERSION IN BUBBLE COLUMN." Diyala Journal of Engineering Sciences 1, no. 1 (September 1, 2008): 56–85. http://dx.doi.org/10.24237/djes.2008.01105.

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The main object of this study is to investigate the influence of column diameter and superficial gas velocity on liquid phase dispersion coefficients (axial and radial dispersion coefficients), mixing times, gas holdup, and bubble dynamics (bubble diameter and rise velocity). The liquid phase dispersion, gas holdup, and bubble dynamics (Db and Vb0) were measured for the air-water system in bubble columns of two different diameters,15 and 30 cm. The superficial gas velocity, Ug, was varied in the range 1-10 cm/s, spanning both the homogeneous and heterogeneous flow regimes. The height of liquid in the column was kept constant at 130 cm for the two column. Axial and radial dispersion coefficients and mixing times were measured at various axial and radial locations inside the columns (Z = 25, 75, 125 cm and r/R = 0, 0.45, 0.85), bubble dynamics were measured at three axial location (Z=25, 75, 125 cm). From the experimental data it was found that, the value of the radial dispersion coefficient (Dr,L) and axial dispersion coefficient (Dax,L), gas holdup, bubble diameter and bubble rise velocity, increase with increasing superficial gas velocity. The results emphasise the significant influence of the column diameter on the hydrodynamics. Gas holdup showed a decrease with increasing column diameter, while the radial dispersion coefficient (Dr,L), axial dispersion coefficient (Dax,L), bubble diameter and bubble rise velocity increased with increasing column diameter. A statistical analysis was performed to get a general correlations for the axial liquid dispersion coefficient as a function of the mixing time and dispersion height (Hd), this correlations are: Dax,L=0.15 H2d /θ0.3 for 30 cm column diameter and Dax,L=0.11 H2d /θ0.3 for 15 cm column diameter.

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Reis, Angelica Silva, A. M. R. Filho, G. R. L. Carvalho, and Marcos Antonio de Souza Barrozo. "Effect of Surfactant on Bubble Size and Air Holdup on Column Flotation." Materials Science Forum 899 (July 2017): 71–76. http://dx.doi.org/10.4028/www.scientific.net/msf.899.71.

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Flotation is a complex process in which is present physicochemical and hydrodynamic phenomena. The flotation performance is related to the probability of bubble-particle collisions and stability of aggregate formed. The collision efficiency is a function of particle and bubble diameters. Currently one of the biggest challenges of the mining industry is the flotation of fine and ultrafine particles and a possible solution to increase the recovery of these fine particles is the use of bubbles with intermediate size (100-1000μm). Therefore, determining and controlling the bubble size is very important for further recoveries in the flotation of fine particles. It is known that the bubble size and air holdup are influenced by variations on the superficial gas velocity and by addition of surfactants. Thus this work aimed to study the effect of adding surfactants on bubbles formation. The results showed that the addition of surfactant was a good alternative to decrease bubble size and increase the air holdup in a bubble column. Three different surfactants had similar behavior on bubble size and holdup. It was possible to define the range of concentration values which are sufficient for forming bubbles with intermediate size and holdup within the range recommended for mineral flotation.

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Agarwal, Neha, Moonyong Lee, and Hyunsung Kim. "A Non-Invasive Method for Measuring Bubble Column Hydrodynamics Based on an Image Analysis Technique." Processes 10, no. 8 (August 21, 2022): 1660. http://dx.doi.org/10.3390/pr10081660.

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Bubble size and its distribution are the important parameters which have a direct impact on mass transfer in bubble column reactors. For this, a new robust image processing technique was presented for investigating hydrodynamic aspects and bubble behavior in real chemical or biochemical processes. The experiments were performed in a small-scale bubble column. The study was conducted for the wide range of clear liquid heights and superficial gas velocities. However, a major challenge in image analysis techniques is identification of overlapping or cluster bubbles. This problem can be overcome with the help of the proposed algorithm. In this respect, large numbers of videos were recorded using a high-speed camera. Based on detailed experiments, the gas–liquid dispersion area was divided into different zones. A foam region width was found as inversely proportional to the clear liquid height. An entry region width was found as directly proportional to the clear liquid height. Hydrodynamic parameters, including gas holdup, bubble size distribution, and Sauter mean bubble diameter were evaluated and compared for different operating conditions. The gas holdup was calculated from both height measurement and pixel intensity methods, and it was found to be indirectly proportional to clear liquid height. Bubble sizes affect the bubble column performance; therefore, bubbles are tracked to calculate the bubble size distribution. Experimental results proved that the proposed scheme is robust.

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Hills, JohnH. "Bubble Column Reactors." Chemical Engineering Science 47, no. 15-16 (October 1992): 4221. http://dx.doi.org/10.1016/0009-2509(92)85172-8.

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Kantarci, Nigar, Fahir Borak, and Kutlu O. Ulgen. "Bubble column reactors." Process Biochemistry 40, no. 7 (June 2005): 2263–83. http://dx.doi.org/10.1016/j.procbio.2004.10.004.

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Sato, Hiroyasu, Mohd Hatta bin Mohd Akbar, Kosuke Hayashi, and Akio Tomiyama. "OS21-1-3 Assessment of turbulence models for bubbly flow in a bubble column." Abstracts of ATEM : International Conference on Advanced Technology in Experimental Mechanics : Asian Conference on Experimental Mechanics 2011.10 (2011): _OS21–1–3—. http://dx.doi.org/10.1299/jsmeatem.2011.10._os21-1-3-.

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Naveen, S., T. Sriram, S. Prithvi Raj, and M. Venkatesan. "Hydrodynamic Study of Bubbles in a Bubble Column Reactor Part I – Image Processing." Applied Mechanics and Materials 813-814 (November 2015): 1018–22. http://dx.doi.org/10.4028/www.scientific.net/amm.813-814.1018.

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The study of bubble column reactors has its significance in applications such as multiphase reactors, aerators and in industrial waste-water treatment. Extensive works has been done in studying the hydrodynamics of a single gas bubble flowing through stationary liquid phase. The natural breakup of bubble during its motion has been studied in the past. In the Part I of the present work, hydrodynamics of an air bubble after its artificial splitting using a stainless steel mesh is experimentally studied using image processing and high speed photography. The significance of bubble splitting is that it increases the surface area of contact between stationery and moving fluid which in turn increases the rate of reaction desired during the process. The motion of the bubble is captured during its release and after splitting using High-Speed Camera. The velocity, area and diameter of the bubble before and after splitting are calculated by applying Image processing technique on the high speed photograph. The splitting of the bubble is found to vary with the superficial gaseous velocity. The splitting of bubbles into two bubbles of nearly equal size is considered and its hydrodynamic characteristics are studied.

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Zhang, Junping, Norman Epstein, John R. Grace, and Kokseng Lim. "Bubble Characteristics in a Developing Vertical Gas–Liquid Upflow Using a Conductivity Probe." Journal of Fluids Engineering 122, no. 1 (October 12, 1999): 138–45. http://dx.doi.org/10.1115/1.483250.

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Experiments were carried out in an 82.6-mm-dia column with a perforated distributor plate. Conductivity probes on the axis of the column were used to measure local bubble properties in the developing flow region for superficial air velocities from 0.0018 to 6.8 m/s and superficial water velocities from 0 to 0.4 m/s, corresponding to the discrete bubble, dispersed bubble, coalesced bubble, slug, churn, bridging, and annular flow regimes. Bubble frequency increased linearly with gas velocity in the discrete and dispersed bubble regimes. Bubble frequency also increased with gas velocity in the slug flow regime, but decreased in the churn and bridging regimes. Bubble chord length and its distribution were smaller and narrower in the dispersed than in the discrete bubble regime. Both the average and standard deviation of the bubble chord length increased with gas velocity in the discrete, dispersed, and churn flow regimes. However, the average bubble chord length did not change significantly in the slug flow regime due to the high population of small bubbles in the liquid plugs separating Taylor bubbles. The bubble travel length, defined as the product of local gas holdup and local bubble velocity divided by local bubble/void frequency, is used to correlate bubble characteristics and to characterize the flow regimes. [S0098-2202(00)00101-2]

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Besagni, Giorgio, and Fabio Inzoli. "Prediction of Bubble Size Distributions in Large-Scale Bubble Columns Using a Population Balance Model." Computation 7, no. 1 (March 12, 2019): 17. http://dx.doi.org/10.3390/computation7010017.

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A precise estimation of the bubble size distribution (BSD) is required to understand the fluid dynamics in gas-liquid bubble columns at the “bubble scale,” evaluate the heat and mass transfer rate, and support scale-up approaches. In this paper, we have formulated a population balance model, and we have validated it against a previously published experimental dataset. The experimental dataset consists of BSDs obtained in the “pseudo-homogeneous” flow regime, in a large-diameter and large-scale bubble column. The aim of the population balance model is to predict the BSD in the developed region of the bubble column using as input the BSD at the sparger. The proposed approach has been able to estimate the BSD correctly and is a promising approach for future studies and to estimate bubble size in large-scale gas–liquid bubble columns.

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Youssef, Ahmed A., Muthanna H. Al-Dahhan, and Milorad P. Dudukovic. "Bubble Columns with Internals: A Review." International Journal of Chemical Reactor Engineering 11, no. 1 (June 18, 2013): 169–223. http://dx.doi.org/10.1515/ijcre-2012-0023.

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Abstract Most industrial bubble column reactors require the utilization of internal structures for heat transfer and/or for controlling the flow structures and back mixing in the system. The internals denote all types of innards added to a bubble column, such as perforated plates, baffles, vibrating helical springs, mixers, and heat exchanger tubes. In commercial scale bubble columns, instrumentation probes, down-comers, and risers with heat exchangers are all considered. This review presents the state-of-knowledge of bubble columns with internals. It starts with an introduction. The second section discusses the horizontal internals, and the following section examines the studies involving vertical internals.

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Tao, Fangfang, Shanglei Ning, Bo Zhang, Haibo Jin, and Guangxiang He. "Simulation Study on Gas Holdup of Large and Small Bubbles in a High Pressure Gas–Liquid Bubble Column." Processes 7, no. 9 (September 4, 2019): 594. http://dx.doi.org/10.3390/pr7090594.

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The computational fluid dynamics-population balance model (CFD-PBM) has been presented and used to evaluate the bubble behavior in a large-scale high pressure bubble column with an inner diameter of 300 mm and a height of 6600 mm. In the heterogeneous flow regime, bubbles can be divided into “large bubbles” and “small bubbles” by a critical bubble diameter dc. In this study, large and small bubbles were classified according to different slopes in the experiment only by the method of dynamic gas disengagement, the critical bubble diameter was determined to be 7 mm by the experimental results and the simulation values. In addition, the effects of superficial gas velocity, operating pressure, surface tension and viscosity on gas holdup of large and small bubbles in gas–liquid two-phase flow were investigated using a CFD-PBM coupling model. The results show that the gas holdup of small and large bubbles increases rapidly with the increase of superficial gas velocity. With the increase of pressure, the gas holdup of small bubbles increases significantly, and the gas holdup of large bubbles increase slightly. Under the same superficial gas velocity, the gas holdup of large bubbles increases with the decrease of viscosity and the decrease of surface tension, but the gas holdup of small bubbles increases significantly. The simulated values of the coupled model have a good agreement with the experimental values, which can be applied to the parameter estimation of the high pressure bubble column system.

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Mohagheghian, Shahrouz, Afshin J. Ghajar, and Brian R. Elbing. "Effect of Vertical Vibration on the Mixing Time of a Passive Scalar in a Sparged Bubble Column Reactor." Fluids 5, no. 1 (January 4, 2020): 6. http://dx.doi.org/10.3390/fluids5010006.

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The present study used a sparged bubble column to study the mixing of a passive scalar under bubble-induced diffusion. The effect of gas superficial velocity (up to 69 mm/s) and external vertical vibrations (amplitudes up to 10 mm, frequency <23 Hz) on the mixing time scale were investigated. The bubble-induced mixing was characterized by tracking the distribution of a passive scalar within a sparged swarm of bubbles. Void fraction and bubble size distribution were also measured at each test condition. Without vibrations (static), the bubble column operated in the homogenous regime and the mixing time scale was insensitive to void fraction, which is consistent with the literature. In addition, the temporal evolution of the static column mixing was well approximated as an error function. With vertical vibrations at lower amplitudes tested, the bubble-induced mixing was restrained due to the suppression of the liquid velocity agitations in the bubble swarm wake, which decelerates mixing. Conversely, at higher amplitudes tested, vibration enhanced the bubble-induced mixing; this is attributed to bubble clustering and aggregation that produced void fraction gradients, which, in turn, induced a mean flow and accelerated the mixing. The vibration frequency for the range studied in the present work did not produce a significant effect on the mixing time. Analysis of the temporal evolution of the concentration of the passive scalar at a fixed point within the column revealed significant fluctuations with vibration. A dimensionally reasoned correlation is presented that scales the non-dimensional mixing time with the transient buoyancy number.

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Prakash, Ritesh, Bongliba T. Sangtam, Kalicharan Hembrom, and Subrata Kumar Majumder. "Bubble size analysis in a two-phase countercurrent flow in the narrow rectangular column." Physics of Fluids 34, no. 4 (April 2022): 043305. http://dx.doi.org/10.1063/5.0083749.

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The flow of bubbles in a two-phase system has great implications in chemical, petrochemical, and biochemical applications. This work enunciates the measurement of bubble size distribution and bubble aspect ratio in three-different axial zones in the countercurrent flow mode with a gas and liquid velocity range of 0.044–0.321 and 0.019–0.058 m/s, respectively. Bubble size is measured by the photographic technique. The bubble aspect ratio and bubble size distribution results reveal that the impact of gas and liquid velocities is significant on the Sauter mean bubble size. The Sauter mean bubble size increases as the gas velocity increases, whereas it decreases with the liquid velocity. The Sauter mean bubble diameter ranges from 2.65 to 6.16 mm. The distribution of bubble sizes follows the LogLogistic probability density function. In addition, a correlation is also proposed for the interpretation of bubble diameter in terms of Reynolds number and Froude number. The bubble aspect ratio changes with axial zones and gas and liquid velocities. Experiments reveal that the bubble aspect increases with liquid velocity while decreasing with gas velocity and axial zones. The bubble aspect ratio correlations are developed in terms of Eötvös and Reynolds numbers. The present results will be helpful for the process intensification of bubble-aided two-phase flow applications.

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Ishiyama, Hiroshi, Haruki Kaneoka, Jun Sawai, and Hiromitsu Kojima. "The Latest Frontiers of Bubble Columns and Slurry Bubble Columns. Gas Holdup and Bubble Behaviour in a Pressurized Bubble Column." KAGAKU KOGAKU RONBUNSHU 27, no. 4 (2001): 480–83. http://dx.doi.org/10.1252/kakoronbunshu.27.480.

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Lau, Raymond, Rujuan Mo, and Wei Shan Beverly Sim. "Bubble characteristics in shallow bubble column reactors." Chemical Engineering Research and Design 88, no. 2 (February 2010): 197–203. http://dx.doi.org/10.1016/j.cherd.2009.07.008.

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Abdulrazzaq, Burhan Sadeq. "Gas Holdup and Liquid-Phase Dispersion in Packed Bubble Columns." Tikrit Journal of Engineering Sciences 18, no. 3 (September 30, 2011): 13–22. http://dx.doi.org/10.25130/tjes.18.3.02.

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The gas holdup and liquid phase axial dispersion coefficient are measured in two semi batch packed bubble columns, 10 and 15 cm diameter for an air–water system, at atmospheric conditions. The experiments were carried out using a transient method (the tracer response method). The dispersion coefficient was obtained by adjusting the experimental profiles of tracer concentration with the predictions of the model. Experiment results of packed bubble column, shows a considerable reduction of the back mixing. The investigations have been carried out using RTD measurements and the back mixing is usually characterized by the axial dispersion coefficient obtained from the one-dimensional axial dispersion model. Also, a decrease in superficial gas velocity reduces the liquid back mixing. It is observed that the liquid circulation comprises an upward flow in the column core and a downward flow along the wall. It also seen that the transition from the bubbly flow to the pulsation flow regime occurred at 5-6 cm/s superficial gas velocity.

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Li, Nan, Mingchen Cao, Kun Xu, Jiabin Jia, and Hangben Du. "Ultrasonic Transmission Tomography Sensor Design for Bubble Identification in Gas-Liquid Bubble Column Reactors." Sensors 18, no. 12 (December 4, 2018): 4256. http://dx.doi.org/10.3390/s18124256.

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Scientists require methods to monitor the distribution of gas bubbles in gas-liquid bubble column reactors. One non-destructive method that can potential satisfy this requirement in industrial situations is ultrasonic transmission tomography (UTT). In this paper, an ultrasonic transmission tomography sensor is designed for measuring bubble distribution in a reactor. Factors that influence the transducer design include transmission energy loss, the resonance characteristics and vibration modes of the transducer, and diffusion angles of the transducers, which are discussed. For practical application, it was found that an excitation frequency of 300 kHz could identify the location and size of gas bubbles. The vibration mode and diffusion also directly affect the quality of the imaging. The geometric parameters of the transducer (a cylinder transducer with a 10 mm diameter and 6.7 mm thickness) are designed to achieve the performance requirements. A UTT system, based on these parameters, was built in order to verify the effectiveness of the designed ultrasonic transducer array. A Sector-diffusion-matrix based Linear Back Projection (SLBP) was used to reconstruct the gas/liquid two-phase flow from the obtained measurements. Two other image processing methods, based on SLBP algorithm named SLBP-HR (SLBP-Hybrid Reconstruction) and SLBP-ATF (SLBP-Adaptive Threshold Filtering), were introduced, and the imaging results are presented. The imaging results indicate that a gas bubble with a 3 mm radius can be identified from reconstructed images, and that three different flow patterns, namely, single gas bubble, double gas bubble with different diameters, and eccentric flow, can be identified from reconstructed images. This demonstrates that the designed UTT sensor can effectively measure bubble distribution in gas-liquid bubble column reactors.

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Hadavand, Laleh, and Ali Fadavi. "Effect of Vibrating Sparger on Mass Transfer, Gas Holdup, and Bubble Size in a Bubble Column Reactor." International Journal of Chemical Reactor Engineering 11, no. 1 (June 18, 2013): 47–56. http://dx.doi.org/10.1515/ijcre-2012-0094.

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Abstract Bubble size has a key role in gas holdup and mass transfer in bubble column reactors. In order to have small and uniform bubbles, a new structure was designed; the reactor operates in two modes, with vibrating sparger and conventional bubble column in which sparger is fixed. In vibrating mode, the sparger vibrates gently during gas entering. The vibrating sparger performs like a paddle, resulting in a forced recirculation of gas–liquid inside the reactor; moreover, the bubble detachment is accelerated. The superficial gas velocity was between 0.003 and 0.013 ms− 1, and the vibration frequency was changed between 0 and 10.3 Hz. The bubble size was measured at three various positions of the reactor height by photographic method and using MATLAB 7.0.1 software. The mass transfer coefficient was determined by means of the dynamic gassing-out method. The results show that the bubbles were bigger in vibrating mode than those working without vibration. The bubble size decreases with increase in height from sparger. Gas holdup increased with increase in superficial gas velocity and vibration frequency. The effect of vibration increased the gas holdup with an average of 70% for all superficial gas velocities. Volumetric mass transfer coefficient was almost stable as vibration frequency increased.

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32

Lerner, Y., H. Kalman, and R. Letan. "Condensation of an Accelerating-Decelerating Bubble: Experimental and Phenomenological Analysis." Journal of Heat Transfer 109, no. 2 (May 1, 1987): 509–17. http://dx.doi.org/10.1115/1.3248112.

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An experimental and theoretical phenomenological study of accelerating–decelerating bubbles, condensing in an immiscible liquid, was conducted. The system consisted of a column of water, and bubbles of freon-113, 4–5×10−3 m in diameter. Shadowgraphing of the process has illustrated the wake formation behind the bubble, wake shedding, forward movement of vortices, and envelopment of the decelerating bubble in its wake. The bubble size, shape, and path were videotaped and analyzed for the collapse rate, and the instantaneous position. The visualized hydrodynamic phenomena provided a phenomenological basis for the theoretical formulations. The theoretical model postulated an eccentrically positioned vapor sphere in the collapsing bubble, a boundary layer and wake over the accelerating bubble, and a concentric vorticular envelope around the decelerating bubble. The theoretical–phenomenological predictions compared well with experiment.

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Hanna, Fadi Z., and Ihsan B. Hamawand. "Bubbles Coalescence Frequency and Transition Concentration in Bubble Column." Tikrit Journal of Engineering Sciences 13, no. 4 (December 31, 2006): 73–95. http://dx.doi.org/10.25130/tjes.13.4.04.

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Bubbles coalescence frequency and the transition concentration in a dispersion column were studied experimentally by using ethanol-water mixture as a liquid phase and air as a gas phase. The study was devoted to express the effect of the liquid properties on the performance of the dispersion column, and the experimental work was designed for this purpose, where the range of weight percent of ethanol in water, (0.1-0.7) Wt%, and the range of superficial gas velocity of air, (2.5-30) mm/s. The experimental runs were planned using the central composite routable design method. The experimental data obtained agreed quite well with a polynomial type of correlations by using computer program. The experimental data shows that the values of bubble coalescence decrease with increasing superficial gas velocity of air, and ethanol transition concentration was successfully correlated as a function of the superficial gas velocity of air, ct= 0.158214 − 0.010849Ug + 0.00045Ug2 − 0.000008Ug3 . This equation gives mean deviation of 10.393%.

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34

Martín, Mariano, Francisco J. Montes, and Miguel A. Galán. "Mass transfer from oscillating bubbles in bubble column reactors." Chemical Engineering Journal 151, no. 1-3 (August 2009): 79–88. http://dx.doi.org/10.1016/j.cej.2009.01.046.

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35

Muroyama, Katsuhiko, Yuji Oka, and Ryota Fujiki. "Transport Properties of Micro-Bubbles in a Bubble Column." JOURNAL OF CHEMICAL ENGINEERING OF JAPAN 45 (2012): 666–71. http://dx.doi.org/10.1252/jcej.12we066.

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36

Bartsch, Achim. "Beschleunigung des Stoffaustausches von Gas-Flüssigkeits-Reaktionen durch Schallwellen am Beispiel der Fetthärtung." Zeitschrift für Naturforschung A 50, no. 2-3 (March 1, 1995): 228–34. http://dx.doi.org/10.1515/zna-1995-2-315.

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Abstract A method for increasing the mass transfer in gas/liquid-reactions by application of sonic vibration is described. The operating frequencies have been chosen such that the surfaces of the gas bubbles vibrate in resonance. At these operating frequencies (up to 1000 Hz), the damping of sound waves by the bubbly liquid is low, which is important in large-scale applications. Hydrogenation of soybean oil in a bubble column has been carried out as a test reaction. An increase in mass transfer from dispersed bubbles to the liquid in terms of kLaG of up to 36% has been effected by a relatively small amount of sonic power.

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Sujan, Ajay, and Raj K. Vyas. "A review on empirical correlations estimating gas holdup for shear-thinning non-Newtonian fluids in bubble column systems with future perspectives." Reviews in Chemical Engineering 34, no. 6 (November 27, 2018): 887–928. http://dx.doi.org/10.1515/revce-2016-0062.

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Abstract Gas holdup is one of the most important parameters for characterizing the hydrodynamics of bubble columns. Modeling and design of bubble columns require empirical correlations for precise estimation of gas holdup. Empirical correlations available for prediction of gas holdup (εG) in various non-Newtonian systems for both gas-liquid and gas-liquid-solid bubble columns have been presented in this review. Critical analysis of correlations presented by different researchers has been made considering the findings and pitfalls. As the magnitude of gas holdup depends on many factors, such as physicochemical properties of gas and/or liquid, column geometry, type and design of gas distributors, operating conditions, phase properties, and rheological properties, etc., all of these have been discussed and examined. In order to emphasize the significance, relative importance of parameters such as flow behavior index, consistency index, column diameter, gas flow rate, and density of aqueous carboxymethylcellulose (CMC) solution on gas holdup has been quantified using artificial neural network and Garson’s algorithm for an experimental data set of air-CMC solution from the literature. Besides, potential areas for research encompassing operating conditions, column geometry, physical properties, modeling and simulation, rheological properties, flow regime, etc., have been underlined, and the need for developing newer correlations for gas holdup has been outlined. The review may be useful for the modeling and design of bubble columns.

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38

Wu, Chengtian, Kelsey Suddard, and Muthanna H. Al-dahhan. "Bubble dynamics investigation in a slurry bubble column." AIChE Journal 54, no. 5 (2008): 1203–12. http://dx.doi.org/10.1002/aic.11459.

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39

Ribeiro, J. A., A. S. Reis, P. S. Avendaño, C. H. Ataíde, and Marcos A. S. Barrozo. "Experimental and CFD Simulation of a Bubble Column." Materials Science Forum 727-728 (August 2012): 1824–29. http://dx.doi.org/10.4028/www.scientific.net/msf.727-728.1824.

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The numerical simulation in fluid mechanics has large application in chemical engineering. The objective of the present work is the analyze of a computational model for the fluid dynamics behaviour of a bubble column of the geometry cylindrical non regular with multiphase mixture. Experimental data and CFD results of the hydrodynamics of gaseous and liquid phases have been compared. Five different diameters of bubbles have been used in the CFD simulations. The comparisons between CFD simulations and experimental data show that the Eulerian-Eulerian approach provides a computational model that represents the process satisfactorily.

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40

Schneider von Deimling, J., and C. Papenberg. "Technical Note: Detection of gas bubble leakage via correlation of water column multibeam images." Ocean Science Discussions 8, no. 4 (July 15, 2011): 1757–75. http://dx.doi.org/10.5194/osd-8-1757-2011.

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Abstract. Hydroacoustic detection of natural gas release from the seafloor has been conducted in the past by using singlebeam echosounders. In contrast modern multibeam swath mapping systems allow much wider coverage, higher resolution, and offer 3-D spatial correlation. However, up to the present, the extremely high data rate hampers water column backscatter investigations. More sophisticated visualization and processing techniques for water column backscatter analysis are still under development. We here present such water column backscattering data gathered with a 50 kHz prototype multibeam system. Water column backscattering data is presented in videoframes grabbed over 75 s and a "re-sorted" singlebeam presentation. Thus individual gas bubbles rising from the 24 m deep seafloor clearly emerge in the acoustic images and rise velocities can be determined. A sophisticated processing scheme is introduced to identify those rising gas bubbles in the hydroacoustic data. It applies a cross-correlation technique similar to that used in Particle Imaging Velocimetry (PIV) to the acoustic backscatter images. Tempo-spatial drift patterns of the bubbles are assessed and match very well measured and theoretical rise patterns. The application of this processing scheme to our field data gives impressive results with respect to unambiguous bubble detection and remote bubble rise velocimetry. The method can identify and exclude the main driver for misinterpretations, i.e. fish-mediated echoes. Even though image-based cross-correlation techniques are well known in the field of fluid mechanics for high resolution and non-inversive current flow field analysis, this technique was never applied in the proposed sense for an acoustic bubble detector.

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41

TOMITA, Y., T. SAITO, and S. GANBARA. "Surface breakup and air bubble formation by drop impact in the irregular entrainment region." Journal of Fluid Mechanics 588 (September 24, 2007): 131–52. http://dx.doi.org/10.1017/s0022112007007483.

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Drop impact on a water surface can be followed by underwater sounds originating not at the drop impact but when the entrained bubbles oscillate. Although the sound mechanism in the regular bubble entrainment region is well-known, there is less knowledge on the impact phenomena in the irregular bubble entrainment region where various situations can exist, such as many types of bubble formation or even no bubble generation under some conditions. In the present study, the aim is to clarify the dynamics of the water surface after the impact of a primary drop, mainly with diameter 5.2, 5.7 and 6.2mm, each of which is accompanied by a single satellite drop. Special attention was paid to the breakup behaviour of the water surface for Froude number Fr < 300. It was found that three underwater sounds were generated for a single drop impact, besides the sound due to impact itself. The first two were audible to the human ear, but the third one was almost inaudible. The first underwater sound resulted from the oscillation of a single air bubble formed as a result of the satellite drop impact on the bottom of the contracting cavity, and the second sound was due to the oscillation of air bubbles generated during the collapse of the water column. The formation of these air bubbles strongly depends on the Froude number, Weber number (or Bond number) and the aspect ratio of the drop at impact, although involving probability characteristics. Furthermore it is suggested that an air bubble entrapped in a water column plays an important role in increasing the probability of contact between the column surface and the curved free surface. A Japanese Suikinkutsu was introduced as an application of drop-impact-induced sounds. Using an open-type Suikinkutsu an additional experiment was carried out with larger drops with average diameters of 6.2, 7.2 and 7.8, mm.

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42

Yamagiwa, K., M. Yoshida, A. Ohkawa, and S. Takesono. "Biological treatment of highly foaming pharmaceutical wastewater by modified bubble-column under mechanical foam control." Water Science and Technology 42, no. 3-4 (August 1, 2000): 331–37. http://dx.doi.org/10.2166/wst.2000.0399.

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Activated sludge treatment of highly foaming pharmaceutical wastewater was carried out with modified bubble columns equipped with a mechanical foam-breaker (MFRD). The geometry of the bubble column was modified based on the foam breaking mechanism of the MRFD in order to improve the foam breaking capacity and hence to enhance the treatment capacity. Four types of modifications were examined. The activated sludge treatment of the wastewater with the modified columns was successfully carried out with COD removal efficiency about 90% at BOD loading of 4 g/Ld. Little effect of the mechanical foam control on the sludge settling characteristics was observed. The column modification significantly reduced the power required for foam control. The maximum power decrement of 75% was attained. Furthermore, oxygen transfer was found to be facilitated in the modified bubble columns. The results are expected to be helpful for economic and effective treatment of highly foaming organic wastewater.

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43

Bae, Keon, Gang Seok Go, Nam Seon Noh, Young-Il Lim, JongWook Bae, and Dong Hyun Lee. "Bubble characteristics in pressurized bubble column associated with micro-bubble dispersion." Chemical Engineering Journal 386 (April 2020): 121339. http://dx.doi.org/10.1016/j.cej.2019.03.215.

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Gvozdić, Biljana, Elise Alméras, Varghese Mathai, Xiaojue Zhu, Dennis P. M. van Gils, Roberto Verzicco, Sander G. Huisman, Chao Sun, and Detlef Lohse. "Experimental investigation of heat transport in homogeneous bubbly flow." Journal of Fluid Mechanics 845 (April 20, 2018): 226–44. http://dx.doi.org/10.1017/jfm.2018.213.

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We present results on the global and local characterisation of heat transport in homogeneous bubbly flow. Experimental measurements were performed with and without the injection of ${\sim}2.5~\text{mm}$ diameter bubbles (corresponding to bubble Reynolds number $Re_{b}\approx 600$) in a rectangular water column heated from one side and cooled from the other. The gas volume fraction $\unicode[STIX]{x1D6FC}$ was varied in the range 0 %–5 %, and the Rayleigh number $Ra_{H}$ in the range $4.0\times 10^{9}{-}1.2\times 10^{11}$. We find that the global heat transfer is enhanced up to 20 times due to bubble injection. Interestingly, for bubbly flow, for our lowest concentration $\unicode[STIX]{x1D6FC}=0.5\,\%$ onwards, the Nusselt number $\overline{Nu}$ is nearly independent of $Ra_{H}$, and depends solely on the gas volume fraction $\unicode[STIX]{x1D6FC}$. We observe the scaling $\overline{Nu}\,\propto \,\unicode[STIX]{x1D6FC}^{0.45}$, which is suggestive of a diffusive transport mechanism, as found by Alméras et al. (J. Fluid Mech., vol. 776, 2015, pp. 458–474). Through local temperature measurements, we show that the bubbles induce a huge increase in the strength of liquid temperature fluctuations, e.g. by a factor of 200 for $\unicode[STIX]{x1D6FC}=0.9\,\%$. Further, we compare the power spectra of the temperature fluctuations for the single- and two-phase cases. In the single-phase cases, most of the spectral power of the temperature fluctuations is concentrated in the large-scale rolls/motions. However, with the injection of bubbles, we observe intense fluctuations over a wide range of scales, extending up to very high frequencies. Thus, while in the single-phase flow the thermal boundary layers control the heat transport, once the bubbles are injected, the bubble-induced liquid agitation governs the process from a very small bubble concentration onwards. Our findings demonstrate that the mixing induced by high Reynolds number bubbles ($Re_{b}\approx 600$) offers a powerful mechanism for heat transport enhancement in natural convection systems.

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Khorasanizadeh, Narjes, Mohammad Karamoozian, and Hossein Nouri-Bidgoli. "An investigation of the effect of initial bubble diameter on the bubble trajectory in the flotation column cell using CFD simulation." Rudarsko-geološko-naftni zbornik 38, no. 2 (2022): 55–66. http://dx.doi.org/10.17794/rgn.2022.2.5.

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The effect of initial bubble diameter on the bubble motion pattern in a flotation column has been studied by the twophase computational fluid dynamics (CFD) method. The two-phase simulations have been done using the volume of a fluid (VOF) model in ANSYS® Fluent® software. The computational field was a square cross-section column with a width of 0.1 m and a height of 1 m into which air was interred as a single bubble from the lower part of the column by an internal sparger. An experimental test has been also performed and the simulated results have been validated using the values obtained for the bubble rise velocity. A comparison of the simulation and the experimental results has confirmed that CFD can predict the bubble rise velocity profile and its value in the flotation column less than 5% relative to the experimental values. Then the simulations have been repeated with a 20% decrease and increase in the initial bubble diameter to investigate the effect of bubble diameter on the bubble flow pattern. The investigations have shown that as the bubble diameter increases, the velocity decreases and the bubble rises in a more zigzag direction as a result of two counter-rotating trailing vortices behind the bubble increasing.

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46

Bando, Yoshiyuki, Makoto Chaya, Keiji Yasuda, Yukio Sakurai, Masaaki Nakamura, and Nobuyuki Kawase. "The Latest Frontiers of Bubble Columns and Slurry Bubble Columns. Effect of Oil Dispersion on Flow Characteristics in Bubble Column." KAGAKU KOGAKU RONBUNSHU 27, no. 4 (2001): 477–79. http://dx.doi.org/10.1252/kakoronbunshu.27.477.

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47

Ekambara, K., and M. T. Dhotre. "CFD simulation of bubble column." Nuclear Engineering and Design 240, no. 5 (May 2010): 963–69. http://dx.doi.org/10.1016/j.nucengdes.2010.01.016.

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Merchuk, JoséC, Sigal Ben-Zvi (Yona), and Keshavan Niranjan. "Why use bubble-column bioreactors?" Trends in Biotechnology 12, no. 12 (December 1994): 501–11. http://dx.doi.org/10.1016/0167-7799(94)90058-2.

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Ityokumbul, M. T., D. V. Ramani, and M. M. Kissel. "Fundamentals of Bubble Column Flocculation." Particulate Science and Technology 15, no. 2 (April 1997): 158. http://dx.doi.org/10.1080/02726359708906752.

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50

Yoshida, Fumitake. "Bubble column research in Japan." Chemical Engineering & Technology - CET 11, no. 1 (1988): 205–12. http://dx.doi.org/10.1002/ceat.270110128.

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Journal articles on the topic 'Bubble column'

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