Global ETD Search
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Showing 1 to 14 of 14 for “"liquid holdup"”.
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Pressure drop, liquid holdup and mass transfer in a graphite fibre bed with upward co-current gas-liquid flow
The pressure drop, liquid holdup and overall mass transfer capacity have been studied in a graphite fibre electrode of porosity 0.90and fibre diameter 22 micrometer with cocurrent upward gas-liquid flow. A U-tube mercury manometer was used to measure the pressure drop in a graphite fibre bed 356 mm …
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The prediction of flow patterns, liquid holdup and pressure losses occurring during continuous two-phase flow in horizontal pipelines
… of "quick closing" valves by means of which the liquid holdup was measured. Transparent nipples were placed at two points in the two inch line and at three points in the four inch line. Through these nipples the flow patterns were photographed. Pressure taps were located at fourteen points in …
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Hydrodynamics of trickle bed reactors (TBRS) packed with industrial catalyst using advanced measurement techniques
… improvements in the phase distribution, liquid holdup profile, and catalyst utilization efficiency. In the pilot plant scale reactor, the catalyst shape showed a significant impact on the hydrodynamics, pressure drop, local gas and liquid velocities, and flow regime transition. The …
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The effect of flow regimes in the distillation of systems containing two liquid phases
… to exhibit foaminess near a single to two liquid phase boundary. It was seen, in a sintered plate column under mass transfer conditions, that distillation systems where the liquid appeared as one phase in one part of a column and two phases in another part, exhibited foaminess when the …
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Integrated multiphase flow modeling in wellbore for downhole pressure predictions
… by incorporating the state-of-the-art onset of liquid loading model. Unlike the existing models, the new model classifies the flow based on the onset of liquid loading. If liquid loading occurs, then the model uses a sophisticated drift-flux model which proved to be both simple and relatively …
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Hydrodynamics Of Trickle Bed Reactors: Measurements And Modeling
… has been performed to examine the quality of liquid phase distribution in a high pressure system. The results were provided in terms of distribution of the effluent liquid fluxes and cross-sectional liquid holdups. Their individual trends, but also their relation with respect to operating …
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Studies of multiphase distribution and flow in bubble/ slurry bubble columns with /without internals and advanced sustainable construction materials using sophisticated measurement techniques
… and employed to study line-averaged three-phase holdup distribution in a Slurry Bubble Column Reactor (SBCR) using gamma-ray densitometry (GRD) and point optical fiber probe (OFP) techniques. The obtained results indicated that increasing the solids loading increased the solid holdup and …
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Experimental and modeling studies using packed bed reactors: Liquid phase ethylene production by hydrogenation of acetylene
… as to increase the selectivity and conversion, liquid-phase hydrogenation of acetylene was investigated in packed bed reactors (PBR) using a commercial catalyst. The reactor performance of two-phase flow PBRs was assessed experimentally complemented by a validated mathematical model at different …
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Hydrogen-water isotope exchange in a trickle bed column by process simulation and 3D computational fluid dynamics modelling
… separation methods of hydrogen isotopes, H2-H2O liquid catalytic exchange has attracted interest because of its mild operating conditions, high efficiency, limited corrosion and toxicity. The method of hydrogen-water liquid catalytic exchange has many possible applications such as; producing and …
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Computer control of chemical process plants with special reference to distillation
… A dynamic simulation of the column with a binary liquid system has been compiled using deterministic models that include fluid dynamics via Brambilla's equation for tray liquid holdup calculations. The simulation predictions have been tested experimentally under steady-state and transient …
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Experimental characterisation of bubbly flow using MRI
… drift-flux analysis is suitable for predicting liquid holdup in electrolyte stabilised systems, it does not provide an accurate representation of hydrodynamic stability. Finally, velocity encoded spiral imaging was applied to study the dynamics of single bubble wakes. Both freely rising bubbles …
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A study of Taylor bubbles in vertical and inclined slug flow using multiphase CFD with level set
… to predict integral flow parameters such as liquid holdup (or void fraction) and pressure gradient. These closure relations are typically developed either empirically or from semi-empirical models assuming idealized geometry of the interface, thus they carry the highest uncertainties in the …
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Investigation of Multiphase Reactor Hydrodynamics Using Magnetic Resonance Imaging
… vessels are considered: a co-current upflow gas-liquid-solid bed, a co-current downward trickle bed (gas, liquid, solid), and a gas-solid fluidised bed. These reactors were selected as they commonly demonstrate local hydrodynamic anisotropy which affects the global performance of industrial …
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Multiphase flow modeling and deposition of hydrates in oil and gas pipelines
… A first pass model for the slip between gas and liquid phases, using dimensionless numbers, was developed for a general fluid system. The effect of inclination/gravity was studied and incorporated in the gas-liquid slip. Using this model to simulate hydrate formation in subsea pipelines, it was …