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Showing 1 to 20 of 22 for “"GAS-LIQUID FLOW"”.
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Nonlinear long-wave interfacial stability of two-layer gas-liquid flow
The flow of two immiscible viscous fluids in a thin inclined channel is considered, in either a cocurrent or countercurrent regime. Following the air-water case, which is found in a variety of engineering systems, we allow the upper fluid to be either compressible or incompressible. The disparity …
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Homogeneous Catalysis in Flow-by Porous Electrodes Containing Gas-Liquid Flow (Mass Transfer, Redox Catalyst, Oxygen Electrode)
… and reaction in a porous electrode containing gas-liquid flow and a dissolved catalyst were studied. Dimensionless criteria were developed for the selection and evaluation of candidate catalysts.
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Development of an optimised integrated underbalanced drilling strategy for cuttings transport in gas-liquid flow through wellbore annuli.
Although understanding the relationship between gas-liquid two-phase fluid flows and the effects of the major drilling variables is critical to optimising underbalanced drilling (UBD) operations, to date, this has been an area of limited research and knowledge. This study contributes to the limited …
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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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Computational Modeling and Simulations of Hydrodynamics for Air-Water External Loop Airlift Reactors
… used for biochemical applications such as syngas fermentation and wastewater treatment. To further understand the inherent gas-liquid flow physics within the reactors, computational modeling and simulations of hydrodynamics for air-water external loop airlift reactors were investigated. The …
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Simulation of time-dependent free surface Navier-Stokes flows
… of time-dependent free-surface Navier-Stokes flows are developed. Both techniques are based on semi-implicit time advancement of the momentum equations, integral formulation of the spatial problem at each timestep, and spectral-element discretization to solve the resulting integral equation. …
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Hydro-pneumatic conveying of liquid by means of an airlift pump
Airlift pumps operating in two-phase gas-liquid flow are investigated with a view to establishing an analytical technique to aid in theoretically modelling air-lift pump behaviour. Extensive work on two test facilities constructed at the University of Cape Town's Hydrotransport Research facility …
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Annular Flow in a Low - Pressure Steam - Water System
<p>Two-phase annular flow is an important aspect of two- phase flow. Three different models, Ghosal, Wallis, and Levy models, were used to calculate the pressure drop in an nular two-phase flow. The calculated pressure drop was com pared with a set of experimental data. The pressure range of the …
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Cuttings transport and hydraulics optimisation for underbalanced drilling (UBD) operations in concentric and eccentric, directional and extended reach wells.
… drilling technology. However, this involves the flow of multiphase fluids, which introduces additional complexities due to highly transient flow patterns, unpredictable wellbore hydraulics and increased tendency for the settling of drilled cuttings in the wellbore. An accurate prediction of fluid …
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Caracterização experimental da separação gás-líquido em uma junção do tipo T inclinada
The two-phase flows at a T-Junction is a common feature in many industrial processes, such as oil field flow lines, pipeline networks and refinery streams to divide or combine flows. When a gas-liquid mixture flows through a junction, the phases can be separated unevenly such that the qualities in …
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Computational fluid dynamics modelling of dissolved oxygen in oxidation ditches.
… ditch, by taking into account two-phase gas-liquid flow, inter- phase oxygen mass transfer and dissolved oxygen. The main contributions to knowledge are the effect of bubble size distribution (BSD) and biochemical oxygen demand (BOD) distribution on the DO distribution. Species transport …
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Two-Phase Flow Measurement using Fast X-ray Line Detector System
… and heat and mass transfer mechanisms in various gas-liquid flow systems. It becomes critically important to accurately measure void fraction as advanced high fidelity two-phase flow models require high-quality validation data. However, void fraction measurement remains a challenging task to date …
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Flow patterns on sieve trays
Studies into gas-liquid flow patterns were carried out on commercial scale sieve trays where the ratio of froth depth to flow path length is typical of that found in practice. Experiments were conducted on a 2.44 m diameter air-water distillation simulator, in which flow patterns were investigated …
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Use of computational fluid dynamics in the design of bubble column reactors
… that depict the transport of discrete phases (gas bubbles or solid particles) and model biochemical reactions in a bubble column reactor are discussed here. The mixture model was used to calculate gas-liquid, solid-liquid and gasliquid-solid interactions. Multiphase flow is a difficult …
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Packed bed reactors at the pellet scale: magnetic resonance studies of hydrodynamics, mass transport and reaction
… use of packed bed reactors in industry, the flow, transport, and reaction phenomena occurring at the scale of individual catalyst pellets is poorly understood due to a lack of experimental techniques capable of non-invasively probing these phenomena at the pellet scale. This thesis presents …
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Gas lift optimization and flow instability
Gas lift is an artificial lift method used in the oil industry to lift reservoir fluid to the surface, by supplementing the reservoir pressure when it is depleted or insufficient. During oil production, this method can be affected by two-phase (gas-liquid) flow instability within the production …
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Agitation, mixing and mass transfer in simulated high viscosity fermentation broths
Gas-liquid mass transfer, agitator power consumption, rheology, gas-liquid mixing and gas hold-up have been studied in an agitated, sparged vessel of diameter, T = 0.3 m, with a liquid capacity of 0.02 m\(^3\), unaerated liquid height = 0.3 m. The solutions of sodium carboxymethylcellulose used …
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Development and application of Lattice Boltzmann and accurate volume of fluid numerical techniques on graphics processing units
… techniques for high density ratio two-phase flow as encountered in air conditioning and refrigeration equipment. In this research work, we have examined mesoscopic and macroscopic approaches of CFD modeling for multiphase calculations. We have examined two variants of two-phase Lattice …
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Rapid on-demand polymerization for multifunctional materials
… functionality are investigated. Segmented gas-liquid flow is used to deliver self-healing reagents through internal microvasculature to large-scale damage, leading to improvements in mixing and healing performance compared to alternative delivery strategies. Although the microvascular …
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Development of Micro to Milli-Scale Multiphase Reactors with and Without Solids for Integration Into Mini-Monoplants
… the first, the impact of fluids (CO₂(g), water) flow rates, channel geometry, and presence of surfactant (ethanol) on the resulting gas-liquid flow regime (bubble, bubble/slug, annular), pressure drop and interphase mass transfer coefficient (𝑘𝑙𝑎) are investigated. Here, the interphase mass …
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