Listar por tema "Non-Newtonian"

In the present study bubble breakup and coalescence phenomena applied to non-newtonian fluids were simulated in order to characterize gas-liquid mass transfer in a 10 L bioreactor equipped with different impeller configurations. ...

Objectives: kL a mass transfer coefficient was predicted using CFD (computational fluid dynamics) for analyzing non-newtonian effects on gas liquid mass transfer in a 10 L bioreactor stirred with an Anchor Impeller. ...

Hydrodynamics Simulation of Different Impeller Geometries Applied to Non-Newtonian Fluids in A Stirred Tank Reactor
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Niño, Lilibeth | 2020-10

In the present study bubble breakup and coalescence phenomena applied to non-newtonian fluids were simulated in order to characterize gas-liquid mass transfer in a 10 L bioreactor equipped with different impeller configurations. The 𝒌𝑳𝒂 mass transfer coefficient was estimated based on hydrodynamics simulation. Four geometries are proposed for analyzing flow pattern effect on gas liquid mass-transfer: Anchor Impeller (Radial Flow Pattern), Helical Impeller (axial upwards pumping), Interference Turbine (axial upwards and downwards pumping) and High Efficiency Turbine (axial downwards pumping). It was found that radial velocity flow patterns maximize 𝒌𝑳𝒂 as a consequence of its great capacity to break bubbles in Non-Newtonian fluids. The latter is confirmed by the highest 𝒌𝑳𝒂 values simulated using the Anchor Impeller. Also, it was found that pumping flow direction influences air dispersion: axial downwards pumping of High Efficiency Turbine generates better results in comparison to axial downwards pumping geometries (Helical Impeller). Motivated by results found on this work, the main criteria to design a device for improving of 𝒌𝑳𝒂 mass transfer in nonNewtonian applications are: (a) generating of radial, axial pumping down and shear velocities; (b) generating of small bubbles, and (c) generating of wall shear stress, lower than critical values reported according to references.

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Non-Newtonian Behavior Effect on Gas-liquid Mass Transfer using an Anchor Impeller for CSTR Bioreactors: A CFD Approach
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Niño, Lilibeth | 2018-11

Objectives: kL a mass transfer coefficient was predicted using CFD (computational fluid dynamics) for analyzing non-newtonian effects on gas liquid mass transfer in a 10 L bioreactor stirred with an Anchor Impeller. Methods/Statistical Analysis: The set up bioreactor configurations were defined by typical culturing conditions used for fungi organism. Bubble breakage frequency and coalescence rate were simulated using Luo - Colaloglou and Tavlarides models and PBM approaches, respectively. Simulated results from different shear rates due to non-newtonian behaviour are compared by analyzing its influences in bubble size and power input. Findings: A clear relationship between high levels of shear rates and small bubble sizes is found in this work. The later is also associated with the high values of kL a simulated (270 h-1) and compared to levels found at low shear rates (62 h-1). Application/Improvements: Impressed by these findings new design optimizations for non-newtonian bioprocessing applications would be improved using CFD.

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Listar por tema "Non-Newtonian"

Hydrodynamics Simulation of Different Impeller Geometries Applied to Non-Newtonian Fluids in A Stirred Tank Reactor

Non-Newtonian Behavior Effect on Gas-liquid Mass Transfer using an Anchor Impeller for CSTR Bioreactors: A CFD Approach

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Hydrodynamics Simulation of Different Impeller Geometries Applied to Non-Newtonian Fluids in A Stirred Tank Reactor

Non-Newtonian Behavior Effect on Gas-liquid Mass Transfer using an Anchor Impeller for CSTR Bioreactors: A CFD Approach

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Listar por tema "Non-Newtonian"

Hydrodynamics Simulation of Different Impeller Geometries Applied to Non-Newtonian Fluids in A Stirred Tank Reactor ﻿

Non-Newtonian Behavior Effect on Gas-liquid Mass Transfer using an Anchor Impeller for CSTR Bioreactors: A CFD Approach ﻿

Envíos recientes

Hydrodynamics Simulation of Different Impeller Geometries Applied to Non-Newtonian Fluids in A Stirred Tank Reactor

Non-Newtonian Behavior Effect on Gas-liquid Mass Transfer using an Anchor Impeller for CSTR Bioreactors: A CFD Approach

Portales Institucionales

Hydrodynamics Simulation of Different Impeller Geometries Applied to Non-Newtonian Fluids in A Stirred Tank Reactor

Non-Newtonian Behavior Effect on Gas-liquid Mass Transfer using an Anchor Impeller for CSTR Bioreactors: A CFD Approach