Abstract
An improved second-order moment bubble-liquid two-phase turbulent model is developed to predict the hydrodynamic characteristics of the shallow bioreactor using two height-to-diameter ratios of H/D = 1.4 and H/D = 2.9. The two-phase hydrodynamic parameters, the bubble normal and shear stress, the bubble energy dissipation rate, the bubble turbulent kinetic energy, etc. were numerically simulated. These parameters increased along with flow direction and constituted a threat to cells living at far distance away from the gas jetting inlet regions, rather than a finding of higher cell damage at near the jetting inlet region, as reported by Babosa et al. 2003. A new correlation named the turbulent energy production of bubble-liquid two-phase flow was proposed to successfully verify this experimental observation. A smaller H/D ratio makes more contributions to the generation of lower turbulent energy productions, which are in favor of the alleviation of cell damage. The extremely long and narrow shape of the bioreactor is deteriorative for cell living.
Highlights
The shallow gas-liquid bioreactor characterized by the lower height-to-diameter ratios, has been widely applied in the field of biotechnology engineering, chemical engineering and pharmaceutical industries because of its low gas pressure drop, absence of moving parts, low cost and robust liquid phase residence time, especially eliminating the high-pressure drop of the tall reactors [1,2,3], Bubble-liquid hydrodynamics in the shallow reactor are predominantly controlled by sparger construction and the ratios of height to diameter (H/D), which are quietly different from those of a taller-shaped reactor
The purpose of this work is to analyze the effects of H/D ratios on bubble-liquid hydrodynamics, i.e., normal and shear stress of bubble flow, energy dissipation rate of bubble phase, turbulent kinetic energy of bubble flow and two-phase turbulent energy production values, etc
Discussion hydrodynamicparameters parameters ininassociation with cell culture solvedsolved by this by model the are
Summary
The shallow gas-liquid bioreactor characterized by the lower height-to-diameter ratios, has been widely applied in the field of biotechnology engineering, chemical engineering and pharmaceutical industries because of its low gas pressure drop, absence of moving parts, low cost and robust liquid phase residence time, especially eliminating the high-pressure drop of the tall reactors [1,2,3], Bubble-liquid hydrodynamics in the shallow reactor are predominantly controlled by sparger construction and the ratios of height to diameter (H/D), which are quietly different from those of a taller-shaped reactor. The complex mechanism of bubble-liquid two-phase turbulent hydrodynamics and the effects of sparger design and H/D ratios on flows and transport characteristics have not been acquainted clearly. Reasonable design and optimized strategies of the bioreactor are the key issues for successfully producing commercial biopharmaceuticals. Both the experimental and the simulation investigations have been focused on the effect of the height-to-diameter (H/D) ratios on the flow performance in the shallow bubble column reactor. Throat et al [9] investigated the combined effects
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
