title: Computational fluid dynamics modeling of gas dispersion in multi impeller bioreactor.
abstract: In the present study, experiments have been carried out to identify various flow regimes in a dual Rushton turbines stirred bioreactor for different gas flow rates and impeller speeds. The hydrodynamic parameters like fractional gas hold-up, power consumption and mixing time have been measured. A two fluid model along with MUSIG model to handle polydispersed gas flow has been implemented to predict the various flow regimes and hydrodynamic parameters in the dual turbines stirred bioreactor. The computational model has been mapped on commercial solver ANSYS CFX. The flow regimes predicted by numerical simulations are validated with the experimental results. The present model has successfully captured the flow regimes as observed during experiments. The measured gross flow characteristics like fractional gas hold-up, and mixing time have been compared with numerical simulations. Also the effect of gas flow rate and impeller speed on gas hold-up and power consumption have been investigated.
authors.affiliation: Biotechnology Division, National Institute for Interdisciplinary Science and Technology (CSIR), Trivandrum-695 019, India.
authors.forename: Syed Ubaid
authors.initials: SU
authors.lastname: Ahmed
authors.forename: Panneerselvam
authors.initials: P
authors.lastname: Ranganathan
authors.forename: Ashok
authors.initials: A
authors.lastname: Pandey
authors.forename: Savithri
authors.initials: S
authors.lastname: Sivaraman
mesh_terms: D019149:Bioreactors; D003198:Computer Simulation; D005740:Gases; D008956:Models, Chemical
chemical_list: D005740:Gases