Bioreactor Mixing: a Comparison of Computational Fluid Dynamics and Experimental Approaches in the Pursuit of Sustainable Bioprocessing for the Bioeconomy

Abstract

This paper highlights the importance of bioreactors in the bioeconomy, focusing on the role of mechanical mixing in promoting optimal conditions for microorganism growth and productivity. Computational fluid dynamics (CFD) simulations are increasingly used in bioreactor design to predict fluid dynamics and mixing characteristics. This study utilizes CFD simulations with OpenFOAM^® to predict the power number of various stirring devices in a lab-scale reactor. The torque and power number results of three different stirrers were compared through experimental and simulation methods. The pitched blade and cage impeller showed an increase in experimental torque and power number with rotational speed, while the paddle impeller had much higher experimental values than the simulated values at all speeds. The study demonstrates the value of CFD models for predicting bioreactor performance, despite some inaccuracies in simulations. These findings are important for industries seeking to optimize bioreactor design and increase productivity through better mixing processes.