Optimization of oxygen transfer and power consumption in aerobic bioprocess by designing disc turbine impeller based on CFD-Taguchi method

Abstract

Abstract Disc turbine impeller serves as a vital component of stirred-tank bioreactors and plays crucial role in optimizing their performance. This research integrates Computational Fluid Dynamics (CFD) with Taguchi experimental method to analyze the effects of blade curvature, asymmetry, and radial bending angles on disc turbine impeller performance. The designed P-0.1-T15B20-AM30° impeller maximizes the objective function $${E}_{V}$$ , balancing volumetric oxygen transfer coefficient $${k}_{L}a$$ and power input per unit volume $$P/V$$ . Statistical analysis revealed that blade curvature significantly affected $${k}_{L}a$$ and $$P/V$$ , blade asymmetry substantially impacted $$P/V$$ and $${E}_{V}$$ , and the radial bending angle exhibited a notable influence on $${k}_{L}a$$ , $$P/V$$ , and $${E}_{V}$$ . The P-0.1-T15B20-AM30° impeller sustains an average oxygen transfer efficiency of 52.3% equivalent to that of the Rushton turbine (RT) impeller and 68.9% akin to the CD-6 impeller, while its average energy consumption is merely 31.2% and 46.1% of the RT and CD-6 impellers, respectively. The average $${E}_{V}$$ of the P-0.1-T15B20-AM30° impeller is enhanced by 12.4% and 8% in comparison to the RT and CD-6 impellers, respectively. Conclusively, these results demonstrate that the P-0.1-T15B20-AM30° impeller offers economic and practical advantages in aerobic bioprocesses and presents new perspectives for advancing impeller design.

Keywords

• Aerobic bioprocess
• Computational fluid dynamics
• Disc turbine impeller
• Oxygen transfer
• Power consumption
• Taguchi method