Flow field analysis and design optimization strategies for double‐layer dislocated‐punched impellers

Abstract Mixing efficiency is a critical metric for evaluating the performance of biochemical reactors, as it directly influences both the mixing rate and energy consumption. To optimize mixing efficiency and mitigate energy dissipation during agitation, a novel dislocated‐punched Rushton impeller is proposed, integrating an offset blade arrangement with perforations. This study investigates the flow field characteristics and structural optimization of a double‐layer dislocated‐punched Rushton impeller. Initially, the flow field under varying conditions is analyzed to determine the optimal installation position and aperture size of the punched holes. Using multiple linear regression, the relationship between power and hole location is examined, facilitating the structural optimization of the impeller. The mixing efficiency of the optimized double‐layer dislocated‐punched Rushton impeller is evaluated and compared with that of conventional double‐layer Rushton and double‐layer dislocated‐blade impeller. Experimental results demonstrate that the double‐layer dislocated‐punched Rushton impeller reduces power by 14.63% and 19.77% compared to conventional designs and dislocated‐blade Rushton impeller, while enhancing mixing efficiency by 32% and 25.7%, respectively. For optimal performance, the punched holes should be evenly distributed across the impeller blades to maximize the effectiveness of the punched‐hole design. Further research has found that misaligned flow impellers can reduce the area of viscous regions and increase the distribution of shear strain rates when mixing viscous liquids.