This research examined the impact of various impeller shapes on the solid cloud volume within solid-liquid stirred vessels using Computational Fluid Dynamics (CFD) simulation techniques. Recent advancements highlight the importance of optimizing the geometry of impellers as they play a pivotal role in enhancing mixing performance across various industries, particularly within chemical and pharmaceutical sectors.
Stirred vessels are fundamental apparatuses used extensively for mixing solid and liquid materials. They facilitate numerous processes, including mass transfer, homogenization, and chemical reactions. The significance of solid-liquid mixing has surged due to its practical applications, and as such, studying the contribution of impeller designs to the overall mixing efficiency has gained much attention. This research stands out for its systematic approach, simulating 33 distinct impeller designs to determine their impact on solid cloud volume—an integral metric of mixing quality.
The methodology employed by the researchers combined the RNG k-ε model, recognized for turbulence simulation, and the Eulerian-Eulerian approach for representing multiphase flow dynamics effectively. One noteworthy outcome involved the pitched blade impeller with four 45-degree blades (PB-45d-4B), which exhibited significant potential for maximizing solid cloud volume. Results indicated this specific design facilitated superior mixing efficiency, achieving the highest occupied volume by solid cloud compared to other studied configurations.
Among the various configurations tested, alterations such as blade number adjustments and geometric modifications were explored. For example, changing the blade count of the PB-45d-3B impeller resulted in increasing the solid cloud volume up to 72% of vessel volume. Such findings underline the direct correlation between impeller shape or characteristics and solid-liquid mixing efficacy.
Notably, the researchers identified the enhancements obtained by incorporating additional features, such as adding vertical blades to the primary impeller structure and surrounding rings. These modifications not only improved the impeller’s performance but also highlighted the innovative design possibilities for achieving even greater mixing capabilities. The PB-45d-3B impeller with enhanced geometry achieved remarkable results, boasting solid cloud volumes up to 91.16% of the total vessel volume.
The results of this study provide valuable insights, establishing guidelines for selecting optimal impeller designs within solid-liquid stirred vessels. This research could significantly influence future design configurations and operational parameters for mixing processes, addressing key challenges faced within various industries, including pharmaceuticals, environmental engineering, and food processing.
Conclusively, the findings from this CFD simulation study present substantial advancements toward refining solid-liquid mixing methodologies. By fostering collaboration between innovative design practices and computational techniques, this research paves the way for future explorations aiming to push the boundaries of efficiency and effectiveness within stirred vessel operations.