Abstract
The isolated mixed region (IMR) is gradually formed during stirring and reduces the mixing efficiency. The unsteady-state formation process of the IMR was modeled and its formation mechanism was analyzed. The rotating frequency of the impeller was optimized using the chaos mathematical theory to improve the stirring efficiency without increasing the power consumption. The calculated results demonstrate that the IMR is a coherent structure, and its formation process is based on the free shear effect of the mixed layer. The chaotic stirring method can accelerate the momentum dissipation process by 37% by eliminating the IMR, and increase the speed by up to 31%. Therefore, chaotic mixing can eliminate the IMR in a shorter time and lower the power consumption.
Funding source: National Natural Science Foundation of China
Award Identifier / Grant number: 51666006
Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: This research was supported by the National Natural Science Foundation of China (51666006).
Conflict of interest statement: The authors declare no conflicts of interest regarding this article.
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