CFD simulation of power characteristics and flow field distribution of different spiral stirring paddles.

• Stirring paddles with high Ls / S values have more potential for energy savings. • The number of blades has little effect on the power characteristics of stirring paddles with high Ls / S values. • Higher velocity flow field obtained by spiral stirring paddles. Stirred reactors are widely used in various industries, and the stirring paddle structure has a significant effect on its power consumption. Therefore, in this study, different spiral stirring paddles were investigated. The effects of the ratio of paddle length to leads (Ls / S) design values and number of blades on the power characteristics and internal flow field of the reactor are discussed in detail, and the correlation equation of power number (Np) concerning Re and Ls / S values is fitted. It was found that the Np of stirring paddles increased and then decreased as the Ls / S value increased, and the effect of the number of blades on the Np gradually reduced. When the Ls / S value is equal to 0.6, the high-speed region of the flow field is the largest and the mixing effect is the best. The conclusions obtained can provide a reference for the energy-saving optimal design of spiral stirring paddles. [ABSTRACT FROM AUTHOR]