Development and evaluation of mixing mechanism of new transformable multiple impeller (AM impeller)

The axial flow in the vessel was the most critical flow under the laminar region, where the Reynolds number was less than 10. The most popular impeller which generates the axial flow is a helical ribbon impeller, but the production cost is high. By combining some pitched blade impellers, authors developed a new impeller, the production cost is lower than that of the helical ribbon. The mixing performance was investigated in laminar region. The new impeller had the same mixing performance as a helical ribbon. The partial helical ribbon type has a down flow that originates from two locations and intersects twice near the mixing shaft, and the four-stage pitched paddle type has two cylindrical down flows. AM impeller is not affected by the shaft, and it is considered to exhibit high mixing performance. The phase angle of the blades caused these characteristics of down flows of the AM impeller.