| The power characteristic and mixing performance of powder mixing were studied in the standard elliptical bottom tank with diameter of 0.476m. Experiments used resign particles and glass bead particles as materials, through out changing the impeller, rotating speed and the filling level of powder material to investigate the power characteristic of powder mixing. And the correlated equation of power number were derived. We investigate the effect of the speed and filling level for the performance of powder mixture through out four screw belt type impeller’s powder mixing performance studying. We investigate the axial and radial cross section on powder mixing performance by ANOVA analysis method. We made a summary for the four paddle mixing performance and the quantitative description of each type of pitch for the environment.Experimental results show that stirring power is almost linear relationship with the changing of speed, in other words the value of the torque independent of the rotational speed for the powder system.The stirring power and torque values are increased with the increasing of the filling level. And for the same impeller, the rate of stirring power was significantly increased with increasing speed. Exploring the relationship between the P/N and the filling level, we found that they are almost linear relationship, but we found that the paddle is different, different scale factors. We found rotating speed and filling level are important parameters of the powder mixed by the erperiment of powder mixing. We found that the faster the speed, the shorter the mixing time required and we can achieve fast and efficient mixing with lower filling level. But the degree of influence of paddle is different, if the paddle can give strong shearing, the influence of filling level can be weaken. Through the four paddle mixing rate of quantitative calculation, we found out that the impeller IV mixing performance is the best, the impeller II mixing performance is the worst, and impeller I and III is at an intermediate level. So impeller IV can be Widely used in mixing the entire tank, and the first and the third paddle-type can be used in special environment. We indicate that the impeller I apply the environment which acquire lower speed near the wall and the impeller III apply the environment which acquire higher speed near the wall. This topic gives the results can be used as a guidance to develop appropriate ribbon powder mixing equipment. |
