Similarity analysis of size-induced segregation and flow behavior during the scaling up process of rotating drums

This study investigates the size-induced radial segregation of binary mixtures in different sized rotating drums. The results indicate that at a constant Froude number, the time to reach the stable segregation state increases with the drum size increasing, while the final particle segregation patterns remain similar. A correlation of the segregation rate as a function of scale-up ratio and Froude number is proposed, indicating that the segregation rate decreases with the drum size increasing. The similarity in particle velocity and particle-particle contact force is analyzed, showing that particle velocity distribution shows much difference in different sized drums at a low Froude number but less difference at a high Froude number. The average velocity increases with the drum size increasing. Contact force distribution shows significant difference at all Froude numbers, with the average force increasing with the drum size. Total power consumption per unit mass increases with the drum size increasing.