(224c) Effect of Baffles on the Rate of Heat Transfer in Rotating Drums

Authors: 
Yohannes, B., Rutgers University
Cuitino, A. M., Rutgers University
Glasser, B., Rutgers University
Borghard, W. G., Rutgers University
Muzzio, F. J., Rutgers University
Kim, C., Rutgers University
Rotating drums are one of the most common devices used for industrial processes that involve thermal treatment of granular materials, such as drying and calcination. Adding baffles/lifters in the rotating drums is one of the approaches used to enhance the time required to heat the particles and improve the uniformity of the final product. The effect of the baffles on the heat transfer depends on the shape, the size, and number of baffles. We use discrete element method (DEM) simulations, in order to investigate the effect of baffles on heat transfer of granular materials in rotating drums. The simulations and analysis are limited to conductive heat transfer mechanism. We investigated the effect of baffles by changing the operating conditions, such as the fill level, speed of rotation, and baffle size and thermal properties of the particles and the drum. We found that the increase in the rate of heat transfer is directly related to the size and number of baffles. Particularly, we investigated the effect of baffles on the scale up of heat transfer based on the recent model developed by Yohannes et al (2016)* for granular flows in rotating drum with no baffles. We found that the scale up equation can be modified to account for the presence of baffles. In this talk, we will present results from our simulations and comparison of the results to prior models and experimental results. *B. Yohannes, H. Emady, K. Anderson, I. Paredes, M. Javed, W. Borghard, F. J. Muzzio, B. J. Glasser, and A. M. Cuitiño (2016), Physical Review E 94(4) 042902.