THE INFLUENCE OF OPERATING PARAMETERS ON THE TEMPERATURE DISTRIBUTION IN FLIGHTED ROTARY DRUMS
Rotary drums are used in many industrial applications for heat and mass transfer between gas and solid particles. Additional flights are installed to improve the mixing of adhesive products and especially to increase the exchange surface between gas and solids. The flights are mounted on the inside of the drum and lift particles out of the solid bed to shower them as curtains in the passing gas phase of the drum, where heat and mass transfer is very intense. The amount of particles and their distribution are influenced by operating parameters (rotational speed, filling degree, air volume flow), which were researched in a previous study about transverse particle motion. In order to couple the transverse particle motion to the heat transfer, heat transfer experiments were carried out. Therefore, an indirectly heated flighted rotary drum was designed and constructed. Batch experiments, which were divided into heating and cooling process, with glass beads as reference material were performed. The temperature distribution inside the drum was measured using thermocouples at different axial and radial positions in the cylindrical drum. The operating parameters rotational speed, filling degree and air volume flow were varied to investigate their influence on the temperature distribution inside the drum. It was found that increasing the rotational speed as well as the air volume flow leads to faster changing temperatures. Meanwhile, increasing the filling degree results in slower temperature drop rates.