Granular dynamics in a vertical bladed mixer: Secondary flow patterns

摘要: Abstract This article deals with numerical simulations and experimental measurements of the granular mixing process in a vertical cylindrical mixer two opposed flat blades 45° rake angle. The computer were conducted via discrete element method. recorded by color high-speed camera. Both approaches describe same way significant agreement observations. Even though geometry operating conditions are simple, dynamics system is often very complex variety flow structures can be created. For that reason, behavior individual flows patterns was analyzed discussed. effect centrifugal force on deformation free level material formation empty spaces behind stirrer described. In addition, particles specific regions characterized. At low rotational speed blades, tend to move close bottom vessel blade towards shaft. high values, moving exact opposite direction. Described movements near base create secondary form recirculation zones. Presence during also confirmed measurements. Based acquired knowledge, competing mechanisms presented: (i) different contact time blade; (ii) magnitude inertial forces acting around blade.