Inertial effects on non-spherical particle rotation on turbulent channel flow etc15 Tracking Number 40Presentation: Session: Multiphase and non-Newtonian flows 2 Room: Room D Session start: 10:30 Thu 27 Aug 2015 Helge I. Andersson helge.i.andersson@ntnu.no Affifliation: Norwegian University of Science and Technology Lihao Zhao lihao.zhao@ntnu.no Affifliation: Norwegian University of Science and Technology Niranjan R. Challabotla niranjan.r.challabotla@ntnu.no Affifliation: Norwegian University of Science and Technology Evan A. Variano variano@berkeley.edu Affifliation: University of California Berkeley Topics: - Turbulence in multiphase and non-Newtonian flows Abstract: We investigated the rotation of non-spherical particles (rod-like and disk-like) in turbulent channel flow with focus on inertial effects. A direct numerical simulation (DNS) with an Eulerian-Lagrangian approach was performed. A wide range of particle aspect ratios, λ, ranging from 0.01 to 50 were considered for Stokes numbers St equal to 1 and 30. In the particle reference frame, statistical results reveal the importance of shape effect on the particle rotation. The rods (λ > 1) are spinning (rotation about their symmetry axis) more than tumbling (rotation about other axes) whereas disks (λ < 1) behave oppositely. With increasing particle inertia, i.e. higher St, the preferential tumbling of the disks and the spinning of the rods are reduced. We ascribe these observations to the varying degree of alignment of the particle symmetry axis with the fluid vorticity vector. |