TY - JOUR
T1 - Numerical simulations of granular materials flow around obstacles
T2 - The role of the interstitial gas
AU - Levy, Avi
AU - Sayed, Mohamed
N1 - Funding Information:
The financial support of the Climate Change Action Plan (CCAP) 2000, through the project on Granular Multiphase Flow is gratefully acknowledged.
PY - 2007/1/1
Y1 - 2007/1/1
N2 - A two-fluid model was used to determine the influence of the gas phase on granular flow interaction with obstacles. The governing equations of two-dimensional, two-phase flow were solved numerically using a finite-volume-based numerical code. The numerical results are qualitatively compared to experimental observations from various sources, and good agreement is found. Several cases were tested in order to examine the role of the velocities of both phases, solid volume fraction, particle diameter, and gravity. The results show that under certain conditions, particularly for dilute flows, a bow granular shock wave clearly forms in the front of the obstacle. Alternatively, for dense flows, granular shock waves were not observed. Based on the present observations, it appears that the formation and the shape of the bow granular shock wave are influenced by the interaction between the solid and gas phases and the gravity force. The results indicate that the common assumptions of neglecting both the gravity and the influence of the gas phase on the granular flow, may be appropriate only in the vicinity of the obstacle, where granular creeping flow takes place.
AB - A two-fluid model was used to determine the influence of the gas phase on granular flow interaction with obstacles. The governing equations of two-dimensional, two-phase flow were solved numerically using a finite-volume-based numerical code. The numerical results are qualitatively compared to experimental observations from various sources, and good agreement is found. Several cases were tested in order to examine the role of the velocities of both phases, solid volume fraction, particle diameter, and gravity. The results show that under certain conditions, particularly for dilute flows, a bow granular shock wave clearly forms in the front of the obstacle. Alternatively, for dense flows, granular shock waves were not observed. Based on the present observations, it appears that the formation and the shape of the bow granular shock wave are influenced by the interaction between the solid and gas phases and the gravity force. The results indicate that the common assumptions of neglecting both the gravity and the influence of the gas phase on the granular flow, may be appropriate only in the vicinity of the obstacle, where granular creeping flow takes place.
UR - http://www.scopus.com/inward/record.url?scp=33847631219&partnerID=8YFLogxK
U2 - 10.1063/1.2674831
DO - 10.1063/1.2674831
M3 - Article
AN - SCOPUS:33847631219
SN - 1070-6631
VL - 19
JO - Physics of Fluids
JF - Physics of Fluids
IS - 2
M1 - 023302
ER -