Abstract
| Original language | English |
|---|---|
| Pages (from-to) | 062203-1/10 |
| Number of pages | 10 |
| Journal | Physical Review E |
| Volume | 90 |
| DOIs | |
| Publication status | Published - 2014 |
Fingerprint
Cite this
}
Numerical investigation of the vertical plunging force of a spherical intruder into a prefluidized granular bed. / Xu, Y.; Padding, J.T.; Kuipers, J.A.M.
In: Physical Review E, Vol. 90, 2014, p. 062203-1/10.Research output: Contribution to journal › Article › Academic › peer-review
TY - JOUR
T1 - Numerical investigation of the vertical plunging force of a spherical intruder into a prefluidized granular bed
AU - Xu, Y.
AU - Padding, J.T.
AU - Kuipers, J.A.M.
PY - 2014
Y1 - 2014
N2 - The plunging of a large intruder sphere into a prefluidized granular bed with various constant velocities and various sphere diameters is investigated using a state-of-the-art hybrid discrete particle and immersed boundary method, in which both the gas-induced drag force and the contact force exerted on the intruder can be investigated separately. We investigate low velocities, where velocity dependent effects first begin to appear. The results show a concave-to-convex dependence of the plunging force as a function of intruder depth. In the concave region the force fits to a power law with an exponent around 1.3, which is in good agreement with existing experimental observations. Our simulation results further show that the force exerted on the frontal hemisphere of the intruder is dominant. At larger intruder velocities, friction with the granular medium causes a velocity-dependent drag force. As long as the granular particles have not yet closed the gap behind the intruder, this drag force is independent of the actual intruder depth. In this regime, the drag force experienced by intruders of different diameter moving at different velocities all fall onto a single master curve if plotted against the Reynolds number, using a single value for the effective viscosity of the granular medium. This master curve corresponds well to the Schiller-Naumann correlation for the drag force between a sphere and a Newtonian fluid. After the gap behind the intruder has closed, the drag force increases not only with velocity but also with depth. We attribute this to the effect of increasing hydrostatic particle pressure in the granular medium, leading to an increase in effective viscosity.
AB - The plunging of a large intruder sphere into a prefluidized granular bed with various constant velocities and various sphere diameters is investigated using a state-of-the-art hybrid discrete particle and immersed boundary method, in which both the gas-induced drag force and the contact force exerted on the intruder can be investigated separately. We investigate low velocities, where velocity dependent effects first begin to appear. The results show a concave-to-convex dependence of the plunging force as a function of intruder depth. In the concave region the force fits to a power law with an exponent around 1.3, which is in good agreement with existing experimental observations. Our simulation results further show that the force exerted on the frontal hemisphere of the intruder is dominant. At larger intruder velocities, friction with the granular medium causes a velocity-dependent drag force. As long as the granular particles have not yet closed the gap behind the intruder, this drag force is independent of the actual intruder depth. In this regime, the drag force experienced by intruders of different diameter moving at different velocities all fall onto a single master curve if plotted against the Reynolds number, using a single value for the effective viscosity of the granular medium. This master curve corresponds well to the Schiller-Naumann correlation for the drag force between a sphere and a Newtonian fluid. After the gap behind the intruder has closed, the drag force increases not only with velocity but also with depth. We attribute this to the effect of increasing hydrostatic particle pressure in the granular medium, leading to an increase in effective viscosity.
U2 - 10.1103/PhysRevE.90.062203
DO - 10.1103/PhysRevE.90.062203
M3 - Article
C2 - 25615081
VL - 90
SP - 062203-1/10
JO - Physical Review E
JF - Physical Review E
SN - 1539-3755
ER -