Results 211 to 220 of about 29,708 (266)

Drag-force regimes in granular impact

Physical Review E, 2014
We study the penetration dynamics of a projectile incident normally on a substrate comprising of smaller granular particles in three-dimensions using the discrete element method. Scaling of the penetration depth is consistent with experimental observations for small velocity impacts.
Mukesh, Tiwari, T R Krishna, Mohan, Surajit, Sen   +2 more
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A note on the diffusion drag forces

The Bulletin of Mathematical Biophysics, 1949
A formal derivation of the expression for the diffusion drag force is given. The expression involves the coefficient of diffusion of the solute through the solvent and the coefficient of diffusion which the solute would posses if it diffused through itself in the form of a gas, in the absence of the solvent.
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Ion Drag Force in Collisional Plasmas

IEEE Transactions on Plasma Science, 2009
A simple hydrodynamic model is used to calculate the ion drag force acting on a small grain in highly collisional weakly anisotropic plasma. First, it is shown that as long as the grain does not absorb ions on its surface, the result from this model coincides with the highly collisional limit of the more general kinetic approach proposed by Ivlev et al.
Khrapak, S., Chaudhuri, M., Morfill, G.
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Ion drag force in complex plasmas

Physical Review E, 2002
The problem of calculating the ion drag force in complex plasmas is considered. It is shown that the standard theory of Coulomb scattering usually fails for the ion-dust elastic collisions. A simple approach to extend this theory is proposed. This leads to a considerable enhancement in the ion-dust elastic scattering cross section and, hence, increases
Khrapak, S., Ivlev, A., Morfill, G., Thomas, H.   +3 more
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Drag forces of porous-medium acoustics

Physical Review B, 1993
The drag forces controlling the amount of relative flow induced in a fluid-saturated porous material by a mechanical wave are modeled here from first principles. Specifically, analytical expressions for the drag are derived for material models that possess variable-width pores; i.e., pores that have widths that vary with distance along their axis.
, Pride, , Morgan, , Gangi
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Drag force and clustering in bubble swarms

AIChE Journal, 2012
In this article, results of detailed numerical simulations are reported meant to provide a closure relation for the drag force acting on bubbles rising in a dense swarm. The formation of clusters of bubbles in a periodic domain and the effect thereof on the rise velocity and effective drag coefficient on the bubbles are studied.
Roghair, I., Sint Annaland, van, M., Kuipers, J.A.M.   +2 more
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Drag Force, Drag Torque, and Magnus Force Coefficients of Rotating Spherical Particle Moving in Fluid

Particulate Science and Technology, 2012
The mutual influence of translational and rotational spherical particle movements in calm water was studied using experimental data and numerical simulation. Spherical balls with a density close to that of water were speeded up in special devices, which ensured the required ball rotational and translational velocity in the given plane.
Lukerchenko, N. (Nikolay), Kvurt, Y., Keita, I. (Ibrahima), Chára, Z. (Zdeněk), Vlasák, P. (Pavel)   +4 more
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Normal force and drag force in magnetorheological finishing

SPIE Proceedings, 2009
The material removal in magnetorheological finishing (MRF) is known to be controlled by shear stress, λ, which equals drag force, F d , divided by spot area, As. However, it is unclear how the normal force, F n , affects the material removal in MRF and how the measured ratio of drag force to normal force F d / F n , equivalent to ...
Chunlin Miao, Shai N. Shafrir, John C. Lambropoulos, Stephen D. Jacobs   +3 more
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Nonlinear drag force in dusty plasmas

Physics of Plasmas, 2005
The condition for large angle scattering in ion-grain collisions, which determine the nonlinear part of the ion drag force, coincides with the condition for the grain screening to be nonlinear (∣eϕ∣∕Ti>1 where ϕ is the electrostatic grain potential and Ti is the ion mean energy), a condition met in many laboratory experiments.
V. N. TSYTOVICH, DE ANGELIS, UMBERTO, A. V. IVLEV, G. E. MORFILL, S. A. KHRAPAK   +4 more
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The drag force on a moving dislocation, I. Zero temperature (lattice drag force)

Journal of Applied Physics, 1979
The kinematics and equations of motion of an equivalent single-degree-of-freedom system for a moving dislocation in a modified Frenkel-Kontorova linear-chain model are derived and then used in conjunction with computer simulation runs. The average drag force on a moving dislocation at zero temperature (lattice drag force) is computed for a range of ...
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