There have been many attempts to derive continuum models for dense granular flow, but a general theory is still lacking. Here, we start with Mohr-Coulomb plasticity for quasi-two-dimensional granular materials to calculate (average) stresses and slip planes, but we propose a "stochastic flow rule" (SFR) to replace the principle of coaxiality in classical plasticity. The SFR takes into account t...

In this paper, we investigate the effects of slip condition, transverse magnetic field and radiative heat transfer to unsteady flow of a conducting optically thin fluid through a channel filled with porous medium. Exact solution of the governing equations for fully developed flow is obtained in closed form. Detailed computations of the influence of the Grashof number, Hartmann number, slip para...

A series of experiments are presented which study the flow kinematics of water past drag-reducing superhydrophobic surfaces. The ultrahydrophobic surfaces are fabricated from silicon wafers using photolithography and are designed to incorporate precise patterns of micrometer-sized ridges aligned in the flow direction. The ridges are made hydrophobic through a chemical reaction with an organosil...

We intend to study a particle fluid suspension model for blood flow through an axially asymmetric but radially symmetric mild stenosis in the annular region of an inclined tapered artery and a co-axial catheter in a suitable flow geometry has been considered to investigate the influence of velocity slip at the stenotic wall as well as hematocrit, shape parameter. The model also includes the tap...

Internal recirculation in a moving droplet, enforced by the presence of fluid–fluid interfaces, plays an important role in several droplet-based microfluidic devices as it could enhance mixing, heat transfer, and chemical reaction. The effect of slip on droplet circulation is studied for two canonical steady-state problems: two-phase Couette, boundary-driven, and Poiseuille, pressure/body force...

The development of rotor flow associated with mountain lee waves is investigated through a series of highresolution simulations with the nonhydrostatic Coupled Ocean–Atmospheric Mesoscale Prediction System (COAMPS) model using free-slip and no-slip lower boundary conditions. Kinematic considerations suggest that boundary layer separation is a prerequisite for rotor formation. The numerical simu...

Highly filled polymeric suspensions, such as those involved in Powder Injection Moulding (PIM), exhibit complex rheological behaviour. A detailed understanding of the rheology of these suspensions is prerequisite for their optimum and safe processing. In present paper, rheological behaviour of highly filled WC-Co compounds during capillary flow was studied with emphasis on apparent slip. Contri...

A mathematical model is developed to study the MHD oscillatory blood flow through stenosed artery under the effect of slip velocity. The blood is assumed to be Newtonian. Analytical expressions for velocity profile, flow rate, wall shear stress and resistive impedance have been obtained. These expressions are computed numerically and the computational results are presented graphically. It is no...

In this paper lattice-Boltzmann equation method is used to simulate non-Darcy flow in porous media. 2-D in-line and staggered arrangements of uniform cylinders have been considered. The results of a comprehensive computational evaluation are reported: the range of validity of Darcy-Forchheimer equation is investigated and correlations for macroscopic transport properties are presented (i. e., f...

A simple molecular model is studied to explain wall slip in a polymer melt. We consider a tube model for tethered chains in which the most important relaxation mechanisms: convective constraint release and chain stretching (retraction), are incorporated. Furthermore, we take the interactions between tethered chains and bulk flow self-consistently into account. Numerical simulations show that ou...