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An experimental test bed based on single particle tracking techniques is employed in order to investigate the velocity domain, slip velocity, and settling distribution of micro-particles in low-Reynolds number poiseuille flow in converging–diverging microchannel. Three-dimensional velocity domain of particles are studied in the presence of walls and compared with the particle-free fluid. The results show that the velocity of particles moving near the side walls of microchannel decreases about 30 % compared to those moving at the centerline. Furthermore, the effects of converging–diverging geometry on sedimentation of micro-particles are considered. The results show an average decrease of... 

An experimental test bed based on single particle tracking techniques is employed in order to investigate the velocity domain, slip velocity, and settling distribution of micro-particles in low-Reynolds number poiseuille flow in converging–diverging microchannel. Three-dimensional velocity domain of particles are studied in the presence of walls and compared with the particle-free fluid. The results show that the velocity of particles moving near the side walls of microchannel decreases about 30 % compared to those moving at the centerline. Furthermore, the effects of converging–diverging geometry on sedimentation of micro-particles are considered. The results show an average decrease of... 

Today, the flow of gas-solid, solid-liquid and liquid-liquid mixtures is broadly used in many industries such as slurry transportation, propulsion, dredging and power generation equipment. In this paper, single solid particle motion through free and forced vortices is analytically studied. The equations are solved for cases in which the drag, pressure gradient, added mass, buoyancy and weight forces are considered individually and simultaneously. Verification has been done for the value of ReP , which confirms the solution for the first t = 0.1 s. The results show that the most important force governing particle motion is the pressure gradient force  

In this paper, the hydrodynamic drag and lift forces on microparticles in a dilute suspension in low Reynolds number Poiseuille flow in a microchannel is experimentally investigated using microscopic image analysis. An effective technique is applied to manipulate single-particle tracking in order to determine the velocity field and hydrodynamic forces on microparticles with diameter-to-channel height ratio of 0.1 (Formula presented.) in microchannels. The results show that there is a distance near the walls of the channel in which the hydrodynamic coupling between the particles and channel walls is considerable. Also, the magnitude of drag force that is imposed on the particles with... 

In this article, velocity field and settling distribution of microparticles in a dilute suspension in low-Reynolds-number Poiseuille flow in a microchannel is experimentally investigated using microscopic image analysis. An effective technique is applied to manipulate single-particle tracking in order to determine the controlling parameters on transportation and settling of microparticles in microchannels. The results show that the velocities of dispersed phase are affected by the hydrodynamic properties, and this velocity deviation can be significant when the hydrodynamic coupling between particles and channel walls is considerable. Increasing the Reynolds number would result in decrease in...