The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Mohsen Torabi - One of the best experts on this subject based on the ideXlab platform.
-
novel solution for acceleration motion of a vertically falling non Spherical Particle by vim pade approximant
Powder Technology, 2012Co-Authors: Hessameddin Yaghoobi, Mohsen TorabiAbstract:Abstract In this paper, the acceleration motion of a vertically falling non-Spherical Particle in incompressible Newtonian media was investigated. The velocity and acceleration were carried out using analytical solution techniques i.e., the variational iteration method (VIM) and a Pade approximant. The results were also compared with VIM and the established fourth order Runge–Kutta method in order to verify the accuracy of the proposed method. It was shown that this method can lead into more accurate results compared with VIM.
-
novel solution for acceleration motion of a vertically falling Spherical Particle by hpm pade approximant
Advanced Powder Technology, 2011Co-Authors: Mohsen Torabi, Hessameddin YaghoobiAbstract:Abstract In this paper the acceleration motion of a vertically falling Spherical Particle in incompressible Newtonian media is investigated. The velocity is evaluated by using homotopy perturbation method (HPM) and Pade approximant which is an analytical solution technique. The current results are then compared with those derived from HPM and the established fourth order Runge–Kutta method in order to verify the accuracy of the proposed method. It is found that this method can achieve more suitable results in comparison to HPM.
Hessameddin Yaghoobi - One of the best experts on this subject based on the ideXlab platform.
-
novel solution for acceleration motion of a vertically falling non Spherical Particle by vim pade approximant
Powder Technology, 2012Co-Authors: Hessameddin Yaghoobi, Mohsen TorabiAbstract:Abstract In this paper, the acceleration motion of a vertically falling non-Spherical Particle in incompressible Newtonian media was investigated. The velocity and acceleration were carried out using analytical solution techniques i.e., the variational iteration method (VIM) and a Pade approximant. The results were also compared with VIM and the established fourth order Runge–Kutta method in order to verify the accuracy of the proposed method. It was shown that this method can lead into more accurate results compared with VIM.
-
novel solution for acceleration motion of a vertically falling Spherical Particle by hpm pade approximant
Advanced Powder Technology, 2011Co-Authors: Mohsen Torabi, Hessameddin YaghoobiAbstract:Abstract In this paper the acceleration motion of a vertically falling Spherical Particle in incompressible Newtonian media is investigated. The velocity is evaluated by using homotopy perturbation method (HPM) and Pade approximant which is an analytical solution technique. The current results are then compared with those derived from HPM and the established fourth order Runge–Kutta method in order to verify the accuracy of the proposed method. It is found that this method can achieve more suitable results in comparison to HPM.
Yoshimasa Kawata - One of the best experts on this subject based on the ideXlab platform.
-
Photon force analysis for a Spherical Particle near a substrate illuminated by a tightly focused laser beam
Journal of Applied Physics, 2003Co-Authors: Wataru Inami, Yoshimasa KawataAbstract:We present an analysis of the radiation force acting on a Spherical Particle near a substrate that is illuminated by a tightly focused laser beam. The Particle may be trapped at multiple positions due to multiscattering between the Particle and the substrate. The Particle is attracted to the substrate when the two are very close to each other, because the multiscattering produces a high-intensity region on the substrate surface. In many instances we found that a precise control of the focal position was necessary in order to scan the Particle on the substrate surface. On the basis of the results of our analysis, we also compare the potentials of radiation forces on the Particle with and without a substrate.
M. S. Faltas - One of the best experts on this subject based on the ideXlab platform.
-
Force on a Spherical Particle oscillating in a viscous fluid perpendicular to an impermeable planar wall
Journal of the Brazilian Society of Mechanical Sciences and Engineering, 2019Co-Authors: H. H. Sherief, M. S. Faltas, Shreen El-sapaAbstract:The slow motion of a hard Spherical Particle embedded in a semi-infinite viscous fluid bounded by an impermeable plane wall is considered. The Particle oscillates with small amplitude along a diameter perpendicular to the wall. At both surfaces of the Particle and plane wall, the no-slip kinematic condition is used. An analytical procedure with a numerical solution based on collocation technique is considered. The solution is found to be accurate for the low and high frequency of oscillations. The drag force coefficients acting on the Particle are plotted and tabulated against the frequency and the separation distance. The drag coefficients are found in good agreement with the corresponding problem of a steady case and with the oscillation of a Particle embedded in an infinite viscous fluid.
-
Theory of thermophoresis of a Spherical Particle embedded in a micropolar fluid
Journal of Molecular Liquids, 2019Co-Authors: E. I. Saad, M. S. FaltasAbstract:Abstract Analytical investigations are considered for the related problems of thermophoresis, photophoresis and thermophoresis with chemical reactions of a Spherical aerosol Particle embedded in a gaseous micropolar medium. The Knudsen number is assumed to be in the slip-flow regime. Viscous and gyrational dissipations are ignored in the energy equation. At the surface of the Particle, a thermal stress slip and the creep slip are considered in the analysis of motion. Expressions for thermophoretic and photophoretic velocities and forces are obtained as functions of the micropolarity parameter characterizing the micropolar medium and the thermal properties of the medium and Particle. Results of the effect of the chemical reaction within the Particle on its thermophoresis velocity are presented for various distributions of the composition-dependent factor or heat generation parameter of the chemical reaction as well as the relative thermal and surface properties of the aerosol Spherical Particle. The corresponding limiting cases of the classical viscous fluids are obtained.
-
Time-dependent electrophoresis of a dielectric Spherical Particle embedded in Brinkman medium
Zeitschrift für angewandte Mathematik und Physik, 2018Co-Authors: E. I. Saad, M. S. FaltasAbstract:An expression for electrophoretic apparent velocity slip in the time-dependent flow of an electrolyte solution saturated in a charged porous medium within an electric double layer adjacent to a dielectric plate under the influence of a tangential uniform electric field is derived. The velocity slip is used as a boundary condition to solve the electrophoretic motion of an impermeable dielectric Spherical Particle embedded in an electrolyte solution saturated in porous medium under the unsteady Darcy–Brinkman model. Throughout the system, a uniform electric field is applied and maintains with constant strength. Two cases are considered, when the electric double layer enclosing the Particle is thin, but finite and when of a Particle with a thick double layer. Expressions for the electrophoretic mobility of the Particle as functions of the relevant parameters are found. Our results indicate that the time scale for the growth of mobility is significant and small for high permeability. Generally, the effect of the relaxation time for starting electrophoresis is negligible, irrespective of the thickness of the double layer and permeability of the medium. The effects of the elapsed time, permeability, mass density and Debye length parameters on the fluid velocity, the electrophoretic mobility and the acceleration are shown graphically.
-
slow motion of a slip Spherical Particle along the axis of a circular cylindrical pore in a micropolar fluid
Journal of Molecular Liquids, 2014Co-Authors: H. H. Sherief, M. S. Faltas, E A Ashmawy, M G NashwanAbstract:Abstract The quasi-steady translational motion of a slip Spherical Particle in a micropolar fluid along the centerline of a circular cylindrical pore is investigated theoretically in the limit of small Reynolds numbers. The general solution of the problem at hand is constructed using the superposition of fundamental solutions in both cylindrical and Spherical coordinate systems. The imposed boundary conditions on the cylindrical and Spherical boundaries are applied and a collocation technique is utilized. Numerical results for the normalized drag force exerted on the Particle are obtained with good convergence for various values of the ratio of Particle-to-pore radii, slip coefficient and micropolarity parameter.
Wataru Inami - One of the best experts on this subject based on the ideXlab platform.
-
Photon force analysis for a Spherical Particle near a substrate illuminated by a tightly focused laser beam
Journal of Applied Physics, 2003Co-Authors: Wataru Inami, Yoshimasa KawataAbstract:We present an analysis of the radiation force acting on a Spherical Particle near a substrate that is illuminated by a tightly focused laser beam. The Particle may be trapped at multiple positions due to multiscattering between the Particle and the substrate. The Particle is attracted to the substrate when the two are very close to each other, because the multiscattering produces a high-intensity region on the substrate surface. In many instances we found that a precise control of the focal position was necessary in order to scan the Particle on the substrate surface. On the basis of the results of our analysis, we also compare the potentials of radiation forces on the Particle with and without a substrate.
