The Experts below are selected from a list of 261 Experts worldwide ranked by ideXlab platform

Hazem Ali Attia - One of the best experts on this subject based on the ideXlab platform.

  • Unsteady flow of a dusty Bingham fluid through a porous medium in a circular pipe
    Journal of Applied Mechanics and Technical Physics, 2016
    Co-Authors: Hazem Ali Attia, Mostafa A M Abdeen, W. Abbas, A. L. Aboul-hassan, M. A. Ibrahim
    Abstract:

    A time-varying flow through a porous medium of a dusty viscous incompressible Bingham fluid in a circular pipe is studied. A Constant Pressure Gradient is applied in the axial direction, whereas the particle phase is assumed to behave as a viscous fluid. The effect of the medium porosity, the non-Newtonian fluid characteristics, and the particle phase viscosity on the transient behavior of the velocity, volumetric flow rates, and skin friction coefficients of both the fluid and particle phases is investigated. A numerical solution is obtained for the governing nonlinear momentum equations by using the method of finite differences.

  • Unsteady flow in a porous medium between parallel plates in the presence of uniform suction and injection with heat transfer
    International Journal of Civil Engineering, 2014
    Co-Authors: Hazem Ali Attia, W. A. El-meged, W. Abbas, Mostafa A M Abdeen
    Abstract:

    The unsteady flow in porous medium of a viscous incompressible fluid bounded by two parallel porous plates is studied with heat transfer. A uniform and Constant Pressure Gradient is applied in the axial direction whereas a uniform suction and injection are applied in the direction normal to the plates. The two plates are kept at Constant and different temperatures and the viscous dissipation is not ignored in the energy equation. The effect of the porosity of the medium and the uniform suction and injection velocity on both the velocity and temperature distributions are investigated.

  • unsteady couette flow of a thermally conducting viscoelastic fluid under Constant Pressure Gradient in a porous medium
    Chinese Journal of Physics, 2014
    Co-Authors: Hazem Ali Attia, Ahmed Lotfyaboulhassan, Mostafa A M Abdeen, Alaa Eldin Abdin, Abd W Elmeged
    Abstract:

    Unsteady Couette flow through a porous medium of an incompressible non-Newtonian viscoelastic fluid between two parallel horizontal porous plates is studied. A Constant Pressure Gradient in the axial direction and a uniform suction and injection normal to the surface of the plates are applied. The two plates are kept at different but Constant temperatures, heat transfer through the conducting fluid is considered, and viscous dissipation is not neglected. Numerical solutions for the governing momentum and energy equations are obtained using the finite difference method. The results show that the porosity of the medium and the departure from the Newtonian characteristics of the fluid to viscoelasticity result in a drop in the velocity of flow and a drop in temperature and change the transient duration. The suction and injection reduce both the velocity and temperature at the middle plane.

  • ON THE EFFECTIVENESS OF VARIATION OF PHYSICAL VARIABLES ON STEADY FLOW BETWEEN PARALLEL PLATES WITH HEAT TRANSFER IN A POROUS MEDIUM
    Journal of Theoretical and Applied Mechanics, 2013
    Co-Authors: Hazem Ali Attia, Mostafa A M Abdeen
    Abstract:

    Theeffectofvariationofphysicalvariablesonasteadyflowthroughaporousmediumwith heattransferbetweenparallelplatesisexamined.Theviscosityandthethermalconductivity are assumed to be temperature dependent. A Constant Pressure Gradient is applied in the axialdirectionandthetwoplatesarekeptattwoConstantbutdifferenttemperatures,while the viscous dissipation is considered in the energy equation. A numerical solution for the governingnon-linearcoupledequationsofmotionandtheenergyequationisdetermined.The effectofporosityofthemedium,thevariableviscosity,andthevariablethermalconductivity onboththevelocityandtemperaturedistributionsis reported.

  • TRANSIENT CIRCULAR PIPE MHD FLOW OF A DUSTY FLUID CONSIDERING THE HALL EFFECT
    2011
    Co-Authors: Hazem Ali Attia
    Abstract:

    In this paper, the transient flow of a dusty viscous incompressible electrically conducting fluid through a circular pipe is studied taking the Hall effect into consideration. A Constant Pressure Gradient in the axial direction and an uniform magnetic field directed perpendicular to the flow direction are applied. The particle-phase is assu- med to behave as a viscous fluid. A numerical solution is obtained for the governing non- linear equations using finite differences.

Mostafa A M Abdeen - One of the best experts on this subject based on the ideXlab platform.

  • Unsteady flow of a dusty Bingham fluid through a porous medium in a circular pipe
    Journal of Applied Mechanics and Technical Physics, 2016
    Co-Authors: Hazem Ali Attia, Mostafa A M Abdeen, W. Abbas, A. L. Aboul-hassan, M. A. Ibrahim
    Abstract:

    A time-varying flow through a porous medium of a dusty viscous incompressible Bingham fluid in a circular pipe is studied. A Constant Pressure Gradient is applied in the axial direction, whereas the particle phase is assumed to behave as a viscous fluid. The effect of the medium porosity, the non-Newtonian fluid characteristics, and the particle phase viscosity on the transient behavior of the velocity, volumetric flow rates, and skin friction coefficients of both the fluid and particle phases is investigated. A numerical solution is obtained for the governing nonlinear momentum equations by using the method of finite differences.

  • Unsteady flow in a porous medium between parallel plates in the presence of uniform suction and injection with heat transfer
    International Journal of Civil Engineering, 2014
    Co-Authors: Hazem Ali Attia, W. A. El-meged, W. Abbas, Mostafa A M Abdeen
    Abstract:

    The unsteady flow in porous medium of a viscous incompressible fluid bounded by two parallel porous plates is studied with heat transfer. A uniform and Constant Pressure Gradient is applied in the axial direction whereas a uniform suction and injection are applied in the direction normal to the plates. The two plates are kept at Constant and different temperatures and the viscous dissipation is not ignored in the energy equation. The effect of the porosity of the medium and the uniform suction and injection velocity on both the velocity and temperature distributions are investigated.

  • unsteady couette flow of a thermally conducting viscoelastic fluid under Constant Pressure Gradient in a porous medium
    Chinese Journal of Physics, 2014
    Co-Authors: Hazem Ali Attia, Ahmed Lotfyaboulhassan, Mostafa A M Abdeen, Alaa Eldin Abdin, Abd W Elmeged
    Abstract:

    Unsteady Couette flow through a porous medium of an incompressible non-Newtonian viscoelastic fluid between two parallel horizontal porous plates is studied. A Constant Pressure Gradient in the axial direction and a uniform suction and injection normal to the surface of the plates are applied. The two plates are kept at different but Constant temperatures, heat transfer through the conducting fluid is considered, and viscous dissipation is not neglected. Numerical solutions for the governing momentum and energy equations are obtained using the finite difference method. The results show that the porosity of the medium and the departure from the Newtonian characteristics of the fluid to viscoelasticity result in a drop in the velocity of flow and a drop in temperature and change the transient duration. The suction and injection reduce both the velocity and temperature at the middle plane.

  • ON THE EFFECTIVENESS OF VARIATION OF PHYSICAL VARIABLES ON STEADY FLOW BETWEEN PARALLEL PLATES WITH HEAT TRANSFER IN A POROUS MEDIUM
    Journal of Theoretical and Applied Mechanics, 2013
    Co-Authors: Hazem Ali Attia, Mostafa A M Abdeen
    Abstract:

    Theeffectofvariationofphysicalvariablesonasteadyflowthroughaporousmediumwith heattransferbetweenparallelplatesisexamined.Theviscosityandthethermalconductivity are assumed to be temperature dependent. A Constant Pressure Gradient is applied in the axialdirectionandthetwoplatesarekeptattwoConstantbutdifferenttemperatures,while the viscous dissipation is considered in the energy equation. A numerical solution for the governingnon-linearcoupledequationsofmotionandtheenergyequationisdetermined.The effectofporosityofthemedium,thevariableviscosity,andthevariablethermalconductivity onboththevelocityandtemperaturedistributionsis reported.

Emanuel Negrão Macêdo - One of the best experts on this subject based on the ideXlab platform.

  • Integral transform analysis of MHD flow and heat transfer in parallel-plates channels
    International Communications in Heat and Mass Transfer, 2007
    Co-Authors: Jotao A. Lima, Joao N. N. Quaresma, Emanuel Negrão Macêdo
    Abstract:

    Abstract A hybrid solution through the so-called Generalized Integral Transform Technique (GITT) is obtained for the MHD flow and heat transfer of a Newtonian fluid in parallel-plates channels. A simple mathematical formulation for the problem is adopted, which evidences both the transient regime flow sustainable only by a Constant Pressure Gradient; and the steady state situation that considers both a Constant Pressure Gradient and a movement of the upper plate, as well as the action of an inflow and outflow perpendicular to the porous plates. Results for the velocity and temperature fields are computed within the governing parameters, namely, Pressure Gradient, suction velocity, upper plate velocity and Hartmann numbers, for typical situations. A convergence analysis is also performed showing the consistency of the results. In addition, the present results are confronted with those previously reported ones in the literature showing excellent agreements.

Jotao A. Lima - One of the best experts on this subject based on the ideXlab platform.

  • Integral transform analysis of MHD flow and heat transfer in parallel-plates channels
    International Communications in Heat and Mass Transfer, 2007
    Co-Authors: Jotao A. Lima, Joao N. N. Quaresma, Emanuel Negrão Macêdo
    Abstract:

    Abstract A hybrid solution through the so-called Generalized Integral Transform Technique (GITT) is obtained for the MHD flow and heat transfer of a Newtonian fluid in parallel-plates channels. A simple mathematical formulation for the problem is adopted, which evidences both the transient regime flow sustainable only by a Constant Pressure Gradient; and the steady state situation that considers both a Constant Pressure Gradient and a movement of the upper plate, as well as the action of an inflow and outflow perpendicular to the porous plates. Results for the velocity and temperature fields are computed within the governing parameters, namely, Pressure Gradient, suction velocity, upper plate velocity and Hartmann numbers, for typical situations. A convergence analysis is also performed showing the consistency of the results. In addition, the present results are confronted with those previously reported ones in the literature showing excellent agreements.

Michael J. Mccarthy - One of the best experts on this subject based on the ideXlab platform.

  • Turbulent pipe flow studied by time-averaged NMR imaging: measurements of velocity profile and turbulent intensity.
    Magnetic resonance imaging, 1994
    Co-Authors: Joseph D. Seymour, Robert L. Powell, Kathryn L. Mccarthy, Lars Ödberg, Michael J. Mccarthy
    Abstract:

    A time-averaged method to obtain quantitative measurements in turbulent flow by phase flow encoding NMR imaging is introduced. With this method time-averaged velocity profiles and turbulence intensities can be determined. Time-averaged velocity profiles for pipe flow of water driven by a Constant Pressure Gradient at Reynolds numbers from 1200 to 9400 were visualized. A precise correlation between the pixel intensity of the time-averaged NMR flow image and the local turbulence intensity of the flow is derived. The measured turbulence intensities are in agreement with published data obtained using other experimental methods.