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Xinxin Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Impact of Velocity Slip and Temperature Jump of Nanofluid in the Flow over a Stretching Sheet with Variable Thickness
    Zeitschrift für Naturforschung A, 2016
    Co-Authors: Chengjie Guo, Liancun Zheng, Chaoli Zhang, Xuehui Chen, Xinxin Zhang
    Abstract:

    AbstractIn this study, the generalised Velocity Slip and the generalised temperature jump of nanofluid in the flow over a stretching sheet with variable thickness are investigated. Because of the non-adherence of the fluid to a solid boundary, the Velocity Slip and the temperature jump between fluid and moving sheet may happen in industrial process, so taking Velocity Slip and temperature jump into account is indispensable. It is worth mentioning that the analysis of the Velocity v, which has not been seen in the previous references related to the variable thickness sheet, is presented. The thermophoresis and the Brownian motion, which are the two very important physical parameters, are fully studied. The governing equations are simplified into ordinary differential equations by the proper transformations. The homotopy analysis method (HAM) is applied to solve the reduced equations for general conditions. In addition, the effects of involved parameters such as Velocity Slip parameter, temperature jump parameter, Prandtl number, magnetic field parameter, permeable parameter, Lewis number, thermophoresis parameter, and Brownian motion parameter are investigated and analysed graphically.

  • Effects of second order Velocity Slip and nanoparticles migration on flow of Buongiorno nanofluid
    Applied Mathematics Letters, 2016
    Co-Authors: Jing Zhu, Liancun Zheng, Dan Yang, Xinxin Zhang
    Abstract:

    Abstract The present work analyzes the effects of second order Velocity Slip and nanoparticles migration on nanofluids between two rotating parallel plates. The classical Buongiorno model involves Brownian motion and thermophoretic diffusivities is modified by considering nanoparticle volume fraction distribution. Homotopy analysis method is employed to solve the equations, then the accuracy and efficiency of the HAM solutions are verified by h -curves and residual errors curves using package BVPh2.0. Physical interests in Nusselt number and skin friction as well as nanoparticles migration are illustrated by graphs.

  • Flow and Heat Transfer of Nanofluids Over a Rotating Porous Disk with Velocity Slip and Temperature Jump
    Zeitschrift für Naturforschung A, 2015
    Co-Authors: Chenguang Yin, Liancun Zheng, Chaoli Zhang, Xinxin Zhang
    Abstract:

    AbstractIn this article, we discuss the flow and heat transfer of nanofluids over a rotating porous disk with Velocity Slip and temperature jump. Three types of nanoparticles – Cu, Al2O3, and CuO – are considered with water as the base fluid. The nonlinear governing equations are reduced into ordinary differential equations by Von Karman transformations and solved using homotopy analysis method (HAM), which is verified in good agreement with numerical ones. The effects of involved parameters such as porous parameter, Velocity Slip, temperature jump, as well as the types of nanofluids on Velocity and temperature fields are presented graphically and analysed.

  • flow and radiation heat transfer of a nanofluid over a stretching sheet with Velocity Slip and temperature jump in porous medium
    Journal of The Franklin Institute-engineering and Applied Mathematics, 2013
    Co-Authors: Liancun Zheng, Chaoli Zhang, Xinxin Zhang, Junhong Zhang
    Abstract:

    Abstract In this paper, we present an investigation for the flow and radiation heat transfer of a nanofluid over a stretching sheet with Velocity Slip and temperature jump in porous medium. The Brownian motion and thermophoresis are taken into account according to Rosseland’s approximation. The governing coupled partial differential equations are non-dimensionalized and solved both numerically and analytically by local similarity method. The effects of involved parameters (Velocity Slip, temperature jump, thermal radiation, Prandtl number, Lewis number, Brownian motion, thermophoresis) on Velocity, temperature and concentration profiles are presented graphically and analyzed. Moreover, the numerical results are compared with the analytical solutions obtained by Homotopy analysis method with very good agreement to validate the present results.

  • DTM-BF method and dual solutions for unsteady MHD flow over permeable shrinking sheet with Velocity Slip
    Applied Mathematics and Mechanics, 2012
    Co-Authors: Liancun Zheng, Xinxin Zhang
    Abstract:

    An unsteady magnetohydrodynamic (MHD) boundary layer flow over a shrinking permeable sheet embedded in a moving viscous electrically conducting fluid is investigated both analytically and numerically. The Velocity Slip at the solid surface is taken into account in the boundary conditions. A novel analytical method named DTMBF is proposed and used to get the approximate analytical solutions to the nonlinear governing equation along with the boundary conditions at infinity. All analytical results are compared with those obtained by a numerical method. The comparison shows good agreement, which validates the accuracy of the DTM-BF method. Moreover, the existence ranges of the dual solutions and the unique solution for various parameters are obtained. The effects of the Velocity Slip parameter, the unsteadiness parameter, the magnetic parameter, the suction/injection parameter, and the Velocity ratio parameter on the skin friction, the unique Velocity, and the dual Velocity profiles are explored, respectively.

Livio Gibelli - One of the best experts on this subject based on the ideXlab platform.

  • Velocity Slip coefficients based on the hard-sphere Boltzmann equation
    Physics of Fluids, 2012
    Co-Authors: Livio Gibelli
    Abstract:

    We present a kinetic theory derivation of higher-order Slip boundary conditions. The situation studied is that of a pressure driven isothermal gas flowing through a plane microchannel. The distribution function is expanded in terms of half-range Hermite polynomials and the system of moment equations in the expansion coefficients is analytically solved. The Velocity Slip coefficients, as well as their Knudsen-layer corrections, are obtained by evaluating the solution in the near continuum limit. The proposed approach is accurate and easy to implement. The results are presented for the hard-sphere Boltzmann equation and Maxwell's diffuse-specular boundary conditions, but can be extended to arbitrary intermolecular interactions and more general scattering kernels.

Liancun Zheng - One of the best experts on this subject based on the ideXlab platform.

  • Impact of Velocity Slip and Temperature Jump of Nanofluid in the Flow over a Stretching Sheet with Variable Thickness
    Zeitschrift für Naturforschung A, 2016
    Co-Authors: Chengjie Guo, Liancun Zheng, Chaoli Zhang, Xuehui Chen, Xinxin Zhang
    Abstract:

    AbstractIn this study, the generalised Velocity Slip and the generalised temperature jump of nanofluid in the flow over a stretching sheet with variable thickness are investigated. Because of the non-adherence of the fluid to a solid boundary, the Velocity Slip and the temperature jump between fluid and moving sheet may happen in industrial process, so taking Velocity Slip and temperature jump into account is indispensable. It is worth mentioning that the analysis of the Velocity v, which has not been seen in the previous references related to the variable thickness sheet, is presented. The thermophoresis and the Brownian motion, which are the two very important physical parameters, are fully studied. The governing equations are simplified into ordinary differential equations by the proper transformations. The homotopy analysis method (HAM) is applied to solve the reduced equations for general conditions. In addition, the effects of involved parameters such as Velocity Slip parameter, temperature jump parameter, Prandtl number, magnetic field parameter, permeable parameter, Lewis number, thermophoresis parameter, and Brownian motion parameter are investigated and analysed graphically.

  • Effects of second order Velocity Slip and nanoparticles migration on flow of Buongiorno nanofluid
    Applied Mathematics Letters, 2016
    Co-Authors: Jing Zhu, Liancun Zheng, Dan Yang, Xinxin Zhang
    Abstract:

    Abstract The present work analyzes the effects of second order Velocity Slip and nanoparticles migration on nanofluids between two rotating parallel plates. The classical Buongiorno model involves Brownian motion and thermophoretic diffusivities is modified by considering nanoparticle volume fraction distribution. Homotopy analysis method is employed to solve the equations, then the accuracy and efficiency of the HAM solutions are verified by h -curves and residual errors curves using package BVPh2.0. Physical interests in Nusselt number and skin friction as well as nanoparticles migration are illustrated by graphs.

  • Flow and Heat Transfer of Nanofluids Over a Rotating Porous Disk with Velocity Slip and Temperature Jump
    Zeitschrift für Naturforschung A, 2015
    Co-Authors: Chenguang Yin, Liancun Zheng, Chaoli Zhang, Xinxin Zhang
    Abstract:

    AbstractIn this article, we discuss the flow and heat transfer of nanofluids over a rotating porous disk with Velocity Slip and temperature jump. Three types of nanoparticles – Cu, Al2O3, and CuO – are considered with water as the base fluid. The nonlinear governing equations are reduced into ordinary differential equations by Von Karman transformations and solved using homotopy analysis method (HAM), which is verified in good agreement with numerical ones. The effects of involved parameters such as porous parameter, Velocity Slip, temperature jump, as well as the types of nanofluids on Velocity and temperature fields are presented graphically and analysed.

  • flow and radiation heat transfer of a nanofluid over a stretching sheet with Velocity Slip and temperature jump in porous medium
    Journal of The Franklin Institute-engineering and Applied Mathematics, 2013
    Co-Authors: Liancun Zheng, Chaoli Zhang, Xinxin Zhang, Junhong Zhang
    Abstract:

    Abstract In this paper, we present an investigation for the flow and radiation heat transfer of a nanofluid over a stretching sheet with Velocity Slip and temperature jump in porous medium. The Brownian motion and thermophoresis are taken into account according to Rosseland’s approximation. The governing coupled partial differential equations are non-dimensionalized and solved both numerically and analytically by local similarity method. The effects of involved parameters (Velocity Slip, temperature jump, thermal radiation, Prandtl number, Lewis number, Brownian motion, thermophoresis) on Velocity, temperature and concentration profiles are presented graphically and analyzed. Moreover, the numerical results are compared with the analytical solutions obtained by Homotopy analysis method with very good agreement to validate the present results.

  • DTM-BF method and dual solutions for unsteady MHD flow over permeable shrinking sheet with Velocity Slip
    Applied Mathematics and Mechanics, 2012
    Co-Authors: Liancun Zheng, Xinxin Zhang
    Abstract:

    An unsteady magnetohydrodynamic (MHD) boundary layer flow over a shrinking permeable sheet embedded in a moving viscous electrically conducting fluid is investigated both analytically and numerically. The Velocity Slip at the solid surface is taken into account in the boundary conditions. A novel analytical method named DTMBF is proposed and used to get the approximate analytical solutions to the nonlinear governing equation along with the boundary conditions at infinity. All analytical results are compared with those obtained by a numerical method. The comparison shows good agreement, which validates the accuracy of the DTM-BF method. Moreover, the existence ranges of the dual solutions and the unique solution for various parameters are obtained. The effects of the Velocity Slip parameter, the unsteadiness parameter, the magnetic parameter, the suction/injection parameter, and the Velocity ratio parameter on the skin friction, the unique Velocity, and the dual Velocity profiles are explored, respectively.

Felix Sharipov - One of the best experts on this subject based on the ideXlab platform.

  • data on the Velocity Slip and temperature jump on a gas solid interface
    Journal of Physical and Chemical Reference Data, 2011
    Co-Authors: Felix Sharipov
    Abstract:

    The present review is dedicated to the Velocity Slip and temperature jump coefficients applied to modeling of gas flows. Such coefficients are used when a moderate gas rarefaction must be taken into account. In this case, calculations of gas flows can be performed on the basis of continuum mechanics equations applying the Velocity Slip and temperature jump boundary conditions. Thus, the Velocity Slip and temperature jump coefficients have the same importance in gas dynamics as the transport coefficients such as viscosity, thermal conductivity, and diffusion coefficients. A critical analysis of theoretical and experimental data on the Slip and jump coefficients available in the open literature is presented in an accessible form so that it can be easily understandable for nonspecialists in rarefied gas dynamics. The most reliable results are selected and tabulated. The results cover a single gas with the complete and noncomplete accommodation on a solid surface, gaseous mixtures, and polyatomic gases. Many ...

  • data on the Velocity Slip and temperature jump on a gas solid interface
    Journal of Physical and Chemical Reference Data, 2011
    Co-Authors: Felix Sharipov
    Abstract:

    The present review is dedicated to the Velocity Slip and temperature jump coefficients applied to modeling of gas flows. Such coefficients are used when a moderate gas rarefaction must be taken into account. In this case, calculations of gas flows can be performed on the basis of continuum mechanics equations applying the Velocity Slip and temperature jump boundary conditions. Thus, the Velocity Slip and temperature jump coefficients have the same importance in gas dynamics as the transport coefficients such as viscosity, thermal conductivity, and diffusion coefficients. A critical analysis of theoretical and experimental data on the Slip and jump coefficients available in the open literature is presented in an accessible form so that it can be easily understandable for nonspecialists in rarefied gas dynamics. The most reliable results are selected and tabulated. The results cover a single gas with the complete and noncomplete accommodation on a solid surface, gaseous mixtures, and polyatomic gases. Many examples of applications of the Slip and jump boundary conditions are given. The review will be useful as a reference for mathematicians, physicists, and engineers dealing with flows of moderately rarefied gases.

  • Data on the Velocity Slip and Temperature Jump Coefficients
    2004
    Co-Authors: Felix Sharipov
    Abstract:

    Modeling niicrofluidics it is necessary to calculate gas flows through micropumps, microvalves and other elements. A heat transfer through a gas in microscales must be also known for modeling of microsystems. Since the size of niicrosystems is close to the molecular mean free path, the gas rarefaction must be taken into account. If the Knudsen number is moderately small then gas flows and heat transfer can be calculated applying the continuum mechanics equations with the Velocity Slip and temperature jump boundary conditions. In the present work, a critical review of the theoretical results on the Slip and jump coefficients and their recommended data are given.

Silvia Lorenzani - One of the best experts on this subject based on the ideXlab platform.