The Experts below are selected from a list of 249 Experts worldwide ranked by ideXlab platform

Yan-hua Yang - One of the best experts on this subject based on the ideXlab platform.

  • Theoretical models of Turbulent Flow in rolling motion
    Progress in Nuclear Energy, 2010
    Co-Authors: B.h. Yan, Yan-hua Yang
    Abstract:

    Abstract The Flowing and heat transfer characteristics of Turbulent Flow in tubes and rectangular channels in rolling motion are investigated theoretically. The Flowing and heat transfer models of Turbulent Flow in rolling motion are established. The correlations of frictional resistance coefficient and Nusselt number are derived. The results are also validated with experiments. The effects of several parameters on frictional resistance coefficient and Nusselt number are investigated. The oscillating amplitude of Nusselt number is in direct ratio with Prandtl number and rolling frequency approximately. The more the Flowing velocity is, the less the effect of rolling motion on the Flow is. The variation of initial phase difference between Nusselt number and rolling motion with rolling frequency is very limited.

  • CFD Analysis of Turbulent Flow in Typical Rod Bundles in Rolling Motion
    Applied Mechanics and Materials, 2010
    Co-Authors: Bing Yan, Yan-hua Yang
    Abstract:

    The influence mechanism of rolling motion on the Flowing and heat transfer characteristics of Turbulent Flow in typical four rod bundles is investigated with FLUENT code. The Flowing and heat transfer characteristics of Turbulent Flow in rod bundles can be affected by rolling motion. But the Flowing similarity of Turbulent Flow in adiabatic and non-adiabatic can not be affected. If the rolling amplitude is big or if the rolling period is small, the radial additional force can make the parameter profiles and the Turbulent Flowing and heat transfer change greatly. And the frictional resistance coefficient and heat transfer coefficient can not be solved by the correlations in steady state. In rolling motion, as the pitch to diameter ratio decrease, especially if it is less than 1.1, the Flowing and heat transfer of Turbulent Flow in rolling motion change significantly.

Yu Lei - One of the best experts on this subject based on the ideXlab platform.

  • Flowing and Heat Transfer Characteristics of Turbulent Flow in Typical Rod Bundles at Rolling Motion
    Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2011
    Co-Authors: Yu Lei
    Abstract:

    The influence mechanism of rolling motion on the Flowing and heat transfer characteristics of Turbulent Flow in typical four rod bundles was investigated with Fluent code.The Flowing and heat transfer characteristics of Turbulent Flow in rod bundles can be affected by rolling motion.But the Flowing similarity of Turbulent Flow in adiabatic and non-adiabatic can not be affected.If the rolling period is small,the radial additional force can make the parameter profiles,the Turbulent Flowing and heat transfer change greatly.At rolling motion,as the pitch to diameter ratio decreases,especially if it is less than 1.1,the Flowing and heat transfer of Turbulent Flow at rolling motion change significantly.The variation of pitch to diameter ratio can change the profiles of secondary Flow and Turbulent kinetic energy in cross-section greatly.

  • LES Research on Flowing Characteristics of Turbulent Flow in Rectangular Tubes in Rolling Motion
    Nuclear Power Engineering, 2011
    Co-Authors: Yu Lei
    Abstract:

    The Turbulent Flow in rectangular tubes in rolling motion is investigated theoretically with FLUENT code and large eddy simulation.The effects of rolling motion and tube size on the Flowing characteristics of Turbulent Flow are analyzed.The results show that if the rectangular tube is narrow,the effect of rolling motion on the Turbulent Flow can be depressed by the tube wall.If the rolling amplitude is small,the effect of rolling motion on the Turbulent Flow is very limited.With the decrease of length-width ratio of the tube,the Turbulent frictional resistance coefficient decreases.The frictional resistance coefficient is in a wave or slope shape.If the rolling amplitude is big,the counter Flow occurs first at the π/2 phase.With the decrease of rolling period,the frictional resistance coefficient on the wall decreases first,and increases later.

  • Theoretical Research on Effect of Rolling Motion on Turbulent Flow
    Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2010
    Co-Authors: Yu Lei
    Abstract:

    The Turbulent Flow in rectangular tube at rolling motion was investigated theoretically with Fluent code.The effects of several Turbulent models and parameters on the Flow were analyzed.At rolling motion,the velocity profile in tube center is more averaged.But the velocity gradient and frictional resistance coefficient on the wall increase.The effect of rolling motion on the Turbulent Flow can be depressed by the tube wall.At pitching motion,the velocity contour in small length-width ratio tube is in a dumbbell shape.As to the Turbulent Flow in the paper,the frictional resistance coefficient at rolling motion is in inverse ratio with the power of 0.47 of Reynolds number.

W. F. Hughes - One of the best experts on this subject based on the ideXlab platform.

  • Squeeze Film Dynamics of Two-Phase Seals: Part II—Turbulent Flow
    Journal of Tribology, 1994
    Co-Authors: J. A. Yasuna, W. F. Hughes
    Abstract:

    A previously developed dynamic model for two-phase face seals is extended to include Turbulent Flow. Thermal transients over the entire range of laminar and Turbulent Flow are considered for both parallel and tapered geometries. Inlet losses and choking are accounted for in the Turbulent regime. Axial responses to perturbations from equilibrium are examined, and general criteria are discussed for predicting stable, unstable and bistable seal operation

Sauro Succi - One of the best experts on this subject based on the ideXlab platform.

  • Polymer dynamics in wall Turbulent Flow
    Europhysics Letters (EPL), 2002
    Co-Authors: Patrick Ilg, E. De Angelis, Iliya V. Karlin, Carlo Massimo Casciola, Sauro Succi
    Abstract:

    The dynamics of dilute polymer solutions is investigated in wall Turbulent Flow. A realistic Turbulent Flow field is obtained by a fully coupled direct numerical simulation of a drag-reducing polymer solution. This Flow field is used to compare the microscopic and macroscopic description of the polymer dynamics. It is observed that polymers become highly oriented parallel to the mean Flow direction. The stretching of the polymers is characterized by a broad distribution of polymer extensions. Finally, the Gaussian manifold corresponding to the macroscopic description of the polymer dynamics is found to be unstable in the present Flow.

Fabrice Gritti - One of the best experts on this subject based on the ideXlab platform.