The Experts below are selected from a list of 86478 Experts worldwide ranked by ideXlab platform

Xiao Zhen - One of the best experts on this subject based on the ideXlab platform.

Dimos Poulikakos - One of the best experts on this subject based on the ideXlab platform.

  • Parallel-flow and counter-flow conjugate convection from a vertical insulated pipe
    Journal of Thermophysics and Heat Transfer, 1990
    Co-Authors: J. Libera, Dimos Poulikakos
    Abstract:

    The coupling of forced convection inside a vertical pipe and natural convection outside the pipe is investigated for the case where the pipe is surrounded by permeable insulation. This analysis is pertinent to the design of insulation jackets for pipes, where the insulation can be modeled as an isotropic porous Medium. Attention is given to the cases of both parallel flow and counterflow. The heat transfer through the pipe wall is a direct result of the interaction between the forced convection outside the pipe and the natural convection outside the pipe. 9 refs.

Ioan Pop - One of the best experts on this subject based on the ideXlab platform.

  • Forced convection past a heated cylinder in a porous Medium using a thermal nonequilibrium model: Boundary layer analysis
    European Journal of Mechanics - B Fluids, 2003
    Co-Authors: D. Andrew S. Rees, Andrew P. Bassom, Ioan Pop
    Abstract:

    Abstract We study the forced convective heat transfer from a uniform temperature cylinder placed perpendicular to an otherwise uniform fluid stream in a porous Medium. Attention is focussed on how the absence of local thermal equilibrium between the solid and fluid phases affects the rate of heat transfer from the cylinder when the Peclet number is very large. It is found in all cases that the surface rate of heat transfer for the fluid is always greater than that of the solid matrix. Detailed numerical results are given for a wide range of parameter values, and these are supplemented by asymptotic analyses for both small and large values of the inter-phase heat transfer coefficient, H. When this coefficient is small the thermal field corresponding to the solid phase occupies a much greater region than does the thermal field of the fluid phase.

Alberto Favaro - One of the best experts on this subject based on the ideXlab platform.

  • Plane-Wave Propagation in Extreme Magnetoelectric Media
    IEEE Transactions on Antennas and Propagation, 2016
    Co-Authors: Ismo V. Lindell, Ari Sihvola, Alberto Favaro
    Abstract:

    The extreme magnetoelectric (EME) Medium is defined in terms of two Medium dyadics, $ {\overline {\overline {\mathsf \alpha }}}$ , producing electric polarization by the magnetic field and $ {\overline {\overline {\mathsf \beta }}}$ , producing magnetic polarization by the electric field. Plane-wave propagation of time-harmonic fields of fixed finite frequency in the EME Medium is studied. It is shown that (if $\omega \neq 0$ ) the dispersion equation has a cubic and homogeneous form, whence the wave vector k is either zero or has arbitrary magnitude. In many cases there is no dispersion equation (“NDE Medium”) to restrict the wave vector in an EME Medium. Attention is paid to the case where the two Medium dyadics have the same set of eigenvectors. In such a case the k vector is restricted to three eigenplanes defined by the Medium dyadics. The emergence of such a result is demonstrated by considering a more regular Medium, and taking the limit of zero permittivity and inverse permeability. The special case of uniaxial EME Medium is studied in detail. It is shown that an interface of a uniaxial EME Medium appears as a DB boundary when the axis of the Medium is normal to the interface. More in general, EME media display interesting wave effects that can potentially be realized through metasurface engineering.

Meheboob Alam - One of the best experts on this subject based on the ideXlab platform.

  • Shear-flow and material instabilities in particulate suspensions and granular media
    Particulate Science and Technology, 1999
    Co-Authors: Joe D. Goddard, Meheboob Alam
    Abstract:

    This article is a review of recent theoretical work on shear flow instabilities of particulate suspensions and dry granular Medium. Attention is devoted largely to steady homogeneous unbounded simple shearing flows, as a generalization of the classical Kelvin problem for Newtonian fluids, with a view towards identifying material or constitutive instabilities arising from the coupling of stress to particulate concentration and temperature fields. After reviewing the most common constitutive models, a unified linear-stability treatment is given for suspensions and granular media, based on an assumed short-memory' response of stress and various fluxes to perturbations on materially steady and uniform base states. A two-dimensional stability analysis of inertialess suspension flow indicates the possibility of particle-depleted shear bands. A comprehensive three-dimensional analysis of rapid granular flow reveals transverse 'layering' and spanwise 'corrugations' as possible modes of instability. The latter appear to result from a kind of material instability, although not the simple short-wavelength instability found for suspensions. Based on the current theoretical treatments, several new studies are recommended, including the effects of granular dilatancy and yield stress, three-dimensional disturbances in suspensions and the effects of gravity in granular flow.