MHD THREE-DIMENSIONAL STAGNATION-POINT FLOW OF A MICROPOLAR FLUID

The steady three-dimensional stagnation-point flow of an electrically conducting micropolar fluid in the absence and in the presence of a uniform external electromagnetic field (E0,H0) is analyzed and some physical situations are examined. In particular, we proved that if we impress an external magnetic field H0, and we neglect the induced magnetic field, then the steady MHD three-dimensional stagnation-point flow of such a fluid is possible if, and only if, H0 has the direction parallel to one of the axes. In all cases it is shown that the governing nonlinear partial differential equations admit similarity solutions. Moreover in the presence of an external magnetic field H0, it is found that the flow of a micropolar fluid has to satisfy an ordinary differential problem whose solution depend on H0 through the Hartmann number M. Finally, the skin-friction components along the axes are computed

MHD oblique stagnation-point flow of a Newtonian fluid

The steady two-dimensional oblique stagnation-point flow of an electrically conducting Newtonian fluid in the presence of a uniform external electromagnetic field (E0, H0) is analyzed, and some physical situations are examined. In particular, if E0 vanishes, H0 lies in the plane of the flow, with a direction not parallel to the boundary, and the induced magnetic field is neglected, it is proved that the oblique stagnation-point flow exists if, and only if, the external magnetic field is parallel to the dividing streamline. In all cases it is shown that the governing nonlinear partial differential equations admit similarity solutions, and the resulting ordinary differential problems are solved numerically. Finally, the behaviour of the flow near the boundary is analyzed; this depends on the Hartmann number if H0 is parallel to the dividing streamline

MHD OBLIQUE STAGNATION-POINT FLOW OF A MICROPOLAR FLUID

The steady two-dimensional oblique stagnation-point flow of an electrically conducting micropolar fluid in the presence of a uniform external electromagnetic field (E0,H0) is analyzed and some physical situations are examined. In particular, if E0 vanishes, H0 lies in the plane of the flow, with a direction not parallel to the boundary, and the induced magnetic field is neglected. It is proved that the oblique stagnationpoint flow exists if, and only if, the external magnetic field is parallel to the dividing streamline. In all cases it is shown that the governing nonlinear partial differential equations admit similarity solutions and the resulting ordinary differential problems are solved numerically. Finally, the behaviour of the flow near the boundary is analyzed; this depends on the three dimensionless material parameters, and also on the Hartmann number if H0 is parallel to the dividing streamline

MHD orthogonal stagnation-point flow of a micropolar fluid with the magnetic field parallel to the velocity at infinity

An exact solution is obtained for the steady MHD plane orthogonal stagnation-point flow of a homogeneous, incompressible, electrically conducting micropolar fluid over a rigid uncharged dielectric at rest. The space is permeated by a not uniform external magnetic field He and the total magnetic field H in the fluid is parallel to the velocity at infinity. The results obtained reveal many interesting behaviours of the flow and of the total magnetic field in the fluid and in the dielectric. In particular, the thickness of the layer where the viscosity appears depends on the strength of the magnetic field. The effects of the magnetic field on the velocity and on the microrotation profiles are presented graphically and discussed

Discontinuity waves of order r > or equal to 1 in an inhomogeneous anisotropic linear elastic solid

none1---noneM. C. PATRIAPatria, Maria Cristin

On flow and stability of a Newtonian fluid past a rotating plane

none1---noneM. C. PATRIAPatria, Maria Cristin

The behaviour of induced discontinuities behind a first order discontinuity wave for a quasilinear hyperbolic system

none2---noneA. Borrelli; M.C. PatriaBorrelli, Alessandra; Patria, Maria Cristin

Induced discontinuities in thermoviscoelastic solids of integral type

In this paper we study the induced discontinuities associated with a discontinuity wave of order N >= 1 propagating through a homogeneous anisotropic linear thermoviscoelastic solid whose heat flux vector depends upon the past history of the temperature gradient. After recalling the results of 1, 2, we state the evolution law of the induced discontinuity vector along the rays associated with the wave front. The results obtained depend on N through the mean curvature of the wave front

Energy bounds for a mixture of two linear elastic solids occupying a semi-infinite cylinder

The aim of this paper is to estblish some forms of the Saint-Venant principle for a mixture of two linear elastic solids occupying a semi-infinite prismatic cylinder. We examine the behaviour of the energy for both static and dynamical problems