The swirling nanofluid flow driven by a revolving bottom disk of a cylindrical container under magnetic field effect and temperature gradient is examined in this study. The effects of the electrical conductivity of cylindrical walls’ on heat transfer enhancement are quantitatively investigated. The finite volume approach is used to solve the governing equations under the appropriate assumptions. This study considers four cases of combined electric conducting and insulating walls. The solid nanoparticle (copper) with volume fraction (ϕ = 0.1) is added to water. Calculations were done for fixed Reynolds number (Re=1000), Richardson number (0≤Ri ≤2), and various Hartmann numbers. The mean Nusselt number decreased as the Richardson number increased owing to stratification layers. These latter restrict heat exchanges between the cylinder’s hot and cold zones. The results show that within a particular range of Hartmann numbers, the Nusselt number increases, especially when the revolving lid is electrically conducting. The best heat transfer occurs when all of the walls are electrically conductive, which results in a 100% improvement at low Richardson values. Finally, the electrical conductivity of the revolving lid was a key factor in enhancing heat transfer.

The present article examines the problem related to the axisymmetric torsion of an elastic layer by a circular rigid disc at the symmetry plane. The layer is sandwiched between two similar elastic half-spaces with two penny-shaped cracks symmetrically located at the interfaces between the two bonded dissimilar media. The mixed boundary-value problem is transformed, by means of the Hankel integral transformation, to dual integral equations, that are reduced, to a Fredholm integral equation of the second kind. The numerical methods are used to convert the resulting system to a system of infinite algebraic equations. Some physical quantities such as the stress intensity factor and the moment are calculated and presented numerically according to some relevant parameters. The numerical results show that the discontinuities around the crack and the inclusion cause a large increase in the stresses that decay with distance from the disc-loaded. Furthermore, the dependence of the stress intensity factor on the disc size, the distance between the crack and the disc, and the shear parameter is also observerd.

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