Effect of slip on entropy generation in a single rotating disk in MHD flow

In the present study, the effect of slip on entropy generation in magnetohydrodynamic (MHD) flow over a rotating disk is investigated by semi-numerical analytical solution technique. The nonlinear governing equations of flow and thermal fields are reduced to ordinary differential equations by the Von Karman approach, then solved via differential transform method (DTM), a recently-developed, powerful analytical method. Related entropy generation equations are derived and nondimensionalized using geometrical and physical flow field-dependent parameters. For a rotating surface the form of slip introduced into the governing equations is rarefaction. For comparison, slip and no-slip regimes in the range 0.1 > Kn > 0 and their interaction with magnetic effects are investigated by minimum entropy generation. While minimizing entropy generation, equipartitioning is encountered between fluid friction irreversibility and Joule dissipation.Entropy generation minimization EGM Slip flow MHD flow Rotating disk Genetic algorithms Equipartition of entropy production (EoEP) Second law of thermodynamics

Nonlinear Dynamic Analysis of a Curved Sandwich Beam with a Time-Dependent Viscoelastic Core Using the Generalized Differential Quadrature Method (GDQM)

This paper focuses on the geometrically nonlinear dynamic analyses of a three-layered curved sandwich beam with isotropic face layers and a time-dependent viscoelastic core. The boundary conditions and equations of motion governing the forced vibration are derived by using Hamilton’s principle. The first-order shear deformation theory is used to obtain kinematic relations. The spatial discretization of the equations is achieved using the generalized differential quadrature method (GDQM), and the Newmark-Beta algorithm is used to solve the time variation of the equations. The Newton–Raphson method is used to transform nonlinear equations into linear equations. The validation of the proposed model and the GDQM solution’s reliability are provided via comparison with the results that already exist in the literature and finite element method (FEM) analyses using ANSYS. Then, a series of parametric studies are carried out for a curved sandwich beam with aluminum face layers and a time-dependent viscoelastic core. The resonance and cancellation phenomena for the nonlinear moving-load problem of curved sandwich beams with a time-dependent viscoelastic core are performed using the GDQM for the first time, to the best of the authors’ knowledge