Study of thermal boundary conditions for a plain journal bearing

Three-dimensional energy and heat conduction equations for fluid and bush temperatures and a one-dimensional equation for journal temperature have been solved. Two alternative boundary conditions at the inlet have been examined. Heat transfer from bush to oil in supply groove is considered. A more appropriate boundary condition is identified.     

Analysis of annular Reissner/Mindlin plates using differential quadrature method

The axisymmetric flexure responses of moderately thick annular plates under static loading are investigated. The shear deformation is considered using the first-order Reissner/Mindlin plate theory and the solutions are obtained using the differential quadrature (DQ) method. In the solution process, the governing differential equations and boundary conditions for the problem are initially discretized by the DQ algorithm into a set of linear algebraic equations. The solutions of the problem are then determined by solving the set of algebraic equations. This study considers the plate subjected to various combinations of clamped, simply-supported, free and guided boundary conditions and different loading manners. The accuracy of the method is demonstrated through direct comparison of the present results with the corresponding exact solutions available in the literature.     

Transverse vibration of a circular plate with arbitrary thickness variation

Rayleigh-Ritz method has been employed to obtain approximations to frequencies and mode shapes of circular plates with variable thickness. The boundary is either clamped, simply supported or completely free. The main distinguishing feature of the present investigations is that the thickness approximation is done by measuring thickness at a suitable set of sample points and then using interpolation to get the approximating polynomial. Thus, unlike other methods already available in literature where either linear or quadratic variation of thickness has been examined, here one can have a polynomial of arbitrary degree depending upon the number and locations of the sample points. The results have been tabulated in a large number of cases and three-dimensional mode shapes have been plotted for some selected cases. Comparison has been made with available results. A short tables are also given to depict the rate of convergence with the order of approximation.     

Static electromechanical response of smart composite/sandwich plates using an efficient finite element with physical and electric nodes

An efficient quadrilateral element, recently developed by the authors, based on an improved zigzag theory is assessed for the static electromechanical response of hybrid plates with electroded piezoelectric sensors and actuators. The theory accounts for the transverse normal strain due to the electric field in the approximation of deflection. The electric potential is approximated as layerwise quadratic across the thickness. By introducing an electric node in the element for the electric potentials of the electroded piezoelectric surfaces, the equipotential condition of such surfaces is modelled very efficiently. The electric potential degrees of freedom (DOF) corresponding to the quadratic component of the electric potential distribution are associated with the four physical nodes to allow for the inplane electric field induced due to direct piezoelectric effect. The requirement of C¹ continuity of interpolation functions of the deflection is circumvented by employing the improved discrete Kirchhoff constraint technique. The finite element (FE) formulation is validated by comparing the results with other available results in the literature. Comparison of the present results for static response of a variety of piezoelectric bimorph, hybrid composite and sandwich plates, with 3D analytical and FE solutions and those of other available elements establishes that the present element is accurate, robust and computationally efficient.