Laser ablation of Ta plates using nanosecond optical vortex pulses was carried out, for the first time. It was suggested that owing to orbital angular momentum of optical vortex, clearer and smoother processed surfaces were obtained with less ablation threshold fluence, in comparison with the ablation by a nonvortex annular beam modified from a spatially Gaussian beam.

Deduce the velocity distribution of steady flow of an incompressible fluid of density ρ and viscosity η between two parallel, coaxial annular plates of inner radii r1, outer radii r2 and separation h when pressure difference ∆P is applied between the inner and outer radii. As an exact solution of the Navier-Stokes equation appears to be difficult, it suffices to give an approximate solution ass...

This paper presents the bending analysis of annular plates by the indirect Trefftz boundary approach. The formulation for thin and thick plates is based on the Kirchhoff plate theory and the Reissner plate theory. The governing equations are therefore a fourth-order boundary value problem and a sixth-order boundary value problem, respectively. The Trefftz method employs the complete set of solu...

the buckling analysis of annular composite plates reinforced by carbon nanotubes subjected to compressive and torsional loads are studied in this paper. the mori-tanaka method is employed to calculate the effective elastic modulus of composites having aligned oriented straight cnts. the effects of cnts volume fractions, orientation angles, boundary conditions and geometric ratio of plate are di...

Herein paper compares the analytical model with the FEM based numerical model of the axisymmetric bending of circular sandwich plates. Also, the paper describes equations of the circular symmetrical sandwich plates bending with isotropic face sheets and the nonlinear elastic core material. The method of constructing an analytical solution of nonlinear differential equations has been described. ...

In this paper, mechanical buckling analysis of composite annular sector plates with bean shape cut out is studied. Composite material sector plate made of Glass-Epoxy and Graphite-Epoxy with eight layers with same thickness but different fiber angles for each layer. Mechanical loading to form of uniform pressure loading in radial, environmental and biaxial directions is assumed. The method used...