Bie model of periodic diffraction problems in optics

Optical diffraction on a periodical interface belongs to relatively lowly exploited applications of the boundary integral equations method. This contribution presents a less frequent approach to the diffraction problem based on vector tangential fields of electromagnetic intensities. The problem is formulated as the system of boundary integral equations for tangential fields, for which existence and uniqueness of weak solution is proved. The properties of introduced boundary operators with singular kernel are discussed with regard to performed numerical implementation. Presented theoretical model is of advantage when the electromagnetic field near the material interface is studied, that is illustrated by several application outputs.Web of Scienc

Tangential fields in mathematical model of optical diffraction

summary:We present the formulation of optical diffraction problem on periodic interface based on vector tangential fields, for which the system of boundary integral equations is established. Obtained mathematical model is numerically solved using boundary element method and applied to sine interface profile

Tangential fields in optical diffraction problems

summary:Optical diffraction for periodical interface belongs to relatively fewer exploited application of boundary integral equations method. Our contribution presents the formulation of diffraction problem based on vector tangential fields, for which the periodical Green function of Helmholtz equation is of key importance. There are discussed properties of obtained boundary operators with singular kernel and a numerical implementation is proposed

Plasmon excitation in periodic multilayers: modeling by boundary integral equations

Optical diffraction is one of the few exploited applications of boundary integral equations. In this paper, a numerical model based on boundary integral equations (BIE) is applied to a periodic multilayer. We present possible implementations of a derived algorithm that enables solution, e.g., for over-coated profiles. We give our attention to optical systems producing plasmon waves, for which we study the influence of several structural parameters on the diffraction response. The results are compared with the classical rigorous coupled waves method (RCWM) method, and, the case of non-smooth interface is discussed.Web of Science42469768

Monotonic tension-torsion experiments and FE modeling on notched specimens produced by SLM technology from SS316L

The aim of this work was to monitor the mechanical behavior of 316L stainless steel produced by 3D printing in the vertical direction. The material was tested in the "as printed" state. Digital Image Correlation measurements were used for 4 types of notched specimens. The behavior of these specimens under monotonic loading was investigated in two loading paths: tension and torsion. Based on the experimental data, two yield criteria were used in the finite element analyses. Von Mises criterion and Hill criterion were applied, together with the nonlinear isotropic hardening rule of Voce. Subsequently, the load-deformation responses of simulations and experiments were compared. Results of the Hill criterion show better correlation with experimental data. The numerical study shows that taking into account the difference in yield stress in the horizontal direction of printing plays a crucial role for modeling of notched geometries loaded in the vertical direction of printing. Ductility of 3D printed specimens in the "as printed" state is also compared with 3D printed machined specimens and specimens produced by conventional methods. "As printed" specimens have 2/3 lower ductility than specimens produced by a conventional production method. Machining of "as printed" specimens does not affect the yield stress, but a significant reduction of ductility was observed due to microcracks arising from the pores as a microscopic surface study showed.Web of Science141art. no. 3