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This manuscript focuses on devising a Tellurite-filled circular-timbered PCF that shows considerably highly birefringent and nonlinear characteristics. The impacts of numerous design parameters, such as birefringence (Br), nonlinear coefficients (NLC), confinement loss (CL), effective mode area (EMA), dispersion, numerical aperture (NA), etc. of the fiber are extensively inspected employing the commercially accessible and simulationfriendly COMSOL Software. Besides, the pertinent modal properties of the modeled fiber are rigorously characterized by operating the full-vector finite element method (FEM) with a perfectly matched layer (PML) boundary condition. The simulated findings affirm that the developed fiber exemplifies an ultra-high Br and NLC of 0.0924 and 18900 W-1Km-1 consecutively, at the operational wavelength of 1.55µm. Notably, the offered PCF also reveals a relatively lower CL, a negative-sloping dispersion and a higher EMA at the same wavelength. The pragmatic execution of the modeled fiber is expected to be doable applying the existing fabrication approaches and it can be applied in miscellaneous identical optical domains, namely polarization retention in long-distance communications, optical switching, sensor and laser layout, supercontinuum generation for frequency metrology and so forth. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents modelling techniques for achieving convergent and accurate solutions in simulating quasi-static indentation of closed-cell aluminium foams and sandwich panels with aluminium foam core using the commercial finite-element software ABAQUS/Standard. Various indenters are utilised: hemispherical indenters of 10, 15 and 20mm diameter, a 16-mm cylindrical flat punch, and a long flat punch. The material parameters are established by comparison with the previous experimental results in uniaxial compression. Experimentally-observed tearing of the cell walls is accounted for in the simulations by introducing element failure and deletion criteria. Stress and strain analysis of the results reveals that foam failure occurs where cell tearing takes place. This occurs at critical tear energy and shear strength, independent of indenter size. The resulting load–displacement curves correlate closely with experimental results. The quasi-static indentation of sandwich panels of aluminium foam cladded with aluminium skins is also simulated for hemispherical indenters of diameter 5–20mm. Cell tearing does not occur until the point of failure and thus, is not accounted for in the simulations. The effect of the skin strength on the stiffness, strength and energy absorption of the panels is elucidated. A particular emphasis is placed on the material formulation for the foam core which would ensure convergence and reliable predictions. [Copyright &y& Elsevier]