Ricerc@Sapienza

This chapter provides a review of the basic ideas at the core of the Computational Singular Perturbation (CSP) method and the Tangential Stretching Rate (TSR) analysis. It includes a coherent summary of the theoretical foundations of these two methodologies while emphasizing theirmutual interconnections. The main.

This chapter provides a review of the basic ideas at the core of the Computational Singular Perturbation (CSP) method and the Tangential StretchingRate (TSR) analysis. It includes a coherent summary of the theoretical foundations of these two methodologies while emphasizing theirmutual interconnections. The main.

During the design phase of tunnel constructions in urban areas, advanced finite element models are a convenient tool to predict and reduce the impact of settlement on the surface infrastructure. These models can only deliver realistic results if, on the one hand, the level of detail of the model is high enough and, on the other hand, the model parameters have been well calibrated. Since soils are subjected to large parameter uncertainties, the determination of the model parameters is quite challenging.

This paper presents a novel numerical approach to simulate H-plane rectangular-waveguide microwave circuits considering a reduced quasi-2D simulation domain with benefits for computational cost and time. With the aim to evaluate the attenuation of the full height 3D component, we propose a modified expression for the waveguide top/bottom wall conductivity. Numerical 2D simulations are validated against results from full wave 3-D commercial electromagnetic simulator.

In this work, the thermal potentialities of insulation panels made of cork have been explored by means of a numerical approach based on experimental data. A comparative analysis between the panel in unaltered state, and then covered with an innovative shield coating (COIB 250®) was carried out. In addition, a defect simulating an inner detachment of the panel was fabricated to understand its behaviour during a daily solar thermal load. The site was selected ad hoc to avoid any shadow cast effect on the panel itself and any conduction phenomenon from the surrounding area.

This work explores the potentialities of combining a multi-layer eco-friendly panel with a phase change material coating. Although the work is based on a numerical approach performed by COMSOL Multiphysics® computer program, it can be considered as rigorous, robust, and optimized since the most important parameters added to the model were experimentally evaluated. The scientific soundness was guaranteed by a comparative analysis performed in two different times.

A closed-form model for the forward scatter radar (FSR) signal is presented with the goal to overcome the far-field (FF) limitation of the commonly used models. The proposed Fresnel closed-form (FCF) model, based on an approximation of the Helmholtz-Kirchhoff electromagnetic theory, correctly represents the received field of rectangular metallic targets crossing the baseline either in the short range or long range of the FSR transmitter and receiver.

This paper critically examines the numerical predictions of the seismic site response of both ideal and real cases as obtained by means of mono- and multi-dimensional Finite Element (FE) approaches. Ideal case-studies are first considered, aiming at validating the adopted numerical approach against existing analytical or simple numerical solutions. Then a three dimensional model of the Bovino urban area, located in southern Italy, was generated taking into account the real site conditions.

With a view to gaining an in-depth assessment of the response of particleboards (PBs) to different in-service loading conditions,
samples of high-density homogeneous PBs of sugarcane bagasse and castor oil polyurethane resin were manufactured and
subjected to low velocity impacts using an instrumented drop weight impact tower and four different energy levels, namely
5, 10, 20 and 30 J. The prediction of the damage modes was assessed using Comsol Multiphysics. In particular, the random