Search results for "COSTRUZIONE"
showing 10 items of 669 documents
Finite Element Method Analysis of a Spur Gear with a Corrected Profile
2007
The difference between the stress value calculated by a two-dimensional finite element model of spur gears and those obtained by the rules in ISO 6336 was evaluated. Hertz theory, which provides information on the extension of the contact area and the maximum value of the contact pressure, was used to choose the dimensions of the elements. The mesh was created using the stress analytical solution relative to a model consisting of two cylinders in contact. Analogous optimization was executed for the mesh of the teeth feet; a mesh of 15 elements was considered optimum, because it minimized the difference to 0.5 per cent in the bending stress calculation. Stress values, obtained using the fin…
Il secondo concorso per il Parlamento di Ernesto Basile. Criteri di modellazione e stampa 3D
2021
Il progetto per il secondo concorso per il Parlamento di Ernesto Basile, premiato nel 1890, si configura come opera di grande pregio nella produzione dell’architetto palermitano e come preziosa testimonianza per la storia dell’architettura e la storia del disegno. I disegni originari, conservati presso la Dotazione Basile del Dipartimento di Architettura dell’Università degli Studi di Palermo, già oggetto di studio e di analisi, sono stati utilizzati per una ulteriore elaborazione finalizzata alla realizzazione di un modello in stampa 3D in scala 1:100 che sarà in esposizione permanente presso la Dotazione stessa. Il presente studio ne descrive il processo metodologico, i criteri di realizz…
Defect Detection in Additively Manufactured Components: Laser Ultrasound and Laser Thermography Comparison
2018
Despite continuous technological advances in additive manufacturing, the lack of non-destructive inspection techniques during the manufacturing process is a limit for the industrial breakthroughs. Additive manufacturing is mainly used in industrial sectors where the zero defect target is crucial. The inclusion of the integrity assessment into the additive manufacturing process would allow corrective actions to be performed before the component is completed. To this end, the development of in-process monitoring and processing techniques is of great interest.This work proposes and compares two remote non-destructive inspection techniques: laser ultrasound and laser thermography. The two techn…
Evaluation of crack-closure by second harmonic thermoelastic stress analysis
2022
The work illustrates a new experimental approach to evaluate crack-closure in samples undergoing Fatigue Crack-Growing. Crack-closure leaves a peculiar signature on both amplitude and phase of the harmonic of the temperature signal at twice the loading frequency (Second Harmonic), due to the periodic nature of the internal elastic compression stresses. Thermoelastic Stress Analysis (TSA) is successfully applied to reveal such signatures on Single-Edge-Notched steel samples. A methodology is also proposed to evaluate the Crack-Opening-Load from temperature data. The work finally explores the influence of crack-closure on crack-tip identification and on the evaluation of the Stress Intensity …
Inspection of additive-manufactured layered components
2015
Laser powder deposition (LPD) is a rapid additive manufacturing process to produce, layer upon layer, 3D geometries or to repair high-value components. Currently there is no nondestructive technique that can guarantee absence of flaws in LPD products during manufacturing. In this paper a laser ultrasonic technique for in-line inspection of LPD components is proposed. Reference samples were manufactured from Inconel and machined flaws were created to establish the sensitivity of the technique. Numerical models of laser-generated ultrasonic waves have been created to gain a deeper understanding of physics, to optimize the set-up and to verify the experimental measurements. Results obtained on…
Voci dal passato. Fascismo, seconda guerra mondiale e ricostruzione nelle testimonianze degli abitanti della Valle dei Santi
2009
Theoretical and Experimental Comparison between the Resistance Components of a fast Catamaran in different Configurations
2009
The investigation performed by the Authors represents the most recent development of a research presented in [1] and [2], in which the geometrical solutions of the hull have been obtained through an optimization process, made by using the CFD numerical methods. The most important result of this optimization was the wave resistance reduction, which arrived up to 20% of the total initial resistance. In this further process the hull catamaran model has been built and tested at the towing tanks of the Universities of Naples and Trieste. The results obtained in the numerical process have been compared with the experimental ones and the reliability of the numerical results will be proved. Then th…
An analysis of interface delamination mechanisms in orthotropic and hybrid fiber-metal composite laminates
2007
Abstract The onset and propagation of interlaminar defects is one of the main damage mechanisms in composite materials. This is even more the case when considering layered materials comprising metallic laminae (typically Aluminium) and FRP laminae. Propagation of delamination mainly depends on the initial crack extension and its loading mode. This work presents some results of a combined analytical–numerical–experimental study on the onset and propagation mechanisms regarding interlaminar defects. Two cases have been analysed in particular, the first consisting of a glass-fibre reinforced epoxy resin laminate, and the second consisting of a hybrid laminate where a lamina of aluminium is lay…
Speculazione ed empiria: la Deduzione generale del 1800
2012
Jean-Luc Nancy e L'iperbole del finito
2013
The Editor's introduction to this monographic number. Wih a survey on the various essays and the outline of Nancy's ontological perspective as a possible key to read the author's work as a whole.