An Hybrid FE/SEA Approach for Engine Cover Noise Assessment

In this paper a deep numerical analysis on an internal combustion engine’s cover is carried out. An Hybrid numerical model approach to evaluate the acoustic performance of engine's cover, has been used. The Hybrid model is composed of two numerical models: FE and SEA models. The model FE patterns the structural system, whilst model SEA patterns the acoustic environment. As main excitation an experimental data has been used for two considered engine conditions. The comparison in terms of sound pressure levels between the experimental and FEM/SEA analysis results shows a very good agreement, in the whole investigated frequency range. The obtained results encourage to use the numerical model for further investigations aimed at the improvement of its acoustic performances. The implemented numerical procedure can be applied successfully not only in automotive field but also in all problems where material acoustic performances, is due

Experimental and Numerical Validation of an Automotive Subsystem through the Employment of FEM/BEM Approaches

Abstract In this paper a deep numerical analysis on an internal combustion engine cover is carried out. A hybrid numerical model has been used to evaluate the acoustic performance of engine cover. The Hybrid model is composed of two numerical models: FE (Finite Element) and BEM (Boundary Element Method) models. The FE model patterns structural system, whilst BEM model patterns fluid environment. The main aim of the present work is to characterize, through the employment of numerical simulation, the acoustic performance of the engine cover by using the NR (Noise Reduction) parameter. The numerical frequency response analysis has been implemented using acoustic impedance experimental data, measured for four different thicknesses of sound proof material forming the cover system. The spectrum of acoustic impedance has been evaluated in near field with a sophisticated probe, pressure-velocity probe (p-v probe). The analysis of the obtained results have highlighted the weaknesses as regards sound attenuation of the cover system and possible further improvements of cover system acoustic performance

Capacitance-to-Digital Converter for Operation Under Uncertain Harvested Voltage down to 0.3V with No Trimming, Reference and Voltage Regulation

In Paper 5.2, the National University of Singapore and Politecnico di Torino present a capacitance-to-digital converter (CDC) for direct harvester-powered low-cost systems, showing a 7-bit ENOB down to 0.3V at 1.37nW power without any external reference or voltage-regulation requirements

Sensitivity Analysis and Correlation Experimental/Numerical FEM-BEM for Noise Reduction Assessment of an Engine Beauty Cover

Abstract In this paper a deep analysis on an internal combustion engine's beauty cover is carried out for identifying the best material for Noise Reduction improvements.The paper is organized as follows: • Experimental modal analysis and comparison with the FEM simulation • Experimental test on Noise Reduction assessment by using a novel experimental set up with a Pressure/Velocity Sound Intensity • Numerical Boundary Element Analysis for computing the Noise Reduction on the engine cover • Comparison between the experimental and BEM simulation The comparison of the experimental and FEM/BEM analysis results show a very good agreement in all investigated frequency range. The obtained results encourage to use the numerical model for further investigations aimed at the improvement of the acoustic performances. The implemented numerical procedure can be applied successfully not only in automotive field but also in all problems where material acoustic performances is due