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Nowadays, NVH aspects in automotive sector are becoming very important. Components have to respect, other than strength targets also acoustic targets, in a way of reduce noise emission of the full vehicle. While vibration aspects have been sufficiently explored by virtual methodology but also by experimental one, the same it is doing, in recent years, for Noise aspects. Automotive engine manufactures are implementing CAE technology and methodology to simulate the acoustic characteristic of components and to optimize geometry, material and others parameters in order to match customer acoustic targets. This paper tell about numerical methodology to estimate the acoustic vibration of an Intake Manifold component and how to use that methodology to reduce noise radiation. Vibroacoustic analysis for different Intake Manifold are going to be presented, showing results and how they are managed to match customer targets

This paper intends to describe spray predictions using CFD technologies for spray formation and evolution on fuel blend. Spray formation was simulated in ANSYS CFX using a Lagrangian model. The primary breakup model used in this study is a variation of the well-known BLOB method. The Cascade Atomization Breakup (CAB) and Modified Cascade Atomization Breakup (MCAB) models for secondary breakup were used. Simulations using different Rosin Rammler distributions were carried out. N-Heptane was used as reference fuel for experimental tests. A high degree of consistency between experimental data and numerical analysis for spray propagation characteristics was found. The methodology has been developed on Heptanes, aiming to extend the methodology to other fuels, i.e. ethanol.

In recent years, automotive engine manufacturers are increasingly focusing their attention on noise generated by plastic air intake manifolds (AIMs). Due to their lower density and stiffness, some deficiencies in terms of acoustical properties have been observed for plastic intake systems compared to metallic manifolds. In this framework, it seems to be very important to address not only the issue of reducing inlet noise, but also noise radiated via the coupled fluid-structure interaction. In this work three AIMs, a baseline and two modified models, nominally having equal breathing performance, have been analyzed and compared. The modified ones presented ribs and stays for strengthening the structure. The analyses were performed with concurrent experimental and numerical validated procedures.