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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

In the current Brazilian air intake manifold market, most of the small car applications use the reinforced polyamide PA 6.6 GF30 as base material. The glass fiber (30%) guarantees the required mechanical resistance, necessary once the manifold is assembled on the engine and is subjected to considerable vibration levels. Air intake manifolds were developed using a new chemically recycled material recuperated from yarn production process, called Technyl ECO, which represents a reduction of 4.3 kg of CO₂ equivalent per 1 kg of polyamide produced. This material can replace the current one, once it has the same formulation (PA 6.6 GF30) and similar mechanical resistance. Moreover, it represents a cost saving up to 10% in the raw material. The air intake manifolds injected with the recycled material were subjected to the mechanical validation tests under severe conditions of accelerated aging at temperature of 140°C and thermal shock with abrupt temperature change from -40°C to 120°C.

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.

Several projects in engineering involve rotating parts submitted to bending loads, which can result in the material heating. This thermal load happens due to energy loss caused by the material damping. This heat source can be great enough to make the component reach high temperatures and, consequently, risk its performance or even its resistance. A theoretical approach, considering that part of the mechanical energy is converted to thermal energy, implies that the maximum temperature found in a uniform rotary beam is linear dependent with the rotating speed and is directly proportional to the square of the applied load. This work intends to present some results acquired from an experiment performed in a fatigue test machine and also validate the theoretical formulation. Stainless steel (316L) specimens were painted with matte black ink to improve their emissivity. The temperature was measured via a FLIR thermographic infrared camera.

The physical properties of ethanol make difficult the cold start of engines using only this fuel. The solution most adopted consists in the utilization of an auxiliary gasoline reservoir and the injection of this fuel when it is necessary. In this work, it is presented a new concept for the cold start system using gasoline injection that consisted in the use of a mini fuel rail, so called because of its compact layout that through the use of calibrated orifices allows the fuel injection as jets directly in the admission valves. It presents the CFD simulations, conducted to improve the system performance and the bench laboratory tests performed to evaluate the fuel distribution and to analyze the fuel jets.