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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.

The success obtained by use of Virtual Engine Modeling (VEM) in the design and development areas of fuel injectors generated a lot of interest from production and quality engineers to possess a similar tool related to spray vessel measurements. To respond to stringent PL6/EURO5 requirements it was decided to develop a Virtual Spray Vessel (VSV) tool capable of predicting spray patterns and perform droplet diameter analysis comparable to real-time Phase Doppler Analysis (PDA) results. The paper describes the analogies between VEM and VSV modeling and the specific new numerical approaches to obtain spatial spray data comparable to conventional mechanical measurement techniques and to perform droplet diameter analysis comparable to PDA data. The paper concludes with a series of comparisons of simulated and experimental data from virtual and real-time measurement vessels.

The paper presents the background physics of droplet coalescence phenomena and the basic research carried on the topic by interactive use of high-level 3-D numerical simulation tools and high-level optical visualization and measurement techniques. The presentation continues with the description of a new injector atomizer plate layout, which enables a physical coalescence control of the droplet population within the entire fuel spray. Finally are presented examples of the impact on exhaust emissions of the introduction the new atomizer plate with coalescence control by engine test bed experiments (steady state low load conditions) and vehicle tests (first cold part of the FTP-cycle).

Components of an automatized transmission system were improved by using techniques of finite element numerical simulation and topology optimization, in order to achieve mass saving and higher performance. Numerical simulations have being applied more frequently during the components design, once the models become more sophisticated, higher computational capacity is available and more precise material properties can be determined. In this paper, a good correlation between the simulation models and the experimental tests was achieved through the material properties determination by means of the impulse excitation technique. This impulse excitation technique consists of a non-destructive test for the dynamic elasticity modulus and material damping through the vibration natural frequencies. The test specimens are evaluated by an impulsive mechanical excitation and the response acoustic signal is collected by a microphone and processed in a conventional computer.

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.

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