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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.

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.

The internal combustion engines development includes dynamometer tests in order to research and adequate components. The main advantages of dynamometer tests are the quick and reliable answers and a great number of possible thermal and mechanical loads, when compared to field tests on vehicle. The difficulty on the correlation between the results obtained on test beds with those obtained in the same engine on real utilization conditions is the disadvantage of this kind of test. This paper presents a development where cyclic tests on dynamometer test beds were used in order to obtain the oil consumption during the development of new piston ring projects. These cyclic tests were developed because the conventional dynamometer tests did not reproduce the results obtained for oil consumption in field tests. To elaborate these tests, a mathematical program was developed in order to make the correlation between engine tests on test beds and those tests run on vehicles.