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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.

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.