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When air flows unsteadily in an internal combustion engine through its inlet pipe, chambers and valves, some effects such as friction and inertial forces have direct influence on the volumetric efficiency of the system. The work in this paper aims to investigate numerically and experimentally the pulsating phenomena present in an intake pipe of an internal combustion engine and to discuss the intake jet flow predictions through the novel implementation of a low Mach number preconditioned density-based method, including the three-dimensional modelling of the inlet valve, the inlet pipe and the pulsating effects. The inlet valve movement promotes moderate values of Mach numbers during its opening phase. After the inlet valve closes, the flow is abruptly restricted and a series of pressure waves propagate through the fluid at low Mach numbers. Although the low Mach number preconditioned density-based method is very attractive in this case, the study of the pulsating flow in the internal combustion engine intake systems has not been performed using this method, probably owing to robustness issues and simulation effort. The pressure-based methodology is widely used and, generally, the inlet pipe and pulsating effects are not included in the threedimensional fluid dynamics simulation. In order to verify the accuracy of the numerical solution, the results are compared with experimental data collected from a bench constructed specifically for this purpose. The numerical results were satisfactory for the amplitudes and the resonance frequencies in the air intake system. Also, different aspects of the jet flow inside the cylinder are shown and discussed.

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In this work is proposed the design of a dynamometer based on Foucault's Current Break for the evaluation of torque and power provided by a Savonius wind turbine model in a wind tunnel. The applied measurement system is of the open source type using the Arduino platform. For the reaction force metering a load cell with converter and amplifier H711 was used as well as a photoelectric sensor with resolution of one pulse per turn for the rotation measurement. Equations available in the literature were used to estimate the wind turbine performance parameters for the dynamometer sizing. The wire applied for magnetic flux generation in the coils is AWG24, to support an electrical current rating of 0.5 A and a voltage of 1.0 V. The coils size are 3.1 cm of diameter and 3.0 cm of length. Two coils were applied in order to satisfy the wind turbine demand. As a result, the dimensional characteristics of an eddy current brake able to measure a power of up to 0.5 W, generated by a Savonius wind turbine, were obtained, with uncertainty of measurement about 0.01 W, being adequate for the analyzed turbine.