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This work compares the accuracy of in-cylinder pressure and apparent heat release rate (AHRR) diagrams to the experimental data and the use of different chemical kinetics models applied to the GT-Power® software. The engine computational model is based on a naturally aspirated diesel engine with three cylinders, one of them modified to operate with hydrous ethanol with port fuel injection and HCCI combustion achieved with hot exhaust gas recirculation (EGR) of the Diesel cylinders. Operating points chosen to perform the comparison to experimental tests were 1800 rpm, 300 kPa of indicated mean effective pressure and fuels with 10% and 20% of water-in-ethanol by volume. The kinetic mechanisms for ethanol oxidation evaluated were the detailed NUI Galway and a Skeletal model based on it. With either model, cylinder pressure diagrams were not very different from the experimental values. The detailed mechanism was, on average, 9 times slower to process each case than the Skeletal mechanism.

Electrical energy generators often use commercial diesel engines as a source of mechanical power at a fixed rotational speed. While the frequency of the grid cannot be modified, electric generators demand reciprocating engines to operate not always at their best efficiency range. By the use of a generator capable of running on different speeds and an electronic system that controls the output frequency, it is possible to operate the engines at their best efficiency load points. This paper describes the development of a variable speed diesel fueled electric generator with permanent-magnet high-efficiency synchronous generator. It was used a 1-D computational code to build a map through a mean-value model that combines speed and load to achieve the required power with the best engine efficiency. The generator set was instrumented whilebrake and indicated data were obtained in order validate the computational model.

Internal Combustion Engines (ICE) have their use highly disseminated in the most diverse operations. Exhaust gaseous emissions and fuel consumption have been on the scope for decades and therefore the necessity for research on more efficient and lower exhaust emission engines has increased. Considering the cost of equipment and software to develop ICE, the use of computational models is a key strategy to evaluate the behavior of the powertrain/vehicle and lower the instrumentation cost. In this sense, the present work shows the development of an algorithm to obtain a high-resolution crank angle (CA) position of an engine by means of a toothed wheel instead of a high-resolution incremental or absolute encoder. As a result, it enabled the analysis of performance and combustion parameters based on in-cylinder pressure signals acquired through a piezoelectric pressure transducer and the angular position of the crank train referenced by a Hall Effect sensor.

The current quest for clean and renewable fuels has prompted the appearance of several bio-mass fuel alternatives. Ethanol is a renewable biofuel obtained from different agricultural crops. The main production process to obtain anhydrous ethanol consists of crop production, mashing and cooking, fermentation, distillation and chemical dehydration. Some attractive characteristics of ethanol as a clean energy source is the CO2 absorption through photosynthesis during the crop plantation phase and positive ethanol life cycle energy balance. Even though, ethanol production cost is still relatively high when compared to fossil fuels. Knowing that a large energy amount is spent in the distillation phase, the use of hydrous ethanol as fuel, with high water content, can be economically attractive. This paper compares the use of high water-in-ethanol volumetric content fuel, varying from 5% to 40%, in a naturally aspirated 0.668-L single-cylinder port-fuel injected spark-ignited engine.