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The growing global need for energy and the aggravation of vehicular pollution, associated with a highly competitive market, demand fast and less expensive solutions to develop engine technologies. Numerical simulation has been an effective tool to help meet these needs, as it shortens the time and cost of current engine research. In this scenario, 1-D numerical model has been widely and successful used, presenting excellent results generally with errors around 5% in comparison with experimental data. In this work, the main performance parameters of an in-line four-cylinder SI engine is analyzed through a 1-D simulation using the GT-Power code. A full-scale engine model is set up, which is later calibrated by comparing with experimental data. The numerical methodology is carefully discussed and the methods regarding engine valve diagram and geometrical boundary conditions are also presented.

This paper applies numerical models to simulate the Onset of Knock (OK) in a commercial automotive spark ignition engine. Results from different models were compared with different knock detection methods to verify the best agreement. Despite being widely studied and reported in the literature, avoiding knock still poses a challenge to engine efficiency improvement and it is the focus of many new technologies. Knock detection methods rely on measurements of incylinder pressure or engine vibrations to determine the onset of knock, while some 0D predictive models are deduced from experimental data and correlations involving the critical parameters related to the knock phenomenon. Although 0D predictive models are easy to apply and calculate, the initial formulation and the different experimental conditions used to create each model often result in different numerical formulations.

The transportation sector is responsible for 24% of CO2 global emissions and great effort has been made by the scientific community to replace the use of fossil fuels with renewables. Brazil has committed to implement all obligations provided in COP26 seeking carbon neutrality in the set of economic activities. In this regard, Brazil has agreed in reducing GHG by 50% until 2030. Flexfuel technology was introduced in the Brazilian market decreasing fuel conversion efficiency due to the use of an intermediary compression ratio value, lower in comparison with the best value for engines exclusively fueled with ethanol and higher for gasoline. According to data published by INMETRO, flexfuel engine consumption has increased around 6%. Many European countries have been pointing to the electrification of the light vehicle as a solution to mitigate GHG, which is neither best nor a feasible solution for the future of Brazilian mobility.