Evaluation of the Performance Curves of the 4-Stroke, Spark-Ignited, Single-Cylinder Engine Altered to Consume Ethanol

Objective: To conduct tests on the B4T-5.5 hp spark-ignition engines (Otto cycle) with conventional fuels (types of gasoline) and, after modification, to test with renewable fuels (Ethanol) on the dynamometer in the engineering laboratory of Branco Motores Ltda., following SAE J1995 and SAE J1940 standards. Analyze the power and torque curves for each tested fuel. Theoretical framework: Utilizing the literature through research in books, dissertations, articles, and standards. Method: This study involves the performance of a gasoline engine converted to ethanol (renewable fuel) through quantitative research and the evaluation of test results on the 5.5 hp single-cylinder 4-stroke spark-ignition engine (B4T model) with each proposed fuel in the research. Results and Conclusion: During the analysis, the necessary values were measured to create the power and torque curves using different types of national fuels. The spark-ignition engine was connected to a dynamometer and tested with regular gasoline (Type C with 27.5% ethanol content), premium gasoline, podium® gasoline, and anhydrous ethanol 95% (the gasoline engine was modified to operate with ethanol). In the case of the renewable fuel, ethanol, the results for the spark-ignition engine (Otto cycle) showed an increase of 0.48 hp in power and 0.11 kgf.m in torque compared to gasoline. The ethanol-powered engine is a viable alternative and is considered a clean energy source when compared to traditional fuels (such as gasoline). Research Implications: Issues such as sustainability, renewable energies, environmentally friendly fuels, greenhouse gas emissions, and concerns about the environment have become increasingly common and evident in the global market. This reflects a global concern for environmental preservation and the future of the planet. For academia, the constant search for new or alternative sources will always be a challenge. Originality/Value: The proposal of an ethanol engine contributes to the reduction of pollutant gas emissions and environmental damage because ethanol, derived from sugarcane, absorbs carbon monoxide and carbon dioxide during the plant's development. This attenuates emissions since, during the ethanol burning process, the gases are only returned to the atmosphere (carbon and derivatives), unlike the burning of fossil fuels, which adds more gases to the atmosphere. Another point is that it provides an additional option for end consumers.