Investigation of the Effects of Gasoline-Bioethanol Blends on Engine Performance and Exhaust Emissions in a Spark Ignition Engine

In this study; 95 octane unleaded gasoline and bioethanol were tested as fuel in a spark-ignition engine by blending bioethanol with gasoline in certain proportions (2%, 4%, 6%, 8%, 10%). Tests were carried out at five different engine loads for a constant engine speed of 2500 rpm. The variations in engine performance parameters (brake thermal efficiency, brake specific fuel consumption, brake specific energy consumption) and exhaust emissions (HC, CO, CO 2 and O 2 ) were investigated on the basis of test fuel and engine load. According to the test results, with the increase of bioethanol ratio in the blend, brake specific fuel consumption values ​​increased by 9.71% and brake thermal efficiency values ​​decreased by approximately 4.97% compared to gasoline. There was decrease in HC and CO emissions and an increase in CO 2 emissions with bioethanol addition.