Optimization the Performance and Emission Parameters of a CI Engine Fueled with Aviation Fuel-Biodiesel-Diesel Blends

The determination of the optimum engine working conditions plays an important role in increasing engine performance and reducing exhaust emissions. The main objective of this study is to optimize the performance and emission characteristics of a CI engine fueled with aviation fuel-biodiesel-diesel blends at various engine speeds and loads using Mixture-RSM. According to the experimental tests carried on a 4-cylinder engine, the mathematical models were developed. Then, the optimization processes were defined as the six scenarios containing the consideration of performance or emission parameters or both of them. Scenario 1 shows that the higher percentage of diesel and jet fuel can improve the performance parameters of the engine; however, Scenario 2 shows that only higher percentage of diesel can improve the engine emission due to negative effect of biodiesel on the NOx emissions and negative impact of aviation fuel on the CO and HC emissions that limit the amount of biodiesel and aviation fuel in the fuel mixture. The results also show that Scenario 3 does not vary compared to Scenario 2. The optimized point for both of engine performance and emission parameters presented in Scenario 6 was calculated as D48.9B32.7J18.4 at 2526 RPM and full engine load to obtain 88.4 (kW), 337 (N.m), 255 (gr/Kw.hr), 0.0268 (%), 469 (ppm), 7.7 (%) brake power, torque, BSFC, CO, NOx, and HC emission, respectively.