Investigation of the Effects of JP-4 Addition to Biodiesel-Diesel Blends on the Performance Characteristics of a Diesel Engine

In this study, the effects of JP-4-biodiesel-diesel blends and engine operating parameters on the performance characteristics of a diesel engine were investigated. The experimental tests were performed on a four-cylinder DI diesel engine. The Mixture-RSM method was applied to develop the mathematical models based on the experimental data. The results showed that the fitted models could be properly applied to predict the performance characteristics of the engine. According to the results, the brake power and torque decreased with increasing the biodiesel amount in the fuel mixture due to the lower energy content and higher viscosity of biodiesel than diesel fuel No.2. However, the brake power and torque increased slightly with increasing JP-4 in the fuel blend. The results also indicated that the BSFC increased with the higher proportion of biodiesel in the mixture at all engine speeds. The results indicated that there was no considerable difference in BSFC values while JP-4 was added to the fuel mixture, especially at higher engine speeds. Moreover, the difference of brake power values for fuel blends included biodiesel and neat diesel decreases at higher engine speeds due to the positive role of oxygen content in the molecular structure of biodiesel. Based on the results, brake power and torque increased at the higher engine load as a result of higher temperatures and better combustion conditions. Moreover, JP-4 caused an improvement in brake thermal efficiency compared to biodiesel, especially at lower and medium engine speeds. Generally, it is indicated that the application of JP-4 can improve engine performance.