Effect of cracked naphtha/biodiesel/diesel blends on performance, combustion and emissions characteristics of compression ignition engine

Utilization of biofuels has drawn attention of researchers for many years to face depletion of fossil fuels. The high viscosity and low heating value of biodiesel are main drawbacks of using it along with high NO_x emissions. Addition of ternary component to relax these drawbacks are widely considered. The focus of this study is to illustrate the effect of a novel ternary component to diesel-biodiesel blend on combustion characteristics, engine performance and emissions. This third component is cracked naphtha which is a low cetane/low octane fuel. Engine experiments were performed using a single cylinder, 4-stroke, air-cooled compression ignition (CI) engine. Different naphtha concentrations were considered. This included 5%, 10% and 15%. The engine performance results revealed that 10% and 5% are the maximum allowable percentages of naphtha to D100 and B30, respectively. A reduction in brake specific fuel consumption (bsfc) of 6.28% and 11.7% was achieved for 5% and 10% naphtha addition to diesel, respectively. Negligible effect was observed for naphtha on bsfc for B30–N5. Naphtha has decreased NO_x emissions for B30–N5 at all considered loads and for diesel-naphtha blends at high and medium loads. CO emissions have been reduced for diesel-naphtha blends, while for B30–N5, CO emissions was increased.