Theoretical and Experimental Analysis of Engine Performance and Emissions Fuelled with Jojoba Biodiesel

Abstract

Over many decades, isolated regions (e.g., islands, rural and remote areas) have heavily relied on diesel engine for producing power and energy. However, due to depleting fossil fuels and concerning emissions, biodiesels could be the substitute for diesel in power generation sectors. This study developed a single-zone thermodynamic model to predict the engine performances such as brake power (BP), torque, brake thermal efficiency (BTE), brake-specific fuel consumption (BSFC) and ignition delay (ID) times for diesel and jojoba biodiesel. The experiments were conducted on a fully automated, 4-cylinder, 4-stroke, liquid-cooled direct injection 3.7-L diesel engine fueled with diesel (D100) and three jojoba blends (JB5, JB10, and JB20) to validate the model. The performance simulation results agreed with experimental data for all tested fuels at 1200 to 2400 rpm speed and 25%, 50%, 75%, and 100% loading operation. The minimum error (3.7%) was observed for BP for D100 at 2000 rpm and 100% load, and the maximum error (19.2%) was found for JB10 at 1200 rpm and 25% loading operation. As load increases from 25 to 100%, the BSFC and torque difference between diesel and JB20 decreases from 10 to 6.5 and 9 to 6%, respectively. A shorter ID time was observed in JB5 compared to JB10 and JB20. Furthermore, a significant reduction was observed in CO (7.55%) and HC (6.65%) emission for JB20 at 25% and 1200 rpm compared to diesel fuel; however, NOx emission was increased up to 10.25% under any given conditions.

Keywords

• diesel engine
• single-zone model
• jojoba biodiesel
• ignition delay
• emissions