EXPERIMENTAL AND REGRESSION ANALYSIS OF COMPRESSION IGNITION ENGINE POWERED BY DIESEL SURROGATE FUEL FROM USED LUBRICATING OIL USING MICROWAVE PYROLYSIS

Abstract

Fossil fuels are depleting rapidly, and the search for alternative fuels has become inevitable. The researchers investigated the usage of surrogate fuels for internal combustion engines due to the high demand for diesel fuel in all sectors. Diesel surrogate fuels (DSFs) from used lubricating oil seem to be a solution for the future. The disposal of used lube oils poses a major environmental issue that affects the entire planet. This study aims to anticipate the exhaust emissions, brake-specific fuel consumption (BSFC), and brake thermal efficiency (BTE) of a compression ignition engine powered by blends. The blends used are B10 (DSF10% + diesel 90%), B20 (DSF20% + diesel 80%), B30 (DSF30% + diesel 70%), and B50 (DSF50% + diesel 50%) of DSF with diesel through microwave-assisted pyrolysis of used lubricating oil as fuel. Experimental findings were applied to predict each condition's performance characteristics. To estimate the performance characteristics, regression analysis was employed using experimental data in Microsoft Excel and Design Expert-12 software. The experimental data were compared to the simulated data. It was observed that fuel obtained from used lubricating oil using microwave-assisted pyrolysis could be used to power diesel engines without making any changes to the existing engines because the chemical characteristics of the diesel surrogate fuel were almost identical to those of diesel. The BTE of a compression ignition engine with DSF was close when compared to diesel up to full loading condition. At 1.924 kW brake power, the DSF30% has a higher efficiency than the other three blends. It was also observed that the rise in brake power also raises BSFC, thereby lowering thermal efficiency.