NOx emission reduction using permanent/electromagnet-based fuel reforming system in a compression ignition engine fueled with pine oil

Abstract: In this experimental study, pine oil is identified as low viscous low cetane (LVLC) fuel for compression ignition engine replacing diesel. Numerous advantages of LVLC fuels include improved combustion due to favorable physical properties than diesel. This leads to reduced hydrocarbon, smoke and carbon monoxide emissions with improved thermal efficiency. However, utilization of pine oil as a drop in fuel is challenging, due to its low cetane index. This leads to higher nitrogen oxide (NO) emission due to prominent heat release rate. A novel fuel reforming system based on the principle of electrochemical liquid vortex ionization was used with permanent magnet/electromagnet to reduce NO emission with pine oil as base fuel. Electrochemical liquid vortex ionization system converts the fuel molecules to ions; this leads to enhanced atomization and faster air–fuel mixing process leading to lower ignition delay. A two-cylinder commercial CI engine was used for this experimental study. Performance, emission and combustion characteristics were studied for pine oil with and without ionization system at 3, 6, 9 and 12 kW power output and compared with diesel. According to engine test results, compared to diesel, brake thermal efficiency for pine oil is higher and further improved with ionization system. Emissions like smoke, hydrocarbon, carbon monoxide and carbon dioxide are reduced for pine oil in comparison with diesel and further reduce with the ionization system. Longer ignition delay with pine oil operation leads to higher NO emission compared to diesel. Nevertheless, the use of magnetic-based fuel reforming system reduces the ignition delay leading to lower NO emission. Graphical abstract: [Figure not available: see fulltext.].