Design, fabrication and implementation of HE-OBCU-EGR emission control unit on CI engine and analysis of its effects on regulated gaseous engine emissions

Abstract

Adverse atmospheric conditions and health hazards originated due to the discharge of particulate matter (PM), hydrocarbons (HC), nitrogen oxides (NOx) and carbon monoxide (CO) are the fundamental challenges to the researchers working on diesel engine. The solution is to develop cleaner technologies to abate emissions from diesel engine exhaust. In this paper, a novel hybrid emission control unit composed of counter flow heat exchanger (HE), oil bath cleaning unit (OBCU) and exhaust gas recirculation (EGR), the combination abbreviated as HE-OBCU-EGR unit, was designed, fabricated and implemented on the exhaust manifold of Massey Ferguson (MF-260) tractor engine to reduce the regulated gaseous emissions. An experimental study was conducted to investigate the effects of HE-OBCU-EGR unit on the emissions of a four-stroke, three cylinder diesel engine equipped with an eddy-current dynamometer. The tests were conducted on engine speed of 1400 to 2000 rpm with an interval of 100 rpm at full load. The AVL DiTEST and AVL smoke meter were used to analyze the emissions including soot concentration (SC), pollution level (PL), filter smoke number (FSN), HC, NOx and CO. The results obtained with HE-OBCU-EGR unit revealed 44.9%, 29.2%, 26.3%, 42.9% and 24.8% reduction in SC, PL, FSN, HC and NOx emissions, whereas CO emissions were increased by 14.3% due to limited supply of oxygen from EGR. Results revealed that HE-OBCU-EGR unit may help to minimize the emissions of HC, SC, PL, FSN and NOx but is not suitable to control CO emissions. To minimize the emissions of CO, this technology can be superposed with turbocharger or supercharger to enhance the availability of O2 in the combustion chamber.