Experimental investigation of a single cylinder diesel engine as a hybrid power unit for a series hybrid electric vehicle

Performance and emission testing, for a single cylinder, four-stroke diesel engine, have been experimentally performed to determine the optimum operation conditions for this engine when used as a hybrid power unit (HPU). The studied operation parameters included; Brake Specific Fuel Consumption (BSFC), exhaust emission (NO_x, CO, CO₂ and O₂) and engine life. The results indicate that the lowest BSFC of the engine is found when the engine runs around 1 kW charging load when the engine speed ranged between 1900 rpm-2700 rpm. As the speed of the engine is maintained constant, the minimum level of BSFC is below 300 g/kW.hr at around 1900 rpm. The engine best operation conditions, for low emission, are found at engine speed around 2500 rpm. It was found that the oxides of nitrogen remain within the acceptable level (below 180 ppm) for such a diesel engine.