Performance and emission analysis of hydrogen-fuelled compression ignition engine with EGR: a prospective approach towards clean mobility

The energy demand has still been fulfilled, primarily by fossil fuels globally. Hydrogen is the only carbonless fuel that can fulfil the energy demand without impacting the environment. In this research work, a variable compression ratio (VCR) CI engine with exhaust gas recirculation (EGR) is tested with hydrogen gas as a primary fuel. Initially, the diesel is used as a pilot fuel igniter to initiate the combustion process. Once the cycle is initiated, the hydrogen gas is supplied and controlled through port fuel injection at a pressure of 2 bar. The engine is operated at various compression ratios (12, 14, 16, 18) and different loads: 0% (0 kg), 25% (4 kg), 50% (8 kg), 75% (12 kg) and full load (16 kg), with and without exhaust gas recirculation. The results revealed that the brake thermal efficiency of the hydrogen-fuelled engine increased by 6.5% and a significant decrement in brake-specific fuel consumption (bsfc). The maximum cylinder pressure inside the cylinder is observed at 68 bar at 12 kg of load and 18 CR. The NOx emission is reduced by 49.4% by using the cold ERG method.