Application of clean gaseous fuels in compression ignition engine under dual fuel mode: A technical review and Indian perspective

The rapid increase in energy demand and the fast depleting environment stresses the exploration of renewable and clean energy sources. Both biogas and hydrogen are considered clean and renewable fuels, and their effective utilisation in engines could reduce harmful emissions. The present review comprehensively investigates the influences of biogas and hydrogen on the performance, combustion, and emission of the compression ignition engine operating under dual fuel mode. In addition, Indian governmental policies related to biofuels are also discussed briefly. The present review showed that biogas utilisation reduces brake thermal efficiency, volumetric efficiency, and exhaust gas temperature, whereas brake-specific fuel consumption increases. Biogas introduction also reduces nitrogen oxides and smoke emissions with an increase in hydrocarbon and carbon monoxide emissions. The review shows that hydrogen supplementation results in better performance at high and moderate loads due to suitable fuel characteristics of hydrogen. The zero-carbon nature of hydrogen reduces all the carbonbased emissions from the climate change perspective. The increase in hydrogen proportion results in the escalated emission of oxides of nitrogen (approximately 30-60%) contrasting to diesel mode by virtue of higher incylinder temperature. Additionally, a detailed study is also presented on the bottlenecks in hydrogen application for dual fuel mode.

Automated summary

The study indicates that utilization of biogas decreases efficiency and exhaust temperature of compression ignition engines, but increases specific fuel consumption; hydrogen supplementation shows better performance at high and moderate loads with zero carbon emissions, though it leads to an increase in nitrogen oxide emissions as hydrogen proportion rises. Bottlenecks in hydrogen application for dual fuel mode are also discussed in detail.