Dual Fuel-Engine Interactions: A Review of the Impact of Fuels on Internal Combustion Engine Emissions and Performance

Petroleum-based fuels are finite, and the urgent need for alternative, non-petroleum fuels for internal combustion engines (ICEs) has become increasingly evident. In recent years, the automotive industry has faced increasing pressure to reduce the harmful emissions produced by direct-injection diesel engines. To address this challenge, various strategies have been explored, among which the 'dual-fuel concept' has emerged as a promising approach for controlling both nitrogen oxides (NOx) and soot emissions, even in existing diesel engines. One such strategy involves the incorporation of gaseous fuels with conventional diesel. These gaseous fuels, which typically possess high octane numbers and exhibit gasoline-like characteristics, are more resistant to auto-ignition. The primary goal of dual-fuel operations with diesel and gaseous fuels is to reduce emissions of particulate matter (PM) and NOx. The main objective of this study is to provide a comprehensive review on the effects of gaseous fuels, such as hydrogen gas, natural gas (NG), biogas, liquefied petroleum gas (LPG) and syngas in dual-fuel operation with diesel. The review focuses on comparing these effects to those of conventional diesel combustion in terms of engine emissions and performance. Understanding the synergy of the dual-fuel concept helps to revolutionize ICE technology, highlighting its potential economic benefits and contributions toward more sustainable and environmentally friendly transportation solutions.