Investigation of NG-diesel dual fuel engine performance, combustion, and emissions

Abstract This study experimentally investigates a natural gas-diesel dual-fuel naturally aspirated engine's combustion and emissions under low to high load and constant engine speed. The natural gas is supplied with constant pressure at the intake manifold through an air-gas mixer. A mechanical high-pressure fuel injection pump automatically controlled the diesel fuel. Results indicate that using natural gas reduced diesel fuel consumption, CO 2 , smoke, and NO x emissions, but increased CO emission with different values according to engine load. As well, in-cylinder pressure and heat release rate are influenced by using natural gas and changing engine load. These results differ from prior research; therefore, this study could be a basis for future research on hydrogen-natural gas blends.