Performance and pollutant characteristics of an old generation diesel engine fuelled with dual-fuel diesel-dimethyl ether

Abstract

An old generation diesel engine running on dual-fuel dimethyl ether (DME) and diesel was tested for pollution reduction and performance enhancement. DME was pre-mixed with intake air using a single-port gaseous fuel injection system to replace 5% (DME5) and 10% (DME10) diesel. Study results show that the fuel economy improves when the engine operates with dual fuel. The brake-specific energy consumption reduces by 2.5% and 3.0% at full load condition and 4.5% and 5.1% at a medium speed of 1600 rpm on average for DME5 and DME10 compared to pure diesel case. The in-cylinder pressure, temperature, and vibration rate were evaluated to determine DME's effect on engine combustion. The impact of DME was noticeable as exhaust pollutants enhanced remarkably for NOx and smoke components. When the engine was fueled with DME5 and DME10, the specific particulate matter fell dramatically by 32.90% and 50.23%, NOx declined moderately by 8.66% and 20.39%.