Abstract
For decades, alternative fuels have been studied to further engine efficiency and lower combustion emissions. Of these fuels, biodiesel, alcohols, and ethers have shown advantageous benefits of improved mixing capability or reduced combustion emissions. Ether fuels consist of a range of C-O-C chain lengths that offer various noteworthy fuel properties such as fuel oxygen content and cetane number. In this work, oxymethylene dimethyl ether (OME3) and diesel are used as neat and blended fuels on a single-cylinder high compression ratio engine. Four test fuels are investigated in this work; baseline diesel, two diesel/OME3 blends, and neat OME3 fuel. Engine tests are conducted at an engine load of 6 bar and the intake oxygen concentration is modulated via EGR to realize the resulting engine performance, stability, and exhaust emissions among the test fuels. The results show that blending OME3 fuels with diesel is an effective technique to reduce soot emissions with minimal effect on NOx emissions. Moreover, neat OME3 was capable of emitting low NOx and soot emissions with a lower EGR amount than that of diesel-blends, mitigating negative combustion implication of EGR at high levels.
