NANOPARTICLE EMISSIONS FROM DIMETHYL ETHER COMBUSTION IN A COMPRESSION IGNITION ENGINE

摘要

Dimethyl ether (DME) has been identified as a promising renewable fuel for use in compression ignition (CI) engines. When produced from renewable sources, it has the highest well-to-wheel energy efficiency and lowest greenhouse gas emissions of any biofuel currently available [1]. The high cetane number (>55) and high volatility of DME make it ideal for CI engines. DME’s lack of carbon-carbon bonds produces no soot through conventional pathways during combustion [2]. Therefore, it is widely assumed that DME engines will meet U.S. particulate matter regulatory standards for vehicles without requiring a diesel particulate filter. However, nanoparticles emitted from combustion may still be emitted originating from the engine lubricating oil or from fuel lubricity additives required to protect fuel system hardware. This study examines nanoparticle emissions from DME operation in a diesel engine as a function of lubricity additive concentration in the fuel. Our work tested the hypothesis that lubricity additive increases semivolatile nanoparticle concentration in the exhaust.