THE EFFECT OF OXYGENATE-IN-DIESEL BLENDS AND FISCHER-TROPSCH DIESEL ON PARTICULATE MATTER EMISSIONS FROM COMPRESSION-IGNITION ENGINES

摘要

The effect of oxygenates and Fischer-Tropsch (F-T) diesel fuel on particulate matter (PM) emissions was evaluated through a series of tests on a Cummins B5.9 6-cylinder diesel engine and a Acme Motori-ADX 300 single-cylinder diesel engine. Experiments were conducted with a fuel called Cetaner, which consists of 20% by volume monoglyme (CH{sub}3OCH{sub}2CH{sub}2OCH{sub}3) and 80% by volume diglyme (CH{sub}3OCH{sub}2CH{sub}2OCH{sub}2CH{sub}2OCH{sub}3), as well as a Fischer-Tropsch (F-T) fuel and dimethoxy methane (DMM) (CH{sub}3OCH{sub}2OCH{sub}3). For the tests with the Cummins B5.9 engine, PM mass emissions were measured with blends of Cetaner in diesel fuel ranging from 10% to 40% by volume. The addition of Cetaner resulted in lower PM emissions, with PM mass decreasing as Cetaner blend level increased. Reductions in PM of up to 58% were achieved with the addition of 40% Cetaner by volume. PM emissions reductions were also observed to correlate well with fuel oxygen content. For experiments conducted on the Acme Motori-ADX 300 engine, measurements were made of exhaust particle size distribution and number density using a scanning mobility particle sizer (SMPS). A baseline diesel fuel, F-T diesel, 20% by volume DMM in diesel, and 20% by volume DMM in F-T diesel were tested. Results indicate that the oxygenates and F-T diesel reduce exhaust particle number density and particle volume concentration, and can also cause shifts in particle size distribution at higher engine loads. Compared to the baseline diesel, F-T diesel and the DMM in diesel blend reduced calculated PM mass emissions by 24% and 48%, respectively. The largest reductions were observed for the DMM in F-T diesel blend, which produced an 82% reduction in particle mass concentration relative to the baseline diesel.