Evaluation of Some Alternative Diesel Fuels for Low Emissions and Improved Fuel Economy

摘要

This paper reports on Ford's participation in the PNGV "Ad Hoc" Diesel Fuel Test program -Phase I. The purpose of this program was to assess the potential benefits of various fuel properties aimed at reducing engine-out emissions of NOx and particulates to meet LEV2 and Tier 2 emission standards. Four alternative fuels were evaluated using a Ford 1.2L DIATA diesel engine: 1) California Certification fuel (CARB), 2) low sulfur hydro-cracked fuel (LSHC), 3) LSHC fuel with a 15% Dimethoxy Methane blend (DMM), and 4) neat Fischer-Tropsch (FT100) fuel. Design of Experiments (DOE) and conventional techniques were used to evaluate the fuels at five speed and load conditions. Exhaust gas recirculation (EGR), injection rail pressure, and beginning of injection (BOI) timing were controlled during the tests. Steady-state engine performance, emissions, and cylinder pressure (combustion) data were recorded for each fuel. The results show that fuel properties can significantly affect diesel combustion and exhaust emissions by altering the ignition delay and the relative proportion of premixed and diffusion burning. The results also show the importance of proper engine/fuel calibration in order to take advantage of the fuel property benefits.