Supplementary Fueling of Four-Stroke-Cycle Automotive Diesel Engines by Propane Fumigation

The art of supplementary-fueling Diesel-powered highway vehicles is reviewed. Some theoretical considerations and experimental results are presented as a guide to future application. Supplementary fueling is differentiated from pilot injection, and some of the limitations, potential problem areas and control design considerations are discussed. The use of propane (LPG) as a supplementary transportation fuel is compared with other candidate fuels, and opportunities for improving truck-engine performance, durability, economy, fuel tolerance, emissions and drive-ability are discussed.