V. Pirouzpanah - Mechanical Engineering, University of Tabriz
Y. Asadi - Mechanical Engineering, University of Tabriz

In order to use gaseous fuels in Diesel Engines, Dual-Fuel Diesel Engine (D. F. D. E) the pilot injection approach is chosen. To predict its performance, an engine cycle model, based on limited-pressure Diesel cycle, is constructed. The model predicts D. F. D. E performance with LPG, and CNG gases. Comparing with pure Diesel engine, by increasing gas proportion in dual-fuel, indicated power and hence indicated mean effective pressure are increased. Effect on thermal efficiency is not so appreciable, but indicated specific fuel consumption is quits considerable, and hence fuel economy of D. F. D. E is superior.