ABSTRACT
The paper consists of experimentation & simulation of dual fuel (Diesel-CNG) engine of off road vehicle. It is novelty to introduce first time in India. The tractor engine consists of 4 cylinder, 4 stroke, direct injection naturally aspirated engine. Existing tractor engine is converted into dual fuel mode and tests are conducted. Diesel engine was successfully converted to dual fuel mode and simulation in GT power was validated with experimental tests performed on test bed. Simulation in GT power i.e. engine modeling for diesel as well as dual fuel engine includes 1D thermodynamic analysis of combustion & performance parameters. The results were obtained by maintaining the performance of diesel engine by testing engine with Nα mode (N-Engine speed, α- Throttle). Six different cases were taken by varying speed of engine. Results show that the engine operation is more economical on the pure diesel mode at lower speed; however, at higher speed dual-fuel operation is better. BSFC is lower for dual fuel mode compared to diesel by 8%. Volumetric efficiency of dual fuel engine is lower as compared to diesel engine by 5%, PM concentration under dual fuel operation is lower compared to normal Diesel operation. CO and HC emissions levels are considerably higher compared to normal Diesel operation. Hence, CO and NOx are reduced with aftertreatment devices such as DOC and EGR respectively. Dual fuel engine effectively meets the emission norms and is compatible for off road vehicles.
