Optimization of Multiple Injection Strategies to Improve BSFC Performance of a Common Rail Direct Injection Diesel Engine

Present stringent emissions norms; global fossil fuel energy scenario and competitive automotive market has driven many researches on diesel engine combustion in both academic and industry level. This work is an effort to improve the fuel economy without compromising emissions level of typical six cylinders inline CRDI diesel engine using optimized multiple injection strategy. There was some unusual nature of BSFC (Brake specific fuel consumption) observed on such typical engine. Also, Torque curve was not up to the mark for better drivability. This engine is equipped with most familiar in cylinder NO_x reduction device namely EGR and multiple injections. There were few experiments conducted on same engine to optimize the BSFC using different multi injection strategies in line to marginal change of injection timing with respect to crank angle. Total exercise was done following partial Design of Experiments (DOE). EGR % has kept unaltered. The effects of multiple injection strategies (Pilot-main- After [PMA] and Pilot 2- Pilot - main- After [EPMA]) have been analyzed through this work. The secondary objective of this work is to understand the relationship between injection strategies, BSFC, other performances (torque, Power) and emissions. This study shows significant improvement on BSFC and Torque without affecting other performance parameters and Emissions.