Optimization and Modelling of EGR rate and MIS for POME fuelled CRDI diesel engine

Abstract

In the present research work an optimisation stuy of the Exhaust gas recirculation (EGR) rate for MIS adopted POME fueled CRDI Diesel Engine fitted with TRCC was carried out. The engine was operated with injection parameters such as 900 bar, 7 holes and 10° BTDC which have been optimized for better performance and lower emissions from our previous study. The experiments were carried out by employing an RSM-based D-optimal design, and the relationship between input and output was determined using an ANOVA. Using RSM-ANOVA, mathematical models were built for each result, and the predicted and actual outcomes were compared. With an R2 value greater than 99.34%, the prediction models were discovered to have a strong prediction efficiency. The desirability approach-based optimisation was used to determine the ideal engine operating parameters. EGR rate was varied from 0% to 20% and an MIS of 40 + 20+40 has been adopted for the engine. An EGR rate of 10% is optimized from the viewpoint of NOx reduction and penalty in power output which results in a decrease in brake thermal efficiency by 2.90%, peak pressure by 4.8%, heat release rate by 8.8% and oxides of nitrogen (NOx) by 1.35%. A drastic increase in emissions such as carbon monoxide by 5.8%, unburnt hydrocarbon by 13.3% and smoke by 20.6% was also observed. Both the ANN and RSM models correctly fit the experimental data, producing R2 values that ranged from 95.5% to 98.5%, respectively. The findings show that RSM and ANN are both highly accurate modelling approaches. Additionally, as compared to RSM, the ANN model's predictive accuracy was marginally better. This research could have a wide range of applications in CI engine-powered transportation systems.