Enhancement of biofuel engine characteristics through cyclic variation and multi-variate effect of split injection parameters

Abstract

With an aim of improving the biofuel combustion stability, the influence of using biofuels on the cyclic variation and the multi-variate effect of split injection parameters on CI engine is much significant to explore. For the orange peel oil blended diesel fuel, the complete research is preceded into three works. First, as a new approach, based on the cyclic variation the sample size, blend limit and influential injector parameters are identified. Second, investigation towards influential and factors interaction effect behaviour on response trend with an intention to extract the ample information's for the optimization. Third, based on the multi-variate engine operating factors response behaviour the optimum split injection control points are recognized. From the cyclic variation results, a 200 cycle sample size is sufficient for the data acquisition and the orange peel oil of 20% is the maximum limit point of proportion with diesel. The interactive factors effect study reveals the actual phenomenon of the engine responses significantly dependent on multifactor resulting in complex trade-off response trend. The employed desirability approach for performance and emission optimization suggested a trend of increased injection pressure from 500 to 700 bar, decreases the pilot mass of 28% to 20%, increased dwell time of 120 to 160 and advanced the pilot timing of 270 and 290 as the engine operating load increases from 20% to 80% of maximum torque. In comparison to un-optimized split injection control parameters, the BTE and BSFC of OPO20 improve to the maximum percentage of 8.11% and 7.01% at 60% engine load. While for emissions, HC and smoke are reduced with slight penalisation in NOx emissions. The 0.60% of NOx emission is increased with effective reduction of smoke up to 11.73%. This work experimentally delivers, a substantial enhancement in optimum trade-off performance and emission behaviour through cyclic variation and multi-variate effect of split injection parameters.