Effects of EGR, injection retardation and ethanol addition on combustion, performance and emissions of a DI diesel engine fueled with canola biodiesel/diesel fuel blend

Abstract

Biodiesel fuels have been used in diesel engines at different ratios without modifications in the engines. However, the biodiesel fuels generally generate higher NOx emissions than those of the diesel fuel and the related investigations on the higher NOx problem are still ongoing. In this study, three moderation techniques namely exhaust gas recirculation, injection retardation and ethanol addition were comparatively addressed for B10 biodiesel blend (10% canola biodiesel and 90% diesel fuel in vol.). The experimental results revealed that the exhaust gas recirculation of 5% is a suitable method in improving the combustion parameters of B10 biodiesel blend, while the retarded injection timing of 2 CA° is the most effective method regarding both the performance and emission parameters. No favorable effect of 2% ethanol addition to B10 biodiesel blend at retarded injection timing was observed on the performance, and coefficient of variation of indicated mean effective pressure was increased by over 10%. However, all methods examined in this study have effective potentials in the decrease of NOx emissions of the diesel engine running with the B10 biodiesel blend.