Effect of exhaust gas recirculation on performance and emission characteristics of a diesel engine fuelled with tamarind biodiesel

The present research work focuses on the influence of exhaust gas recirculation (EGR) on the characteristics of the diesel engine operated with 20% tamarind seed methyl ester (TSME 20) as the renewable fuel. The use of TSME 20 as biodiesel results in closer performance characteristics with diesel fuel. However, TSME 20 biodiesel blend generated higher oxides of nitrogen (NOx) emissions at all operating conditions. Firstly, tests are performed using diesel and TSME 20 biodiesel blend at constant speed under different loads. Thereafter, experiments are conducted on TSME 20 with EGR rates at different concentrations. The test results revealed that with TSME 20 with 20% EGR rate, NOx emissions are reduced by 45.67% and 52.69% when compared to diesel and TSME 20. However, there is a slight reduction in brake thermal efficiency. Hence, the use of 20% EGR rate to TSME 20 is an optimum approach for better control of NOx emissions.