Evaluation of performance, emissions and combustion attributes of diesel engines powered by Palmyra biodiesel blends with distinct injection pressures and EGR rates

The present work explores the viability of Palmyra oil methyl ester (POME) as a renewable biodiesel. Initially, oil is extracted from the Palmyra fruit and the oil is transesterified to produce Palmyra oil methyl ester. Preliminary tests were conducted with blends of Palmyra oil methyl esters. From the test results, it was found that the POME20 blend performed better than other blends and was considered as an optimised blend. Secondly, analysis was carried out with POME20 on the CI engine at three injection pressures (210bar, 230bar and 250bar). POME20 at 230bar was shown to have improved thermal efficiency and reduced emissions of CO, HC and CO2 except NOX emissions. Finally, the tests were repeated for optimal conditions of 230bar injection pressure along with 6% and 12% EGR rates. The experimental results revealed that POME20 operated at 230bar 6% EGR rate observed a drastic reduction of NOX by 32.08% and 57.49% compared to diesel and POME20.