Thermodynamic performance of a compression-ignition engine fueled with a diesel–fuel oil blend with nanographene addition and oxyhydrogen enrichment: Energy and exergy analysis

This study examines how adding nanographene and enriching with oxyhydrogen (HHO) affect the energy and exergy performance of diesel–fuel oil blends in a compression-ignition engine. Nanographene was introduced to the DF40 blend (60% diesel, 40% fuel oil by volume) at 50 and 100 ppm, and HHO was supplied to the intake manifold at 5 and 10 L min 1 . Engine tests were performed at 3000 rpm with loads ranging from 3.2 to 12.8 Nm. The combined use of nanographene and HHO enhanced thermodynamic performance. At a load of 7.9 Nm, thermal and exergy efficiencies increased from 20.53% and 19.25% for DF40 to 25.80% and 23.72% for DF40N100H10, respectively. Maximum thermal and exergy efficiencies reached 31.66% and 29.11% at 12.8 Nm, while exergy destruction decreased by up to 23.1%. These results demonstrate the potential of nanographene addition and HHO enrichment to improve the thermodynamic performance of diesel–fuel oil blends under the tested conditions.