Performance Assessment of Petrol Engines with Hydrogen as an Alternative Fuel

Abstract

This research focused on reducing emissions from petrol engines to mitigate greenhouse gases. Experiments aimed to decrease pollutants from petrol engines and enhance efficiency at full load using hydrogen as a secondary fuel, injecting it for 2 milliseconds and 2.5 milliseconds. The study comprised two phases: one using petrol alone at all loads, and the other combining petrol with hydrogen injections at 216 gm/hour and 270 gm/hour. Performance, pollutants, brake, and mechanical efficiencies were compared between phases. Efficiency gradually improved with load for the 2ms injection. Efficiency improved in all timing cases with hydrogen compared to running on petrol alone. The highest efficiencies occurred with 2.5ms hydrogen injection, reducing pollutants at full load, making it the optimal interval. Injecting hydrogen in petrol engines improves efficiency by reducing emissions. Injecting hydrogen at 270 gm/hour at full load increased brake and indicated thermal efficiency by 9%, with no change in mechanical efficiency compared to pure petrol, which was slightly higher. Emissions of NO, CO2, and HC were reduced by 16.5%, 15%, and 17.2% respectively. Oxygen percentage by volume increased by 10.43%, supporting complete combustion.