Effect of Diesel-Ignited Ammonia/Hydrogen mixture fuel combustion on engine combustion and emission performance

Abstract

To reach zero carbon emissions and meet carbon neutrality targets, ammonia is one of the most promising zero-carbon fuels. However, ammonia escapes significantly when too much ammonia is blended. Therefore, a certain percentage of hydrogen is blended with the ammonia, which can promote in-cylinder combustion reactions. This paper aims to study the effect of varying ammonia blending hydrogen ratio on in-cylinder explosion pressure, temperature, power, fuel consumption rate, CA50, ammonia escape ratio, hydrogen escape ratio, NOx, CO2 and soot emissions under two ignition modes when the diesel engine speed of 1800 r/min at rated operating conditions in a high-pressure common rail diesel engine, and set nine groups of hydrogen blending ratios from 10% to 90% for diesel ignition. The results show that: when the hydrogen blending ratio is 30% compared to 0, the in-cylinder explosion pressure increases by 10.7%, the power increases by 1.8%, the fuel consumption rate decreases by 0.3%, the ammonia escape ratio decreases by 99.1%, the NOx emissions increase by 58.8%, the CO2 increases by zero, the soot and HC emissions improvements, and the overall performance of the diesel engine is improved after hydrogen blending combustion. To achieve the net-zero carbon emission goal of carbon neutralization, a small amount of diesel ignition direct injection ammonia blended with 30% hydrogen is the better solution.