The transportation sector’s growing focus on addressing environmental and
sustainable energy concerns has led to a pursuit of the decarbonization path. In
this context, hydrogen emerges as a promising zero-carbon fuel. The ability of
hydrogen fuel to provide reliable performance while reducing environmental
impact makes it crucial in the quest for net zero targets. This study compares
gasoline and hydrogen combustion in a single-cylinder boosted direct injection
(DI) spark ignition engine under various operating conditions. Initially, the
engine was run over a wide range of lambda values to determine the optimal
operating point for hydrogen and demonstrate lean hydrogen combustion’s benefits
over gasoline combustion.
Furthermore, a load sweep test was conducted at 2000 rpm, and the performance and
emission results were compared between gasoline and optimized hydrogen
combustion. An in-depth analysis was conducted by varying fuel injection time
and pressure. This enabled us to explore the effects of these variables on the
fuel’s performance and emissions, providing valuable insights for further
optimization.
The key findings of this study are significant. They note that hydrogen fuel
allows the engine to operate under lean conditions with stable combustion up to
3.8 lambda. Lean combustion produces higher engine thermal efficiency, low
cyclic variability, and near-zero NOx emissions. According to the
study, hydrogen combustion produces zero emissions of hydrocarbons (HC), carbon
monoxide (CO), and carbon dioxide (CO2) under a wide range of
operating conditions, making it a clean and environmentally friendly fuel
source. During low loading, exhaust hydrogen slip is less than 1000 ppm. This
slip drops below 500 ppm as the load increases. Finally, the study proved that
hydrogen is more stable than gasoline at a stoichiometric level. This suggests
that hydrogen could replace gasoline in some applications, which has major
implications for alternative energy.
