Numerical Investigation of Lean Neat Ammonia Combustion in a Heavy-Duty Diesel Engine Converted to Spark Ignition West Virginia University

Format:

Book

Conference/Event

Author/Creator:

Saenz Prado, Stefany, author.

Contributor:

Akkerman, Vyacheslav

Alvarez, Luis F.

Dumitrescu, Cosmin E.

Trujillo Grisales, Juan M.

Conference Name:

17th International Conference on Engines and Vehicles (2025-09-14 : Capri, Italy)

Language:

English

Physical Description:

1 online resource cm

Place of Publication:

Warrendale, PA SAE International 2025

Summary:

Ammonia (NH3) use as fuel poses technical challenges such as increased nitrogen-based and unburned NH3 emissions. This study used a 0D model coupled with detailed NH3 kinetics to evaluate the effect of equivalence ratio () from 0.7 to 1.0 in a heavy-duty compression ignition engine converted to spark ignition operation. The goal was to evaluate how affected NOx and N2O formation and/or destruction at constant fuel energy per cycle, engine speed, and CA50. Simulated NOx emissions (id est, NO + NO2) followed a trend similar to the one typically observed for hydrocarbon fuels in a SI engine, but that was different from the experiment. In addition, it underpredicted NOx emissions for = 0.7 by 79% and overpredicted NOx emissions for = 1 by 576%. The simulation showed that thermal NO production was more than 80% from the total NO production, but the effect of on this percentage was negligible. Then, predicted N2O emissions had an opposite trend and were three orders of magnitude lower than the experiment. Under the assumption that post-combustion phenomena can explain these differences, an additional reactor simulating of the chemistry inside the unburned mixture exiting crevices post combustion at = 0.9 predicted N2O production similar to experimental data and an additional 20 ppm of NO. A third reactor simulating the exhaust blowdown predicted substantial DeNOx reactions (up to 3000 ppm decrease in NOx), and a large N2O production above experimental values. Therefore, the significant DeNOx and N2O formation reactions could explain the differences between the 0-D engine simulation and experiments even when accounting for the real mixture inhomogeneities, which emphasizes the importance of capturing both in-cylinder and post-EVO conditions when modeling NOx and N2O emissions in an IC engine

Notes:

Vendor supplied data

Publisher Number:

2025-24-0032

Access Restriction:

Restricted for use by site license