Experimental study of combustion process of NH3 stratified spray using imaging methods for NH3 fueled large two-stroke marine engine

Mini Review of Ammonia for Power and Propulsion: Advances and Perspectives

“…However, to achieve part load operation in addition to full load operation, the advanced injection of NH 3 was found to be necessary. In two sister studies, Ichikawa et al 114,115 evaluated experimentally the potential of the three-layer stratified injection concept, where liquid NH 3 is sprayed in between injections of supporting n-hexadecane. Although experiments were conducted in a constant volume combustion chamber, its large dimensions (350 mm height and 150 mm diameter) and its operating conditions (50 bar and 783 K) emulate a cylinder from a two-stroke marine engine.…”

“…Recent publications focusing on NH 3 marine engines are mostly considering dual-fuel strategies, namely NH 3 -diesel, ,,, NH 3 -H 2 , NH 3 -natural gas, or NH 3 - n -hexadecane , ( n -hexadecane was used instead of diesel to make the first demonstration of a new NH 3 injection concept easier at first thanks to its larger cetane number). Given the difficulty of operating actual marine engines in research laboratories, recent studies dealing with marine engines are purely numerical, ,,,, with perhaps the exception of Oh et al, who conducted measurements in a 222 kW, 11-l, 6-cylinder engine whose total displacement is comparable to that of a small marine engine.…”

“…Temporal sequence of direct broadband flame images recorded at high-speed for the three-layer stratified injection concept. Adapted from Ichikawa et al Modified with permission from ref . Copyright 2023 Elsevier.…”