The ACTIVATE team published their results on ammonia/diesel dual-fuel engine in the Journal of the Energy Institute (IF=6.47) on 12 December 2022. Free open access here.
Ammonia is currently receiving more interest as a carbon-free alternative fuel for internal combustion engines (ICE). A promising energy carrier, easy to store and transport, being liquid, and non-carbon-based emissions which make ammonia a green fuel to decarbonize ICE and to reduce greenhouse gas (GHG) emissions. This paper aims to illustrate the impacts of replacing diesel fuel with ammonia in an ammonia/diesel dual fuel engine. Hence, the effects of various ammonia diesel ratios on emissions and engine performance were experimentally investigated. In addition, a developed 1D model is used to analyze the combustion characteristics of ammonia and diesel. Results show 84.2% of input energy can be provided by ammonia meanwhile indicated thermal efficiency (ITE) is increased by increasing the diesel substitution. Moreover, increasing the ammonia energy share (AES) changed the combustion mode from diffusion combustion in pure diesel operation to premixed combustion in dual fuel mode. Therefore, combustion duration and combustion phasing decreased by 6.8CAD and 32CAD, respectively. Although ammonia significantly reduced CO2, CO, and particulate matter (PM) emissions, it also increased NOX emissions and unburned ammonia (14800 ppm). Furthermore, diesel must be replaced with more than 35.9% ammonia to decrease GHG emissions, since ammonia combustion produces N2O (90 ppm) that offsets the reduction of CO2.
Keywords: Ammonia, Dual fuel, Diesel engine, Emissions, GHG emissions
- The effects of various ammonia-diesel ratios were investigated experimentally.
- 84.2% of the input energy was provided by ammonia.
- Ammonia reduced the combustion phasing and combustion duration periods.
- The ammonia-fueled CI engine significantly reduced GWP emissions by 3 times over 100 years scale.