Article

Ammonia combustion analysis: powertrains, turbines & power generation

This week we explore four updates in ammonia combustion R&D:

1. A team from the University of Cambridge has shown merchant vessels are the strongest candidates for conversion to run on ammonia powertrains, with cargo capacity losses of 4-9% able to be feasibly offset by operators.

2. Researchers at the University of Minnesota have successfully tested a thermochemical recuperation (TCR) reactor to improve the efficiency of a dual-fuel, diesel-ammonia compression ignition engine by minimising ammonia slip.

3. A global team led by Cardiff University researchers has revealed some of the inner workings of ammonia combustion in gas turbine flames.

4. A global team has produced a cradle-to-gate environmental assessment for ammonia production and ammonia-based electricity generation, suggesting that renewable and nuclear ammonia have a significant role to play in decarbonising the power sector.

Article

Literature Review: Ammonia as a Fuel for Compression Ignition Engines

The diesel engine, also known as the compression ignition (CI) engine, has been a workhorse of the modern energy economy for more than a hundred years. Its role in the coming sustainable energy economy will be determined by its ability to co-evolve with climate-friendly fuels. Two researchers from the National Institute of Advanced Industrial Science and Technology in Japan have now examined the fit between ammonia and the CI engine. Pavlos Dimitriou and Rahat Javaid arrive at a two-part conclusion in their paper, “A review of ammonia as a compression ignition engine fuel,” published in January in the International Journal of Hydrogen Energy. Part one is good news: “Ammonia as a compression ignition fuel can be currently seen as a feasible solution.” Part two is a dose of qualifying reality: to manage emissions of N2O, NOx, and unburnt NH3, “aftertreatment systems are mandatory for the adaptation of this technology,” which means that ammonia-fueled CI engines are likely to be feasible “only for marine, power generation and possibly heavy-duty applications where no significant space constraints exist.”

Paper

Recent progress on the Ammonia-Gasoline and the Ammonia-Diesel Dual Fueled Internal Combustion Engines in Korea

Both a spark ignition engine and a compression ignition engine are considered to use ammonia as primary fuel in this study. First, in a spark ignition engine, an ammonia-gasoline dual fuel system was developed and both ammonia and gasoline are injected separately into the intake manifold in liquid phase. As ammonia burns 1/6 time slower than gasoline, the spark timing is needed to be advanced near 40 degree before top dead center. The test engine showed quite high variation in the power output with ammonia supply more than 70% of the total heat value. As a result, 70% of gasoline…