Ammonia Combustion with Ignition Improvement Measures in a High-Speed Marine Application

SAE technical papers on CD-ROM/SAE technical paper series, vol. 1

Abstract

Ammonia (NH3) has gained significant attention as a zero-carbon fuel which is capable of supporting global decarbonization goals, especially in the maritime transportation and power generation sectors. Its hydrogen density, storage feasibility, established production methods, and transportation infrastructure are key benefits which contribute to its potential both as a hydrogen carrier and as a direct fuel. The study investigates the combustion characteristics and emission profiles of ammonia on a spark ignited 2.13L single cylinder engine with the goal of evaluating ammonia as a single fuel. This displacement is representative of the typical cylinder displacement of small to mid-size engines for marine applications on sportfishing boats and as auxiliary power units. Challenges to consider for ammonia combustion are its high ignition energy requirement and low laminar flame velocity. Several methods were employed to compensate for these properties such as increasing compression ratio, the use of a passive pre-chamber spark plugs, and the use of hydrogen in a dual fuel set-up. The experimental results demonstrate stable combustion of 100 % ammonia under homogenous stoichiometric condition. NOX emissions reach typical levels of SI engines, around 8 – 12 g/kWh. Meanwhile, a certain level of NH3 emissions are unavoidable and require a customized exhaust aftertreatment. Up to 45 % indicated efficiency have been reached. The evaluation of the combustion enhancement techniques shows clearly that the higher CR, the use of a pre-chamber spark plug as well as the addition of a small hydrogen share all significantly reduce the burn delay and speed up the combustion considerably. Moreover, the NH3/NOX ratio in the exhaust gas is directly affected by these techniques which have relevance for the operation of an SCR aftertreatment system.

Authors 9

1. Zhen Li Aachen

   RWTH Aachen University

   Affiliation as printed

   TME RWTH Aachen University

2. Moritz Lückerath Aachen

   RWTH Aachen University

   Affiliation as printed

   TME RWTH Aachen University

3. Stefan Pischinger Aachen

   RWTH Aachen University

   Affiliation as printed

   TME RWTH Aachen University

4. Aleksandar Boberic Aachen FEV Europe GmbH

   FEV (Germany)

   Affiliation as printed

   FEV Europe GmbH

5. Bjoern Franzke Aachen FEV Europe GmbH

   FEV (Germany)

   Affiliation as printed

   FEV Europe GmbH

6. Avnish Dhongde Aachen FEV Europe GmbH

   FEV (Germany)

   Affiliation as printed

   FEV Europe GmbH

7. Bartosch Jagodzinski Aachen FEV Europe GmbH

   FEV (Germany)

   Affiliation as printed

   FEV Europe GmbH

8. John Burrows
   Affiliation as printed

   Champion Ignition

9. Metin Korkmaz
   Affiliation as printed

   Champion Ignition