The impact of ammonia and hydrogen additives on the combustion characteristics, performance, stability and emissions of an industrial DF diesel engine

Abstract

Listen

Translate article

Both hydrogen and ammonia are potential fuels that can significantly replace fossil fuels in the automotive and energy sectors. In compression ignition engines, they can be effectively and efficiently co-combusted with diesel fuel. This study presents experimental comparative research on the impact of alternative fuels, namely ammonia and hydrogen, on the performance, stability, and emissions of an industrial dual-fuel compression ignition engine. The research was conducted on an engine operating under constant load (0.7 MPa) and constant speed (1500 rpm), comparing scenarios of diesel-only operation and alternative fuel energy shares of 8 %, 12 %, 24 %, and 32 %. For both ammonia/diesel and hydrogen/diesel engines, combustion characteristics, performance, and emissions were determined and analyzed. Additionally, an evaluation of the dual-fuel engine’s operational stability was conducted. For the compression ignition engine co-combusting ammonia with diesel, the most favorable solution was using a 32 % energy share of NH3. In this configuration, the engine achieved nearly the highest efficiency (38 %), the most stable operation, and the lowest emissions of harmful and toxic exhaust components (NO = 2.23 g/kWh, HC = 0.2 g/kWh, CO = 24.9 g/kWh, CO2 = 512 g/kWh, Soot = 0.51 g/kWh). For the engine co-combusting hydrogen with diesel, the optimal energy share of H2 was 24 %. In this configuration, the engine achieved the highest efficiency (39.8 %), almost the most stable operation, and the lowest emissions of HC = 0.22 g/kWh, CO = 15.8 g/kWh, CO2 = 434.7 g/kWh and Soot = 0.52 g/kWh. Unfortunately, a significant drawback of using H2 in a compression ignition engine is the substantial increase in NO emissions.