@misc{9236272,
  abstract     = {{The maritime sector needs to reduce greenhouse gas emissions and improve the sustain
ability of energy systems. Ammonia has attracted increasing attention as a potential
carbon-free marine fuel. However, ammonia has low reactivity, a high ignition energy
requirement, and a low flame propagation speed, which make stable combustion difficult.
Diesel-ignited ammonia combustion is therefore a promising method for improving
ammonia combustion performance.
This work is based on previous experimental studies conducted in a constant-volume
combustion chamber under high-pressure and high-temperature conditions, as well
as on a lab-scale, water-cooled two-stroke engine at Dalian University of Technology.
In the engine experiments, liquid ammonia and diesel were directly injected into the
cylinder through two opposing injectors. This provided relevant conditions for studying
diesel–ammonia dual-fuel combustion.
In this thesis, numerical simulations were carried out using OpenFOAM. The aim was to
investigate how injection angle and injector position affect flame development, ignition,
combustion intensity, and pollutant formation. Three different injection configurations
were compared under similar operating conditions.
The results show that the injection strategy has a significant influence on the combustion
process. Case 1 showed the most stable late-stage combustion. Case 2 produced the
highest heat release rate and the strongest localized combustion intensity. Case 3 showed
earlier ignition but weaker stability during the later combustion stage. Differences in
the distributions of NO and N2O also indicate that the interaction between the diesel
and ammonia jets affects the formation of nitrogen-containing pollutants.
To reduce computational cost, Chemistry Coordinate Mapping (CCM) and Error
Controlled Chemistry Coordinate Mapping (EC-CCM) were used. Both methods
reduced the computational time. EC-CCM provided the best balance between accuracy
and efficiency. Compared with the standard chemistry solver, EC-CCM achieved an
acceleration of approximately 3.67×, while maintaining good agreement in pressure,
temperature, and OH results.
This study provides numerical insight into diesel–ammonia dual-fuel combustion under
high-pressure conditions and shows that EC-CCM is a promising method for accelerating
detailed CFD simulations of combustion.}},
  author       = {{Liu, Yulong}},
  issn         = {{0282-1990}},
  language     = {{eng}},
  note         = {{Student Paper}},
  series       = {{Student paper}},
  title        = {{Evaluation of EC-CCM for numerical simulation of diesel-ignited ammonia combustion}},
  year         = {{2026}},
}