[RWaluyo]

Dear all,
I am doing simulation for NH3/H2/air combustion using OpenFOAM-8 (Foundation ver.) with reactingFoam solver. There is no run time error detected, however I failed to achieve sustainable flame.

The boundary condition is based on successful experiment [1] so I don't think that specifying fuel/oxidizer composition beyond NH3/H2 flammability range is causing this ignition failure.

I also conducted similar simulation by adding NH3 on steady H2 combustion with same chemical mechanism proposed by Okafor at al. [2] The generated flame is sustainable which indicated by steady consumption of NH3. From this observation, I deduce that the problem lies on numerical side specifically mesh.

I need to get the flame ignited in my simulation so I could validate the results with experimental data. Any help would be greatly appreciated.
Attached with this message are:
1) Animation of failed ignition simulation
2) Animation of sustainable flame (different mesh)
3) Case that could be used to reproduce the failed ignition. Already tested for both series and parallel run.

NH3-TNF.zip

Failed_H2-NH3-O2.zip

sus-flame_H2-NH3-O2.zip

Regards,

Waluyo

Refereces:
[1] Tang, H., Yang, C., Wang, G., Krishna, Y., Guiberti, T. F., Roberts, W. L., & Magnotti, G. (2022). Scalar structure in turbulent non-premixed NH3/H2/N2 jet flames at elevated pressure using Raman spectroscopy. Combustion and Flame, 244.
[2] Okafor, E. C., Naito, Y., Colson, S., Ichikawa, A., Kudo, T., Hayakawa, A., & Kobayashi, H. (2018). Experimental and numerical study of the laminar burning velocity of CH4–NH3–air premixed flames. Combustion and Flame, 187, 185–198. https://doi.org/10.1016/j.combustflame.2017.09.002