Effects of radiation heat loss on laminar premixed ammonia/air flames

Hisashi Nakamura, Mitsumasa Shindo

Research output: Contribution to journalArticlepeer-review

62 Citations (Scopus)


Ammonia (NH 3 ) direct combustion is attracting attention for energy utilization without CO 2 emissions, but fundamental knowledge related to ammonia combustion is still insufficient. This study was designed to examine effects of radiation heat loss on laminar ammonia/air premixed flames because of their very low flame speeds. After numerical simulations for 1-D planar flames with and without radiation heat loss modeled by the optically thin model were conducted, effects of radiation heat loss on flame speeds, flame structure and emissions were investigated. Simulations were also conducted for methane/air mixtures as a reference. Effects of radiation heat loss on flame speeds were strong only near the flammability limits for methane, but were strong over widely diverse equivalence ratios for ammonia. The lower radiative flame temperature suppressed the thermal decomposition of unburned ammonia to hydrogen (H 2 ) at rich conditions. The equivalence ratio for a low emission window of ammonia and nitric oxide (NO) in the radiative condition shifted to a lower value than that in the adiabatic condition.

Original languageEnglish
Pages (from-to)1741-1748
Number of pages8
JournalProceedings of the Combustion Institute
Issue number2
Publication statusPublished - 2019


  • High-resolution transmission molecular absorption database (HITRAN)
  • Mechanism validation
  • Nitrogen dioxide (NO )
  • Nitrogen oxides (NOx)
  • Nitrous oxide (N O)


Dive into the research topics of 'Effects of radiation heat loss on laminar premixed ammonia/air flames'. Together they form a unique fingerprint.

Cite this