Data for publication: Hydrogen Jet Flame Control by Global Mode

Research data related to the publication "Hydrogen Jet Flame Control by Global Mode". In this study, we employ the potential of the global instability phenomenon to qualitatively alter the dynamics of a turbulent flame. We adopt the large eddy simulation method and an in-house numerical code. For the combustion process we do not include explicit sub-filter modeling. The accuracy of this ‘no combustion model’ approach is verified by comparison against the Eulerian Stochastic Fields method. We include several test cases representing different flow regimes, including convective and absolutely unstable conditions. The focus is on a counter-current configuration, which includes a central jet nozzle supplying hydrogen fuel surrounded by a somewhat larger co-axial nozzle sucking fluid from the surroundings of the central nozzle. The suction generates a counterflow where global instability is found to be triggered if sufficiently strong suction is applied. The critical suction value IGI is larger if the level of the inlet turbulence intensity Ti is increased. Depending on the suction strength, the flame quickly stabilizes, either as being attached to the nozzle or as a lifted flame hovering at a height of a few fuel nozzle diameters. Additionally, it is shown that increasing Ti can assist an initially lifted flame to attach to the nozzle. Flame lifting is the result of self-induced strong toroidal vortices that lead to leaner combustion conditions of the mixture upstream of the flame base. The toroidal vortices prevent upstream flame propagation and lead to a very intense mixing process that gives rise to the lifted reaction zone. This ensures almost complete fuel combustion at a short distance from the inlet.

The research was supported by the National Science Center in Poland (Grant No 2020/39/B/ST8/02802) and the National Agency for Academic Exchange (NAWA) within the International Academic Partnerships Programme (ANIMATE project No. PPI/APM/2019/1/00062).

The readme file contains sorted filenames linked to the figures from the article.

For details on file formats please refer to the readme file and documentation: https://www.tecplot.com/2016/09/16/tecplot-data-file-types-dat-plt-szplt/