Comparison of three interacting V-Flames to a single bluff body flame at two reynolds numbers

The axial velocity profiles for three interacting bluff-body flames at Reynolds numbers of 4000 and 6000 are compared to a single-flame case at the same Reynolds numbers and equivalence ratio of ϕ=0.8. To facilitate a direct comparison between interacting and single-flame behaviors, an interacting flame case has been chosen to have a very similar time-averaged flow field as the single-flame configuration. While the inlet turbulence levels of the single-flame and interacting flame configurations are the same, the turbulence field development is different when multiple flames are present, leading to higher reactant Reynolds stresses along the (Formula presented.) contour in the cross-stream direction when there is flame interaction. The principal directions are calculated and show that the flame surface normals tend to align with most compressive principal strain. Flame surface density is quantified for both flame configurations and indicates there is more flame wrinkling when flame interaction is present. The higher cross-stream Reynolds stresses cause increased flame wrinkling which results in faster flame brush growth when there is flame interaction. Flames are found to anisotropically redistribute turbulent kinetic energy, preferentially enhancing cross-stream fluctuations in the products. These results demonstrate that the multiple bluff-body flame behavior cannot be considered a superposition of the dynamics of the single bluff-body flame.