Large eddy simulations of multiple transcritical coaxial flames submitted to a high-frequency transverse acoustic modulation

Dynamics of a transcritical coaxial flame under a high-frequency transverse acoustic forcing: Influence of the modulation frequency on the flame response

“…When the modulation frequency is close to the natural frequency of the oxygen jet, the liquid core is displaced to a larger extent and the previous process is enhanced. (2) As shown in [69], these phenomena explain the difference in the heat release rate patterns observed in [40,69] during hot fire experiments with and without transverse acoustic forcing. Without modulation, the flame is homogeneously distributed around the liquid core, which is consequently not visible.…”

“…The spray distribution, which is clearly visible in [35], may well be at the origin of the double layer thick flame observed in [40,69].…”

“…The code has been extensively validated under transcritical conditions by simulating cold-flow and reacting cases with and without acoustic modulations and comparing results with available experimental data [64,65,67,69,76].…”

“…In order to capture the mechanisms induced by the acoustic modulation, phase-averaged data are considered. According to the experimental observations made in [40,69], the flame features a transverse motion which follows the external forcing. This behavior is retrieved in the simulations.…”

“…Efforts to model and simulate real-gas effects [47][48][49][50][51][52][53][54][55][56][57] in an unsteady transcritical combustion have allowed to examine flame structures and dynamics by making use of large eddy simulations (LES). LES of transcritical coaxial jets and flames [58][59][60][61][62][63][64][65] show that it is possible to obtain reasonable predictions of transcritical flames and that such simulations could be used to explore transcritical jets and flames behavior under acoustic forcing as demonstrated in [66][67][68][69].…”