Surface Density Function Evolution in Spherically Expanding Flames in Globally Stoichiometric Droplet-laden Mixtures

Displacement speed statistics in an open turbulent jet spray flame

“…Significant insights into the behaviour of the combustion of turbulent droplet-laden mixtures through both experimental [5][6][7][8][9][10][11][12][13][14] and numerical [14][15][16][17][18][19][20][21][22][23][24][25][26][27] investigations have been obtained. Furthermore, recently several Direct Numerical Simulations (DNS) analyses [19][20][21][24][25][26][27] focussed on the flame propagation statistics in turbulent droplet-laden mixtures in canonical configurations.…”

“…Significant insights into the behaviour of the combustion of turbulent droplet-laden mixtures through both experimental [5][6][7][8][9][10][11][12][13][14] and numerical [14][15][16][17][18][19][20][21][22][23][24][25][26][27] investigations have been obtained. Furthermore, recently several Direct Numerical Simulations (DNS) analyses [19][20][21][24][25][26][27] focussed on the flame propagation statistics in turbulent droplet-laden mixtures in canonical configurations. In these analyses [19][20][21][24][25][26][27], the statistical behaviours of the displacement speed of the reaction progress variable 𝑐 have been analysed, providing important information with respect to modelling methodologies in turbulent spray flames.…”

“…Furthermore, recently several Direct Numerical Simulations (DNS) analyses [19][20][21][24][25][26][27] focussed on the flame propagation statistics in turbulent droplet-laden mixtures in canonical configurations. In these analyses [19][20][21][24][25][26][27], the statistical behaviours of the displacement speed of the reaction progress variable 𝑐 have been analysed, providing important information with respect to modelling methodologies in turbulent spray flames. These statistics of displacement speed are fundamentally important for flame surface area evolution [28] and both level-set [29], and Flame Surface Density (FSD) [28] based approaches of turbulent reaction rate closure.…”

“…These statistics of displacement speed are fundamentally important for flame surface area evolution [28] and both level-set [29], and Flame Surface Density (FSD) [28] based approaches of turbulent reaction rate closure. However, the effects of mean shear were absent in the configurations analysed in [19][20][21][24][25][26][27] and thus it is worthwhile to analyse the flame propagation in a configuration with mean shear, which is typical of laboratory and industrial scale burners. Several recent analyses concentrated on displacement speed statistics of turbulent premixed flames in a laboratory-scale burner [30][31][32] and canonical configurations [33] based on high-fidelity simulations but such an analysis is yet to be carried out for turbulent spray flames.…”

“…The current analysis builds upon the existing literature of flame propagation into droplet-laden mixtures [19][20][21][24][25][26][27] by considering an open turbulent jet spray flame [22,23], analysing the behaviour of the density-weighted displacement speed 𝑆 𝑑 * and its components at different axial locations of the spray flame. The main objectives of the current study are:…”