(Color online) Schematic of the computational geometry.
(Color online) Instantaneous snapshots of the velocity fluctuations in (a) streamwise and (b) wall-normal directions at a fixed xz-plane; 8 < y + < 10. The colorbar at the top of each panel shows the positive and negative fluctuations.
(Color online) Snapshots of oxidizer concentration (top) and fuel concentration (bottom).
(Color online) Snapshots of the reaction rate in (a) xy-plane and (b) xz-plane at a fixed distance from the wall, y/h = 1/2, both show the same time instant. The lighter color indicates to the higher reaction rate.
(Color online) Stoichiometric mixture surface.
(Color online) Comparison of reacting jet (solid) to non-reacting wall-jet by Ahlman et al. (Ref. 23) (dashed), at downstream position x/h = 25. (a) Inlet normalized mean streamwise velocity and (b) mean streamwise velocity in inner units. Here y + is yu τ/ν. (c) Downstream development of friction velocity at the wall and the jet half-height and (d) friction Reynolds number.
Comparison of reacting jet (solid) to non-reacting wall-jet by Ahlman et al. (Ref. 23) (dashed), at a downstream position x/h = 25. (a) Streamwise fluctuation intensity in outer scaling, (b) Reynolds shear stress normalized by , (c) cross stream profiles of the conserved scalar fluctuation intensity, and (d) wall-normal flux of the conserved scalar.
(Color) Statistics of oxidizer (blue), fuel (red), and passive (black) scalars at several downstream positions. Solid: x/h = 21, dashed: x/h = 23, dash-dotted: x/h = 25, dotted: x/h = 27 (a) reactants mass flux, (b) cross-stream profiles of the reacting scalars, (c) fluctuation intensity of the passive and reacting scalars, and (d) wall-normal fluxes of passive and reacting scalars. Subscript m refers to the local maximum value of the corresponding variable.
Inlet normalized (a) reaction rate and (b) the expected reaction rate corresponding to the product of the mean concentrations at different downstream positions. Line styles are the same as in Figure 8.
Ratio of the maximum reaction rate, peak value of Figure 9(a), to the maximum of the expected corresponding value computed from the mean concentrations, peak value of Figure 9(b).
(Color online) Probability density functions of different species at x/h = 25 in several wall-normal locations. Minimum and maximum concentrations in each plot match the borders of the plot and zero on x-axis points to the mean concentration.
Distributions of third-order moments (skewness) and the fourth-order moments (flatness) of streamwise velocity u, wall-normal velocity v, spanwise velocity w, passive scalar concentration θ, and the fuel species concentration θ f , in a reacting turbulent wall-jet. Solid: x/h = 15, dashed: x/h = 20, and dash-dotted: x/h = 25.
The skewness factors for (a) streamwise and (b) wall-normal velocity fluctuations at downstream postion x/h = 8.7, solid line: present DNS data, star symbols: experimental data of Ref. 41.
(Color online) Turbulence intensity, skewness, and flatness factors of the streamwise velocity at downstream position x/h = 25. The red lines show the positions of the skewness factor zeros.
Turbulent kinetic energy viscous dissipation rates using (a) inner and (b) outer scaling at different downstream positions; Solid line: x/h = 21 and dashed line: x/h = 25.
Passive (a) and reacting (b) scalar dissipations using outer scaling at different downstream positions; Solid line: x/h = 21 and dashed line: x/h = 25.
Simulation cases, L i and N i are the domain size and grid points in the i-direction.
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