A Direct Numerical Simulation Assessment of Turbulent Burning Velocity Parametrizations for Non-Unity Lewis Numbers

The predictions of turbulent burning velocity parameterizations for non-unity Lewis number flames have been assessed based on a single-step chemistry Direct Numerical Simulation (DNS) database premixed Bunsen different values characteristic numbers ranging from 0.34 to 1.2. It has found that the definition is strongly dependent choice projected flame brush area in burner configuration. highest normalized are obtained when evaluated using isosurface Reynolds averaged reaction progress variable 0.1 out options, namely Favre and isosurfaces 0.5 integral gradient variable. Because axisymmetric nature mean brush, decrease as burned gas side approached, due an increase with increasing radius. Most models provide comparable, reasonably accurate unity case 0.1. However, most these underpredict smaller than unity. A scaling relation utilized extend numbers. These revised shown be more successful original model expressions. modified expressions also exhibit small L2-norm relative error respect experimental data literature numbers, higher turbulence intensity thermodynamic pressure levels.