Direct numerical simulation of a turbulent lean premixed CH4/H2-Air slot flame

Increasing the hydrogen content the expected value and the skewness factor of the curvature PDF move towards negative values. The effect of thermal diffusion in thinning the flame front is greater for positive curvatures and at the trailing edge of the flame. The addition of hydrogen reduces the displacement speed at negative curvatures in a range that depends on the local progress variable value, with a maximum variation of − between the two flames. However, on average, increasing the hydrogen content increases the displacement speed in a wide range of progress variable values, i.e., the Sd in flame B is, on average, higher than in flame A by ∼25% in 0.25 < c < 0.75. The database will also be helpful to validate sub-grid models for Large Eddy Simulation.