Laminar burning velocity for Ch₄/air premixed flames at high pressure and high temperature for various equivalence ratios

Measurements of laminar burning velocities for CH₄/air/He premixed flames were performed in the pressure range of 0.1 to 1.0 MPa and in the temperature range of 298 to 600 K for various equivalence ratios of 0.8 to 1.2. Measurements were conducted by a technique which simultaneously measures the instantaneous local burning velocity using particle tracking velocimetry (PTV) and planar laser induced fluorescence for the OH radical (OH-PLIF). This technique provides information on the distribution of local burning velocities and Karlovitz numbers. Laminar burning velocities were determined using averaged values of local burning velocities in the region where Karlovitz numbers were sufficiently small. Numerical simulations were also conducted using detailed chemical reaction mechanisms, and results were compared with experimental data in order to investigate the feasibility of the reaction mechanisms at high pressure and high temperature.