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Experimental and numerical study on flame propagation and structure behaviors of methane-air premixed combustion in tube

The high speed Schlieren photography system and pressure sensors were used to investigate the flame propagation process of methane-air mixture in a small horizontal tube. The flame structure,propagation velocity and mixture pressure were obtained from the experiment. The results show that flame structure changes greatly in the flame propagation process,suddenly changing from a spherical laminar flame pointing forward to a V shape turbulent flame forming a cusp toward the burned gas. In this process,the velocity decreases but the pressure increases continuously. With the k-e turbulent combustion model,unsteady premixed methane flame in a 2D matrix burner was numerically simulated. The characteristics of flame propagation and flame structure variation qualitatively agree with the experimental data very well.