Research on Pressure Oscillation Characteristics in Constant Volume Bomb

In this paper, the pressure oscillation characteristics of n-heptane and isooctane at different mixing ratios are studied on a constant volume combustion bomb, and the relationship between the sound pressure signal and the brightness of the flame picture during the combustion process and the pressure oscillation characteristics are analyzed. Studies have shown that with the increase of the mixing ratio of n-heptane, the intensity of pressure oscillation gradually increases; under the same mixing ratio, the intensity of pressure oscillation first increases and then decreases with the increase of the equivalent ratio. In the experiment, the change trend of sound pressure and flame brightness is the same as the pressure. Finally, three inert gases of Ar/He/CO₂ were used to replace N₂ in experiments, which proved that the pressure oscillation in the container was caused by flame self-acceleration.