Effect of the Obstacle Position on Explosion Characteristics of Inhomogeneous Hydrogen-Air Mixtures
B.-Y. Qi, Z.-H. Sheng, G.-G. Yang, S.-A. Li, Q.-W. Shen, H. Sun,
H.-D. Jia, Z.-X. An
Marine Engineering College, Dalian Maritime University, Dalian, China
Keywords: obstacle position, concentration gradient, hydrogen explosion, flame structure, numerical simulation
Abstract
The effect of different obstacle positions on the explosion flame dynamics of hydrogen-air mixtures with concentration gradients is investigated by numerical simulations. The numerical simulations predict explosion characteristic parameters matching correctly with the experimental results. The calculation results show that the influence of the obstacle position on the explosion flame of an inhomogeneous mixture is more significant compared to that of a homogeneous mixture. The analysis of the flame morphology and flow field reveals that, as the obstacle position increases, the premixed flame undergoes more complex deformation after passing through the obstacle and generates eddies near the obstacle under the action of vortices. By comparing the flame front position and peak overpressure after the explosion, it is found that, as the obstacle position increases, the concentration gradient has a stronger inhibitory effect on flame propagation. The influence of the concentration gradient on the peak overpressure is more pronounced when the obstacle is 200 mm from the ignition point. This research can provide theoretical guidance for industrial explosion protection and safety management.
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