Exploration of critical hydrogen-mixing ratio of quenching methane/hydrogen mixture deflagration under effect of porous materials in barrier tube

Abstract

To improve the safety of the methane/hydrogen mixture pipeline network, The experimental deflagration quenching behavior of porous materials on hydrogen mixed methane in barrier tubes was studied, the influence of the hydrogen mixing ratio on the quenching results of porous materials and the transient change of overpressure was discussed, the critical quenching hydrogen mixing ratio of porous materials was explored. Results show that the hydrogen mixing ratio has a significant effect on the quenching results of porous materials. According to the different quenching results of porous materials under different hydrogen mixing ratios, the successful quenching zone (φ<19%) and the quenching failure zone (φ ≥ 19%) can be divided. It can be determined that the critical quenching hydrogen mixing ratio is φ = 19%. The critical quenching speed is 33.0 m/s. When the porous material is coupled with hydrogen mixing, the pressure curve appears as a “multi-peak” phenomenon, and the maximum pressure peak is generated by the “multi-peak” game. If the hydrogen mixing ratio is greater than the critical quenching hydrogen mixing ratio, it may bring about the uncertainty of the maximum pressure peak and increase the unpredictability of the explosion hazard to the gas pipeline network. Therefore, reasonable hydrogen mixing is conducive to improving the safety of methane/hydrogen mixture pipeline network transportation. The research results could provide an important reference for the engineering application of methane/hydrogen mixture flame arrester design and the selection of safe hydrogen concentration.