Research on the flow characteristics and self-ignition mechanism of high-pressure hydrogen jets in bifurcated tubes

Abstract

This manuscript provides insights into the characteristics of shock wave propagation and flame development mechanisms in bifurcated tubes due to accidental leakage from a high-pressure hydrogen storage unit in the energy and chemical industries. Incorporating the non-stop working process of tube plugging in gas transportation in industrial production, two types of bifurcated tubes with axial and normal blocking are designed. The experimental results indicate that, compared to straight tube, both types of blocking tube structures can effectively reduce shock wave pressure intensity at the nozzle. Under the initial burst pressure of 8 MPa, the lowest shock wave pressure at the nozzle of the axially blocking tube is just 0.47 MPa. However, the peak shock wave pressure inside the blocking tubes is higher, and the ignition critical pressure is lower. Within the axially sealed blocking tube, flame quenching is observed, offering experimental support for mitigating the development of continuous jet fires outside of high-pressure hydrogen tubes.