Numerical simulation of the effect of multiple obstacles inside the tube on the spontaneous ignition of high-pressure hydrogen release

• Published in: International journal of hydrogen energy 2022-09, Vol.47 (77), p.33135-33152
• Main Authors: Li, Xigui, Teng, Lin, Li, Weidong, Huang, Xin, Li, Jiaqing, Luo, Yu, Jiang, Lilong
• Format: Article
• Language: English
• Subjects: Computational fluid dynamics; High-pressure hydrogen release; Obstacle; Shock wave; Spontaneous ignition
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2022.07.202

Self-ignition may occur during hydrogen storage and transportation if high-pressure hydrogen is suddenly released into the downstream pipelines, and the presence of obstacles inside the pipeline may affect the ignition mechanism of high-pressure hydrogen. In this work, the effects of multiple obstacles inside the tube on the shock wave propagation and self-ignition during high-pressure hydrogen release are investigated by numerical simulation. The RNG k-ε turbulence model, EDC combustion model, and 19-step detailed hydrogen combustion mechanism are employed. After verifying the reliability of the model with experimental data, the self-ignition process of high-pressure hydrogen release into tubes with obstacles with different locations, spacings, shapes, and blockage ratios is numerically investigated. The results show that obstacles with different locations, spacings, shapes and blockage ratios will generate reflected shock waves with different sizes and propagation trends. The closer the location of obstacles to the burst disk, the smaller the spacing, and the larger the blockage ratio will cause the greater the pressure of the reflected shock wave it produces. Compared with the tubes with rectangular-shaped, semi-circular-shaped and triangular-shaped obstacles, self-ignition is preferred to occur in tube with triangular-shaped obstacles. [Display omitted] •Effects of multiple obstacles on hydrogen self-ignition is numerically studied.•The simulation results are compared and verified with the experimental data.•The effects of obstacle location, spacing, shape, and blockage ratio on the shock wave propagation are analyzed.•Reflected shock wave generated by obstacle will spread both upstream and downstream.