Evaluation of blast wave from hydrogen pipeline burst by a coupled fluid-structure-rupture approach.

Coupled fluid-structure-rupture model was developed to evaluate the blast field from X65 hydrogen pipeline burst. Johnson-Cook material model was implemented considering the high strain rates of material at crack tips. Internal hydrogen decompression, outer blast wave generation and propagation, and dynamic rupture of pipeline were simulated simultaneously and validated with experiments. Results demonstrated that the crack primarily ran axially at an average speed of about 120 m/s, while the maximum speed was about 200 m/s. Due to the dynamic growth of rupture opening, the outer blast wave experienced a process of first form and then strengthened by subsequent compression waves. This makes the maximum peak overpressure along the jetting direction appears at a certain standoff distance above rupture. The blast overpressures along the jetting direction were compared and discussed with those from traditional CFD method, TNT equivalence method and Baker-Tang blast curves. It was found the effective volume to calculate the burst energy needs to be further studied. Also, new blast curves were required for quick and rational estimation of blast overpressure from hydrogen pipeline burst. • Coupled fluid-structure-rupture method offers improvements of hazards assessments. • Flow behavior and dynamic rupture of pipeline were well coupled together. • Maximum peak overpressure appears at a certain standoff distance above rupture. • New blast curves are needed to estimate blast overpressure along jetting direction. [ABSTRACT FROM AUTHOR]