Tracking the explosion characteristics of the hydrogen-air mixture near a concrete barrier wall using CESE IBM FSI solver in LS-DYNA incorporating the reduced chemical kinetic model

• The explosion characteristics of the hydrogen-air mixture near a concrete barrier wall were captured. • The CESE solver based on the immersed boundary method was utilized and coupled with the LS-DYNA® structural FEM solver. • The reduced chemical kinetic model was used to describe the hydrogen-air explosion. • The numerical model was verified with existing experimental data and compared with the conventional TNT equivalent method. • TNT equivalent method is just reliable to capture the 1st peak overpressure in front of the barrier wall. • CESE approach with the reduced chemical kinetic model accurately predicts all the explosion characteristics in front of and behind the barrier wall. Barriers are introduced as an efficient method for the protection of infrastructures and people from overpressure effects owing to accidental gaseous explosions. Therefore, capturing the pressure wave propagation in front of and behind the barrier plays an important role in designing a protective wall and hazard analysis of pipeline explosion accidents. To this end and to track the explosion characteristics of the hydrogen-air mixture near a concrete barrier wall, a new numerical approach in the compressible CESE solver based on the immersed boundary method (IBM) was utilized and coupled with the LS-DYNA® structural FEM solver in which the finite-rate chemistry model was in touch with the fluid-structure interaction (FSI). For the wall, the Concrete Damage Model (MAT_72R3) was employed as the constitutive material model. Existing experimental results were utilized to verify the 3D numerical model. Furthermore, the obtained numerical simulation results were compared with the conventional numerical approach called the TNT equivalent method using the MMALE algorithm in the open literature to show its drawbacks in predicting the pressure wave propagation in front of and particularly behind the wall surface. The results showed that by incorporating the finite-rate chemistry model in the CESE IBM FSI solver, all the explosion characteristics related to the hydrogen-air mixture detonation in front of and behind the wall surface can be accurately predicted since it involves detonation wave/structure interaction, chemical reaction, fluid motion, and structural deformation. Therefore, it is strongly recommended to use the CESE IBM FSI solver in conjunction with appropriate chemical kinetics as an alternative method instead of the conventional method to accurately model the gaseous mixture explosion process in a relatively complex environment and solve more practical applications in explosion and safety industries.