Exploration of Factors and Mechanisms Affecting Hydrogen Explosion in Confined Spaces

To examine hydrogen explosion characteristics and propagation in confined spaces, providing a theoretical basis for prevention and mitigation, experiments were conducted in a 20‐L spherical vessel at various hydrogen concentrations. Computational fluid dynamics simulations analyzed explosions under different initial conditions (concentration, ignition source temperature, initial temperature, and initial pressure). Results show that higher hydrogen concentration reduces the induction period, increasing pressure rise rate and peak values of pressure and temperature. Greater ignition source temperature and pressure also boost the pressure rise rate, slightly raise peak pressure, and increase maximum temperature. Elevated initial temperatures speed up the pressure rise but decrease peak pressure. Qualitative and quantitative analyses of explosion parameters like explosion impulse, explosive energy, and detonation index were performed to explain hydrogen explosion mechanisms.