Numerical modelling of hydrogen leakages in confined spaces for domestic applications

• Published in: International journal of hydrogen energy 2024-02, Vol.56, p.797-806
• Main Authors: Thawani, B., Hazael, R., Critchley, R.
• Format: Article
• Language: English
• Subjects: Energy; Gas leak; Hydrogen; Modelling and simulation; Security
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2023.12.279

The UK government tentatively plans to use hydrogen for domestic applications by 2035. While the use of hydrogen aims to reduce the dependence on hydrocarbons, certain factors need consideration. Since hydrogen is much lighter, and more reactive than methane, it is crucial to understand the change in risk for accident scenarios involving hydrogen in a domestic setting. Numerical modelling was used to simulate the leakage of hydrogen and methane in small, enclosed spaces such as kitchen cupboards. The k- ε turbulence model was used along with the species transport model to simulate the leakage of gas for different inlet locations and leak diameters (1.8 mm–7.2 mm). From the modelling study, it was observed that hydrogen and methane both tend to stratify from top of the control volume to the bottom. The key finding was that, under adverse conditions (leak from a 7.2 mm diameter hole) and due to greater volumetric flow, hydrogen tends to reach equilibrium concentration 45s faster than methane for a total leak duration of 600s. Additionally, it was noted that cases with leak inlet locations near corners had 28% lower hydrogen concentrations, and 25% lower methane concentrations as compared to leak inlet locations near the centre of the cupboard. •Hydrogen has the potential to be used as fuel for domestic applications.•Hydrogen and Methane leakages were visualised using k-ε model and species transport model.•Hydrogen leak from a 7.2 mm hole reached maximum concentration 45–300s faster than a 2.5 mm hole.•Hydrogen concentration in the idealised cupboard reached up to 25% in air compared to methane concentration in air (10%).