Modelling large-scale vented gas explosions in a twin-compartment enclosure

•Eighty-five gas explosion experiments were conducted in a two-chamber enclosure.•A selection of experiments was simulated using the CFD tool FLACS.•Flame propagation and pressure build-up in the two rooms were studied.•Higher failure pressure of vent panels and inserting door may increase severity.

Natural gas and LPG are common fuels that have been used relatively safely in the home for many decades. However, when there is a release of gas within a dwelling, or gas from a leaking external pipeline migrates into a building, an explosion may occur. Most of the experimental research into vented gas explosions has been conducted in single enclosure, cuboid or spherical geometries which are not representative of accidental explosions in dwellings or process industries. This paper discusses the findings of a comprehensive large-scale experimental programme undertaken by British Gas Research and Development and also compares FLACS CFD (Computational Fluid Dynamics) simulations against a number of these experiments. The results suggest that the software is useful in gaining a greater understanding of the dynamics of explosion development in dwellings. The paper highlights areas of good performance of the software as well as areas of shortcomings where further understanding and modelling effort is needed.