Studying of gas deflagration is important for a safety purpose in gas industry. A modelling
approach based on large eddy simulation (LES) technique for modelling turbulent flow
combined with the species mass fraction equations for modelling combustion is used.
Different flame acceleration mechanisms, hydrodynamic & thermo-diffusive instabilities,
turbulence, and their interaction in addition to flame quenching model are used to model
chemical reaction rate. An algebraic model for flame-generated turbulence is
incorporated. The model is tested against large scale open atmosphere hydrogen-air experiment. The
flame propagation radius and the overpressures are qualitatively compared well with
experiment and the state-of-the-art simulations.