Numerical Study of Propane and Hydrogen Turbulent Premixed Flames in a Small Scale Obstructed Chamber.

This paper presents numerical study of turbulent premixed flames characteristics of two different fuel/air mixtures, namely propane and hydrogen. The flames under study are propagating past solid baffle plate(s) in a small-scale combustion chamber. The chamber design allows for up to three baffle plates to be inserted followed by a square obstacle to promote the generation of turbulence. The test cases considered in this paper examine various configurations of the baffles and one central obstacle at a fixed equivalence ratio of 0.8. An in-house computational fluid dynamics (CFD) model is used to numerically evaluate the characteristics of the flame propagation. The large eddy simulation (LES) technique is used for turbulence flow modelling. Three different flow configurations with various obstacles positioning are used to highlight the generated overpressure and flame speed. The numerical results are then validated against published experimental data to confirm the capability of computational models in capturing the features of hydrogen and propane flames. A conclusion is drawn that different configurations affect the generated peak overpressure as well as the flame structure. It was also concluded that hydrogen flames generated a significantly greater peak overpressure inside the combustion chamber when compared to propane.