The effect of the way of setting boundary conditions on the results of modeling a flow at the flameholder outlet

The influence of different algorithms of generating inlet turbulent fluctuations on the results of calculating the flow parameters downstream the flameholder is discussed in the paper. Large eddy simulation is used on a turbulence model with a subgrid Smagorinsky-Lilli model. Propane-air mixture with a temperature of 300 K in a square-section channel is investigated. A bluff body with a base of an equilateral triangle with the side length equal to 25 mm is placed inside the channel. The mass-averaged inlet velocity is 10 m/s. Several ways of setting inlet boundary conditions are considered. Two cases without turbulence at the inlet (uniform velocity distribution across the inlet section and pipe velocity profile) and two cases with artificially modeled turbulence (vortex method and spectral turbulence synthesizer) are analyzed. The values of flow intensity upstream the stabilizer, the distribution of flow velocity and kinetic energy in longitudinal and cross sections downstream the stabilizer have been obtained. The graphs of the velocity fluctuation power density spectrum are also presented.