Investigation of the Influence of the Inlet Geometry on the Flow in a Swirl Burner
A series of Large Eddy Simulations (LES) of non-reacting flow in a swirl burner has been performed. The configuration consists of two unconfined co-annular jets at a Reynolds number of 81500. The flow is characterized by a Swirl number of 0.93. Two cases are studied differing with respect to the axial location of the inner pilot jet. It was observed in a companion experiment (Bender and Büchner, 2005)  that when the inner jet is retracted the flow oscillations are considerably amplified. The present simulations allow to understand this phenomenon: the recirculation zone and the jet interact in such a way that large scale coherent structures are generated. The resulting spectra correspond well to the experimental data.
KeywordsReynolds Number Heat Release Large Eddy Simulation Navier Stoke Equation Coherent Structure
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