The large eddy simulation (LES) is applied to an unconfined swirling flow of an air surrounding a bluff-body having a central jet of air, and the complicated flowfield that involves the recirculation and vortex breakdown is investigated. The Smagorinsky model is used as the sub-grid scale model. The results of the present numerical simulation are compared with the experimental data of the mean and stochastic root mean square (RMS) variations of two velocity components. Although the inflow conditions are specified in a simple manner, the obtained numerical results are in reasonable agreement with the expiriments, except for a part of RMS variation values near downstream of the bluff body. The present numerical calculations can successfully reproduce the characteristics of the flow, i.e., an upstream recirculation zone established just downstream of the burner plane. Additionally, the flowfield is much different by the swirl number and axial velocity of the primary swirling air. Especially the additional recirculation zone is established at the more downstream location in the lower swril number and higher axial velocity of the primary swirling air.
|ジャーナル||Nihon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B|
|出版ステータス||出版済み - 1月 2006|
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