Abstract
This paper reports a large eddy simulation (LES) of the precession-like oscillation produced by partially confining a triangular-jet flow with a short cylindrical chamber. The present LES, which has been verified by previous experimental data, shows that there is a strong inward swirl around the jet near the inlet end of the chamber. At the center of the swirl, there is a cluster of three sink foci, where each focus is aligned midway between the corners of the triangular inlet orifice. In the time-averaged flow field, the vortices rising from the foci are helically twisted about the core of the jet. As the flow passes through the chamber, the foci merge to form a closed-loop “bifurcation line” which separates the inward swirl and the core flow. The core of the emerging jet is visible as a source node at the approximate centerline of the chamber. If the chamber is removed, a cluster of six counter-rotating foci is produced in the “free” jet. When this happens, the net swirl circulation is zero and there is no jet oscillation.
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References
England G, Kalt P, Nathan G, Kelso R (2010) The effect of density ratio on the near field of a naturally occurring oscillating jet. Exp Fluids 48:69–80
Lee SK (2009) Study of a naturally oscillating triangular-jet flow. The University of Adelaide, South Australia. http://hdl.handle.net/2440/58581
Mi J, Nathan GJ, Luxton RE (2004) Family of oscillating jets. Pat App No. PCT/AU98/00959. The US Patent No. 6685102 (2004.2), European Pat. No. 1032789 (2004.9), Australian Pat. No. 746248 (2004.2), New Zealand Pat. No. 504470 (2003.7)
Nathan GJ, Mi J, Alwahabi ZT, Newbold GJR, Nobes DS (2006) Impacts of a jet’s exit flow pattern on mixing and combustion performance. Prog Energy Combust Sci 32:496–538
Xu M, Mi J, Li P (2012) Large Eddy simulation of an initially-confined triangular oscillating jet. Flow, Turbulence Combus 88:1–20
Xu M, Zhang J, Mi J, Nathan GJ, Kalt PAM (2013) PIV measurements of turbulent jets issuing from triangular and circular orifice plates. Sci China, Ser G 56:1176–1186
Acknowledgments
This project is financially supported by the Fundamental Research Funds for the Central Universities (Grant No. 3132013029) and the Nature Science Foundation of China (Grant Nos. 11072005 and 10921202).
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Xu, M., Lee, S.K., Mi, J., Li, P., Zhang, J. (2014). Comparison of the Near-Field Flow Structures of a Triangular Jet with and without the Initial Confinement of a Chamber. In: Zhou, Y., Liu, Y., Huang, L., Hodges, D. (eds) Fluid-Structure-Sound Interactions and Control. Lecture Notes in Mechanical Engineering. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-40371-2_21
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DOI: https://doi.org/10.1007/978-3-642-40371-2_21
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