Abstract
The ability of chevrons at the top edge of a backward-facing step to reduce downstream surface pressure fluctuations is investigated numerically. Three different chevron configurations are compared against a baseline case without chevrons. Low frequency reduction in the surface pressure fluctuations is observed for two of the configurations. The chevrons do not appear to have a significant effect on the flow as the mean reattachment length for all configurations is nearly constant and there is only a small increase in streamwise turbulence for one configuration with the other configurations unchanged.
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Acknowledgments
Joachim Hodara at Georgia Institute of Technology is gratefully acknowledged for sharing his implementation of the Lund inlet BC. This work was supported by the Swedish Governmental Agency for Innovation Systems (VINNOVA) and SAAB AB under the National Aviation Research Programme (NFFP5). The simulations were performed on resources provided by the Swedish National Infrastructure for Computing (SNIC) at Lunarc and HPC2N.
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Nilsson, J., Szász, RZ., Austrell, PE., Gutmark, E.J. (2016). Passive Load Control in Backward-Facing Step Flow by Using Chevrons. In: Segalini, A. (eds) Proceedings of the 5th International Conference on Jets, Wakes and Separated Flows (ICJWSF2015). Springer Proceedings in Physics, vol 185. Springer, Cham. https://doi.org/10.1007/978-3-319-30602-5_28
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DOI: https://doi.org/10.1007/978-3-319-30602-5_28
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