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arXiv · 2104.08652

Significance of the strain-dominated region around a vortex on induced aerodynamic loads

Karthik Menon·Rajat Mittal
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Abstract

The ability of vortices to induce aerodynamic loads on proximal surfaces plays a significant role in a wide variety of flows. However, most studies of vortex-induced effects primarily focus on analyzing the influence of the rotation-dominated cores of vortices. In this work, we show that not only are vortices in viscous flows surrounded by strain-dominated regions, but that these regions are dynamically important and can sometimes even dictate the induced aerodynamic loads. We demonstrate this for a pitching airfoil, which exhibits dynamic stall and generates several force-inducing vortices. Using a data-driven force partitioning method, we quantify the influence of vortices as well as vortex-associated strain to show that our current understanding of vortex-dominated phenomena, such as dynamic stall, is incomplete without considering the substantial effect of strain-dominated regions that are associated with vortices.

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Karthik Menon, Rajat Mittal. 2021-04-17. Significance of the strain-dominated region around a vortex on induced aerodynamic loads. https://doi.org/10.1017/jfm.2021.359

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