Bifurcation Tracking for High Reynolds Number Flow Around an Airfoil

Abstract

High Reynolds number flows are typical for many applications including those found in aerospace. In these conditions non-linearities arise which can, under certain conditions, result in instabilities of the flow. The accurate prediction of these instabilities is vital to enhance understanding and aid in the design process. The stability boundary can be traced by following the path of a bifurcation as two parameters are varied using a direct bifurcation tracking method. Historically, these methods have been applied to small-scale systems and only more recently have been used for large systems as found in Computational Fluid Dynamics. However, these have all been concerned with flows that are inviscid. We show how direct bifurcation tracking methods are can be applied efficiently to high Reynolds number flows around an airfoil. This has been demonstrated through the presentation of a number of test cases using both flow and geometrical parameters.

An Investigation of the Bifurcation Behavior of an F-18 Aircraft Model

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Numerical continuation in nonlinear experiments using local Gaussian process regression

“…Bifurcations, and hence stability changes, in those behaviours can then be detected along the solution path and in turn tracked by adding suitable constraint condition(s) and free parameter(s). The principles of numerical continuation are extremely general such that the method has been applied to a wide range of problems across engineering and the applied sciences as, for instance, in bio-chemistry [3], physics [4], mechanics [5] and fluid dynamics [6].…”