An adaptive selective frequency damping method

Bastien E. Jordi; Colin J. Cotter; Spencer J. Sherwin

doi:10.1063/1.4932107

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arXiv · 1412.4372

An adaptive selective frequency damping method

Bastien E. Jordi·Colin J. Cotter·Spencer J. Sherwin

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Abstract

The selective frequency damping (SFD) method is an alternative to classical Newton's method to obtain unstable steady-state solutions of dynamical systems. However this method has two main limitations: it does not converge for arbitrary control parameters; and when it does converge, the time necessary to reach the steady-state solution may be very long. In this paper we present an adaptive algorithm to address these two issues. We show that by evaluating the dominant eigenvalue of a "partially converged" steady flow, we can select a control coefficient and a filter width that ensure an optimum convergence of the SFD method. We apply this adaptive method to several classical test cases of computational fluid dynamics and we show that a steady-state solution can be obtained without any a priori knowledge of the flow stability properties.

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Bastien E. Jordi, Colin J. Cotter, Spencer J. Sherwin. 2014-12-14. An adaptive selective frequency damping method. https://doi.org/10.1063/1.4932107

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