Structured input-output analysis of oblique turbulent bands in Waleffe flow

Jino George; Chang Liu

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arXiv · 2605.12166

Structured input-output analysis of oblique turbulent bands in Waleffe flow

Jino George·Chang Liu

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Abstract

This work employs structured input-output analysis (SIOA) to study Waleffe flow. The SIOA framework employs structured uncertainty to include the componentwise structure of nonlinearity in Navier-Stokes equations, and SIOA quantifies the flow response using structured singular values. The structured input-output analysis identifies the wavelength and inclination angle of oblique turbulent bands observed in large-domain direct numerical simulations. The structured input-output response scales over Reynolds number as $\sim Re^{1.7}$.

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Jino George, Chang Liu. 2026-05-12. Structured input-output analysis of oblique turbulent bands in Waleffe flow. https://arxiv.org/abs/2605.12166

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