Modification of the $k-\omega_0$ model for roughness

Paul Durbin; Zifei Yin

doi:10.2514/1.j066816

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arXiv · 2603.22737

Modification of the $k-\omega_0$ model for roughness

Paul Durbin·Zifei Yin

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Abstract

Surface roughness plays a substantial role in many flows for which Reynolds averaged prediction is needed. The transformation used in the k-omega0 model is extended to rough surfaces by adding an effective origin. The log-layer offset is computed as a function of this effective origin, thereby creating a correspondence between effective origin and equivalent sandgrain roughness. A formula is derived for the virtual origin of the fully rough log law. It is shown how the present model is consistent with the fully rough limit.

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Paul Durbin, Zifei Yin. 2026-03-24. Modification of the $k-\omega_0$ model for roughness. https://doi.org/10.2514/1.j066816

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