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arXiv · 2607.22171

Integral relations for the skin-friction coefficients and other quantities of annular flows

Pierre Ricco
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Abstract

Integral identities relating the skin-friction coefficients and the Reynolds shear stresses in annular cylindrical flows are derived. In the pressure-driven case, an identity for the radial location of the maximum streamwise velocity is obtained and, in the cylinder-driven case, an identity for the bulk velocity is found. The formulas are used to analyse existing numerical and experimental data and simplify to classical channel-flow and pipe-flow identities in the limiting cases of vanishingly small and infinitely large radius ratios.

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Pierre Ricco. 2026-07-24. Integral relations for the skin-friction coefficients and other quantities of annular flows. https://arxiv.org/abs/2607.22171

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